Introduction to Aspheric Lenses
The aspheric lens has a fixed curvature from the center to the edge, while the curvature of the aspheric lens continuously changes from the center to the edge. In various lenses, in order to ensure optimal performance, aberrations need to be corrected. If only a spherical lens is used for correction, many lens combinations are required to correspond to the technical requirements of the lens. The radius of curvature of the aspheric lens changes with the central axis, so the number of optical elements used can be reduced, thereby reducing the design cost.
With unique optical characteristics and better imaging effects, aspheric optical parts have become indispensable optical devices in the military, civil, and aerospace fields.
Aspheric processing
The aspheric surface processing technology is mainly divided into four parts: blank production, grinding shaping, polishing processing, and inspection of each process.
First, process the spherical blank according to the design requirements. Choose suitable fixtures according to the size of the blanks, and then the basic processes such as rough grinding, fine grinding, and polishing of aspheric surface processing. After the aspheric surface is milled, the profiler should be used to detect the surface shape, and the surface shape deviation should be corrected according to the test results. After repeated inspections and corrections, the polishing process, which is an important part of ensuring the accuracy of the surface shape, is reached. The purpose is to achieve the required optical quality standards for the surface shape finishing on the basis of fine grinding.
At present, because optical elements are widely used in various fields, the traditional processing methods of aspheric lenses the past can no longer meet the needs of today’s market in terms of processing efficiency and processing costs. The rapid development of ultra-accurate processing technology, the emergence of high-accuracy machine tools, and the combination of computer technology have made a breakthrough in the processing technology of aspheric optical components.
This technology uses ultra-accurate milling machine tools to grind and shape the optical element blanks, and then use computer simulation polishing to determine reasonable polishing parameters, select the polishing parameters to calculate the motion trajectory and residence equation, and reduce the surface accuracy while ensuring The surface roughness of the components meets the requirements of the processing quality of optical components