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Class 396/254 - Including plural selective resistors


Subclass of Class 396 - Photography
Definition: Subject matter having multiple resistors from which to choose.
No. of patents: 10
Last issue date: 09/12/2006


NumberTitleIssue Date
7104708Sector drive unit for camera
A sector drive unit for a camera includes sectors capable of opening and closing an aperture provided on a base plate. A first actuator drives the sectors to open and close the aperture, and a drive force transmitting mechanism transmits a driving force of the first...
09/12/2006
4213683Electronic shutter driving device for camera
An electronic shutter driving device has a logarithmic expansion circuit which includes no semiconductor element such as a transistor and a field-effect transistor and comprises an operational amplifier, a series of resistors connected to an inverting inp...
07/22/1980
4189221Electrical shutter circuit
An electrical shutter control circuit of the type which is integrated directly is disclosed. The light receiving element is connected across the input terminals of an operational amplifier, and a switch connects one of at least two integrating capacitors ...
02/19/1980
4140379Electronic exposure timing circuit for photographic cameras
The camera shutter is opened. An electromagnet is energized to keep the shutter open. A first timing circuit includes a photosensitive element exposed to scene light through which a timing capacitor charges. The voltage across the timing capacitor is appl...
02/20/1979
4089015Dual function exposure time display and control circuit for SLR camera
A light meter circuit for an SLR camera implements full aperture viewfinding with a preselected exposure time by providing an integrating capacitor 25 for controlling the exposure time, a first switch 24 for enabling the charging of the capacitor, circuit...
05/09/1978
4083059Automatic exposure control system for flash photography
In a camera provided with a day-light exposure range and with a flash exposure range, an automatic exposure control system for controlling the iris of the camera in accordance with a computed exposure value and a preselected shutter time is associated wit...
04/04/1978
4072961Light measuring circuit for automatic exposure control
Light measuring circuit for camera automatic exposure control measures scene light passing through the objective and reflected at the film surface and/or the shutter curtain surface located at the exposre aperture of the camera. The measuring circuit is p...
02/07/1978
4045806Extended range exposure control system
An extended range exposure control system for photographic cameras having an aperture plate slidably movable from a first position in which it stops down the maximum relative aperture of the camera lens to second and third positions in which a photographi...
08/30/1977
4040068Exposure time control device for an electric shutter in a single reflex camera with through the lens measuring system
A control device for controlling the exposure time automatically for an electric shutter, in a single reflex camera of the so-called "through the lens" photometric type which determines the brightness of an object by means of the light past through the pr...
08/02/1977
4007467Exposure control circuit
A light-sensitive element is connected to a capacitor to vary the charging rate of the capacitor in accordance with the light falling on the light-sensitive element. The emitter-collector circuit of a switching transistor is connected in series with the l...
02/08/1977
 
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