| 摘要 |
PURPOSE: To suppress skew to a minimum by providing a controller for previously lowering the signal identification level of an identification device to the half of the intermediate value of maximum and minimum values among optical signal levels from (n) pieces of light emitting elements corresponding to the output signal of an amplifier for monitor current reception before a communicating operation. CONSTITUTION: This equipment is provided with plural light receiving elements 131 -13n for monitoring the optical signals from (n) pieces of light emitting elements 111 -11n , these plural monitor output currents are added, light is emitted corresponding to the amplified current, and optical signals are transmitted to the reception side. In this case, the skew value between signals caused by dispersion in the turn-on levels of light emitting elements is largest among the signals to be communicated at the maximum and minimum values among the turn-on levels of light emitting elements 111 -11n . However, since the signal identification level is controlled to be 1/2 of the intermediate value to become the average value of those maximum and minimum values, the signal identification level can be turned to the best value so that the dispersion in the turn-on levels of light emitting elements 111 -11n can be suppressed and the skew between the respective signals caused by the dispersion in the turn-on levels of light emitting elements can be made minimum. |
