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Updated: Jun 3, 2026
11:15
A Guide to Structured Illumination TIRF Microscopy at High Speed with Multiple Colors
Published on: May 30, 2016
Note: Fast, small, accurate 90° rotator for a polarizer.
David P Shelton1, William M O'Donnell, James L Norton
1Department of Physics and Astronomy, University of Nevada, Las Vegas, Nevada 89154-4002, USA.
The Review of Scientific Instruments
|April 5, 2011
Summary
A modified stepper motor rapidly rotates a polarizer for precise light polarization measurements. This enables accurate intensity ratio analysis and signal drift compensation.
Area of Science:
- Optics and Photonics
- Mechanical Engineering
- Instrumentation
Background:
- Accurate measurement of light polarization states is crucial in various scientific fields.
- Existing methods for rapidly switching between orthogonal polarizations can be complex or lack precision.
Purpose of the Study:
- To develop a novel device for rapid and precise switching of light polarization states.
- To enable accurate measurement of intensity ratios for orthogonal polarized light components.
Main Methods:
- A permanent magnet stepper motor was modified to house a dichroic polarizer.
- The motor was controlled to achieve a 90° ± 0.04° rotation of the polarizer within 80 ms.
Main Results:
- The device successfully achieved rapid polarization switching (90° in 80 ms) with high accuracy (± 0.04°).
- The system demonstrated the ability to rapidly alternate between two accurately orthogonal linear polarizations.
Conclusions:
- The modified stepper motor provides a robust and accurate solution for dynamic polarization analysis.
- This device facilitates improved signal drift compensation in optical measurements.
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