Title:
【発明の名称】測光回路
Document Type and Number:
Japanese Patent JP2542087
Kind Code:
B2
Abstract:
PURPOSE:To obtain a pickup pattern suitable for the situation by providing a means limiting an input to a photometric circuit and excluding an input picture signal from an object of photometry when the level of the input picture signal is higher than a prescribed level and its consecutive time has a prescribed period. CONSTITUTION:A picture signal is integrated at a prescribed time constant by a photometry integration device 56 and the result is outputted as a control signal for an AGC circuit and an aperture control circuit or the like. Moreover, the picture signal is fed to an input terminal of an integration device 51 and a comparator 54. An output signal of the comparator 54 is normally at an L level and but at an H level only for a period td when a picture signal level is considerably high. A switch 55 is closed when the output signal of the comparator 54 is at an L level and opened when at an H level. Thus, the picture signal is not fed to the photometry integration device 56 for the period td when a picture signal level is considerably high and the picture signal is excluded from an object of photometry.
Inventors:
TSUJI KYOSHI
OKADA SACHIHIRO
OKADA SACHIHIRO
Application Number:
JP24749389A
Publication Date:
October 09, 1996
Filing Date:
September 22, 1989
Export Citation:
Assignee:
OLYMPUS OPTICAL CO
International Classes:
A61B1/04; H04N5/225; H04N5/235; (IPC1-7): H04N5/235
Domestic Patent References:
| JP60165180A | ||||
| JP62248382A |
Attorney, Agent or Firm:
Susumu Ito