Double-optical-fiber coupling ball microscale sensor based on polarization state detection

Abstract

The invention provides a double-optical-fiber coupling ball microscale sensor based on polarization state detection and belongs to the technology of manufacturing and measurement of precise instruments. The double-optical-fiber coupling ball microscale sensor comprises a laser, a polarizer, a semi-transparent semi-reflective prism, a quarter lambda wave plate, a probe, polarization state detection devices and a computer, wherein the probe is composed of an incidence optical fiber, an emergent optical fiber and a coupling ball, the laser, the polarizer, the semi-transparent semi-reflective prism, the quarter lambda wave plate and the probe are arranged in sequence. The optical axis of emergent light of the laser and the optical axis of incident light of the incident optical fiber coincide. The polarization state detection device A is located on the optical axis of the path of reflected light formed after the emergent light of the emergent optical fiber is reflected by the semi-transparent semi-reflective prism. The polarization state detection device B is located on the optical axis of the path of reflected light formed after an emergent light beam of the laser passes through the polarizer and then is reflected by the semi-transparent semi-reflective prism for the first time. When the difference value between the polarization state, detected by the polarization state detection device A, of a light beam and the polarization state, detected by the polarization state detection device B, of the light beam is changed, the probe is in contact with a detected hole for detection. The double-optical-fiber coupling ball microscale sensor is high precision and high in speed and has the three-dimensional measurement capacity.

Description

technical field [0001] The invention belongs to the manufacturing and measuring technology of precision instruments, and mainly relates to a dual-fiber coupling ball microscale sensor based on polarization state detection. Background technique [0002] With the continuous development of the aerospace industry, automobile industry, electronics industry and cutting-edge industries, the demand for precision and tiny components has increased dramatically. Due to the limitation of the space scale and the shadowing effect of the tiny components to be measured and the influence of the measurement contact force, it is difficult to realize the precise measurement of the size of the tiny components, especially the measurement depth of the tiny inner cavity components is difficult to increase, which has become a constraint to the development of the industry. "bottleneck". In order to achieve smaller internal dimension measurement and increase the measurement depth, the most widely use...

AI Technical Summary

Problems solved by technology

The low-light bead scattering imaging method of PTB in Germany is affected by the shadowing effect, which makes it difficult to improve the measurement depth and reduce the detection accuracy of the system

Although the probe structure based on dual-fiber coupling overcomes the shadowing effect to a certain extent, it has not yet solved the problem that the light energy transmitted in the reverse direction is very limited, and it is difficult to further improve the measurement depth.

[0011] 2. It is difficult to further improve the displacement resolution of the detection system

The primary magnification of the existing detection system is low, resulting in a low overall magnification, and it is difficult to further improve its displacement resolution

The optical path magnification of the optical measuring rod used in the detection method adopted by the National Institute of Standards and Technology is only 35 times, and the low primary magnification makes it difficult to further improve the displacement resolution.

[0012] 3. The real-time performance of the detection system is poor, and it is difficult to achieve precise online measurement

The detection method adopted by the National Institute of Standards and Technology must use two-way area array CCDs to receive signal images, and a more complex image algorithm must be used to achieve high-resolution monitoring of the displacement of the optical fiber measuring rod, which leads to a large amount of data that the measurement system needs to process. increase and reduce the real-time performance of the detection system, it is difficult to realize the synchronization of the small inner cavity size and the synchronization of the aiming signal and the start and stop measurement in the process of two-dimensional coordinate measurement

[0013] 4. There is coupling of two-dimensional radial touch displacement and insufficient detection ability of three-dimensional displacement direction

The probe of the micropore size measurement method based on FBG Bending has the same performance in all directions, and there is coupling in the radial two-dimensional touch displacement sensing, and it cannot be separated, resulting in a large error in the two-dimensional measurement, and the radial two-dimensional measurement cannot be realized. Accurate measurement of dimensional contact displacement

The probe structure based on dual-fiber coupling proposed by Harbin Institute of Technology does not have three-dimensional detection capabilities, and can only achieve micro-scale two-dimensional measurement, which cannot meet the needs of current micro-scale three-dimensional measurement

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