What is a polarized sunglasses?
Also called polarized light. Visible light is a transverse wave, the vibration direction perpendicular to the direction of propagation. The vibration direction of natural light, in the vertical plane in the direction of propagation is arbitrary; For polarized light, the direction of vibration in a certain moment, are limited in a particular direction.
polarization can be divided into three kinds, namely linear polarized light, ellipse polarized light and circular polarized light. General so-called polarization refers to the linear polarized light, also called plane polarized light. The vibration of the waves along the direction of a specific fixed, in the space of the transmission line as the sine curve, in the vertical direction the plane for a straight line. Linear polarization direction and the direction of propagation of vibration plane is called the vibration plane, and the vertical direction of vibration and contains surface in the direction of propagation is called polarization plane. Take the natural light through the polarizer, linear polarized light can be obtained, is often used in the study of crystal optics.
polarized sunglasses function in the life, there is a lot of light source can produce harmful light, especially sunlight; The sun give off light has: visible light, infrared, ultraviolet, 紫外线) Such as three. With ultraviolet radiation to the human body of skin, eyes, etc. , cause serious damage; In the light of IR (released by the sun is 下文, 红色) Infrared ( 750海里) Above, visible light, 可见光线) ( 310 ~ 780海里) ; Is divided into UVA, UVB and UVC ( 310nm） Above, green light ( 蓝灯) Which is harmful UVA, UVB and UVC light, if long time exposure can cause damage to the body, UVB is has a serious effect on vision, 晒黑雷) Is burned black light, most of the canthus can absorb the UVB light, so be sure to block out the light.
polarized sunglasses because has the function of the polarization of light, so can all the harmful rays of block off but does not affect the visible light through, can truly achieve the purpose of protecting our eyes. Polarized sunglasses in addition to the basic uv protection function, but also has anti glare, pavement reflect light, the surface scales such as light, suitable for driving, fishing, travel, daily wear.
as the sun glasses with polarized sunglasses compared commonly
general sun glasses is just use the function of reducing light, because the general lens can't filter the light, so can reduce glare and uv light intensity, and can not completely block the harmful rays, so its function is to reduce eye damage, but generally the sun glasses is the advantage of big epidemic. Polarized lenses are due to have polarized nature, so can be completely cut off because of scattering, inflectional, such as reflection and dazzling glare caused by various factors. And at the same time for the human eye can be harmful ultraviolet light is completely cut off, make the person is in long-term activities under strong light, the eye is not easy to tired, achieve real protection function, and to see things more clearly, three-dimensional.