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Optical spatial intensity profiles for high order autocorrelation in fluorescence spectroscopy.
Applied Optics
|June 16, 2010
Summary
Accurate measurement of optical system profiles is crucial for spatially resolved spectroscopy. This study quantifies these profiles, enabling precise concentration measurements in complex solutions using fluorescence correlation spectroscopy.
Area of Science:
- Optical Spectroscopy
- Microscopy
- Fluorescence Correlation Spectroscopy
Background:
- Spatially resolved optical spectroscopies rely on understanding the optical excitation and collection profiles of experimental setups.
- Accurate characterization of these profiles is essential for quantitative analysis.
Purpose of the Study:
- To describe the measurement of the relative norms of the spatial profile for a combined microscope- and laser-based optical system.
- To enable accurate concentration and relative fluorescence yield measurements in multicomponent solutions using fluorescence correlation spectroscopy.
Main Methods:
- Measurement of the spatial intensity profile of a focused laser beam.
- Determination of the point collection efficiency of the microscope.
- Calculation of the relative norms of the combined optical system profile.
Main Results:
- The study experimentally determined the relative norms of the spatial profile for the described optical system.
- This quantification is vital for applying high-order autocorrelation in fluorescence correlation spectroscopy.
Conclusions:
- The experimental determination of optical system spatial profiles is essential for accurate quantitative measurements in fluorescence correlation spectroscopy.
- These findings are applicable to other optical spectroscopies, confocal microscopy, and nonlinear optics.
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