Lens and aperture control apparatus

Details Lens and aperture control apparatus Lens and aperture control apparatus

1990-10-17

1993-03-16

Groody, James J.

Facsimile and static presentation processing

Facsimile

Recording apparatus

358227, 358228, 358225, H04N 5232, H04N 5238

Patent

active

051949563

ABSTRACT:
Lens control apparatus for use in a video camera in which an object is imaged through an adjustable lens onto an image pick-up element from which a video signal is derived. The lens is driven for focus or zoom adjustments by servo control at a rate determined by the synchronizing signal included in the video signal. The aperture of the video camera also is controlled by detecting the amount of light which impinges on the image pickup element and then determining the ratio between the detected light level and a reference level representing the brightness of the object. The aperture is driven (i.e. it is enlarged or reduced) as a function of the product of the aforementioned ration and a coefficient which changes with the aperture opening. When the aforementioned ratio is less than unity, the coefficient increases as the aperture opening decreases and, conversely, decreases as the opening increases. When the ratio is greater than unity, the coefficient increases as the aperture opening increases and, conversely, decreases as the opening decreases.

REFERENCES:
patent: 4638350 (1987-01-01), Kato
patent: 4672456 (1987-06-01), Murai
patent: 4717959 (1988-01-01), Isago
patent: 4754333 (1988-06-01), Nara
patent: 4903135 (1990-02-01), Ohtake
patent: 4935763 (1990-06-01), Itoh
patent: 4967281 (1990-10-01), Takada
patent: 4969044 (1990-11-01), Hijikata
patent: 4985777 (1991-01-01), Kawada
patent: 4998162 (1991-03-01), Kondo

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