Acoustic light deflection method

Claim 1

In the method of deflecting a light beam by acoustic Bragg deflection in an optical system having an arbitrarily defined xaxis, y-axis and optic axis normal to each other, and, located in succession, at least one light source for generating a light beam directed generally parallel to said optic axis through a collimating lens for collimating said beam to an acoustic Bragg cell for deflecting said beam to an imaging lens for imaging said deflected beam, said light source being located along said y-axis so as to generate a light beam which after collimation has a wavefront varying from parallel to the x-y plane when said light source is located at said optic axis to a wavefront having an angle phi with the x-y plane when located off the optic axis and along the y-axis at a point P, where phi equals the distance said light source is offset from the optic axis divided by the focal length of said collimating lens, the improvement comprising: generating in said acoustic deflection cell acoustic waves traveling in a direction making an angle Alpha , with the xaxis, with the acoustic wavefronts making an angle Alpha with the y-z plane, and parallel to the y-axis to create an angle theta between the optical and acoustic wavefronts defined by cos theta sin Alpha . cos phi , whereby the effective Bragg angle Beta between the acoustic wave front and the principal ray of the light beam originating from P being is such that sin Beta sin Alpha . cos Beta , with the change Delta Beta due to a maximum change phi given by so that various collimated beams originating from light sources located at different points along the y-axis making different angles phi with the optic axis, simultaneously fulfill the Bragg-angle conditions with respect to the acoustic wavefronts and may be deflected to any one of a predetermined number of deflection positions perpendicular to the y-axis as a function of the acoustic frequency of the Bragg cell.

Claim 5

A method of focusing and deflecting light to allow track formation upon the surface of a moving object, comprising the steps of: defining an x-axis, axis and optic axis normal to each other, locating in succession along said optic axis at least one light source for generating a light beam directed generally along said optic axis to a collimating lens for collimating said beam to an acoustic Bragg cell for deflecting said base to an imaging means for imaging said deflected beam, said light source being located along said y-axis so as to generate a light beam which after collimation has a wavefront varying from parallel to the x-y plane when said light source is located at said optic axis to a wave front having an angle phi with the x-y plane when located off the optic axis and along the y-axis at a point P, where phi equals the distance said light source is offset from the optic axis divided by the focal length of said collimating means, generating in said acoustic deflection cell acoustic waves traveling in a direction making an angle Alpha with the x-axis, with the acoustic wavefronts making an angle Alpha with the y-z plane, and pArallel to the y-axis to create an angle theta between the optical and acoustic wave fronts defined by cos theta sin Alpha . phi , and locating said surface of said moving object in an angular, non-normal relationship to the y-axis upon which said light sources are located, whereby a plurality of light tracks separate from each other are generated upon said surface of said moving object as a function of deflection positions of each of said light sources.

Claim 6

A method of focusing and deflecting light to allow track formation upon the surface of a moving object, comprising the steps of: defining an x-axis, axis and optic axis normal to each other, locating in succession along said optic axis at least one light source for generating a light beam directed generally along said optic axis to a collimating lens for collimating said beam to an acoustic Bragg cell for deflecting said base to an imaging means for imaging said deflected beam, said light source being located along said y-axis so as to generate a light beam which after collimation has a wavefront varying from parallel to the x-y plane when said light source is located at said optic axis to a wave front having an angle phi with the x-y plane when located off the optic axis and along the y-axis at a point P, where phi equals the distance said light source is offset from the optic axis divided by the focal length of said collimating means, generating in said acoustic deflection cell acoustic waves traveling in a direction making an angle Alpha with the x-axis, with the acoustic wavefronts making an angle Alpha with the y-z plane, and pArallel to the y-axis to create an angle theta between the optical and acoustic wave fronts defined by cos theta sin Alpha . phi , and locating said surface of said moving object in an angular, non-normal relationship to the y-axis upon which said light sources are located, whereby a plurality of light tracks separate from each other are generated upon said surface of said moving object as a function of deflection positions of each of said light sources.