Auto-iris method and apparatus for imaging device
AssigneesHitachi, Ltd., Hitachi Video & Information System, Inc.
InventorsTomoyuki Kurashige, Takuya Imaide, Hiroyuki Tarumizu
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Abstract
An auto-iris method for an imaging device includes the steps of obtaining a first signal indicating brightness of an object from a signal output from an imaging element; comparing a level of the first signal with a level of a reference signal; and enhancing a level of the reference signal more as the object becomes brighter and controlling an iris to path more quantity of light to the imaging element, based on the compared result.
Claims40
An auto-iris method for an imaging device comprising the steps of:
- (a) obtaining a first signal indicating brightness of an object to be imaged from an output signal of an imaging element;
- (b) comparing a level of said first signal with a level of a reference signal;
- and
- (c) controlling an iris to pass a larger quantity of light to said imaging element as said object becomes brighter.
An auto-iris apparatus for an imaging device comprising:
- (1) means for detecting an amplitude of a video signal generated from a signal output from an imaging element;
- (2) means for comparing a detected voltage with a reference voltage;
- and
- (3) means for controlling an iris to pass a greater quantity of light to said imaging device as said detected voltage becomes higher, based on the output of said comparing means.
An auto-exposure control method for an imaging device, comprising the steps of:
- (a) obtaining a first signal indicating brightness of an object to be imaged;
- (b) obtaining a second signal corresponding to a level of a first video signal obtained from an output signal of an imaging element;
- (c) comparing a level of said second signal with a level of a reference signal;
- and
- (d) controlling an exposure on the basis of said first signal via said comparing step such that as said object becomes brighter, a level of a second video signal, which is outputted from said imaging device, becomes larger.
An auto-exposure controlling apparatus for an imaging device, comprising:
- (1) an iris for controlling the amount of light which reaches an imaging element;
- (2) means for driving said iris;
- (3) means for outputting a first signal indicating brightness of an object to be imaged;
- (4) means for outputting a second signal corresponding to a level of a first video signal obtained from an output signal of said imaging element;
- (5) means for comparing the level of said second signal with a reference voltage, and for outputting a signal to said means for driving said iris;
- and
- (6) means for controlling an exposure on the basis of said first signal such that as the brightness of said object increases, a level of a second video signal, which is outputted from said imaging device becomes larger.
Dependencies are inferred from the claim text.