| 摘要 |
PURPOSE:To obtain a set frequency band by setting up a part having an inter-electrode finger interval corresponding to frequency levels on both the ends of a frequency band included in a surface acoustic wave to a value longer than a part having an inter-electrode finger interval corresponding to other frequency levels. CONSTITUTION:A surface acoustic wave electrode for shifting respective frequency areas in the frequency band included in the electrode in a direction parallel with the transmitting direction of light 3 is used. In order to obtain the frequency band coincident with a designed value in the surface acoustic wave electrode, i.e. in order to prevent the deterioration of efficiency of polarized light due to surface acoustic waves at the frequency levels on both the ends of the frequency band and its vicinity, the parts DH, DL having the interval between the electrode fingers 1 corresponding to the frequency levels fH, fL on both the ends of the frequency band, i.e. the electrode finger parts mose the close to electrode pads 2, are set up to a value longer to the part having the interval of electrode fingers corresponding to other frequency levels. Consequently, a light deflector/modulator having the set frequency band can be attained without generating the deterioration of projection yield and that of the frequency band.
|
