Design of glass filter combinations for photometers
Applied Optics
|January 16, 2010
Summary
Two computer programs optimize glass filters for photoelectric photometers, minimizing errors for general or specific light source measurements. This enables accurate spectral response correction with predicted errors under 0.1%.
Area of Science:
- Optics
- Photometry
- Computer Science
Background:
- Designing subtractive glass filters for photoelectric photometers requires precise spectral response matching.
- Existing methods may lack efficiency or accuracy in optimizing filter combinations.
Purpose of the Study:
- To develop nonlinear curve-fitting computer programs for designing subtractive glass filter combinations.
- To enable accurate correction of photoelectric detectors to the CIE luminous efficiency function.
Main Methods:
- Developed two nonlinear curve-fitting computer programs.
- Program 1: Adjusts filter thicknesses to minimize sum of squares of errors at each wavelength (general purpose).
- Program 2: Minimizes errors for preselected light sources (specific purpose).
Main Results:
- Specified filters for correcting various photoelectric detectors (e.g., S-4, S-10, S-11, S-20 types, silicon diodes, selenium cells) to the CIE luminous efficiency function.
- Achieved predicted measurement errors of less than 0.1% in practical photometer designs.
Conclusions:
- The developed computer programs provide an effective method for designing subtractive glass filter combinations.
- These programs facilitate the creation of accurate photoelectric photometers with minimal measurement errors.
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