| 摘要 |
Optoelectrical polarisation-dividing/combining change- over switch on a wafer of double-refracting crystal material with an optical axis Z. The change-over switch has a region of interaction L1 with optical waveguides 3, 4 and an electro-arrangement. The region of interaction L1 is divided into two sections S1, S2 with a central electrode 6; 9 and two outer electrodes 5, 7; 8, 10 in each section. Connected to the electrodes are voltage sources 12, 13, 14; 15, 16, 17 which generate electric fields through the optical waveguides 3, 4. The electric field between the outer electrodes 5, 7; 8, 10 has in each section S1, S2 the same direction in both the optical waveguides and brings about δχ modulation. The electric field between the central electrode 6; 9 and the outer electrodes 5, 7; 8, 10 has in each section S1, S2 mutually opposite directions in the two optical waveguides and brings about a δβ modulation. In this way, one mode (the TM mode) of the light is cross-coupled and the other mode (the TE mode) of the light is through-coupled in the case of an arbitrarily polarized light wave P. The device can be operated with low voltages and the necessary manufacturing precision is relatively low. <IMAGE> |
