We present a compact heterodyne laser interferometer developed for high-sensitivity displacement sensing applications. This interferometer consists of customized prisms and wave plates assembled as a quasi-monolithic unit to realize a miniaturized system. The interferometer design adopts a common-mode rejection scheme to provide a high rejection ratio to common environmental noise. Experimental tests in vacuum show a displacement sensitivity level of
Multipass etalon cascade for high-resolution parallel spectroscopy
Spectral contrast, the ability to measure frequency components of vastly different intensity, is critical in optical spectroscopy. For high spectral contrast at high spectral resolution, scanning etalons are generally used, as they allow cascading multiple dispersive elements. However, scanning instruments are inherently limited in terms of acquisition speed. Here we report a single-shot cascaded spectrometer design, in which light is dispersed along a single dispersion direction at every stage and thus can be recirculated in the same etalon multiple times. Using this design principle, we demonstrate single-shot spectral measurements at sub-gigahertz resolution and unprecedented spectral contrast (
- PAR ID:
- 10212751
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- Volume:
- 46
- Issue:
- 4
- ISSN:
- 0146-9592; OPLEDP
- Format(s):
- Medium: X Size: Article No. 781
- Size(s):
- Article No. 781
- Sponsoring Org:
- National Science Foundation
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