Spheres : The curved surface forms a part of the spherical lens and the dioptric power on all axis positions is the same. After passing the lens, the light beam focuses in one point (or a virtual focus). Spherical lens includes concave lens （ - ） and conv...
Presbyopia is a physiological phenomenon that generally begins to appear between the ages of 40 and 45, as the eyes age, the elasticity of the crystalline lens weakens, meaning that the camera lens cannot freely retract and retract, resulting in the objec...
Blue light is divided into two types: beneficial and harmful, the blue light with wavelengths between 415 and 455 nanometers is harmful blue light in short waves and requires special attention to protection...
There are 18 worldwide Glasses Exhibition in 2024, check the detail date here......
When purchasing lenses, many people may find that they do not understand why they choose to coating lenses that are resistant to blue light, and the differences between film layers are not very clear. So, let's popularize the most common blue film and gre...
block ultraviolet and electromagnetic radiation, but radiation resistant glasses cannot prevent blue light...
HMC lenses are high transmittance lenses that can effectively reduce glare and reflection. HMC is the abbreviation for "Hard Multi Coating", which means hard multi-layer coating....
About what is Myopia, how it comes, how to prevent and control myopia, what period should pay more attention during child grow up......
Aricale about what is astigmatism. Understanding the theory would be very helpful during the astigmastism examing, prevention, practising ....
Articale about why get cataracts, cataract surgery ask, how IOL sould be selected......
