To change color lenses standard parsing

First of all, the photochromic lenses to conform to the quality of the lens testing, such as: standard GB10810 - Specified test conditions for 2005 ( 23±5) ℃( Mainly suitable for measuring the optical parameters) , the standard rules on the flash lens optical, surface quality and geometric features, in the implementation of 96 version of the standard, need to have a thorough understanding of the term in the standard. In addition, because of the photochromic lenses have its special optical properties, therefore, in the process of detection, attention should be paid to the following aspects: 1. Discoloration speed and fade fading and discoloration speed is the main indicators of quality color glasses. The detection of a pair of color glasses, the first thing to check the lens discoloration speed, second, the method is in the ultraviolet ( The sun) After irradiation, the observation after how much time can completely change color; Leave after uv irradiation, under normal temperature, how long can fade and translucent level, which looks down to the weak light environment lens had a light time, generally 2 min can return to original state, and in the lens f. After completely faded, check the lens surface is; No colorless, transparent, don't leave any color. In general, put the lens in the sun light more than 1 min, lens light transmittance can to a large value of more than 80%; When the lens from the sun into the interior 2 min, light transmittance lens is a reply to the 609 'above, shows the photochromic lens technology is relatively mature, become angry so fast that the lens of color changing faster than the eyes to adapt to the speed of light, but not the lens discoloration speed is indicated that the lens is a good lens, too fast may even be dangerous, driving a car with the lens if it is can change color, is not very ideal, because the human eye takes a few seconds of time to adapt to the change of illumination conditions, if the time of the photochromic lenses darker and eyes close time to adapt to changes in light, is the ideal ratio. Photochromic lens discoloration ability is related to its own color factor, under the light, color changing factorization to have color of silver and other elements, in the absence of light, after the decomposition of silver and other elements to no color change color factor, it is also a photochromic lens color and back color ability the key to fast and slow. In addition, the color change process of the photochromic lenses happened inside the lens itself, is the change process of molecules and atoms. 2. Color tonal uniformity change color after whether the color of the uniform is symmetrical, the depth of the color associated with the lens when the temperature of the heat treatment and the use of temperature, therefore, be sure to check whether change color tone after evenly in the sun - , cause, there is the emergence of the light stripe, namely after lens discoloration, a mirror, a don't change color white stripes, make the specular color uneven, encountered such a situation, shows the photochromic lenses have quality problem, need to timely replacement lenses. Around at the same time, to observe the two lenses, in the same luminosity, whether change color after color depth is the same, if there is a deep color, a shallow, discoloration or a piece for a color, the other one for the other colors, is not a qualified photochromic lenses, a phenomenon known as 'mandarin duck'. Here to special emphasis on 'yuanyang' colorless transparent indoors is found not wrong, only in the sunlight, can find its problem, so when testing the photochromic lenses must be under the irradiation of light test standard. Photochromic lenses for light intensity of different and different, the stronger the light, the deeper the color, is mainly to light absorption effect, uniform color, reduce the color distortion, must be in accordance with the provisions of the state of the traffic signal recognition project than. The photochromic lenses. Is a kind of when encounter uv irradiation, by Yu Guanghua reaction as a result, photosensitive color factor in active activities, rearrange the combination after absorption of visible light, led to the lens color is darker, as uv vanish, light-sensitive factor back to the original state, the lens back color, so the photochromic lenses color changing effect is related to the intensity of the ultraviolet ray, photochromic lenses provide suitable ultraviolet eyes and dazzle eye protection, according to the light in a timely manner to adjust the color of the lens, at the same time of protecting eyesight, provides better health for eye protection. 3. Lens light transmittance of any color lens should be able to return to 60% ~ 70% in the retreated inside a few seconds of light transmittance, in about 15 ~ 20 min 85% light transmittance. In the face of strong light, our eyes need to make the adjustment of the hundreds of times to adapt to the change of light, it can lead to the human eye fatigue and soreness, photochromic lenses through control the amount of the human eye light, automatically reduces the wearer's body, such as strabismus, eye muscle. Photochromic light transmittance for the lens will reduce after dark, but reflected light remains on the surface of the lens, so by the lens of concave surface of the reflected light and lens before and after the 'ghost' generated by internal reflection and glare may interfere with vision, still affect Dai Jingzhe vision clarity and comfort. Coated minus reflection membrane, therefore, the photochromic lenses than no minus reflection film plating glasses, can improve the comfort and safety of Dai Jingzhe. 4. Ultraviolet prevention function of uv protection effect, should conform to the state of the average transmittance, changed the lens in the process of production are added a certain amount of ultraviolet absorbent, so this kind of lens itself also has the function of uv protection, plus color dyes mainly by absorbing uv discoloration, therefore, discoloration uv protection function of the lens is generally better.