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:
Dec. 08, 1998
Filed:
Jan. 30, 1997
Minoru Takasaki, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
When a voltage signal corresponding to charges circulating a circulating shift register including charge transfer channels, which are arranged in a ring pattern, are read out from the shift register as a signal value, since clocks for circulating the charges have a very high frequency, it is difficult to operate an A/D converter in synchronism with such clocks, and a very expensive A/D converter must be used. In view of this problem, when the signal is read out, the clock frequency is lowered, and the voltage signal corresponding to the charges is converted into a digital value using an A/D converter that operates at low speed. When a distance measuring device is configured using the circulating shift register, charges corresponding to an image are shifted by the circulating shift register. In this case, since the shift efficiency is less than 100%, the amount of charges immediately after a non-charge portion decreases as they are shifted, and such charges form a false image. In order to solve this problem, the distance is calculated without using any charges immediately after the non-charge portion.