Abstract: A system and method for measuring the photometric retroreflectivity of materials. The system comprises a light source and a first optical pathway along which an illumination light beam travels originating from the light source, and ending at a retroreflective surface to be measured. A second optical pathway is provided along which a retroreflected beam travels back from the retroreflective surface to an aperture array that selects multiple annular areas to be further directed to multiple detectors, one detector for each annular area selected by the aperture. Each detector has a filter for the determination of photometric retroreflectivity. The retroreflected light reaching the detectors produces currents proportion to the intensity of the light. A high-gain current-to-voltage amplifier is used to provide voltage signal to an analog-to-digital converter that converts a voltage to a digital number.
Type:
Grant
Filed:
February 27, 2006
Date of Patent:
June 14, 2011
Assignee:
Belfort Instrument Company
Inventors:
Richard L. Austin, Charles L. Lustenberger, Erik Stauber
Abstract: A system and method for measuring the photometric retroreflectivity of materials. The system comprises a light source and a first optical pathway along which an illumination light beam travels originating from the light source, and ending at a retroreflective surface to be measured. A second optical pathway is provided along which a retroreflected beam travels back from the retroreflective surface to an aperture array that selects multiple annular areas to be further directed to multiple detectors, one detector for each annular area selected by the aperture. Each detector has a filter for the determination of photometric retroreflectivity. The retroreflected light reaching the detectors produces currents proportion to the intensity of the light. A high-gain current-to-voltage amplifier is used to provide voltage signal to an analog-to-digital converter that converts a voltage to a digital number.
Type:
Application
Filed:
February 27, 2006
Publication date:
May 7, 2009
Applicant:
BELFORT INSTRUMENT COMPANY
Inventors:
Richard L. Austin, Charles L. Lustenberger, Erik Stauber
Abstract: A precipitation gauge that collects liquid and frozen precipitation in a reservoir, suspended by force-sensing transducers, permitting the accurate and precise measurement of accumulated precipitation. A proportionally-heated collector assembly prevents the accumulation of frozen rain or snow on the collector inner surface, converting it into water that enters the reservoir, with minimum electrical energy consumption. The force-sensing transducer may be a programmably excited vibrating strip transducer.
Type:
Grant
Filed:
December 17, 1997
Date of Patent:
April 4, 2000
Assignee:
Belfort Instrument Company
Inventors:
Clifford Lee Greenblatt, Mellissa Jamie Stuart Dalby, Steven Mang