摘要 |
A delay circuit delays an input signal. Further, a level shift circuit, which has a variable level shift amount, is provided between the delay circuit and an OR circuit, thereby making it possible to adjust a time during which a logic of active of the delayed signal is kept. Moreover, the OR circuit performs an OR operation of the input signal and an output signal of the level shift circuit so as to obtain a signal of an OR logic, which drives a light emitting element. With this arrangement, the level shift amount is adjusted in response to a control signal externally supplied, in an optical transmitter arranged such that the input signal and output light emitted from the light emitting element with a delay in the emission, have the equal duty ratio. In this way, property unevenness among finished products of the light emitting element is cancelled out. Thus, it is possible to drive the light emitting element at a higher speed.
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