In-site measurement system of aspheric die and measurement method and measurement examination method of system

Abstract

The invention discloses an in-site measurement system of an aspheric die. The system comprises a contact probe, an air-floatation bearing, an optical interference system, an image collecting and processing system and software processing system; the optical interference system comprises a light source, a laser beam expanding system, an cat eye reflector, two reflectors, a polarized spectroscope, a 1 / 2 lambda wave plate, three 1 / 4 lambda wave plates, a beam splitting grating or a holographic beam splitting unit, a space filter and a Polaroid group; the image collecting and processing system comprises a CCD camera, an image collection card and a computer; and the software processing system comprises a phase calculation module, a surface coordinate conversion module, a curved surface fitting module and an error analysis module. The system and methods thereof have the advantages that the displacement measuring precision can reach the nanometer magnitude, real-time in-site measurement can be realized, interference of vibration noises can be avoided in the measurement process, and the measuring accuracy and stability are high.

Description

technical field [0001] The invention relates to a three-dimensional measurement device based on optical interference technology, in particular to an in-situ measurement system of an aspheric mold, a measurement method and a measurement inspection method thereof. Background technique [0002] At present, the lenses of various camera devices have been developed towards thinner and shorter, and tiny aspheric lenses (with a diameter of several millimeters to tens of microns) have become the main force of this development trend. According to the statistics of the Taiwan Optoelectronics Technology Industry Association (PIDA), based on the calculation that a digital camera needs to be equipped with 1 to 3 aspheric molded glass lenses, in 2007, there were about 230 million aspheric molded glass lenses on the digital camera. Demand, the world's aspherical molded glass lens production value accounts for about 19% of the world's optical components production, aspheric molded glass lens...

AI Technical Summary

Problems solved by technology

Shear interferometry does not require a standard reference wave surface, and can flexibly measure aspheric surfaces of various shapes, but it has the following disadvantages when used in in-situ measurement: 1) Due to the harsh requirements of interference on the environment, the measurement process should avoid environmental vibrations and noise interference, which is difficult to achieve on machine tools; 2) The measurement accuracy needs to be improved. For high-precision micro-aspheric molds, the in-situ measurement accuracy of the existing shear interferometer cannot reach the nanometer level; 3) the shear The processing of the tangential interferogram is relatively complicated, which restricts the real-time performance of the on-site measurement to a certain extent

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