| 摘要 |
PURPOSE: To provide a device which optically shifts optical frequencies by setting the details of a microwave propagation line constituted by connecting two electrodes extending along waveguides with a characteristic impedance to such values that the transition of transmitted light waves from a symmetrical mode to an asymmetrical mode is made possible. CONSTITUTION: The two electrodes 424 and 425 are connected by their characteristics impedance 403 to constitute the propagation line. The progressive waves excited by voltage V (t, F) having a high frequency of about several 10GHz progress in the line. The mode conversion is accompanied with the shift of the optical frequency by as much as the value equal to the frequency of the electromagnet waves. The two waveguides 422, 423 part from each other after the distance L1 and eventually the coupling does not arise any more after the distance L1 and, therefore, the light waves which are shifted in the frequency from the incident waves and in which a phase deviation is induced are obtd. at the outputs of the waveguides 422 and 423. At this time, the phase deviation is equal toπif the conversion from the symmetrical mode to the asymmetrical mode is perfect. |
