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:
Jun. 03, 2003
Filed:
Jun. 19, 2001
Takayuki Sensui, Tokyo, JP;
Pentax Corporation, Tokyo, JP;
Abstract
A focus detection apparatus includes a pupil dividing device for dividing an exit pupil of an objective lens into separate areas, a field mask located at a position substantially optically equivalent to an image forming position of the objective lens, a condenser lens located in the vicinity of the field mask to make the exit pupil conjugate with the pupil dividing device, a light quantity distribution forming device for receiving light transmitted through the separate areas and forming light quantity distribution portions wherein the relative position of the light quantity distribution portions varies in accordance with a focus state of the objective lens, and a focus detection apparatus having at least one group of photoelectric transducers which receive the light quantity distributed by the pupil dividing device. The condenser lens is moved in accordance with the position of the exit pupil of the objective lens.