MULTIWAVELENGTH LIGHT BEAM DEFLECTION AND MODULATION

摘要

MULTIWAVELENGTH LIGHT BEAM DEFLECTION AND MODULATION Apparatus and method are disclosed for diffracting light beams of different wavelengths to form a color image without achromatizing optics. An acoustic wave deflection frequency range is utilized which will result in no more than a predetermined maximum variation of diffraction efficiency and which covers the Bragg-tolerance ranges for all wavelengths used. Because the different wavelength beams will scan at different speeds (covering the same angular deflection during different scan times) intensity modulating information for each wavelength is impressed upon an acoustooptic modulator in the light path at different appropriate rates and during different appropriate periods during the scan. The modulating information for each wavelength is impressed upon the modulator only during that respective time period in which the deflection frequency is within a range that will result in angular diffraction ranges which match for all beams.