Industrial Technology Research Institute

National Taipei University of Technology

Huang-Chi Huang

Kai-Yu Cheng

Hung-Ming Tai

Ching-Ming Yeh

Jung-Tsung Chou

Chiung-Huei Huang

Liang-Chia Chen

Jin-Liang Chen

Huang-Wen Lai

Yong-Tong Zou

Chun-Tai Lien

A exemplary method for determining vibration displacement in interferometric scanning, in which two optical signals having a phase difference with each other of a high-coherence interferogram corresponding to a tested surface is detected for determining a shifting displacement between the reference plane of interferometric apparatus and the tested surface. In one embodiment, a series of the shifting displacements with respect to a time interval are measured for determining the vibrating frequency of the tested surface by spectrum analysis. Meanwhile, an exemplary interferometric apparatus is also disclosed for calculating the relative position between the tested surface and the reference plane of interferometric apparatus whereby the interferometric apparatus is capable of compensating influences of vibration caused by the environment or the tested surface itself so as to obtain the surface profile and vibration frequency of the tested surface.

Method for determining vibration displacement and vibrating frequency and apparatus using the same

A fiber optic interferometric position sensor and measurement method thereof suitable for determining the moving direction of a measurement object in an environment of high electric or magnetic field strengths are disclosed. The fiber optic interferometric position sensor comprises at least one light source, a plurality of fiber optic couplers, a plurality of sensing fibers and a plurality of photodetectors. The fiber optic couplers are connected to the at least one light source, the photodetectors, and the sensing fibers, respectively. The measurement method comprises: providing a fiber optic interferometric position sensor and a measurement object, obtaining two initial signals having a 90-degree phase difference therebetween, obtaining two measured signals, correcting the measured signals by a bias correction method, obtaining the phase value from the two measured signals by an electronic interpolation technique, and obtaining the position of the measurement object after computation by using the phase value.

Fiber optic interferometric position sensor and measurement method thereof

Growing community of inventors

Hsinchu, Taiwan

Huang-Chi Huang