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:
Nov. 29, 1994
Filed:
Oct. 25, 1990
Shinobu Ueda, Nagaokakyo, JP;
Mitsubishi Denki Kabushiki Kaisha, Kyoto, JP;
Abstract
A contrast detecting apparatus includes first extracting means for extracting a signal component of a first frequency band from a luminance signal obtained by imaging a subject, second extracting means for extracting a signal component of a second frequency band lower than the first frequency band from the luminance signal obtained by imaging the subject, and determining means for determining a state of contrast of the subject in accordance with extracted outputs of the first and second extracting means. Therefore, when the contrast detecting apparatus is used, it can be exactly and automatically determined whether the contrast of the subject exists or not in accordance with a luminance signal obtained from the subject. In addition, when the contrast detecting apparatus is applied to the automatic focusing apparatus, it is possible to control the drive of lens or information supplying means to users in accordance with whether the contrast of the subject exists or not, and as a result when the subject having no contrast is imaged, the lens is stopped to be driven so that function and operability of the automatic focusing apparatus can be improved.