Sunglasses can block unpleasant glare and protect your eyes from the eye
Sunglasses (2 photos)Damaged by ultraviolet rays. All of this is due to the metal powder filter, which “selects” the light as it enters. Colored glasses selectively absorb some of the wavelength bands that make up the sun’s rays because they rely on very fine metal powders (iron, copper, nickel, etc.). In fact, when the light hits the lens, the light is diminished based on the so-called “destructive interference” process. That is to say, when the light of certain wavelengths (herein referred to as ultraviolet light a, ultraviolet light b, and sometimes infrared light) passes through the lens, they cancel each other in the direction of the inner side of the lens, that is, toward the eye. The mutual overlap of the formation of light waves is not an accidental phenomenon: the peaks of one wave are combined with the waves of the waves that are close to them, resulting in mutual cancellation. The destructive interference phenomenon depends on the refractive index of the lens (ie, the extent to which light deviates from the air through different materials) and also depends on the thickness of the lens. In general, the thickness of the lens does not change much, and the refractive index of the lens varies depending on the chemical composition. Polarized glasses provide another mechanism to protect the eye. The reflected light of the asphalt road is a special polarized light. The difference between this reflected light and the light directly from the sun or any artificial light source lies in the order problem. Polarized light is formed by waves that are all vibrating in one direction, while ordinary light is formed by waves that are not directional vibrations. It is like a group of people who walk around in disorder and walk with a group of soldiers marching neatly. Formed a distinct confrontation. In general, the reflected light is an orderly light. Polarized lenses are particularly effective at blocking such light because its filterability is working. This type of lens only allows polarized waves that vibrate in a certain direction to pass, just like “lighting up” the light. For road reflection problems, the use of polarized glasses can reduce the transmission of light because it does not allow light waves that vibrate in parallel with the road to pass. In fact, the long molecules of the filter layer are directed horizontally and absorb horizontally polarized light. In this way, most of the reflected light is eliminated, and the overall illumination of the surrounding environment is not reduced.
The lenses of the color-changing glasses can be darkened after the sun’s rays are emitted. When the lighting fades, it becomes bright again. This is because the crystal of silver halide is working. Under normal conditions, it keeps the lens perfectly transparent. Under the illumination of sunlight, the silver in the crystal separates, and the free silver forms a small aggregate inside the lens. These small silver aggregates are irregular blocks that are interlaced by dogs. They are unable to transmit light, but only absorb light, which results in darkening of the lens. In the case of light darkness, the crystals are re-formed and the lens returns to a bright state.basic skillset ForewordA pair of sunglasses looks very simple, that is, there are two colored pieces of glass or plastic in a plastic or metal frame. Is it even simpler than this? In fact, two glass lenses can make a lot of difference, and when you use sunglasses, these differences will have a great impact on you.effectUltraviolet rays can damage the cornea and retina, and high-quality sunglasses completely eliminate ultraviolet light.When the eye receives too much light, it naturally shrinks the iris. Once the iris has contracted to its limit, then people need to blink. If the light is still too much, such as the sunlight reflected from the snow, it will damage the retina. High-quality sunglasses filter up to 97% of the incoming light to avoid injury.
Some surfaces, such as the water surface, can reflect a lot of light, and the resulting bright spots can disturb the line of sight or hide objects. High-quality sunglasses can completely eliminate such glare using polarizing technology, and we will introduce polarizing technology later. Light at certain frequencies blurs the line of sight, while light at other frequencies enhances contrast. Choose the right color for your sunglasses to get the best results in your particular environment. If the sunglasses don’t provide UV protection, it will expose you to more UV light. Cheap sunglasses filter out some of the light, causing your iris to open to receive more light. This will also allow more UV rays to enter, increasing the damage that the UV rays cause to the retina. Therefore, there is indeed a difference between the various sunglasses. Choosing the right, quality sunglasses will give you maximum protection for your specific environment.
According to international standards, sunglasses are listed as a category of personal eye protection products. The main function of sunglasses is to block the glare of the sun. However, international standards have subdivided sunglasses into “fashion mirrors” and “general purpose mirrors.” The quality requirements for “fashion mirrors” are relatively low in the standard. Because the “fashion mirror” mainly highlights the style, the wearer pays attention to the decoration, not the protection function. In the standard, the quality requirements for general purpose mirrors are strict, including the requirements for UV protection, as well as diopter and prismatic. Sunglasses can be divided into sunshade mirrors, light-colored sunglasses, and special-purpose sunglasses.SunglassesThe so-called sun visor, as the name suggests is used for sunshade, people in the sun usually rely on adjusting the size of the pupil to adjust the luminous flux, when the light intensity exceeds the ability of the human eye to adjust, it will cause damage to the human eye. Therefore, in outdoor activities, especially in the summer, many people use sunshades to block the sun to reduce the fatigue caused by eye adjustment or the damage caused by strong light stimulation.Light-colored sunglasses are not as good as sunshade mirrors, but they are rich in color and are suitable for use with all kinds of clothing. They have a strong decorative effect. Light-colored sunglasses are favored by young people because of their rich colors and diverse styles. Fashion women are more fond of them. Special-purpose sunglasses have a strong function of blocking sunlight. They are commonly used in beaches, skiing, mountain climbing, golf and other fields with strong sunlight. Their UV resistance and other indicators have higher requirements.Different people choose sunglasses according to different preferences and different uses, but the most fundamental thing is to start from the basic principle of ensuring the wearer’s safety and vision without damage. Reducing glare stimulation, clear and non-deformation of vision, anti-UV, no distortion of color recognition, and accurate identification of traffic signals should be the basic functions of sunglasses. If the above functions are defective, the effect of sunglasses will be lost, and the symptoms will be dizzy, sore eyes and other symptoms that are not suitable for the symptoms. Sometimes, there will be unresponsiveness, the illusion of color and unequal symptoms of walking and traffic accidents. So choosing sunglasses can’t just focus on the style and ignore their inner quality.
