| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent malfunction occurring when the radiation power of an optical signal or extraneous light radiated to an optical semiconductor device is strong. <P>SOLUTION: An optical semiconductor device 100 according to the present invention includes: a semiconductor substrate 50; a photo diode 70 that is formed in the semiconductor substrate 50 and generates a first photo current in accordance with the amount of light of an optical signal; a signal processing circuit 110 that is formed in the semiconductor substrate 50, and converts the first photo current into a first photo voltage and then performs arithmetic processing to the first photo voltage to generate an output signal; a dummy photo diode 71 that is formed in the semiconductor substrate 50 and generates a second photo current in accordance with the amount of leakage light of the optical signal; and a signal adjustment circuit 120 that puts the output signal into an invalid state when the second photo current is more than or equal to a predetermined threshold value. <P>COPYRIGHT: (C)2013,JPO&INPIT |
