Angle changeable double reflection mirror dynamic liquid film thickness measuring instrument

Abstract

The present invention relates to an equipment for measuring thickness of polishing liquid film. Its technical problem required to solve lies in that the change of liquid film thickness can be converted into the change of turning angle of lower reflector relative to upper reflector. The technical scheme of solving said problem lies in that in angle-changeable double-reflector it adopts a structure in which a light sldie carriage is used to upwards support the lower reflector whose top rod support is equipped with smooth rotating shaft and make the lower reflector turn round rotating shaft, and utilizes the angle-changeable double-reflector mounted opposite to reflecting surface to make multiple reflection and emit laser beam, and said laser beam can be received by frosted glass. Said invention contains polishing system and measuring system, and implement reel-time dynamic measurement of liquid film thickness, can promptly regulate liquid film thickness, improve polishing conditon, raise working efficiency and ensure polishing quality.

Description

technical field [0001] The invention belongs to a measuring device for polishing liquid film thickness in the technical field of optical cold processing. Background technique [0002] In optical cold processing, it is often encountered that some lenses need to be processed with ultra-smooth surfaces. For example, in short-wavelength optics, the extreme violet lithography system used in the manufacture of VLSI requires the imaging quality of the optical system to be particularly clear. This requires the surface roughness of the optical lens to reach an ultra-smooth level of less than 1nm (RMS). [0003] Generally speaking, for optical cold processing of ultra-smooth surfaces, the usual grinding method of direct contact between the surface of the workpiece and the grinding disc cannot be used, but the grinding solution is used to fill the gap between the surface of the workpiece and the grinding disc. The relative movement of the workpiece forms the solution flow in the gap s...

AI Technical Summary

Problems solved by technology

This method only knows that the thickness of the liquid film has been adjusted. In fact, there is no concept of quantity for the thickness of the liquid film. Every time a workpiece is polished, the counterweight test must be adjusted, which brings trouble to the work and affects work efficiency and polishing. In order to overcome the above shortcomings, a device that can dynamically measure the thickness of liquid film in real time is specially designed.

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