Automated translating beam profiler for in-situ laser beam spot-size and focal position measurements

TL;DR

This paper introduces a low-cost, automated laser beam profiling device using a Raspberry Pi and CMOS camera for in-situ measurements of beam spot size and focal position, with software support and versatile wavelength sensitivity.

Contribution

The paper presents a novel, affordable, and automated laser profiling system that integrates hardware and software for in-situ measurements of laser beam parameters.

Findings

Effective measurement of laser focal position demonstrated

Device sensitivity over 300-1100 nm wavelength range

Automated profiling improves measurement efficiency

Abstract

We present a low-cost, high-resolution solution for automated laser-beam profiling with axial translation. The device is based on a Raspberry Pi, Pi Noir CMOS camera, stepper motor and commercial translation stage. We also provide software to run the device. The CMOS sensor is sensitive over a large wavelength range between 300-1100 nm, and can be translated over 25 mm along the beam axis. The sensor head can be reversed without changing its axial position, allowing for a quantitative estimate of beam overlap with counter-propagating laser beams. Although not limited to this application, the intended use for this device is the automated measurement of the focal position and spot-size of a Gaussian laser beam. We present example data of one such measurement to illustrate device performance.