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Infrared modulation by means of frustrated total internal reflection
R W Astheimer1, G Falbel, S Minkowitz
1Barnes Engineering Company, Stamford,Connecticut, USA.
Applied Optics
|January 6, 2010
Summary
This study presents a novel infrared modulation cell using frustrated internal reflection, eliminating mechanical parts for space applications. It achieves 80% modulation of 10-micrometer radiation with a high-frequency response.
Area of Science:
- Optics and Photonics
- Infrared Technology
- Mechanical Engineering
Background:
- Traditional infrared systems rely on mechanical choppers or scanners.
- Space applications necessitate the elimination of sliding or rotating mechanical components.
- Frustrated internal reflection offers a non-mechanical modulation alternative.
Purpose of the Study:
- To develop and characterize a novel modulation cell for infrared radiation.
- To eliminate mechanical components in infrared modulation systems for space suitability.
- To demonstrate the practicality of frustrated internal reflection in the 8-12 micrometer range.
Main Methods:
- Utilized the principle of frustrated internal reflection for radiation modulation.
- Constructed a modulation cell with a 12.7 mm clear aperture.
- Employed a lead zirconate titanate piezoelectric stack for precise element movement.
Main Results:
- Achieved 80% modulation of 10-micrometer infrared radiation.
- Demonstrated the feasibility of controlling motions at the 0.05 wavelength scale in the infrared spectrum.
- Obtained a frequency response exceeding 6 kHz.
Conclusions:
- Frustrated internal reflection is a practical method for infrared modulation, especially in the 8-12 micrometer range.
- The developed modulation cell effectively replaces traditional mechanical systems.
- The piezoelectric-driven cell offers high-frequency response suitable for demanding applications.
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