Micromachined force balance for optical power measurement by radiation pressure sensing

Published

August 6, 2018

Author(s)

Ivan Ryger, Alexandra B. Artusio-Glimpse, Paul A. Williams, Nathan A. Tomlin, Michelle S. Stephens, Matthew T. Spidell, Kyle A. Rogers, John H. Lehman

Abstract

We introduce a micromachined force scale for laser power measurement by means of radiation pressure sensing. With this technique, the measured laser light is not absorbed and can be utilized while being measured. We employ silicon micromachining technology to construct a miniature force scale, opening the potential to its use for fast in-line laser process monitoring. Here we describe the mechanical sensing principle and conversion to an electrical signal. We further outline an electrostatic force substitution process for nulling of the radiation pressure force on the sensor mirror. Finally, we look at the performance of a proof- of-concept device in open-loop operation (without the nulling electrostatic force) subjected to a modulated laser at 250 W and find its response time is less than 20 ms with noise floor dominated by electronics at 2.5 W/√Hz.

Citation

IEEE Sensors Journal

Volume

18

Issue

19

Pub Type

Journals

Download Paper

https://doi.org/10.1109/JSEN.2018.2863607

Keywords

Capacitive sensor, Differential arrangement, Opto-mechanical characterization, Photon momentum, Power measurement spring constant measurement

Citation

Ryger, I. , Artusio-Glimpse, A. , Williams, P. , Tomlin, N. , Stephens, M. , Spidell, M. , Rogers, K. and Lehman, J. (2018), Micromachined force balance for optical power measurement by radiation pressure sensing, IEEE Sensors Journal, [online], https://doi.org/10.1109/JSEN.2018.2863607 (Accessed October 8, 2025)