Optical lens quality inspection system and method based on double-comb interferometry

Abstract

The invention belongs to the technical field of optical precision measurement, and discloses an optical lens quality detection system and method based on a double-comb interferometry method. The system includes a light source system, an interferometry system, and a signal processing system. The light source system includes a first optical frequency comb and a second optical frequency comb, which are used to generate two laser beams whose repetition frequency meets the heterodyne beat frequency condition; in the interferometric system, the output signal of the first optical frequency comb is divided into a measurement beam and a Two beams of reference beam, wherein, after the measurement beam is incident on the optical lens to be tested, it overlaps with the reference beam; the overlapped measurement beam and reference beam overlap with the output beam of the second optical frequency comb again and then are divided into two beams, which are divided into two beams respectively Two detection windows of the detector detect; the signal processing system is used to calculate the thickness and refractive index of the optical lens to be tested according to the detection signal of the detector. The invention can simultaneously measure the thickness and the refractive index of the glass lens, and realize the two-dimensional characterization of the glass lens.

Description

technical field [0001] The invention relates to the field of optical lens quality detection, in particular to an optical lens quality detection system and method based on a double-comb interferometry method. Background technique [0002] Since the announcement of the Nobel Prize in Physics in 2005, the performance of optical frequency combs has been continuously improved to meet different scientific challenges. Its application has brought revolutionary progress to many basic science and engineering applications, and has achieved Remarkable achievements, widely used in precision spectroscopy, sensing, distance measurement, tomography, telecommunications and other fields. [0003] With the rapid development of the field of precision measurement, experimental researchers have higher and higher requirements for the quality and precision of the optical system. In order to ensure the quality of the imaging of the optical system, it is more and more important to accurately detect t...

AI Technical Summary

Problems solved by technology

The mismatch between the refractive index and the design will directly affect the beam quality and imaging measurement. Similarly, if the thickness uniformity is too poor, it will also affect the normal experimental research

In order to achieve accurate measurement of the thickness and refractive index of optical glass lenses, scientists have proposed a variety of methods, including contact measurement methods and non-contact measurement methods. Among them, the contact measurement method has the advantage of convenience and low cost, but it is also easy to scratch. Injure the surface of the sample, causing damage to the sample

Non-contact measurement methods include goniometric method and interferometry. The goniometric method requires the measurement sample to be prepared into a special shape, so the small-diameter sample is generally used instead of the large-diameter glass refractive index, but the small-diameter sample cannot fully characterize the large-diameter glass. rate, real-time online detection cannot be realized, the measurement system is complex, and debugging is difficult

The measurement system based on the interferometry generally includes a movable scanning table, which will introduce mechanical errors, and the scanning range of the scanning table directly determines the maximum measurable sample thickness, which cannot realize the measurement of any glass sample

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