| 摘要 |
PURPOSE:To deflect light over a wide angle range without inclusion of zero-order light by applying the signal reciprocatively changing in a prescribed frequency range to a transducer, selectively entering two luminous fluxes in correspondence to this and deflecting the same to different regions. CONSTITUTION:An optical waveguide 21 is formed on the surface of a piezoelectric crystal plate 20 of LiNbO3 or the like by diffusing Ti, and two semiconductor lasers 25, 26 are disposed to the incident end surface thereof. The respective luminous fluxes thereof are diffracted in the ultrasonic field through a thin film lens 27. Two sets of comb-shaped electrodes 29, 30 are inclined by a prescribed angle and are symmetrically disposed. When the signal of which the frequency changes continuously from f2 up to f1 is aupplied to the electrode 29 and a luminous flux 22 is entered, a deflected luminous flux 31 is obtained in the direction going apart from zero-order light (e). When the signal changing from frequency f1 up to f2 is applied to the electrode 30, and a luminous flux 23 is entered in succession to this, a deflected luminous flux 33 in the direction going apart from zero-order light (d) is obtained. Hence, the light is deflected in a wide angle range without inclusion of zero-order light. |
