Polarized sunglasses are a type of sunglasses. Polarized light can be divided into three types, namely linear polarized light, elliptical polarized light and circular polarized light. Generally the so-called polarized light refers to linear polarized light, also known as plane polarized light. The vibration of this light wave is fixed along a specific direction, the propagation path in space is a sinusoid, and the projection on the plane perpendicular to the propagation direction is a straight line.
The plane composed of the vibration direction and the propagation direction of linearly polarized light is called the vibration plane, and the plane perpendicular to the vibration direction and containing the propagation direction is called the polarization plane. Linearly polarized light can be obtained by passing natural light through a polarizer, which is often used in crystal optics research.
The types of polarized sunglasses are divided into: linear polarized, elliptical polarized and circular polarized polarized light refers to linear polarized light
▪ Definition
▪ Function
▪ Production principle
▪ Identification
▪ Degree of UV protection
▪ Polarized light
▪ Difference
▪ Classification
▪ Application
Definition
Polarized light, visible light is a transverse wave, and its vibration direction is perpendicular to the direction of propagation. The vibration direction of natural light is arbitrary in the plane perpendicular to the propagation direction; for polarized light, its vibration direction is limited to a specific direction at a certain moment.
Function
Polarized sunglasses
In life, too many light sources can produce harmful light, especially sunlight; the light emitted from the sunlight includes three types: visible light, infrared light, and ultraviolet light. Among them, ultraviolet rays cause serious damage to human skin, eyes, etc.; on the sun, visible light (380~780nm); ultraviolet rays are divided into UVA, UVB, UVC (310nm) and above, of which UVA, UVB, UVC are harmful Light, if exposed to the sun for a long time, it will cause damage to the body. UVB has a serious impact on eyesight. Tanning Ray is the light that burns the skin. Most of the corners of the eyes will absorb this UVB light, so this light source must be blocked. Polarized sunglasses have the function of polarizing light, so they can block all harmful light without affecting the transmission of visible light, which can truly protect the eyes. In addition to basic anti-ultraviolet functions, polarized sunglasses also have anti-glare, reflected light on the road, and scales on the water surface. They are suitable for driving, fishing, traveling, and daily wear.
Production principle
Polarized sunglasses can block uncomfortable glare, while protecting the eyes from ultraviolet rays. All of this is due to the metal powder filter device, which can “select” the light when it hits it. Polarized sunglasses can selectively absorb some of the wavelengths that make up the sun’s rays because they use very fine metal powders (iron, copper, nickel, etc.). In fact, when light hits the lens, the light is reduced based on the so-called “destructive interference” process. In other words, when certain wavelengths of light (herein referred to as ultraviolet a, ultraviolet b, and sometimes infrared) pass through the lens, they will cancel each other out on the inside of the lens, that is, toward the eye. The overlapping of light waves is not accidental: the peaks of one wave and the troughs of the adjacent waves combine to cancel each other. The phenomenon of destructive interference depends on the refractive index of the lens (that is, the degree of deviation when light passes through different substances in the air), and it also depends on the thickness of the lens. Generally speaking, the thickness of the lens does not change much, and the refractive index of the lens varies according to the difference in chemical composition.
Polarized sunglasses provide another mechanism to protect the eyes. The reflected light from the asphalt road is a relatively special polarized light. The difference between this reflected light and the light directly from the sun or any artificial light source lies in the problem of order. Polarized light is formed by waves that vibrate in one direction, while ordinary light is formed by waves that vibrate in non-directional directions. It is like a group of people walking in disorder and a group of soldiers marching in order, forming a sharp contrast. Generally speaking, reflected light is an orderly light. Polarized lenses are particularly effective in blocking this light because of their filtering properties. This kind of lens allows only polarized waves that vibrate in a certain direction to pass through, just like “combing” the light. For road reflection problems, the use of polarized sunglasses can reduce light transmission, because it does not let light waves that vibrate parallel to the road pass. In fact, the long molecules of the filter layer are oriented in the horizontal direction and can absorb horizontally polarized light. In this way, most of the reflected light is eliminated, and the overall illuminance of the surrounding environment is not reduced.
