Exposure calculating apparatus

Patent 5392091 Issued on February 21, 1995. Estimated Expiration Date:

August 24, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Patent #: 4445778
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Patent #: 5253008
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Automatic exposure control apparatus with improved exposure value calculation for photographing a moving object
Patent #: 5255044
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Exposure control device Patent #: 5272538
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Inventor

Iwasaki, Hiroyuki

Assignee

Nikon Corporation

Application

No. 933819 filed on 08/24/1992

US Classes:

396/234More than two photometering areas

Examiners

Primary: Perkey, W. B.

Attorney, Agent or Firm

Shapiro and Shapiro

Foreign Patent References

63-94232 JP. 04/25/1988
2-32312 JP. 02/25/1990

International Class

G03B 007/28

Foreign Application Priority Data

1991-08-27 JP

Abstract

An exposure calculating apparatus includes a light-metering device, consisting of a light-metering elements corresponding to elementary areas obtained by dividing a field of a focusing optical system, for measuring a light intensity distribution in the field, a position of object detecting means for detecting a position of object in the field, a classifying means for changing a divisional pattern of light-metering areas in correspondence with the position of object, and classifying the light-metering elements of the light-metering device into a plurality of groups according to the divisional pattern, and a calculating device for calculating an exposure value by weighting the outputs from the plurality of light-metering elements in correspondence with the groups to which the light-metering elements belong, and supplying the exposure value to exposure control.