A brief introduction: optical spherical lens processing basic knowledge

The processing of optical parts is divided into hot processing, cold processing and special processing, and hot processing is mostly used in the preparation of optical parts.

Cold working is done by sawing, rough grinding, fine grinding, polishing and centering edging with bulk abrasive or fixed abrasive.

Special processing only changes the properties of the polished surface, without changing the shape and size of the optical part, which includes coating, calibration, photography and gluing.

The main tasks of each process of cold processing are:

Milling process: remove the uneven bubbles and impurities on the surface of the lens, play a molding role;

Fine grinding process: the parts are processed to the specified size and requirements, the damage layer of the lens milling out is eliminated, and the R-value is fixed to prepare for polishing;

Polishing process: is to make the surface of the part bright and achieve the required optical accuracy;

Centering process: The outer circle of the lens is processed relative to the optical axis, grinding the outer diameter of the lens to the specified diameter;

Coating process: coating anti-reflection, reflection and other films on the surface of the lens;

Gluing process: is to glue different optical parts together, so that the optical axis overlap or turn in a certain direction;

Blackening process: apply a layer of black ink on the hairy surface of the lens to achieve the purpose of extinction;

How to maintain the accuracy of the surface curvature radius of the coarse grinding dish?

Rough grinding is carried out by means of contact between the grinding dish and the lens surface. Although the radius of curvature of the surface of the grinding dish is well modified at the beginning of use, the grinding dish is also constantly worn with the grinding of the lens, and gradually the processing accuracy of the lens is not necessarily guaranteed.

To keep the curvature radius of the coarse grinding dish unchanged or less changed, it should be taken:

Reasonable selection of working tools

Any fixture located on the top is always smaller than the size of the lower fixture, because the upper fixture needs to swing.

If the size of the upper fixture is the same as the size of the lower fixture, the edge grinding opportunities of the upper fixture are too few, and the upper fixture has a tendency to warp the edge.

If the size of the upper fixture is too small than the size of the lower fixture, exceeding the specified data, the edge of the upper fixture is not exposed during the swing process, the edge of the upper fixture will be worn too much, and the upper fixture has a tendency to collapse.