| 摘要 |
PURPOSE:To improve SN ratio and plan the improvement of receiving sensitivity without crosstalking and interfering from transmitter to transmitter by electromagnetically separating a receiving circuit and a transmitting circuit with a shield inner layer and a shield case and electromagnetically taking away a light receiving element and a light transmitting element each other. CONSTITUTION:A shield inner layer 2 is provided in a printed wiring board 1, the outer circumferential surface of the printed wiring board 1 is covered by a shield case 5, and a receiving circuit 15 and a transmitting circuit 25 are electromagnetically separated each other. Thus, crosstalk is eliminated from the transmitting circuit 25 to the receiving circuit 15. Further, since a light receiving element 10 including a light receiving element terminal 11 and a light transmitting element 20 including a light transmitting element terminal 21 are electromagnetically separated by a receptacle case 40, a partition plate 41 and a shield plate 45 each other and shielded, electric field from a transmitter and especially a light transmitting element terminal 21 is applied on a light receiving element terminal 11 and SN ratio of a receiver is high without interference by crosstalk. |
