1, the refractive index: light from a vacuum to spread to other medium, incident Angle and the Angle of refraction of sine ratio called the refractive index of the medium.
The higher the refractive index, the thinner the lens.
For example, a single focus aspherical lens high lens refractive index is 1.
665, it is said that if you are a 500 degree, make use the lens glasses, than the refractive index of 1.
449 more thin lens, more beautiful sex!
So, that is, the deeper the degree of people, need the higher the refractive index.
The higher the refractive index, the more expensive.
Some consumers figure to taobao cheaper glasses, lenses and assembling the lens refractive index of some taken root.
A price, a quality: glasses entity store had more professional ones.
2, abbe number: also known as the dispersion coefficient, the abbe number is big, see things more clearly.
The phenomenon of 'rainbow' value, the smaller the lens will be more serious, adverse to the wearer.
Lens abbe number generally between 30 -
Between 60, the higher the refractive index of the lens the abbe number is lower, for resin lens refractive index on the abbe number is bigger, the influence of refractive index of 1.
50 CR - 39 lenses, the abbe number 58.
The abbe number 56 refractive index, as a general rule, be 36 -
38 and refractive index of 1.
The six slim resin lenses, most domestic companies with acrylic materials, its highest abbe number only 32.
Good abbe coefficient reached 48 Gao Qingfang blu-ray series!
Japan's mitsui, operation m optics, with its advanced materials research and development ability for backing, on the lens as VCD to upgrade to DVD epoch-making revolution, design the refractive index of 1.
MR - 6
8 patents material, make its abbe number may reach 42, ensures the wearer's visual resolution, at the same time the anti-aging properties of the material, toughness and heat resistance are all similar products can not meet.
3, resistance to ultraviolet radiation (
Ultraviolet (UV) based on wavelength can be divided into: near ultraviolet UV -
A wavelength of 320 nm to 400 nm,
UV, UV -
B: the wavelength of 280 nm to 320 nm UV and UV -
C: 200 nm to 280 nm uv light.
UV damage to the eyes: UV -
A easy to cause corneal burns, vitreous body turbidity, cataract;
B: easy to cause keratitis, corneal dry, red conjunctival congestion;
C: easy to cause eye fatigue.
4, resistance to radiation (
, anti-static, radiation is a kind of electromagnetic wave, the main radiation resistant, antistatic function of the lens is in the electromagnetic waveguide lens surface coated with a layer of conductive material into the surrounding.
A radiation protection lens on the present electronic product such as the radiation wave has good blocking effect, and anti-static lens is helpful to prevent the lens surface adsorption dust, let the lens more clean.
Against blue: 5, blue light is now smart devices against harmful blue light reflected design and build membrane layer, the blue lenses series which has the function of anti blu-ray lens, more to protect his eyes from the blue.
Spend for charming eye, we help you choose glasses!