Transmittance is the fundamental functional requirement of glasses. For cheap eyeglasses near me lenses, transmittance generally refers to the visible light transmittance ratio.
Simply put, due to the varying sensitivity of the human eye to different colors of light, when evaluating the light transmittance of lenses, the distribution of the light source spectrum should be considered, which can be understood as the distribution of various color components inside the light source.
Visible light needs to enter the eyes through cheap eyeglasses near me lenses to see clearly, so for most people, the higher the visible light transmittance, the better. The first purpose of optical coating on lenses is to increase transmittance.
But what factors can affect the transmittance of lenses? Light passing through the front and rear surfaces of the lens will be reflected, and it will be scattered by opaque materials inside the lens. The lens material will also absorb some of the light, and the remaining light will reach the eye through the lens.
The technology and process requirements for optical coating are very high, and the higher the refractive index of the lens substrate, the higher the process requirements.
When choosing eyeglasses online cheap lenses, it is important to pay attention to the reflection of the optical coating. The brighter the reflection, the lower the overall transmittance.
Of course, this is a very intuitive feeling. Who knows how dazzling it will be when buying lenses? Due to the fact that some lenses claim to have anti anti-blue light function, the design requirement for anti-blue light is to filter out some blue light. As blue light is visible light, it will inevitably affect the visible light transmittance. It is normal for the transmittance of anti-blue light lenses to be relatively low.