Sunglasses are broadly classified into five types: anti-reflective protective lenses, colored lenses, painted lenses, polarized lenses, and color-changing lenses.1. Anti-reflective protective lens: This kind of lens is coated with a thin layer of magnesium fluoride to prevent strong light reflection so that you can see things more clearly and not interfere with strong light. To check if your sunglasses are really anti-reflective lenses, align the glasses with the light source. If you see a purple or green reflection, it means that there is indeed an anti-reflective protective film on the lens.2. Colored lenses: Also known as “stained lenses”, in the process of making lenses, adding some chemicals to make the lenses appear color to absorb light of a specific wavelength. This is the type of lens most commonly used in sunglasses.3. Coloring lens: This lens presents the same effect as a colored lens. It is only made in a different way. It is applied to the surface of the lens. The most well-known is the “gradual color coating lens”. The color is The deepest above, then fade down. Generally, sunglasses with degrees are mostly processed by coloring.4. Polarized lenses: In order to filter the glare of the sun in the equal direction on the surface of the water, land or snow, a vertical special coating is added to the lens, which is called a polarized lens. Ideal for outdoor sports such as sea activities, skiing or fishing.5. Color-changing lenses: Some people also call them “photosensitive lenses.” Because the silver halide chemical is added to the lens, the original transparent and colorless lens will become a colored lens when it is exposed to strong light, so it is suitable for indoor and outdoor use.6. Sunglasses clips: Sunglasses clips are polarized sunglasses designed for myopic people, effectively preventing glare and UV rays . Especially suitable for outdoor sports such as driving, outdoor, fishing. With polarized lens technology, the resolution of the video is greatly improved. Eliminate 99% of reflected and scattered light to make your field of vision clearer and more compliant. The lens is specially reinforced with a film to effectively resist abrasion, scratch, and impact.7. Driving the lens at night: driving the lens at night should block more than 80% of the glare of the other car, and the transmittance of the main lens must be >75%. Observing the road is not affected, wearing a good driving night vision goggle at night, driving the family Not only can you see the road surface, but also can effectively reduce the glare and other harmful light from the headlights of the other car, and can clearly see the road while blocking the strong light, thus ensuring your driving safety.
(1) Gray film: The gray lens can absorb evenly in any chromatogram, so the viewing scene will only darken, but there will be no obvious color difference, showing a truly natural feeling. It belongs to the neutral color system.
(2) Brown lens: It can improve the visual contrast and sharpness by filtering out a large amount of blue light, and it is better to wear in the case of serious air pollution or fog. Generally, it can block the reflected light from the smooth and bright surface, and the wearer can still see the fine arts, which is the ideal choice for the driver.
(3) Green lens: While absorbing light, it maximizes the green light reaching the eyes, so it has a cool and comfortable feeling and is suitable for people who are prone to fatigue.(4) Blue-gray lens: similar to the gray lens, it belongs to the neutral lens, but the color is deeper and the visible light absorption rate is higher.(5) Mercury lens: The surface of the lens is coated with a high-density mirror. Such lenses are more absorbed into the visible light and are suitable for outdoor sports.(6) Yellow lenses: Strictly speaking, such lenses are not sunglass lenses because they hardly reduce visible light, but in foggy and dusk moments, yellow lenses can improve contrast and provide more accurate video, so it is also called night vision. mirror. Some young people wear yellow lenses “sunglasses” as a decoration.(7) Light blue, light pink and other lenses: the same is more decorative than practical lenses.(8) Dark green lens: absorbs hot air and brings a cool feeling, but the light transmittance and clarity are low. It is suitable for wearing in the sun and not suitable for driving.(9) Blue lens: The beach at the seaside can be worn with sun blue lenses, and the blue color can effectively filter out the light blue reflected by sea water and sky. Blue lenses should be avoided when driving, as it will make us unable to distinguish the color of traffic signals.
1. The human body has an instinctive reaction to self-protection. When the eye encounters strong light, the pupil will naturally become smaller, so that the ultraviolet energy entering the eye is reduced. Once the glasses without anti-UV function are worn, the pupil will be enlarged, plus this. The glasses do not have the effect of isolating ultraviolet rays. At this time, the eyes are wide open to the portal, and the ultraviolet rays can be entered. The damage to the eyes can be imagined.2. Sunglasses can block ultraviolet rays because a special coating film is added to the lens, and the inferior sunglasses can not only block the ultraviolet rays, but also cause the lens transmittance to be seriously reduced, so that the pupils become larger, and the ultraviolet rays will be injected in a large amount. Eye damage. In addition, inferior lenses also cause nausea, forgetfulness, insomnia and other visual fatigue symptoms.
3, the color of the sunglasses is light gray, brown or light smoke, followed by green, amber, blue, etc. Red is only used as a sunbathing or snow.4, it is best to use polarized sunglasses when riding a car because they can reduce the glare of glare.5. If you can see your eyes very clearly after wearing sunglasses, your lens is too light.
6. When the sun goes down, it is best to remove the sunglasses. Otherwise, our vision will be affected in places with weak light.7, should go to the regular optical shop to choose the regular manufacturers to produce sunglasses with anti-UV function.8. Pay attention to the surface condition of the lens when selecting.9, when buying sunglasses, you can judge according to whether the object is clear. To buy quality sunglasses, the only thing you can do is to buy sunglasses at optical specialty stores and regular optical shops.10, face modification:
1 Round face: You need a straight or angular frame to weaken your contours. Use a deep, subtle color lens to reduce obesity and make your face look more exquisite.2 square face: Contrary to the round face, you need some rounded, streamlined frame to set off your extraordinary temperament.3 triangle face type: Please try to avoid using the large frame, square frame, because it will appear wider and narrower on the face, using a thin frame, a round frame, the color is brightest.4 oval face: You are born to be very suitable for Taiwan sunglasses. No matter what style is right for you, pay attention to the size ratio.5 rectangular face: You are most suitable for large frame sunglasses, which can make up for the shortcomings of the face length, make the face look more delicate, and the color is mainly dark.
marketedMany famous brands use sunglasses as part of their product line. Many sunglasses manufacturers will also advertise the features and special qualities of their products. Depending on the characteristics and brand, the price of sunglasses will fluctuate between less than $20 and a few hundred dollars.In addition, there will be counterfeit goods on the market. When you go to discount stores and flea markets, you will find that vendors sell counterfeit goods that mimic high-priced branded sunglasses. They look exactly the same, but the price is much lower than the real one. When you buy genuinely branded sunglasses instead of counterfeit goods, do you spend a lot of money buying a brand, or is it really a fundamental difference?The biggest problem with cheap sunglasses is the way the lenses are made. They simply plate a layer of colored film on plain plastic. Even though the colors and frames of these counterfeit goods are similar to some famous brands, the actual lenses are quite different.
