| 摘要 |
<P>PROBLEM TO BE SOLVED: To stabilize intensity control of a light source. <P>SOLUTION: A variable power supply 140 outputs a variable reference voltage. A light receiving section 120 converts received light output from a light source 110 to an electrical signal. A bias supply section 150 supplies a bias current based on an intensity control signal according to the electrical signal converted by the light receiving section 120 and on the reference voltage output from the variable power supply 140 to the light source 110. A voltage control section 180 acquires information on an intensity characteristic of the light source 110 relative to the intensity control signal, and controls the reference voltage in accordance with the acquired information on the intensity characteristic. A pulse current supply section 230 supplies a pulse current based on a constant extinction ratio control signal and the reference voltage controlled by the voltage control section 180 to the light source 110. The light source 110 outputs an optical signal of an extinction ratio depending on the pulse current supplied by the pulse current supply section 230 according to an input data signal. <P>COPYRIGHT: (C)2012,JPO&INPIT |
