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Updated: Jul 2, 2026
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Fluorescence polarization: measurements with a photon-counting photometer
D M Jameson1, G Weber, R D Spencer
1Biochemistry Department, University of Illinois, Urbana, IL 61801, USA.
The Review of Scientific Instruments
|April 1, 1978
Summary
A new photon-counting polarization photometer enables precise polarization measurements even with weak signals. This instrument is validated for sensitive detection of fluorescein and indole polarization spectra.
Area of Science:
- Instrumentation
- Photochemistry
- Spectroscopy
Background:
- Precise polarization measurements are crucial in various scientific fields.
- Low signal-to-noise ratios often challenge traditional polarization instrumentation.
- Advancements in photon-counting technology offer potential for improved sensitivity.
Purpose of the Study:
- To design and construct a T-format, photon-counting polarization photometer.
- To achieve precise polarization measurements at low signal-to-noise ratios.
- To demonstrate the instrument's performance with sensitive biological and chemical samples.
Main Methods:
- Construction of a novel T-format polarization photometer utilizing photon-counting detection.
- Detailed description of the instrument's optical and electronic components.
- Performance evaluation using picomolar fluorescein solutions and indole at specific spectral resolutions.
Main Results:
- The constructed instrument facilitates accurate polarization measurements under low signal conditions.
- Successful measurements were achieved for picomolar fluorescein solutions.
- The excitation polarization spectrum of indole was successfully obtained with high spectral resolution (5 A).
Conclusions:
- The developed photon-counting polarization photometer is effective for high-precision measurements.
- The instrument demonstrates significant sensitivity, suitable for analyzing low-concentration samples.
- This technology advances the capabilities for spectroscopic and photochemical research.
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