High-quality sunglasses are very effective “light regulators”. Sunglasses can adjust the external light to make it suitable for the human eye. In the next section, sunglasses SunglassesVarious techniques for adjusting light used by sunglasses manufacturers will be introduced. In order to better understand these technologies, you must first understand some knowledge about light.A beam of light has a certain amount of electromagnetic energy. The size of the wave is measured in terms of wavelength. The wavelength of visible light ranges from 400 to 700 nanometers. The energy of a light wave is inversely proportional to the wavelength. The shorter the wavelength, the higher the energy. Invisible light, the violet light energy is the largest, the red light energy is the smallest, and the ultraviolet light is above the visible light spectrum. In fact, natural light contains a lot of ultraviolet light. Due to the high energy of ultraviolet light, ultraviolet light can damage your cornea and retina. What is glare? The measure of the brightness or intensity of light is lumens. For example, indoors, most artificial light has an intensity of 400 to 600 lumens. If it is sunny outdoors, the brightness will fluctuate within a wide range. The brightness in the shade is 1000 lumens, and in places with large cement floors such as highways, the brightness is 6000 lumens. Below 3,500 lumens, our eyes feel comfortable. When the brightness of direct or reflected light reaches 4000 lumens, the human eye receives light and becomes strenuous. When we try to look at these very bright areas, we only see the white flash, which is glare. In order to reduce the discomfort caused by a large amount of light entering the eyes, we began to blink. Once the light reaches 10,000 lumens, your eyes begin to completely filter out the light because the received light is too strong. Excessive exposure to such strong light can cause damage, resulting in temporary or even permanent blindness. On a clear day, a large piece of snow reflects a brightness of up to 12,000 lumens, and if we look at the light without any protective measures, it will cause “snow blindness.”Visible light is light that the human eye can perceive. The visible light we see from the sun looks colorless, which is what we often call white light. In fact, it is a mixture of colored light of multiple frequencies. Light from a mixture of all colored light in the spectral range of visible light is colorless, ie white. (For details, see Principles of Light).We have two basic ways to see colors. One way is that an object itself can emit light of a certain frequency. For example, a neon light displays the color. Another way is that the object absorbs light of all other frequencies, but only reflects light of a certain frequency, or reflects multiple frequencies. Light, which is a mixture of light waves that are perceived as color, such as painted objects. For example, to see a yellow light, one way is that the object directly emits yellow light; the other way is to absorb the blue part of the spectrum and reflect the red and green parts of the light. The eye is perceived as yellow.
When talking about the light associated with sunglasses, the following three types of light are important:
Direct light—Direct light is light that shines directly from your source (such as the sun) into your eyes. Excessive direct light can obscure the details of the surrounding environment and make it difficult to focus on the line of sight.
Reflected light – reflected light is often in the form of glare. The reflected light is light that is reflected back to the eye from a reflective object. Like direct light, intense reflected light makes it difficult to perceive details or look directly at an object. Snow, water, glass, and white sand are good reflective surfaces. Diffuse light—Diffuse light is light that bounces and disperses in many directions, so it seems that this light does not have a specific light source. A typical example of diffused light is the glow over a large city. It is difficult for us to determine a single source for it. When there is no direct light source, we can still see things, which is the credit of diffuse light. High-quality sunglasses eliminate UV rays in the spectrum, reduce direct light, make people feel comfortable, and eliminate or reduce reflected light (depending on the reflective surface). An interesting feature of light is polarization. When reflected from certain surfaces, such as the water surface, the light is polarized. Polarized sunglasses eliminate light reflected from water or similar reflective surfaces due to the polarized nature of the reflected light. the structuredThe dyed lensThe color of the sunglasses lens determines which parts of the spectrum the lens can absorb. Manufacturers use different colors to produce specific effectsSunglasses fruit.
1. Gray is a very good general color, which minimizes color distortion while reducing brightness. Gray lenses provide glare protection, making them ideal for driving and general use.2. Yellow or gold lenses reduce blue light while allowing more frequencies of light to pass through the lens. Because blue light can bounce and disperse a lot of light, it can produce a glare effect called blue enamel. In fact, yellow eliminates the blue portion of the spectrum, making all objects appear bright and clear. This is why snow-proof sunglasses are generally yellow. This type of color makes the color perception a bit distorted, so sunglasses of this color are not suitable for activities that require accurate color recognition.3, amber and brown are also very good general colors. They reduce glare effects, and in addition to UV, their unique molecules can absorb higher frequency colors, such as blue. Studies have shown that long-term exposure to near-ultraviolet light (such as blue and purple) is one of the causative factors of cataract. These sunglasses, like yellow lenses, cause color distortion but increase contrast and sharpness.4. The green lens can filter out some of the blue light and reduce the glare effect. Among all color lenses, green lenses offer the highest contrast and maximum sharpness, so they are popular.5. Purple and rose lenses provide the best object contrast on a green or blue background. Therefore they are a good choice for hunting and water skiing.Many sunglasses manufacturers use a process called constant density to dye the lens. This is the oldest method of making sunglasses, and the entire glass or polycarbonate blend material has the same color. Thus, in the process of manufacturing the lens, the color is inside the lens. It is also a dyeing method to plate a layer of light absorbing molecules on the surface of pure polycarbonate. The most common method of dyeing polycarbonate lenses is to soak the lenses in a special liquid containing dyeing substances so that the dyed material is slowly absorbed by the plastic. If you want to make the color darker, just extend the time the lens is soaked in the liquid.
Light waves from artificial light sources such as the sun and even light bulbs vibrate and propagate in all directions. Whether the light is transmitted, reflected, diverged, or refracted, when the light vibrates in one or more planes, we say that the light is polarized. The polarizing process can occur naturally or manually. The glare you see every time you look at the lake is an example of natural polarization. The glare reflected from the lake is the light that fails to pass through the “filter” of the lake, which is why the lake is not visible even if the lake is very clear.
Polarizing filters are typically made by placing a layer of chemical film onto a transparent plastic or glass surface. Usually, the molecules in the compound used are naturally parallel to each other. When they are evenly applied to the lens, these molecules form tiny lenses that absorb all of the light in the same direction as they are arranged.
Most of the glare that forces you to wear sunglasses comes from horizontal surfaces such as water and highways. When light reaches a surface, the reflected light is polarized with the same angle as the surface. Thus, a highly reflective horizontal surface, such as a lake surface, can produce a large amount of horizontally polarized light. Therefore, the polarizing lens of the sunglasses is fixed at an angle such that only vertically polarized light can pass through the lens. You can observe this principle by wearing polarized sunglasses and observing a horizontal surface, such as the hood of a car. Slowly tilt your head to the left or right. You will notice that the glare from this surface will brighten as your line of sight adjusts. Before you buy, you can tell the truth by doing a simple test. Look for a reflective surface, then hold the sunglasses and look at the surface with a lens. Slowly rotate the sunglasses ninety degrees to see if the reflected glare is reduced or increased. If the sunglasses are polarized sunglasses, you will see a significant reduction in glare.When the mirror of the sunglasses is exposed to the sun, the sunglasses or prescription glasses that are darker in color are called color-changing glasses. The principle of a color-changing lens relies mainly on a special chemical reaction of ultraviolet light.
The color-changing lens contains millions of molecules of certain substances, such as silver chloride or silver halide. When there is no ultraviolet light, visible light can penetrate these molecules, and visible light is a general component of artificial light sources. But when exposed to the ultraviolet light of sunlight, these molecules undergo a chemical process that changes their shape. The new molecular structure absorbs some of the visible light, which darkens the lens. The number of molecules whose shape changes will vary with the intensity of the UV light. When you come indoors and leave the ultraviolet light, the corresponding chemical inverse changes will occur. When they suddenly leave the ultraviolet light, these molecules will quickly return to their original structure, thus losing the ability to absorb light. Whether it is positive or negative, the whole process takes place very quickly.
