Optical-fiber frequency domain interferometer with nanometer resolution and centimeter measuring range

Abstract

A new optical-fiber frequency domain interferometer (OFDI) device for accurate measurement of the absolute distance between two stationary objects, with centimeter measuring range and nanometer resolution, has been developed. Its working principle and on-line data processing method were elaborated. The new OFDI instrument was constructed all with currently available commercial communication products. It adopted the wide-spectrum amplified spontaneous emission light as the light source and optical-fiber tip as the test probe. Since this device consists of only fibers or fiber coupled components, it is very compact, convenient to operate, and easy to carry. By measuring the single-step length of a translation stage and the thickness of standard gauge blocks, its ability in implementing nanometer resolution and centimeter measuring range on-line measurements was validated.

Rapid measurement of large step heights using a microscopic white-light spectral interferometer

“…The measurement range of the absolute distance, that is, the OPD, by the WLSI can be described by the following equation [12][13][14]:…”

All-Fiber Pulse-Train Optical Frequency-Domain Interferometer for Dynamic Absolute Distance Measurements of Vibration

“…According to the spectral coherence theory, an optical frequency-domain interferometer (OFDI) can realize the absolute distance or relative motion measurement in an ultra-fast dynamic process, such as shockwave propagation induced by ultra-intense short-pulse laser pump-probe technology [19]. In recent years, all-fiber OFDI has been developed [20], which is more compact, flexible, and robust than distance measurement technology based on bulky optical elements such as LCI. The structures of co-axial light paths have long-distance ranges of more than 100 mm, which transcend those of TOF and LCI, and high accuracy levels of above 5 µm.…”

Note: A novel method to measure the deformation of diamond anvils under high pressure

“…In this article, a novel method based on optical-fiber frequency domain interferometer (OFDI) 13 is presented, the dea) Author to whom correspondence should be addressed. Electronic mail:…”

“…The details of this data processing are given in Ref. 13. From the Raman scattering, 14, 15 synchrotron x-ray imaging and stress measurements 6 and FEM calculation, 7 we know that the stress is concentrated in a limited area around the culet (the drastic change occurs within the first 200 μm measured from the diamond-sample interface 15 ).…”