Finally, the lenses of polarized sunglasses can darken after the sun’s rays hit. When the lighting diminished, it became bright again. This is possible because the silver halide crystals are working. Under normal circumstances, it can keep the lens perfect transparency. Under the sunlight, the silver in the crystal separates, and the free silver forms small aggregates inside the lens. These small silver aggregates are in the form of irregular lumps with canine teeth. They cannot transmit light, but can only absorb light. As a result, the lens darkens. In the dark, the crystal re-forms, and the lens returns to its bright state.
Identify
Degree of UV protection
The meaning of the UV standard refers to: the human eye’s perception of light is 380~780nm (that is, visible light), and ultraviolet light refers to light with a wavelength below 380nm (invisible light). The meaning of UV380 is that it can effectively block light with a wavelength below 380nm. The UV400 standard also blocks part of the visible light at the same time, so part of the color will be lost.
The color saturation of the polarized light makes the contour of the object blurred and makes the eyes tired and uncomfortable. The polarizer is made according to the polarization principle of light, that is, when the vibration plane of the light is parallel to the polarization axis, the polarized light filter can transmit the polarized light (like the principle of louver). Therefore, the light is arranged into the same direction light to enter the human eye, so that the surrounding scenery looks clear and not dazzling. In addition, another outstanding advantage is that the lens is extremely light, extremely thin (thickness 0.8mm, 1.1mm) and impact resistant, so this kind of lens is very suitable for driving and outdoor activities, and has been favored in recent years. Drivers prefer to wear polarized sunglasses, because in addition to blocking ultraviolet rays, polarizers can also minimize and filter out the reflected glare. For example, the strong light of the opposite car while driving, or the strong glare formed by the reflective and UV-blocking window film on the rear window of the driving car being irradiated by the sun, so that the wearer can clearly see what is ahead.
The difference
Normal sunglasses only use the effect of light reduction, because ordinary lenses cannot filter light, so they can only reduce the intensity of glare, ultraviolet light, etc., and cannot completely block these harmful rays, so their function is only to reduce eye damage, but the general sun The biggest advantage of glasses is their popularity. Polarized lenses have polarizing properties, so they can completely block the dazzling glare caused by various factors such as scattering, refraction, and reflection. At the same time, it can completely block the ultraviolet rays that are harmful to human eyes, so that when people are active under strong light for a long time, the eyes are not easy to get tired, to achieve the function of real protection, and to see things more clearly and three-dimensionally.
Classification
Polarized sunglasses can be divided into riding glasses, ski goggles, fishing glasses, polarized driving glasses, outdoor sports glasses, and golf glasses.
Polarized sunglasses can be divided into polarized sunglasses made of glass, polarized sunglasses made of resin, and polarized sunglasses made of TAC lenses.
application
In summer, fishing friends like to wear polarized glasses. Why? The reason is simple. Polarized sunglasses have the function of filtering polarized light. If you wear them for fishing, it is easier to see drifting and your eyes are not tired. If the lenses are dark in color (such as brown, green and gray, etc.), they can be used in summer. It feels more comfortable to wear.
Polarized lenses are globally recognized as the most suitable lenses for driving. When the light is reflected from the surface of the object, it has been partially polarized to produce glare. The opposite effect of glare—enhance brightness and weaken color saturation; make the contours of objects blurred and make the glasses tired and uncomfortable. The polarizer is made according to the polarization principle of light, and has the special function of effectively eliminating glare, filtering out the chaotic light, so that the driver can improve the vision and increase the driving pleasure.
Friends who love outdoor leisure travel also have a soft spot for polarized lenses. Polarized lenses are composed of a balanced arrangement of crystals. This structure allows only light waves balanced with the crystal to pass through, and light waves vibrating at other angles are uniformly blocked. If you adjust the angle of the polarizer, the polarized light reflected from water, glass, flowers, and moisture can be blocked, and normal light can be partially passed through, thereby enhancing the contrast, reducing reflections, enhancing the color of the scene, and reducing the atmosphere. The effect of the fog phenomenon allows you to see the clarity of the world and give you a colorful world, a bluer sky, and a rich and beautiful nature.
The polarized angle and radian of the lens are professionally designed and processed, so that the wearer will not feel distorted and dizzy. The resin polarized lens has the advantages of lightness and resistance to breakage, and it is easy and comfortable to wear. Most suitable for fishing, driving, sports, sailing, skiing, hunting and other occasions.
This article is from Baiyu Sunglasses Factory
