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. 09, 1998
Filed:
Mar. 26, 1997
Toshimi Watanabe, Yokohama, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A focus detection device and method permits the shooting lens to follow the movement of the photographic object without a focussing delay due to the calculation time and the movement of the object. The system includes a camera, a shooting lens, a focus detection device for detecting a desired focussing position of the shooting lens for an object, and a communications circuit. The lens includes a shooting lens driving circuit moving the shooting lens to focus, a shooting lens driving control circuit that controls the shooting lens driving circuit, a monitoring circuit that monitors the shooting lens movement by the shooting lens driving circuit, and a shooting lens data memory circuit that stores camera data. The camera includes a focal point detection circuit detecting a position of the shooting lens that matches the desired focussing position, a delay amount correction circuit updating the control amount of the amount calculation circuit to an updated control amount as a result of a delay in calculating the shooting lens control amount, and a shooting lens control amount calculation circuit calculating a control amount to drive the shooting lens to the desired focussing state, the control amount based on the focal point detection circuit detecting when the focussing position the shooting lens matches the desired focussing position and the shooting lens movement. The communications circuit communicates the lens to the with the camera. Focussing is accomplished by transmitting the updated control amount to the shooting lens and moving the shooting lens accordingly.