Since the 1980s, many new types of aspheric super-precision machining technologies have appeared, including:
- Computer numerical control single-point diamond turning technology,
- Computer numerical control grinding technology,
- Computer numerical control ion beam forming technology,
- Computer numerical control ultra-precision polishing technology.
- Copying techniques, etc.,
These processing methods basically solve the problems in the processing of various aspherical mirrors.
The first 4 methods use numerical control technology, high processing precision and high efficiency, are suitable for mass production.
When machining of aspherical parts, factors such as the material, shape, precision and parts size should be considered.
For soft materials such as copper and aluminum, can use single point diamond cutting (SPDT).
For glass or plastics, currently use ultra-precision processing of the mold, and then use the mold to produce aspherical parts,
For other high-hardness brittle materials, mainly through ultra-precision grinding, polishing and other methods.
Additionally, there are also special processing techniques for aspherical parts such as ion beam polishing.
The high-precision aspherical part can be manufactured by the polishing (grinding) method of controlling the thickness, but the processing efficiency of this method is low compared with the general optical part processing method, for this problem one solution is Copying technology, which called plastic injection molding and glass molding technology.
Plastic lens injection molding is a processing method in which molten resin is injected into a mold and a pressure is applied to cool and solidify.
This method can be inexpensively and mass-produced, but there are some problems of the plastic itself, the refractive index maybe change as temperature change and moisture absorption.
For more information about Aspherical lens processing, welcome to contact LPO!
