Flash tube apparatus with delayed emission
AssigneeNippon Kogaku K.K.
InventorHiroshi Hasegawa
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Abstract
A flash tube (speed-light) apparatus is provided with a drive circuit for ionizing gas in the flash tube in response to a triggering voltage produced by a trigger coil, and a light-measuring circuit measures the light emitted by the flash tube and reflected by an object to be photographed and controls the quantity of light emitted by the flash tube. The drive circuit comprises delay means that delays the flash emission by a predetermined delay time commencing with the energizing of the trigger coil. The delay time is selected longer than a period during which the light-measuring circuit is affected by noise generated by the energizing of the trigger coil.
Claims6
In flash tube apparatus comprising a drive circuit for ionizing gas in a flash tube by means of a trigger circuit, thereby causing flash discharge in said flash tube, and comprising a light-measuring circuit for measuring the light emitted by said flash tube and reflected by an object to be photographed and for controlling the light emitted by said flash tube, said light-measuring circuit being susceptible to erroneous operation caused by noise generated upon energizing of said trigger circuit, the improvement wherein said drive circuit includes delay means for delaying the flash emission from said flash tube until the lapse of a predetermined delay time commencing with the energizing of said trigger circuit, said delay time being longer than a period during which said light-measuring circuit may be adversely affected by noise generated upon the energizing of said trigger circuit.
Dependencies are inferred from the claim text.