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Updated: Jun 16, 2026
09:03
A Silicon-tipped Fiber-optic Sensing Platform with High Resolution and Fast Response
Published on: January 7, 2019
Summary
This study measured the refractive index of silicon at room temperature using autocollimation. The refractive index of silicon is not precisely known, with uncertainty beyond the third decimal place.
Area of Science:
- Materials Science
- Optics
- Solid State Physics
Background:
- Accurate knowledge of material properties is crucial for technological applications.
- The refractive index of silicon is a key optical parameter with implications for semiconductor devices and photonics.
Purpose of the Study:
- To measure the refractive index of silicon at room temperature.
- To evaluate the precision and limitations of current measurement techniques for silicon's refractive index.
Main Methods:
- Utilized autocollimation technique with a silicon wedge of approximately 12 degrees.
- Employed a lead sulfide cell and oscilloscope for precise image and sweep frequency detection.
Main Results:
- Measured the refractive index of silicon within the 1.1-2.0 micrometer wavelength range.
- Identified challenges and limitations in achieving high absolute precision for the refractive index measurement.
Conclusions:
- The absolute refractive index of silicon is determined to be uncertain beyond the third decimal place.
- Highlights the need for refined methodologies to enhance the accuracy of optical constant measurements in silicon.
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