Discussed are the specifications for a Photometric Standard of Hard Dot Area. Mathematical approximations have determined the desired pattern and frequency to be; cross hatch and 100 lines/in. respectively. When measuring the Photometric Standard, deviation from the actual area is attributed to micromotion in the aperture and diffraction in the Densichron 3885d (Sargent - Welch Scientific Co.). The desired specifications in the Photometric Standard allow precise measurements of ± 5% area. A Hard Dot Area Meter was designed and constructed, which simulates a photometric method that theoretically eliminates deviation from the actual area measured. It was statistically tested against microscopic measurements of the Photometric Standard.
Library of Congress Subject Headings
H. Brent Archer
Misar, Steven K., "Calibration of a Photometric Standard for Hard Dot Area measurement" (1972). Thesis. Rochester Institute of Technology. Accessed from
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