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:
Feb. 12, 1991
Filed:
Jul. 31, 1989
Shigeki Nishizawa, Mobara, JP;
Toshio Miyazawa, Chiba, JP;
Iwao Takemoto, Mobara, JP;
Tetsuro Izawa, Mobara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A noise reduction circuit receives a periodic signal from an imaging device, and includes first and second circuits in which noise components opposite in phase are offset by delaying the input signal to produce a delayed signal and adding the delayed signal and the input signal. The output of the first circuit is supplied to a low pass filter, while the output of the second circuit is integrated through a first high-pass filter for a time wherein an output signal representing the sum of the input signal and the delayed signal is generated and is then outputted through a second high pass filter. Output signals of the low-pass filter and the second high-pass filter are then added and the result is outputted as a signal free noise.