In the 1960s, in the products produced by the manufacturers, the lenses were made of glass, and the molecules were evenly distributed throughout the lens. When using this method in prescription glasses, the problems it poses become apparent because the thickness of the different parts of the prescription lens may change, and the color may appear darker in a slightly thicker place. But with the increasing popularity of plastic lenses, people have developed a new method. By immersing the plastic lens in a chemical bath, the discolored molecules will be absorbed into the plastic lens to a depth of approximately 150 microns. This new method is significantly better than a simple coating process in which the color-changing molecules are only 5 microns thick, which does not provide enough molecules to darken the lens.reflection of mirror The lenses of reflective sunglasses can be reflected like a mirror. The lens is coated with a very thin reflective coating – it is called a semi-silvered surface because it is very sparse. The term “semi-silvered” derives from the fact that the reflective molecules on the lens are very sparse, and the number is approximately half the number of molecules that make the lens an opaque mirror. At the molecular level, the reflective molecules are evenly dispersed on the surface of the lens to form a uniform film, but only half of the area of the lens is covered by the film. This half of the silvered surface reflects about half of the light that reaches its surface, while the other half passes it directly. Typically, the mirror finish is graded and the color depth of the paint changes from top to bottom. This enhances the sun’s resistance to light from above while allowing more light to enter from below and horizontally. This means that while you are driving, the sunglasses will let you see the dashboard while blocking the sun. Sometimes, the paint is double-graded, with the highest color depth in the upper and lower parts of the lens, and the middle of the lens is clear.
The key issue with reflective sunglasses is that the paint is easily scratched. Clearly, today’s sunglasses manufacturers have not been able to successfully apply a scratch-resistant layer to the reflective film surface. Thus, the scratch-resistant layer is applied to the surface of the lens, and the reflective film is applied over the scratch-resistant layer.
Scratch protection layerThe glass is naturally scratch-resistant, but most plastics are not. To solve this problem, manufacturers have developed a series of methods to coat a transparent and strong film on the surface of the lens. Such films are composed of materials such as diamond-like carbon films and polycrystalline diamond sintered bodies. A very thin but very wear resistant film is formed on the surface of the lens by an ionization process.
Anti-reflective coating common problem with sunglasses is the appearance of glare, which is produced by light shining on the back of the lens and reflected into your eyes. The anti-reflective protective coating serves to reduce this reflection of the lens by light. With the anti-scratch protection layer as an antireflective coating layer on the lens is a very strong, thin film. The antireflective coating material has a refractive index between air and glass. This makes the intensity of the reflected light from the inner and outer surfaces of the film almost equal. When the thickness of the film is about a quarter of the wavelength of the light wave, the light reflected from the inner and outer surfaces of the film will cancel each other out by destructive interference, thereby minimizing the glare you see. An anti-reflective coating is also applied to the front surface of the refractive contact lens and some sunglasses to eliminate the “hot spots” created by the lens reflecting the intense light.UV protection contingent of the causes of some of the most serious eye diseases is: ultraviolet light. Depending on the frequency and wavelength, ultraviolet light is divided into two categories: ultraviolet A and ultraviolet B.As a natural eye protection mechanism, the cornea of the eye absorbs all UVB and most of the UVA. However, there is still a portion of the ultraviolet A that will reach the lens of the eye. Long-term absorption of UVA may cause cataracts, and a small amount of UVA that passes through the cornea to the retina can cause macular degeneration, which is the leading cause of blindness in the elderly over 65 years of age. Prolonged exposure to intense UV light can cause eye cancer or actinic keratitis, which is the burn of the retina. This is often the case when it is sunny outdoors after snowing in winter, and the snow surface reflects the sun glare, which is often referred to as snow blindness. Sunglasses have a good UV-blocking coating that eliminates UV radiation, so you must ensure that your sunglasses filter 100% of the UV rays. The label on the sunglasses should indicate what level of UV protection the sunglasses provide, and what you need is 100% protection.
Technical indicator edit Top focus deviationThe nominal apex value of the sunglasses should be 0.00D. The deviation of the lens manufacturing or the lens and the frame assembly are inconsistent.
Deviation (that is, with a positive or negative apex), if it exceeds a certain range, the wearer may feel that the object is deformed, and serious will affect the wearer’s vision health. Corresponding to the requirements of GB10810.1 “Spectacles for Spectacle Lenses Part 1: Single Light and Multifocal Lens”, the spherical lens top power tolerance is ±0.12D; the cylindrical lens top power tolerance is ±0.09D.PrismThe prism of the sunglasses should be 0.00 Δ. If the lens has a prismatic degree, the object will be transferred. If it exceeds the allowable range of the standard, it may cause the eyes to be inconsistent, or create a high level of imbalance, which will intensify the wearing. The eye muscles and optic nerves are disorderly regulated, and severe neurological disorders or strabismus may occur. According to the requirements of Table 4 of GB10810.1, the prism degree tolerance is 0.25 Δ. Light transmittance (τV)For light-colored sunglasses, the light transmittance should be >40%; for sunshades, the light transmittance range is 8% to 40%. The light transmittance project is an important indicator of the function of sunglasses. According to the current Chinese standard, sunglasses are divided into three categories: sun visors, light-colored sunglasses, and special-purpose sunglasses, while European standards and international standards divide them into five categories. The use of sunglasses is quite different in different categories. If you use light-colored sunglasses for shading, the wearer will not be able to get good results from the sunshade. For example, if the sun is strong in outdoor activities for a long time, the wearer will still feel tired due to the stimulation of strong light. Light-colored sunglasses generally play a decorative role, or in indoors where sunlight is not strong. Conversely, wearing a sun visor indoors or in a place where there is no need to block strong sunlight may cause discomfort and fatigue due to excessive enlargement of the pupil. In sunshades, products with relatively low transmission are not suitable for cyclists or motorists, because cyclists or motorists travel faster than pedestrians, and the low transmittance will affect their ability to respond.
