| 摘要 |
PURPOSE:To realize the optical communication system with a high degree of freedom of a form of an optical signal by attaining accurate and long distance information transmission sending lots of information while excluding the effect of an external disturbance light. CONSTITUTION:An optical signal IS1 sent from a current-optical conversion element 12 of an optical transmitter 1 radiates to space as a linearly polarized optical signal OS2 via a polarizer 13. A 1st optical-current conversion element 22 and a 2nd optical-current conversion element 26 of an optical receiver 2 convert an incoming light respectively into electric signals ES3, ES4. However, the 1st optical-current conversion element 22 receives a light passing through a 1st optical system 21 having no polarized light characteristic and the 2nd optical-current conversion element 26 receives a light passing through a 2nd optical system 25 having a polarized light characteristic respectively. Then the electric signals ES3, ES4 amplified by a prescribed amplification factor set relatively so as to compensate a difference of an attenuation with respect to an external disturbance light in the 1st optical system 21 and the 2nd optical system 25 by a 1st amplifier circuit 23 and a 2nd amplifier circuit 27 are differentially amplified by a differential amplifier circuit 24. |
