US PATENT SUBCLASS 396 / 213
EXPOSURE CONTROL CIRCUIT


Current as of: June, 1999
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396 /   HD   PHOTOGRAPHY

213EXPOSURE CONTROL CIRCUIT {23}
214  DF  .~> Clamp or stop needle control device {2}
217  DF  .~> Direct drive galvanometer control device {3}
221  DF  .~> Responsive to power source condition
222  DF  .~> Bracketing
223  DF  .~> Override control
224  DF  .~> Photometer lock
225  DF  .~> Color temperature compensation or detection
226  DF  .~> Film latitude responsive
227  DF  .~> Maximum or minimum f-number responsive
228  DF  .~> Having log transformation circuit {2}
231  DF  .~> Having temperature compensation circuit
232  DF  .~> Viewfinder light compensation
233  DF  .~> Having plural photocells {1}
235  DF  .~> Velocity control of shutter or diaphragm component
236  DF  .~> Look-up table memory
237  DF  .~> Manually set limit of exposure time or aperture value
238  DF  .~> Manually selective exposure mode {1}
240  DF  .~> Pulse train type
241  DF  .~> With exposure filter
242  DF  .~> Program mode {2}
245  DF  .~> Manual Av circuit with automatic Tv circuit, or vice versa
246  DF  .~> Shutter speed function only {6}
257  DF  .~> Diaphragm function only {4}


DEFINITION

Classification: 396/213

EXPOSURE CONTROL CIRCUIT:

(under the class definition) Subject matter having electric circuit means to control a shutter, a diaphragm, or another optical element; e.g., a light filter for regulating the amount of light reaching a photos:graphic medium or film.

SEE OR SEARCH THIS CLASS, SUBCLASS:

48, for control circuit for sequencing at least three functions which may include exposure control.

63+, for exposure control system responsive to focal length.

65+, for exposure control system responsive to distance.

100, for photocell used for another purpose besides focusing or rangefinding.

161, for camera structure with artificial illumination termination control including exposure control circuit.

166+, for exposure control circuit with illumination mode. 171, for photocell that responds to a burst of light for starting a flash operation or for camera release.

180+, for camera structure with object illumination and exposure synchronizer.

263+, for a generic release control electrical circuit.

, FOR 710+, for foreign art collections involving camera automatic exposure control system or device.

SEE OR SEARCH CLASS

136, Batteries: Thermoelectric and Photoelectric,

243+, for photoelectric devices, per se.

250, Radiant Energy,

200+, for generic photocell circuits.

313, Electric Lamp and Discharge Device,

523+, for photosensitive devices and subclasses 103+ for photosensitive devices having secondary emitters. 348, Television,

221, 229, and 362+ for exposure control in video camera.

352, Optics: Motion Pictures,

141, and 177 for automatic diaphragm or shutter control in motion picture camera.

356, Optics: Measuring and Testing,

213+, for photometers.

399, Electrophotography,

51+, for control of exposure in an electrophotos:graphic device.