(ultraviolet spectral region)The average transmittance is the average transmittance of the lens to the ultraviolet ray in the ultraviolet spectral range. The standard specifies a) in the UVA band of 315nm ~ 380nm, the average transmittance τSUVA should be ≤ τV;b) In the UVB band of 290 nm to 315 nm, the average transmittance τ SUVB should be ≤ 0.5 τV.In addition, in the UVB band, the average transmittance of light-colored sunglasses should be ≤ 30%, and the average transmittance of sun visors should be ≤ 5%. When sunglasses meet this requirement, the most basic requirement for protection is achieved, that is, blocking the strong light and blocking the corresponding amount of ultraviolet light. Wearing the sunglasses will at least not increase the amount of ultraviolet light received (wearing sunglasses, will Reduce the amount of light entering the human eye, causing the wearer to increase the pupil. Under the same external conditions, if the sunglasses cannot block the corresponding amount of ultraviolet light, the human eye will receive more ultraviolet light than when not wearing sunglasses. In November 2006, the officially implemented GB10810.3 “Spectacle lenses and related products Part 3: Transmittance specifications and measurement methods” clearly stipulated that the ultraviolet transmittance of sunglasses lenses should not exceed 5%. Sunglasses with UV protection are generally indicated in the following ways:a) marked “UV400”: this means that the cut-off wavelength of the lens to ultraviolet is 400nm, that is, its maximum value τmax (λ) of the spectral transmittance of the wavelength (λ) below 400nm is not more than 2%;
b) marked “UV”, “anti-ultraviolet”: this means that the cut-off wavelength of the lens to ultraviolet is 380nm, that is, its maximum value τmax (λ) of the spectral transmittance of the wavelength (λ) below 380nm is not more than 2%;
c) Label “100% UV absorption”: This means that the lens has a 100% absorption of UV light, ie its average transmittance in the UV range is no more than 0.5%. Sunglasses that meet the above requirements are sunglasses that are truly UV-protective.UV protection is an important indicator of sunglasses. Whether a pair of sunglasses has an anti-UV function, we can’t distinguish it with the naked eye. China’s current product standards have only basic requirements for UV protection, which is harmless to the wearer. The protective function is mainly made by the manufacturer to make an express promise, but not all sunglasses products have an anti-UV function. As consumers need to identify whether the product has an anti-UV function, the factory’s express commitment to the product can only be used as the sole reference.
The simulation observes the yellow and green traffic signals through the lens and the average daylight through the lens. The standard specifies that the corresponding color coordinates should be in the corresponding area in the chromaticity diagram (Figure 1). If the measured color coordinate value exceeds the specified color limit area, it will lead to confusion of various communication numbers, which is one of the hidden dangers of traffic accidents.
Traffic signal transmittanceObserve the red, yellow and green communication numbers through the lens. The standard specifies that the corresponding transmittance for the communication number is: ≥8% for the red signal; ≥6% for the yellow and green signals; Low, it reduces the ability to recognize signals, and is also one of the hidden dangers of traffic accidents.SignFor the requirements of the logo, each pair of glasses should be marked with the standard code (QB2457, etc.), category (sun visor or light-colored sunglasses, etc.) and the manufacturer’s name and trademark. The category is marked so that consumers can choose the right one according to their purpose and location when choosing sunglasses. Impact resistance lenses that are expressly protected or conform to ANSI (American National Standard), they must withstand a free fall of 16 g of steel balls from 1.27 m without breaking. This indicator is the minimum requirement for protective eyewear. If the lens is clearly protected, but it does not pass this standard, it may mislead consumers to wear a pair of glasses that they think are safe in an unsafe situation. If an accident occurs, it will directly harm the eyes of consumers.
Advantages and disadvantagesedit
advantage1, beautiful decoration2, obstructing eye defects3, can reduce the adjustment burden of the eye’s ciliary muscle under strong light4, blocking harmful light4, protect the eyes from harm5, wearing sunglasses, it looks like the face will be thin. This theory is proposed by Olsen’s sister flower. Her theory is very simple. A woman who loves beauty and loves thinness will always be “deliberate” to make herself look smaller and thinner. The bigger the sunglasses are worn on the bridge of the nose, It will make your face look smaller, creating a “face-lifting” visual effect.DisadvantageLens pictureLens picture1, the lens of poor quality is easy to cause damage to the eyes, cannot resist radiation, anti-UV, not polarized light cannot help people,2, Dai Jiu will leave scars under the bridge of the nose, 3, add weight to the ears use common sensed it
Sunglasses are not easy to wear eyelids when wearing them properly. It is not necessary to wear sunglasses when the light is dark in cloudy or indoor conditions. Some people, regardless of the occasion, regardless of the intensity of the sun, even wearing sunglasses at dusk, evening, and watching movies and television, will inevitably increase the burden of eye regulation, causing eye muscle tension and fatigue, making vision loss, visual The object is blurred, and symptoms such as dizziness and vertigo may occur in severe cases. For infants and children whose visual system is not perfect, sunglasses should not be worn. In addition to the glass sunglasses, other sunglasses lens materials are not wear-resistant, users should always pay attention to the surface of the sunglasses when the wear affects the clarity, should be replaced in time. Advantages of sunglassesBrilliant sunglasses keep you active in the sun, so free. In fact, the sunglasses can block the sun, cannot stop the pollution damage, so you should take care of it so that you can’t hold your face.The method of maintaining sunglasses is like maintaining general glasses, and it is a habit to clean, stack, and store. Only the sunglasses are often worn off, and they will be scratched if you accidentally, so there are some small details to remind you: when the sunglasses are stained, don’t use your nails to lick, it will easily scratch Surface.When the sunglasses are not worn, many people will hang them on their heads, collars or pockets. At this time, the body’s movement range should not be too large to avoid tearing or crashing. Or someone will put it in the handbag. It is recommended that you put it in a hard case and put it in the bag to avoid wearing the lens, such as a key, a comb or a copper plate or contaminated with lipstick and other cosmetics. Colliding sharp objects.
The sunglasses worn by the drivers are often placed on the dashboard or on the seats when they are not worn. This is a very bad habit. The hot weather will make the sunglasses not baked, especially the plastic frames. It is best to take off the car or collect it in the glasses. safeguard matter where you store your sunglasses, be sure to remember that the mirror is facing up.1: Folded. In the design of the frame, it is usually folded first by the left temple and then to the right.2: Pick and wear. In operation, use both hands to handle and hold the temples in the parallel direction of the cheeks.3: About cleaning. Wipe with a special eyeglass cloth. However, dry rubbing is not recommended, so it is easy to grind the lens. It is best to rinse with water, then use a paper towel to dry the water and then wipe it with a cloth. Hold the hand by hand and wipe the side of the mirror during the wiping process. The action should be light, otherwise, it will easily damage the lens and the frame. .4: Regular adjustments. After wearing for a period of time, the frame may be deformed, causing a load on the nose and ears, and the lens is also easily released. You can fix it yourself or go to the store to make adjustments.5: About placement. For a short time, the convex surface of the lens must face up, otherwise it is easy to grind, and avoid contact with various chemicals, cosmetics, medicines, etc. Also avoid direct sunlight and high temperatures. If it is placed for a long time, wrap it in a glasses case and put it in the glasses case.I hope you pay attention to the daily maintenance of sunglasses so that you can better care for sunglasses and extend the life of sunglasses.
