Multiple-channel information translation system and method

A multiple-channel information translation system for receiving a spatially coherent input light beam and a plural number greater than two of electrical input signals and for producing therefrom a like plural number of output light beams each bearing amplitude information corresponding to one of said input signals, comprising:

• carrier generating means for generating a plural number greater than two of electrical carriers each having a different RF frequency;
• modulating means for respectively amplitude modulating said carriers with the input signals to produce a like plural number of amplitude-modulated carrier signals;
• and
• a Bragg light-sound interaction cell interposed in the path of the input light beam, said cell including a sound-propagative medium and transducer means coupled to said sound-propagative medium which receives said carrier signals and launches within said medium a corresponding plural number of sound beams, each having a sound frequency and amplitude modulation corresponding to a different one of said carrier signals, said cell Bragg-diffracting the input beam into a corresponding plural number of output light beams respectively amplitude modulated in accordance with the input signals,
• said carrier generating means causing the frequencies of said carriers to be unequally spaced and such that the frequency differences between each carrier frequency and all others are unequal so as to suppress cross-channel interference effects in said cell and thereby to suppress random, signal-related spurious amplitude modulation of said output light beams.

A laser character generating system for receiving a laser beam and electrical input signals representing image information and for producing therefrom light-formed images for recording or display, comprising:

• carrier generating means for generating a plural number greater than two of electrical carriers each having a different RF frequency;
• modulating means for receiving image information and for respectively amplitude modulating said carriers with the input signals so as to produce a like plural number of amplitude-modulated carrier signals each characterizing a different line in a raster of image lines defining an image to be displayed or recorded;
• a Bragg light-sound interaction cell interposed in the path of the input light beam, said cell including a sound-propagative medium and transducer means coupled to said sound-propagative medium which receives said carrier signals and launches within said medium a corresponding plural number of sound beams each having a sound frequency and amplitude modulation corresponding to a different one of said carrier signals, said cell Bragg-diffracting the input beam into a corresponding plural number of coplanar, angularly separated output light beams respectively amplitude modulated in accordance with the input signals;
• and
• means for deflecting said output light beams as a fan of beams in a direction perpendicular to the plane containing said beams so as to simultaneously sweep out a raster of image lines defining an image at an output plane,
• said carrier generating means causing the frequencies of said carriers to be unequally spaced and such that the frequency differences between each carrier frequency and all others are unequal so as to suppress cross-channel interference effects in said cell tending to produce random, signal-related spurious amplitude modulation of said output beams.

A laser character generating system for receiving a laser beam and electrical input signals representing character information and for producing therefrom light-formed alphanumeric characters for recording or display, comprising:

• carrier generating means for generating a plural number greater than two of electrical carriers each having a differennt RF frequency;
• modulating means for receiving the input signals representing character information and for respectively gating said carriers with the input signals so as to produce a like plural number of gated carrier signals, each characterizing a different line in a raster of image lines defining a line of characters;
• a Bragg light-sound interaction cell interposed in the path of the input light beam, said cell including a sound-propagative medium and transducer means coupled to said sound-propagative medium which receives said carrier signals and launches within said medium a corresponding plural number of sound beams each having a sound frequency and amplitude characteristic corresponding to a different one of said carrier signals, said cell Bragg-diffracting the input beam into a corresponding plural number of coplanar, angularly separated primary output light beams respectively gated in accordance with the input signals;
• and
• means for deflecting said output light beams as a fan of beams in a direction perpendicular to the plane containing said beams so as to simultaneously sweep out a raster of image lines defining a line of characters at an output plane,
• said carrier generating means causing the frequencies of said carriers to be unequally spaced and such that the frequency differences between each carrier frequency and all others are unequal so as to suppress cross-channel interference effects in said cell tending to produce random, signal-related spurious amplitude modulation of said output beams.

A method for generating and presenting images or alphanumeric characters from an input laser beam and electrical input signals representing image or character information, comprising:

• generating a plural number greater than two of electrical carriers, each having a different RF frequency;
• amplitude modulating each of said carriers respectively with an input signal so as to produce a like plural number of modulated carrier signals each characterizing a different line in raster of image lines defining an image or a line of characters to be presented;
• supplying said carrier signals to a Bragg light-sound cell and Bragg-diffracting at least part of the input laser beam into a like plural number of coplanar, angularly separated first order output light beams, each amplitude-modulated in accordance with a different one of said input signals;
• and
• deflecting said output light beams as a fan of beams in a direction perpendicular to the plane containing said output beams so as to simultaneously sweep out a raster of image lines defining an image or a line of characters at an output plane,
• said method being characterized by selecting the frequencies of said carriers to be unequally spaced and such that the frequency differences between each carrier frequency and all others are unequal so as to suppress cross-channel interference effects in said cell tending to produce random, signal-related spurious amplitude modulation of said output beams.