| 摘要 |
PURPOSE:To obtain a large angle of deflection by providing means for generating light deflection within the waveguide plane in an optical waveguide and forming the grating in an output part in such a manner that the period thereof changes continuously to a sectorial shape. CONSTITUTION:The thin-film waveguide 2 is provided on the substrate 1 and one end face 3 thereof is used as an input part. The output part 4 consisting of the grating, the period of which is changed continuously to the sectorial shapes provided at the point of the prescribed distance from the input part. Electrodes 5 for generating surface acoustic waves are provided between the input part and the output part and the light deflection is executed within the waveguide plane to change the progressiing direction of the light in the waveguide. A laser beam is made incident from the end face 3 and propagates in the thin-film waveguide 2. The guided light is deflected by alpha deg. when an electric field is impressed to the electrodes 5 for generating the surface acoustic waves. As a result, the exit light emitted at theta with respect to the perpendicular line from the point B in the absence of the electric field impression is emitted from the point A. The period of the grating at the point A is smaller than the period at the point B and, therefore, the exit light is eventually emitted at thetaA with the perpendicular line and is largely deflected by theta deg.. |