Sunglasses are special accessories for eye care products that are designed to prevent eye damage and cause eye damage. People choose sunglasses according to different needs.However, when people buy sunglasses, they often feel uncomfortable after purchasing or have problems with the quality of their glasses. Optician experts remind the public to pay attention to the following points when purchasing sunglasses:
1. First check the quality of the lens to see if the lens surface is smooth, with or without warpage, wear marks and air bubbles. Warping of the lens can cause the line of sight to deviate, unevenness or traces, bubbles, which can cause discomfort such as dizziness. It should also be noted that the lens should not be too thin, otherwise high-temperature deformation will also cause dizziness.2, the sunglasses can be taken 45 cm from the eyes, through the glasses to observe the surrounding vertical and horizontal lines, such as window frames or door frames, and then move the glasses up and down. If the line is twisted or swayed, the lens is deformed and should not be purchased.
3. Sunglasses also have an important indicator of light transmittance, which is the ratio of the luminous flux through the lens to the incident luminous flux. It is also an important performance indicator stipulated by a mandatory standard. If you use light-colored sunglasses for shading, the wearer will not be able to obtain the effect of shading. The use of sunshades for light-colored sunglasses affects the clarity of the wearer’s vision.
4, put the sunglasses in front of the eyes, through the lens to observe distant targets, such as window frames or door frames, and then move the glasses up and down, the target should not have swing and wave deformation. It is also possible to observe the image of the tube on the surface of the lens under the fluorescent lamp, and rotate the sunglasses so that the image of the tube appears in different parts of the lens, and the image of the tube is not deformed to be optimal. Polarized sunglasses on the market, some products use a resin polarized lens with a thickness of 0.7mm. Because the lens is thin, it is easy to be deformed during assembly. Pay special attention when purchasing.
5, the color of the lens cannot be biased, the color of the surrounding environment should not be distorted. Before wearing sunglasses, observe objects such as red, green, and yellow, then put on sunglasses and observe the same object. The color of the two observations cannot be color cast, otherwise, the ability to recognize traffic lights will be reduced. For the lens is colored, especially the colorful sunglasses should pay attention to this identification.
SyndromeeditIn summer, there are more people wearing sunglasses, and some have put on myopia glasses and put them on the eyes all day long. Some young people in order to pursue fashion, sunglasses as an ornament, regardless of the occasion, the eyes are not away from the mirror, over time, the vision will be reduced, blurred vision, severe headache, dizziness, vertigo, and long-term vision, etc. symptom. Medical experts refer to the above symptoms as “sunglass syndrome.” This condition manifests itself in a variety of discomforts, such as early numbness and tingling in the area around the nose near the nose. The symptoms are more obvious when breathing, much like a cold, and others feel like a small bug crawling on the face. Walking, upper jaw numbness, upper door teeth feel uncomfortable, local blood circulation is not smooth, causing skin inflammation, eye soreness, vision loss. Physiological anatomy shows that there is a small hole under the eye called the infraorbital hole, which has an important nerve branch, the infraorbital nerve of the trigeminal nerve. It is distributed between the skin and the nose between the cracks of the eye and is responsible for the sensory function. Because of the weight of the sunglasses and the force of the mirror ring to press the underarm nerves, it will lead to discomfort in the nerve distribution area, which occurs more than 2-3 weeks after wearing sunglasses.To prevent sunglasses syndrome, one must choose and use sunglasses properly. Do not choose large frame glasses. Because such frames are mostly imported, they are designed according to the face shape of foreigners, and the distance between the double pupils of Chinese adults is mostly smaller than the optical center distance of the imported large frame glasses. Wearing such glasses will greatly increase the eyeball adjustment function. Burden, damage to vision. As for the cheap sunglasses sold on the street stalls, the production is very rough, the lenses are different in thickness, the color is not uniform, the optical performance is very poor, and it is easy to cause headache, eye pain, fatigue, and another discomfort after wearing, often wearing such inferior sunglasses. Extremely easy to cause vision loss. Second, try not to wear large sunglasses. You must shorten the wearing time when you wear it. After taking the mirror, massage the palms along the eye frame and the sides of the nose for 10-20 times. Once the symptoms of sunglasses appear, stop wearing them.
In addition, if people with myopia want to wear sunglasses, they can use glasses clip tools to wear sunglasses and myopia lenses or wear color-changing myopia glasses.
Summer is the world of sunglasses, fashion, beauty, radiation protection, these features make people prefer to wear sunglasses, but experts pointed out that when choosing sunglasses, you should be careful not to pay attention to the style, but ignore the quality of the sunglasses itself. Do not wear the following four types of unqualified sunglasses:
1, the anti-UV function name is not true sunglasses. Good sunglasses lenses can block more than 99% of UV rays, while lenses labeled with UV400 are 100% (99.99%) UV-blocking. Wearing sunglasses with poor UV protection, the eyes look like things in the darkroom. At this time, the pupils will become larger, and the residual ultraviolet rays will be injected into the eyes in large quantities, causing the eyes to be hurt. It’s best to go to a specialty store to buy it or buy it at a well-known online store or at a flagship store. Do not buy on the small stalls, although those sunglasses can block UV rays, the lens work is not in place, that is, it is not qualified, you must not buy it because of cheap, inferior glasses will cause different degrees of damage to the eyes.2. Sunglasses with unsatisfactory transmittance. After wearing such sunglasses, there will be obstacles in the identification of traffic signals, which can easily cause traffic accidents. All sunglasses include professional driving mirrors, sports mirrors, fishing mirrors … ( except for myopia and reading glasses ) The simple identification method is to place the sunglasses in front of the eyes, observe the distant targets through the lens, such as window frames or door frames, and then move the glasses up and down, the target in the field of view of the lens should not be There are oscillating and wavy deformations.
3. Sunglasses without category identification. Sunglasses are generally divided into three categories, namely sunshades for sunshades, light-colored mirrors for decoration, and special mirrors for snow-proof or waterproof plane radiation. If there is no product category identifier, the consumer cannot correctly identify the use of the sunglasses at the time of purchase, which affects the use effect.
4. Sunglasses whose performance does not meet the requirements. The lens is easily broken when subjected to an external force, and the debris can cause fatal damage to the human eye. The frame material is also very important, generally with sheet metal, aluminum-magnesium alloy, and pure titanium. The requirements for the sun are different for different needs. There are polarized motion mirrors, polarized driving mirrors, polarized fishing mirrors, etc., which are used exclusively for sports. When purchasing, you can ask about the professional use of sunglasses.
