The completion of finish photochromic blended lenses must meet the quality inspection of spectacle lenses. For example, the test conditions specified in the standard GB10810-2005 are (23±5)°C (mainly applicable to the measurement of various optical parameters). The standard specifies the For the requirements of optics, surface quality, and geometric characteristics, when implementing the 96th edition of the standard, a thorough understanding of the terms in the standard is required.

In addition, due to the special optical properties of the completed photochromic hybrid lens, the following aspects should be paid attention to during the inspection process :

1. Color change speed and fade speed

The speed of discoloration and the speed of discoloration are the main indicators to measure the quality of color-changing glasses. When inspecting a pair of color-changing lenses, first check the discoloration speed of the spectacle lens. Second, the method is to observe how long the color can be completely changed after ultraviolet (sunlight) exposure; after leaving the ultraviolet radiation, at normal temperature, more It can fade for a long time and reach the degree of translucency, that is, observe the time when the lens is lightened when moved to a low-light environment. Generally, it can be restored to the original state in 2 minutes, and after the lens f. is completely faded, check the surface of the lens; The color is transparent, leaving no color. Generally, if the lens is exposed to sunlight for more than 1 minute, the transmittance of the lens can be reduced to more than 80% of the maximum value; when the lens is placed indoors from the sun for 2 minutes, the transmittance of the lens is It reverts to above 609, which shows that the technology of this photochromic lens is relatively mature, the discoloration speed is extremely fast, the discoloration speed of the lens is faster than the speed of the eye to adapt to light, but it does not mean that the lens discoloration speed is fast. Good lenses, too fast, may even be dangerous. If the lenses used for driving can change color, it is not ideal, because the human eye needs a few seconds to adapt to changes in light conditions. If the photochromic lens changes The deep time is particularly close to the time the eyes adapt to changes in light, which is a very ideal ratio. The color change ability of photochromic lens is related to its own color change factor. Under light, the color change factor is decomposed into colored silver and other elements. In the absence of light, the decomposed silver and other elements are recombined into There is no color change factor, which is also the key to the fast and slow ability of photochromic lenses to change color and recolor. In addition, the discoloration process of the photochromic lens takes place inside the lens itself, which is the transformation process of molecules and atoms.

2. Color uniformity after color change

Whether the color after discoloration is uniform and symmetrical, the depth of the discoloration is related to the heat treatment temperature of the lens and the temperature during use. Therefore, it is necessary to check whether the color tone is uniform after the discoloration in the sun, and whether there are insensitive stripes, that is, after the lens is discolored , A white stripe that does not change color appears on the mirror surface, which makes the mirror tone uneven. In this case, it means that the photochromic lens has quality problems and needs to be replaced in time. At the same time, observe the two lenses on the left and right, under the same luminosity, whether the color is the same after the color change. If there is a dark color change, one light color change, or one color and the other color, it is not a pair Qualified photochromic lenses, this phenomenon is called "mandarin duck lens". It should be particularly emphasized here that the "mandarin duck film" is colorless and transparent indoors, and there is no problem. It is only found under sunlight. Therefore, when testing the photochromic lens, it must be in the light. The standard test is carried out under the irradiation. The photochromic lens varies with the intensity of light. The stronger the light, the deeper the discoloration. The main reason is the absorption of light, uniform color, and reduced color distortion. It needs to meet the national traffic signal identification projection ratio. Photochromic lens. It is a kind of photochromic factor that absorbs visible light and rearranges and combines when exposed to ultraviolet rays as a result of the photochemical reaction, which causes the lens to darken. When the ultraviolet rays disappear, The photosensitive factor returns to its original state and the lens returns to its original color. Therefore, the discoloration effect of the photochromic lens is related to the intensity of ultraviolet light. The photochromic lens can provide suitable UV and dazzling protection for the eyes. The color of the lens can be adjusted in time according to the light to protect the eyesight At the same time, it provides better health protection for the eyes.

3. The transmittance of the lens

Any color-changing lens should be able to return to 60%～70% light transmittance in a few seconds, and reach 85% light transmittance in about 15-20 minutes. When facing strong light, our eyes need to make hundreds of adjustments to adapt to changes in light, all of which will cause eye fatigue and soreness. The photochromic lens automatically reduces the amount of light from the human eye by controlling the right amount of light. Wearers such as strabismus, eye muscle strain. The light transmittance of photochromic will decrease due to the darkening of the lens, but the reflected light on the surface of the lens still exists, so the "ghost" and flare produced by the reflection of the concave surface of the lens and the internal reflection of the front and back surfaces of the lens will still be affected. Interfering with vision, affecting the clarity and comfort of the wearer's vision. Therefore, the photochromic lens coated with anti-reflection coating can improve the comfort and safety of the wearer compared with the lens without anti-reflection coating.

4. UV protection function

The anti-ultraviolet effect should be in line with the national average transmittance. A certain amount of ultraviolet absorber is added to the color-changing lens during the production process, so the lens itself also has anti-ultraviolet function, and the color-changing dye mainly changes color by absorbing ultraviolet rays. Therefore, the UV protection function of the color changing lens is generally better.