| 摘要 |
PURPOSE:To simplify the constitution of a spectrum analyzer relatively on the whole and to reduce its size by arranging a surface acoustic wave generating means so that a surface acoustic wave which operates mutually on collimated light propagated in a semispheric light guide is generated. CONSTITUTION:The semispheric light guide 11 is formed on a substrate 10. A light source 21 such as a semiconductor laser is provided at a peripheral edge 12 (corresponding to a point P) of the semispheric light guide 11a and light emitted by the light source 21 is collimated at the bottom part of the semispheric light guide 11a, so Bragg diffraction is caused when there is an SAQ, so that the diffracted light is converted on a point different from a point Q on the peripheral edge 12. A photodetector array 24 like a CCD is arranged at the peripheral edge 12 of the semispheric light guide 11a while covering all convergence points of the diffracted light, which is photodetected. Consequently, the constitution is sipmlified, the area of the substrate may be small, and an optical circuit 42, etc., can be provided, thereby improving the degree of integration. |
