Title:
PHOTOMETRY DEVICE FOR CAMERA
Document Type and Number:
Japanese Patent JP3475473
Kind Code:
B2
Abstract:
PURPOSE: To prevent excessive exposure and to make the reproducibility of respective colors excellent even in the case of a subject which is mostly monochrome such as red or blue by performing photometry by dividing the subject into plural color components, and calculating an exposure control value based on plural photometric values corresponding to the respective color components.
CONSTITUTION: Light passing through a photographing lens 1 is reflected by a reflection mirror 2 and forms an image on a focusing screen 3, then it passes through a pentagonal prism 4 and a photometry lens 6 and forms the image on a photometry element 7. The photometry element 7 is constituted by successively attaching color filters R, G and B to respective strip-like photosensors divided into nine, and the photometric output from the photometry element 7 is added for every photosensor, and transmitted to an exposure control part as the sensor datum DR of the R component, the sensor datum DG of the G component, and the sensor datum DB of the B component. The exposure control part 8 calculates the datum at the maximum level out of the sensor data DR, DG and DB and sets it as the exposure control value. Based on the exposure control value, a diaphragm value and shutter speed are decided to control exposure.
Inventors:
Tsuyako Matsushita
Masaru Muramatsu
Masaru Muramatsu
Application Number:
JP35272793A
Publication Date:
December 08, 2003
Filing Date:
December 28, 1993
Export Citation:
Assignee:
NIKON CORPORATION
International Classes:
G03B7/099; G03B7/28; (IPC1-7): G03B7/28; G03B7/099
Domestic Patent References:
| JP315726A |
Other References:
【文献】特許3321932(JP,B2)
Attorney, Agent or Firm:
Hisao Kamata (1 person outside)