Interferometric confocal measurement system and measurement method

Abstract

The present invention provides an interference confocal measurement system and measurement method. The measurement system includes a first measurement unit and a second measurement unit. The first measurement unit includes a wide-spectrum light source assembly emitting a specific wavelength range, a first beam splitter, Dispersion objective lens, signal receiving assembly; the second measurement unit includes a single-wavelength laser light source, a beam expander, a second beam splitter, a phase shifter, a reflector, a photodetector, a third beam splitter, and a Aperture on the central optical axis. The invention measures step by step, the first measurement unit realizes rough measurement and determines the interference order; the second measurement unit realizes fine measurement, and while ensuring single-wavelength measurement accuracy, the working range of the interference confocal measurement system is expanded.

Description

Technical field [0001] The present invention belongs to the field of optical detection technology, specifically relates to an interferometric confocal measurement system and method. Background [0002] With the development of modern optical precision measurement technology, higher requirements are put forward for the measurement of surface contour and surface shape error of components. In the process of the development of optical instruments and equipment, optical components have undergone a process from spherical, aspheric to freeform, in which freeform breaks the limitations of aspheric rotational symmetry and further improves the performance of optical systems. [0003] The detection of freeform optics is generally divided into two types: contact and non-contact detection. There are many advantages of contact measurement represented by the three-coordinate measurement method, but it also has problems such as direct contact with the surface of the workpiece, easy to destroy the...

AI Technical Summary

Problems solved by technology

However, due to the uneven distribution of the intensity of each wavelength of the outgoing light of the existing light source, the measurement accuracy will be significantly reduced.

And after the object to be tested reflects the beam, since the reflected beam enters the spectrometer along the optical path of the dispersive objective lens, the purity of the spectrum received by the spectrometer is not high, resulting in deviations in the measurement results and reducing the measurement accuracy

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