Investigation on the Differential Quadrature Fabry–Pérot Interferometer with Variable Measurement Mirrors

Abstract

Due to the common path structure being insensitive to the environmental disturbances, relevant Fabry–Pérot interferometers have been presented for displacement measurement. However, the discontinuous signal distribution exists in the conventional Fabry–Pérot interferometer. Although a polarized Fabry–Pérot interferometer with low finesse was subsequently proposed, the signal processing is complicated, and the nonlinearity error of sub-micrometer order occurs in this signal. Therefore, a differential quadrature Fabry–Pérot interferometer has been proposed for the first time. In this measurement system, the nonlinearity error can be improved effectively, and the DC offset during the measurement procedure can be eliminated. Furthermore, the proposed system also features rapid and convenient replacing the measurement mirrors to meet the inspection requirement in various measuring ranges. In the comparison result between the commercial and self-developed Fabry–Pérot interferometer, it reveals that the maximum standard deviation is less than 0.120 μm in the whole measuring range of 600 mm. According to these results, the developed differential Fabry–Pérot interferometer is feasible for precise displacement measurement.

A Novel Analog Interpolation Method for Heterodyne Laser Interferometer

“…Therefore, the initial resolution of the grating-based encoder is about 4 to 40 μm ( Table S3, Supplementary Material ). On the other hand, the initial resolution of the interferometry-based encoder is based on the laser wavelength and the optical structure [ 2 , 12 ], and its initial resolution is about 0.16 μm or 0.32 μm, depending on its interferometer factor [ 13 ]. There have been several times where deviations have existed between the grating-based encoder and the interferometry-based encoder.…”

“…Advanced encoder systems are usually based on laser interferometers, due to their high initial resolution and the connection to the definition of the meter [ 1 ]. The common initial resolutions of the laser interferometers are about 0.32 μm or 0.16 μm, depending on the optical structure [ 2 ] ( Table S1, Supplementary Material ). The initial resolution of the laser interferometer is several times higher than that of a grating-based encoder system [ 3 ], and laser interferometers also have the feature of error reduction [ 4 , 5 , 6 ].…”

Special Issue on Manufacturing Metrology

“…Using a combination of laser triangulation sensors and a contact probe, not only the distance of two parallel surfaces but also the difference between surface shape contours can be measured to micrometer-scale accuracy [2]. With a multi-path laser interferometer, a new computational model for step gauge calibration was proposed based on synthesis technology [3], and a differential quadrature Fabry-Pérot interferometer was proposed separately [4]. In this measurement system, the nonlinearity error can be improved effectively and the DC offset during the measurement procedure can be eliminated.…”

Fiber Optic Sensors for Vital Signs Monitoring. A Review of Its Practicality in the Health Field

“…Reproduced from Refs. [ 19 , 25 , 28 , 32 , 39 , 40 , 56 , 85 , 94 , 95 , 96 , 106 , 107 ] Sensors Journal, Materials Journal, Applied Sciences Journal, Fibers Journal and Journal of Functional Biomaterials of the MDPI. Reproduced from Refs.…”