Middle Index 1.56 Semi Finished Progressive Photo Grey Blue Block Hc Optical Lenses

Lens: A piece of glass or other transparent material with one or more curved surfaces through which objects appear clear, larger, or smaller. Usually used in glasses, cameras, telescopes, etc
Classification: Lenses can be divided into the following five types according to different materials:
Resin lens special lens space lens glass lens PVC lens
The index of refraction refers to the refractive index of the lens, and the higher the index, the thinner the lens. Refractive index generally: 1.49, 1.56, 1.61, 1.67, 1.74.

What Is Blue Light?

Sunlight contains red, orange, yellow, green and blue light rays and many shades of each of these colors, depending on the energy and wavelength of the individual rays (also called electromagnetic radiation). Combined, this spectrum of colored light rays creates what we call "white light" or sunlight.
Without getting into complicated physics, there is an inverse relationship between the wavelength of light rays and the amount of energy they contain. Light rays that have relatively long wavelengths contain less energy, and those with short wavelengths have more energy.
Rays on the red end of the visible light spectrum have longer wavelengths and, therefore, less energy. Rays on the blue end of the spectrum have shorter wavelengths and more energy.
The electromagnetic rays just beyond the red end of the visible light spectrum are called infrared - they are warming, but invisible. (The "warming lamps" you see keeping food warm at your local eatery emit infrared radiation. But these lamps also emit visible red light so people know they are on! The same is true for other types of heat lamps.)
On the other end of the visible light spectrum, blue light rays with the shortest wavelengths (and highest energy) are sometimes called blue-violet or violet light. This is why the invisible electromagnetic rays just beyond the visible light spectrum are called ultraviolet (UV) radiation.
 

BORIS OPTICAL  is one of the most Potential Finished and Semi-Finished Optical Lenses factory located in Danyang City, China. It was establish in 2012 with covering  20000 spm  and  150 employees . The annual production and sales of lenses are  30 million pieces,  and the annual sales have exceeded  100 million  for five consecutive years.
Our Key & Advantage Products:
Single Vision Lens:1.49;1.56;1.59;1.60;1.67;1.74
Bifocal Lens: 1.49; 1.56
Progressive Lens: CR-39; 1.56; 1.60
Functional Lens: Blue Cut, Photochromic; Photochromic +UV420 Blue cut; Sunglasses; Polarized; Polycarbonate
RX Service: Free Form; Special Coating; Special Power Range