Experts remind consumers that buying sunglasses should go to the regular store to buy well-known brands; try to wear it when buying, and compare the color difference before and after wearing is obvious, the color of the object seen after wearing sunglasses is not distorted. should. What is the reason for wearing a sunglasses head? If the sunglasses have a feeling of halo, it may be caused by the tightness of the temples, the pressure of the nose pads, or the sphericity of the lenses themselves, prismatic parameters and other parameters. Regarding the multicolored phenomenon of the lens, in principle, it has nothing to do with dizziness, but it may cause poor visual effects. The reason for the multicolored may be the problem of the process when the lens is shot or the problem of the liquid. Normally, our glasses are from China’s high-end glasses professional manufacturers and are long-established Taiwanese manufacturers. Control should be good in this regard, but sometimes it may be inevitable. After all, they are all handmade. More than 8 bends of sunglasses are also a number of degrees, it may also cause dizziness. Supplement: The angle of the nose pads is mostly adjustable, and dizziness is also likely to be unqualified for sunglasses and should be stopped. The following are dizziness caused by non-quality issues:
For the first time wearing sunglasses, there will be some people who have dizziness. Generally, they can adapt after wearing for a period of time. This is mainly related to the sensitivity of the eyes;Secondly, the large-framed sunglasses have dizziness, because sunglasses have a certain degree, the greater the curvature, the greater the degree, the optical center with the degree, and the optical center distance of the large frame is larger than the pupil distance of the human eye. When some people wear it, they will feel dizzy.There is also glaucoma wearing sunglasses will also dizzy, here will not explain in detail, the specific reasons can consult the local doctor.
When the light is dark, wear sunglasses. The sunglasses themselves have the effect of weakening the light. At this time, wearing sunglasses will cause eye pressure to rise and cause dizziness.[ Expert reminder ]
Children under the age of 6 are also not suitable for wearing sunglasses for a long time, because their visual function development is not up to adult level, wearing sunglasses for a long time may form amblyopia.
Shopping points edit With the advent of summer, consumers who choose sunglasses and myopia glasses are gradually increasing. In order to enable people to purchase a pair of qualified and comfortable glasses, experts will remind consumers to pay attention to many aspects when choosing glasses. : First, we must pay attention to the optometry. Choosing a pair of suitable, comfortable glasses, accurate optometry is a fundamental factor. Before fitting glasses, check the optical shop optometry staff, whether they have the optometrist or optometry certificate issued by the provincial glasses industry association; if the optometry is affected by emotions and physical conditions, it should be optometry twice in a few days. Achieve scientific and accurate optometry results.
The second is to pay attention to the material selection of glasses. Generally, the spectacle lenses are divided into resin, glass, and crystal, and the lenses and frames should have a shelf life. If the lens and frame are imported materials, there should be a certificate of importer inspection. Third, when purchasing glasses, be sure to see the product quality inspection certificate, the name of the manufacturer and the site of the purchased glasses. At the same time, you must obtain the purchase invoice. Once the quality problem occurs, you can protect your legal rights. Four: sunglasses have a polarizing effect, and anti-ultraviolet effect, pay attention to whether the sunglasses lens meets the international standard UV400 if the lens does not reach UV400 is unqualified.QualifiededitIt is necessary to be able to filter out more than 99% of the ultraviolet rays in the sun. In addition, it is a function of blocking glare, and it is especially important that dark lenses do not cause “parallax” and “color difference”. “Parallax” is a matter of walking after reading glasses, objects are twisted, and stairs are up and down. When the “color difference” is serious, the red and green lights will be unclear and cause danger. The surface treatment of the lens, refractive, curvature and safety enhancement are also essential for eye protection and eye protection. health knowledge edit1. Yellow lens, filter 100% UV light clearing agentYellow lens sunglasses are 100% UV-filtered, allowing infrared and 83% visible light to penetrate the lens. Its biggest feature is that it can filter most of the blue light under the sun. When the sun passes through the atmosphere, it mostly appears as a blue light, which is why you see the sky is blue. After the yellow lens filters the blue light, the natural scenery can be seen more clearly. Therefore, wearing yellow lens sunglasses while driving, you can see the traffic more clearly.2. Green lens, filter 99% UV comfort sedative
The stylish green lens, like the grey lens, filters infrared light and filters 99% of the UV light. However, the green lens will change the color of some scenes, and the effect of blocking light is slightly inferior to that of gray lenses. Fortunately, green is a natural calming agent that can make your mood around you feel comfortable. If you want to be a “love ambassador”, you can wear green lens sunglasses to make the surrounding noises quiet for you.
3. Gray lens, filter 98% UV shading penetrantGray lens sunglasses filter almost the same amount of light in the sun and can filter infrared rays and 98% of ultraviolet light. Wearing gray lens sunglasses, the original color of the scene will not change due to the lens, but also to block the glare. In hot Malaysia, grey lenses are praised by local experts as “the most comfortable sunglasses.” When wearing outdoor activities in the summer, wear gray lens sunglasses, not only pull the wind, shade but also see the most beautiful colors.4. Pink lens, filter 95% UV strong confidence agent
Pink lens sunglasses that filter 95% of the UV rays and some shorter wavelengths of visible light. In fact, the pink lens is similar to the general uncolored lens and does not have better protection than the general lens.
But psychological research found that 65% of women wearing pink lens sunglasses, confidence is 15% higher than usual. Pink sunglasses are purely your psychological placebo and can be worn on a rainy day with a feeling of boredom or UV. Choose the wrong sunglasses, look for you with your eyesChoosing the wrong sunglasses, in addition to the eyes will suffer, even the body may be out of tune. If your body has the following symptoms, you should change your sunglasses immediately. Trouble 1: Sunglasses are too heavy, headaches burst into burstsAmerican ophthalmologists say that once the weight of sunglasses exceeds 45 grams, it will overstress the temples, straining the brain and causing intermittent headaches. This is the most common type of “sunglass syndrome.” If you feel that your headache is always wearing sunglasses, it will disappear automatically within half an hour after removal. It is best to replace a pair of lightweight and compact sunglasses immediately.
Trouble 2: The lens holder is too tight, and the toothache is also numb. Sunglasses have been worn for a long time. If you feel that the upper jaw is numb and the upper door is sore, it is likely that the two lens holders are too tight. Go to the optical shop and ask someone to loosen the lens holder or change a pair of comfortable wide-brimmed glasses. A survey by German ophthalmologists found that the initial performance of the lens holder is that there is mild numbness between the eyelids or the cheeks, and nasal discomfort during breathing. After 2 hours or longer, the pain will gradually spread to the mouth, making you have a toothache.
Trouble 3: The lens is too dark and the eyes are super fatigued The British Association of Ophthalmology Research found that 13% of vision loss is related to the color of sunglasses lenses. If your eyes are dark black, you have better UV resistance than those with light brown and blue-brown eyes. At this time, you choose dark purple or pure black sunglasses, your eyes will be too tired, and the vision will decline due to long-term. Korean ophthalmologists say that the most suitable lenses for oriental women’s dark eyes are light gray and light red.
Maintenance knowledge edit1. When wearing glasses, please hold the temples with both hands and remove them from the front. If you wear glasses with one hand, it is easy to cause deformation and looseness.
