Uploaded June 2026 | Updated September 2026, 3 hours ago

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This video demonstrates a step-by-step alignment guide outlined in the Thorlabs Quantum Optics Educational Kit User Guide to align and perform the Malus' Law experiment.

In this video, the polarizer was calibrated to the output of the BBO crystal and not to the table plane. To see a video that aligns polarizers to the table plane for S- and P-polarization, please watch:
youtube.com/watch?v=W9pALZ5Z8ms

For more information on the Quantum Optics Educational Kit, visit thorlabs.com/newgrouppage9.cfm?objectgroup_id=15827&ytid=BNXppZGtM9E.

This video was created in collaboration with Brandon Mitchell from West Chester University and performed by Nick Gray from West Chester University.

0:00 Introduction
0:30 Polarizer Calibration
1:00 Set Polarizer Dial
1:27 Position Polarizer
1:48 Malus' Law Measurement
3:35 Remove Last Point
5:16 Result of Malus' Law Measurement
5:37 g2(0) Spikes