Ambient Light Calibration of a Scanning Slope Sensor

• Main Authors: Sletten, Mark A., Trizna, Dennis B., Hwang, Paul A.
• Other Authors: NAVAL RESEARCH LAB WASHINGTON DC
• Format: Text
• Language: English
• Published: 1995
• Subjects: Physical and Dynamic Oceanography; Lasers and Masers; Optical Detection and Detectors; *OCEAN SURFACE; *LASER APPLICATIONS; *OPTICAL DETECTORS; *OPTICAL SCANNING; POSITION(LOCATION); WATER; INTENSITY; LIGHT; ELECTRONIC EQUIPMENT; ILLUMINATION; SURFACES; SLOPE; CALIBRATION; NORTH ATLANTIC OCEAN; SCANNERS; AMBIENT LIGHT; PE61153N; WU53-3620-5A; North Atlantic
• Online Access: http://www.dtic.mil/docs/citations/ADA295413; http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA295413

This paper outlines a procedure developed to calibrate a laser-based water surface slope sensor against ambient light variations. An analysis of the optical position sensor used in the system indicates how variations in the ambient light intensity cause shifts in the illumination pattern centroid calculated by the sensor electronics. These shifts are misinterpreted as slope variations of the water surface unless special calibration measures are performed. The analysis is also used to illustrate a technique to compensate for this effect. The analysis is validated using laboratory and field data, and the calibration technique is then applied to data recently collected in the North Atlantic during the joint ONR/NRL HIRES program. Prepared in collaboration with QUEST Integrated, Inc., Kent, WA.