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:
Oct. 24, 1989
Filed:
Oct. 24, 1988
Applicant:
Inventor:
Robert F Tusting, Ft. Pierce, FL (US);
Assignee:
Harbor Branch Oceanographic Institution, Inc., Ft. Pierce, FL (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03B / ;
U.S. Cl.
CPC ...
354403 ; 354 64 ;
Abstract
Underwater photography apparatus of the type disclosed in U.S. Pat. No. 4,707,094 is improved to overcome problems from backgrounds or other 'non-clear water' conditions by inclusion of a nulling loop in the operating circuitry. Such nulling loop includes a synchronous linear modulator, an algebraic subtracter, a synchronous demodulator and a low-pass filter.