Basic Knowledge Of Lens

Do you know the basics of glasses?Do you know how lenses are made?Do you know how to identify lenses?Do you know the technical term for lens?Today let's have a brief introduction.

Lens making process

Batching - mould cleaning - mould closing - pouring - primary curing - mould opening - grinding - cleaning - secondary curing - hardening - coating - finished product inspection - finishing packaging - storage

1. According to the refractive index points are: 1.49 (CR39) / 1.56/1.523 / / 1.67/1.74/1.591/1.61

The hinger the refractive index ,the thinner the lens ,but the lens appropriate it is for the eyeball

*1.49 Commonly known as CR39 color-free resin material is easy to turn yellow after a long time, not for domestic sales (Mexico market)

*1.56 discoloration resin general customers to discoloration films are 1.56 (all major markets)

*1.591 PC sheet hardness thick, not broken and difficult to cut, after falling ball test Myopia of 

*1.61 discoloration resin buys the person that 600 inside prevent blu-ray to be in the majority more

*1.67 color change resin myopia within 800 people buy more

*1.523 Heavy and scratch resistant glass pieces generally semi-finished products are mostly bought (Peru market)

*1.74 The price of special materials is too expensive for many people to buy. At present, there is basically no one to do it in China, so it needs to be imported

2.Lens processing to distinguish UC/HC/HMC

*UC white sheet/substrate, without any processing. 1.49 Its hardness is good, so there is no need to pay for the hard sheet, generally directly buy UC or HMC

*HC hardening, such as 1.56 resin sheet is easy to scratch, so it must be hardened, 1.56 white sheet is not sold Under normal circumstances, we plating blue/green film with 

*HMC and hard film. If the customer has other film color requirements, we can also do it. The price needs to be negotiated

3.What varieties are available at each refractive index

*1. Single vision SV

*The Flat top is very similar to the Invisible Round top

*3. Progressive short channel 12/14mm, long channel 17MM

*Semi Finish （B2/B4/B6/B8/B10）

4.Key words diopter representation

*S(sphere) : spherical light, myopia is indicated by "-", and the middle is thin and the sides are thick

Presbyopia is denoted by "+" (plus);Thick in the middle and thin on the sides

*C(cylinder) : indicates astigmatism, usually marked with "-", but + is more used in Europe and the US.The astigmatism ranges from -0.25 to -2.00, the astigmatism ranges from -2.25 to -4.00, and the astigmatism ranges from -2.25 to -6.00.There are highlights on the opposite sides of the lens.Plus or minus 2. Oo / 2.00