Photonics Lab Instructional Videos

Align a Laser Beam Level to the Optical Table

Two methods for aligning a laser beam so that it propagates parallel to the surface of the optical table are demonstrated.

The first technique adjusts the pointing angle of a laser, whose tip and tilt can be adjusted. Using a ruler, the laser beam is leveled and directed along a row of tapped holes in the table.

Starting with this aligned beam, the technique for changing both the direction and the height of a beam from a fixed laser source is demonstrated. Two mirrors, which are set at different heights, direct the beam along another row of tapped holes in the table. The beam is then leveled at the height of the second mirror using two irises.

Components include a PL202 laser module, KM100 kinematic mounts, AD11NT adapter,  BHM1 ruler,  PF10-03-P01 mirrors, and IDA25 irises.

Date of Last Edit: Sept. 8, 2020

Tuning a Free Space Optical Isolator for Operation at the Laser Wavelength

Tuning a Faraday isolator ensures optimal transmission of optical power from the source, as well as effective suppression of reflections traveling back towards the source. Tuning is demonstrated using an IO-3-532-LP polarization-dependent free-space isolator with a 510 nm to 550 nm operating range, an R2T post collar, a PL201 linearly polarized and collimated 520 nm laser, a S120C silicon power sensor, and a PM400 power meter.

These optical isolators output linearly polarized light and provide best performance when the input beam is linearly polarized.

Always follow your institution's laser safety guidelines. Unlike the low-power source used in this demonstration, other laser sources may be damaged by back reflections. Many stray reflections, which can endanger colleagues and the laser, can be avoided by blocking the laser beam when it is not needed. 

Date of Last Edit: Sept. 10, 2020