| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical spot position controller capable of stably switching the recording layer of an optical disk. <P>SOLUTION: An optical waveguide device 20 includes a core having a first refraction index and an optical waveguide, a clad 42 holding the core 41 inside, containing an additive whose refraction index is changed when an electric field is applied and having a second refraction index smaller than the first refractive index in the non-applied state of an electric field, and an electrode pair 43 provided with two electrodes having lengths set based on the arranging interval of recording layers along the core 41 in the ouster surface of the clad 42 in the position of sandwitching the core 41 with the end of an emission end side. The control means controls the position of an optical spot by properly turning ON/OFF a voltage applied to the electrode pair 43 by a power supply device. This voltage is set to change the refraction index of an area 42a sandwitched by the electrode pair 43 to a first refraction index. <P>COPYRIGHT: (C)2007,JPO&INPIT |
