Title:
AUTOMATIC FOCAL POINT ADJUSTING DEVICE
Document Type and Number:
Japanese Patent JPS53131035
Kind Code:
A
Abstract:
Disclosed is an improvement in an automatic focusing system for use with an optical instrument having a focusable objective which is adjustable in response to optical and electronic components of the system for determining object distance of a remote subject by comparing images of scanning and reference optical systems. The scanner of the optical system is driven oscillatably across an angle to detect a subject between infinity and the minimum focus condition of the objective lens. The present invention relates to improvements in an automatic focusing system for use with an optical instrument having a focusable objective. More particularly, the improvement relates to driving the focusing system to a preset fixed focus setting when the system senses difficult conditions for focus detection as those having low contrast or complex subject matter.
Inventors:
OOSAWA NORIAKI
Application Number:
JP4519277A
Publication Date:
November 15, 1978
Filing Date:
April 21, 1977
Export Citation:
Assignee:
BELL & HOWELL JAPAN
International Classes:
G02B7/28; G02B7/30; G03B13/36; (IPC1-7): G02B7/11; G03B3/00
Domestic Patent References:
| JPS53142039A | 1978-12-11 |