The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 01, 1990
Filed:
Jun. 30, 1987
Applicant:
Inventor:
L Willard Richards, Santa Rosa, CA (US);
Assignee:
Sonoma Technology, Santa Rosa, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
356229 ; 356438 ;
Abstract
A photographic method of collecting and reducing photographic film density data for monitoring air quality is disclosed in which photographic film is first calibrated using calibration scales of known reflectance and the measured radiance of one calibration scale step to relate the photographic film density to the known radiance. Measurement of a target's radiance and sight path radiance is made via target photographic image density analysis and mathematical expressions which convert density information into radiance and/or atmospheric transmittance data using expressions developed from the calibration scale data.