| US 7,542,182 B2 | ||
| Image pickup apparatus with light emission control adapted for light-receiving characteristics | ||
| Isao Yamamoto, Kyoto (Japan); Koichi Miyanaga, Kyoto (Japan); and Takahiro Ota, Kyoto (Japan) | ||
| Assigned to Rohm Co., Ltd., (Japan) | ||
| Filed on Sep. 15, 2004, as Appl. No. 10/941,561. | ||
| Claims priority of application No. 2003-323175 (JP), filed on Sep. 16, 2003. | ||
| Prior Publication US 2005/0057786 A1, Mar. 17, 2005 | ||
| Int. Cl. H04N 1/04 (2006.01) | ||
| U.S. Cl. 358—474 [358/475; 358/509; 382/254; 382/167] | 3 Claims |
| 1. An image pickup apparatus comprising:
a plurality of light-emitting elements corresponding to respective colors;
an image pickup unit;
a boost converter for boosting an input voltage to be supplied to the light-emitting elements;
a memory for storing parameters for driving said plurality of light-emitting elements to emit a high-luminance electronic
flash light for taking photographs; and
a light-emitting circuit for reading the parameters and driving said plurality of light-emitting elements in accordance with
the parameters, wherein
the light emitting circuit comprises:
a plurality of transistors for controlling light emission of the plurality of light-emitting elements;
a plurality of operational amplifiers having their outputs respectively connected to the gates of the plurality of transistors
and having their inverting inputs respectively connected to the drains of the plurality of transistors; and
a plurality of variable constant voltage sources respectively connected to the on-inverting inputs of the plurality of operational
amplifiers and controlling the on and off of the plurality of transistors based on preset voltages determined by the parameters,
and wherein
the parameters are set so as to correct the light-receiving characteristics of said image pickup unit.
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