2. When not in use, wrap it with a mirror cloth. The lens is facing up and placed in a special bag. Be careful to prevent the lens and frame from being scratched by hard objects.
3. The frame or lens is contaminated with dust, sweat, grease, cosmetics, etc. Please use a mild detergent to clean the water, then use a soft cloth to dry.
4. It is forbidden to be exposed to water for a long time, soaked in water and placed in a fixed place to be exposed to sunlight; it is forbidden to be placed on current and metal for a long time. 5. Please fold the left temple before receiving the mirror. 6. The glasses frame is distorted and drooped. When used again, the lens clarity will be affected. Please go to the store for free adjustment. 7. After the plate sunglasses are used for a period of time, there may be a slight deformation. This is normal. You can go to the store to adjust the frame. 8. Sensitive color-changing mirror Please do not leave it in a place with strong light for a long time, otherwise, it will shorten the use time of the color-changing effect, but if the photosensitive color is gradually lost due to long-term wear, it will not change the polarizing effect. Please feel free to use it. .Not suitable for the crowdeditglaucoma When the sunglasses are worn, the visible light entering the eye is reduced and the pupils are naturally enlarged. This change of pupil has no effect on healthy people, but for glaucoma patients, it increases the barrier of aqueous circulation in the eye, which can easily induce acute episodes of glaucoma, redness, eye pain, headache, nausea, vomiting, and a sharp decline in vision. And other symptoms. Therefore, glaucoma patients or suspected glaucoma, do not wear sunglasses.
Color blindness Wearing full-color blinds does not have much impact. However, some color-blind patients have a lack of discrimination in several colors, and they are even more incapable of distinguishing colors when wearing sunglasses. Night blindnessNight blindness is caused by a lack of vitamin A , which causes vision to be affected in dim light. Therefore, sunglasses will affect the vision of people with night blindness.RetinitisWearing sunglasses can aggravate the optic nerve conduction disorder in patients with optic nerve retinitis and affect the recovery of the disease.childThe visual function of children under the age of six has not yet reached normal levels. The New Vision Eye Hospital said that if you wear sunglasses for a long time, it will affect the child’s visual development. It can even lead to amblyopia.Distinguish from polarizereditToday’s UV-resistant glasses are usually divided into sunglasses and polarizers. Sunglasses are commonly used to cover sunlight and ultraviolet light. In people’s daily life, in addition to the sun and ultraviolet light, when there is light in the uneven road, water, and other places, there will be irregular light, which is commonly called “glare.” The appearance of glare will make your eyes uncomfortable and affect the clarity of the object. The polarizer is a sunglasses that can effectively remove glare.
It is understood that a small part of the purchase of polarizers is a customer who needs to ride a bicycle. There are many types of polarizers on the market, the colors are mainly dark gray and green, and the general brands also have stylish white and bright yellow.
1. There are many ways to distinguish polarizers. One of the simple ones is: the two polarized lenses are stacked vertically, and the lens will show no light transmission. The reason is that the polarized lenses are specially designed to only be flat. When the two lenses are stacked vertically, the light is blocked. When you are purchasing, you only need to do a simple operation, you can immediately know the authenticity of the product and the good.”
2, “At the same time, there will be a discriminating board that distinguishes the polarized light mirrors. The naked eyes look up with black stripes, but with a polarizer on it, you can see the black color that you can see in the naked eye! can be seen! Driving at night editThe probability of a traffic accident at night is 1.5 times greater than during the day, and 60% of major traffic deaths accident occurred at night. When driving at night, the flashing surveillance shooting on the high beam and on the road can cause strong irritation or even damage to the human eye. When the human eye is stimulated by the strong light of the headlights, the pupil automatically shrinks from the normal 5~8 mm to 1 mm or less, so that the amount of light entering is reduced to 1/16 or more, and the car will not be able to recover after the car. The sudden decrease in light volume and the phenomenon of night blindness occur, and many traffic accidents occur .The human eye is very resistant to strong light exposure, and the illumination of strong light is often dozens of times the tolerance of the human eye. Due to the polymerization of the light by the eye, the intensity of the strong beam penetrating the eyeball to the retina is hundreds or even thousands of times greater than reaching the cornea.  Night driving safety solution 1 Ordinary sunglasses or color-changing mirror: It is only suitable for wearing during the day. Driving at night will seriously affect the field of view (the national standard requires that the light transmittance of driving glasses at night must be >75%). The transmittance of general sunglasses does not meet the requirements.  Light yellow driving mirror has a bad light blocking effect
Light yellow driving mirror light blocking effect is not good (2 photos)2 ordinary light yellow night driving mirror and gradient color all-weather driving mirror: ordinary light yellow night vision mirror can only block 20-30% strong light blocking is not enough; all-weather driving mirror can weaken strong light, but the visual field darkening affects road safety, the same Does not meet the national standards for night driving glasses  .
3 light barrier, dimming strip and night vision treasure: This kind of dimming object placed on the front glass will block part of the field of vision in front of the driver, forming a blind spot of the field of view. Moreover, this kind of obstruction is with the car body. The driver’s constant bumps and shaking in the eyes will cause headaches, dizziness, and nausea, and some products are fragile and unsafe  .A good night driving mirror should be able to block more than 80% of the glare of the other car, and the transmittance of the main lens must be >75%. Observing the road is not affected. Wearing a good driving night vision goggle at night can ensure the driver’s Driving safety. 
Sunglasses are not used to block sunlight when they first appear. In 1752, James Ayscough made glasses for the first time with green or blue colored lenses. Although the descendants respected him as the ancestor of sunglasses, he only thought that this design could improve people’s visual problems. According to the “Return to the Mind” written by Liu Wei in the 12th century, the official people of China at that time also wore “sunglasses”, which were made of smoky quartz, not to cover the glare of the sun. Instead, when listening to the confession, let others not see his reaction. It seems that the function of sunglasses at the beginning of the invention is quite different from that of sunshade and fashion.With the rise of the second technological revolution, the sunshade and eye protection functions of sunglasses have become more apparent. The mass production of cars and the use of aircraft have enabled sunglasses to enter the public eye. At that time, almost all of the planes were open-top. In order to shield the strong sand and the glare of the sun, the sunglasses were designed with more emphasis on shading and eye protection, and gradually became one of the essential items for the pilot.
Initially, this newly invented sunglasses was just the pilot’s goggles. Later, people found that it not only absorbs sunlight but also has very little heat energy. It also has a protective effect on vision, and it is gradually being promoted in the US military. As a result, the handsome appearance, the neat military uniform, and the handsome wind-proof sunglasses made the American soldiers become the Prince Charming in the hearts of countless girls. During World War II, the US five-star general, General MacArthur, was wearing sunglasses. His image of wearing a pipe and wearing sunglasses was deeply rooted in people’s hearts. People’s love for heroes also loved the house and the generals’ sunglasses.
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