Because the price of a blue-light-blocking lens is much higher than that of common lenses, and its profit margin is relatively high, so in the process of matching glasses, the price of blue-light-blocking glasses is different. So how are blue-light-blocking glasses tested and differentiated?
Look at the lens
High-quality anti-blue glasses do not interfere with the line of sight, with high transmittance. The light transmittance is very high, and the visual clarity is higher, which does not affect the visual quality, quality of life, contrast sensitivity, and color discrimination.
The membrane layer of the lens
Blue light-blocking glasses have many membrane layers, and all kinds of colors of the film are not the same. Actually, the membrane layer of anti-radiation effects is not large but has high strength and chemical resistance of lining norm of glasses and the effect of protection for the eyes is very important.
The screen test
When the glasses are placed in front of a display screen or watched in the environment with LED light, the blue-light-blocking lenses reflect blue lights, while the non-anti-blue lenses do not reflect blue lights. Of course, there are a small number of blue-blocking glasses that reflect green lights.
Check the specs
Blue-light-blocking lenses are now focused on refractive indices of 1.56 and 1.60. If you buy lenses that are not of either refractive index, be wary. Of course, with the development of technology, now some brands have produced 1.71 refractive indexes blue-light-blocking lenses, suitable for people with high myopia to wear. The true lens package should at least have the product name, refractive index, dispersion coefficient, transmittance, color, SPH, CYL, and other indicators. These indicators are perfect, can be treated as the reference basis of the formal product. In addition, you can go to a professional optical shop or testing institutions for testing.
