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Optical Depth Gauge for Laboratory Studies of Water Waves

Sturtevant, B. (1966) Optical Depth Gauge for Laboratory Studies of Water Waves. Review of Scientific Instruments, 37 (11). pp. 1460-1463. ISSN 0034-6748. doi:10.1063/1.1720019.

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The absorption of infrared light by water is used to measure depth. A collimated beam of light from an incandescent filament source is projected through the water from below, filtered, and detected by an infrared sensitive phototube. The quantitative performance of the gauge is assessed, and the effects of refraction and reflection at the the free surface are discussed. A circuit that linearizes the exponential dependence of the phototube output on depth is described. The sensitivity of the gauge and linearizing circuit is determined by calibration to be about 0.05 V/cm, and the smallest measurable wave amplitude, corresponding to unity signal-to-noise ratio, is about 0.07 mm. The accuracy for absolute depth measurement is about ½ mm.

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Additional Information:© 1966 The American Institute of Physics. Received 14 April 1966. Work supported in part by the Office of Naval Research under Contract Nonr 1866(20), and by the Division of Engineering and Applied Physics, Harvard University, Cambridge, Massachusetts 02138.
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Office of Naval ResearchNonr 1866(20)
Harvard UniversityUNSPECIFIED
Issue or Number:11
Record Number:CaltechAUTHORS:STUrsi66
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:12159
Deposited By: Archive Administrator
Deposited On:27 Oct 2008 22:44
Last Modified:08 Nov 2021 22:26

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