Monitoring your laser Position and Beam Size over time in StarLab with a BeamTrack sensor

June 23, 2021

Jonathan Feust

StarLab is Ophir’s easy-to-use, yet powerful, laser measurement software that turns a PC into a multi-channel laser power / energy display station.

BeamTrack sensors are a unique series of Ophir thermopile sensors that can measure beam position and beam size while measuring power at the same time, all combined in one sensor.

BeamTrack sensors provide continuous feedback of the laser power, beam size and the X Y coordinates of the laser’s relative position on the sensor’s surface.

Measuring laser position is important for alignment, and monitoring of laser position drift.

When a BeamTrack sensor is in its Track measurement mode, the Power and Beam Size measurements can be used together to calculate power density.
Beam Position measurements can be used to set up the optical alignment of a laser
Beam Position measurements can also be used for tracking the laser pointing stability and drift over time – beam wander. This is where displaying and logging the laser position coordinates over time comes into play.

In StarLab a special graphic display tracks the pointing stability of the laser beam over time in a color-coded matrix of ‘cells’ representing the number of counts of the beam center at particular coordinates on the BeamTrack sensor. As the stability measurement proceeds, the cells change color. Additionally, numerical analysis data of the laser position and drift over time is displayed on the side of the graph, as shown below:

2. In addition to being able to track the laser position over time graphically via the StarLab stability display, you can also record the numerical laser position coordinates over time, together with the laser power and beam size, by logging the measurements into a text file.

The log file can then be analyzed by utilities such as Excel, as shown below: