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. 23, 2004
Filed:
Dec. 03, 2003
Satoshi Yahagi, Saitama, JP;
Masao Wada, Tokyo, JP;
Tetsuji Inoue, Tokyo, JP;
Ryoji Kumaki, Tokyo, JP;
Shinobu Nakamura, Tokyo, JP;
Haruo Tominaga, Tokyo, JP;
Hiroyuki Horiguchi, Tokyo, JP;
Hideaki Sugiura, Tokyo, JP;
Masayuki Sugawara, Tokyo, JP;
Other;
Abstract
A beam splitter ( )for splitting light in a wavelength range of about 500 nm to about 600 nm is arranged in a relay optical system of a taking lens ( ). A green light beam reflected from the beam splitter ( ) is directed through a relay lens (R ) to a focusing state determination imaging unit ( ). The imaging unit ( ) comprises three imaging elements (A, B, C) for capturing the directed green light beam to determine the focusing state. Thus, a device for determining the focusing state of the taking lens is provided, in which the green light beam is separated as an object light for determining the focusing state from the object light entering the taking lens ( ), so that the focusing state can be determined with high accuracy on the basis of the high-frequency components of the image signal generated by capturing the green light beam by means of the imaging elements (A, B, C) having different optical path lengths.