dc.description.abstract | High-precision length measurement and positioning are the essential key points for the development of precision engineering. Because laser interferometers possess the measuring characteristics of large measuring range and high resolution simultaneously, they are widely employed in the calibration of the linear axis in the machine tool and the micro-electromechanical device′s positioning.
However, the measurement stability of conventional interferometers is susceptible to environmental disturbances. To achieve high-precision measurement performance, it is necessary to strengthen the control of the surrounding environment′s conditions. For this reason, the development of an interferometer with high stability and applicability is a critical issue. According to the previous study, the interferometer with the common path structure is insensitive to environmental disturbances. Therefore, this study based on this optical structure implements the optomechanical design and the construction of the signal processing to develop two types of Fabry-Pérot interferometric displacement measurement modules, which can meet the inspection requirements with high precision and can enhance the measurement accuracy.
Additionally, according to the technological development and the review of industrial applications, the inspection of multi-degree-of-freedom geometric errors is the expectable trend of industrial development. Therefore, this study orientates itself in the development of multifunctional inspection and modular integration, and the corresponding photoelectric inspection modules are constructed to measure the straightness, pitch, and yaw angle. Each module can be utilized individually or integrated collectively according to the user’s demands to achieve the inspection purpose of axial multi-degree-of-freedom geometric errors. Furthermore, to improve the measurement accuracy and the alignment convenience, the automatic optical alignment module proposed in this study can also be integrated into other measurement modules to enhance the inspection efficiency.
With this development of optical alignment and various inspection modules, the measurement performances can be realized in the following descriptions. The correlated measurement repeatability of the polarized Fabry-Pérot interferometer and the polarized differential Fabry-Pérot interferometer proposed in this study is less than 0.171 μm and 0.120 μm, respectively, during the large measuring range. The verification result of the straightness measurement module indicates that the repeatability is less than 0.279 μm. The verification result of the measurement module of the pitch and yaw angle indicates that the measurement repeatability is less than 0.24 arcsec. And by the evaluation of the experimental result for the optical alignment module, the cosine error can be reduced to less than 1 nm after the alignment procedure. The simultaneous measurement results of the five-degree-of-freedom laser interferometer system demonstrate that the repeatability of the linear displacement, straightness, and the tilt angle is less than 0.106 μm, 0.252 μm, and 0.22 arcsec, respectively.
The above testing results reveal that each module can be easily used and flexibly integrated through the streamlined optomechanical design. High-efficiency and high-precision inspection can be achieved without complicated optomechanical alignment. | en_US |