Acousto-optical system with simplified optics

Claim 2

In an acousto-optical system wherein a collimated beam of coherent light is projected from an entrance pupil to an exit pupil and in which said light beam is diffracted by a beam of sound propagating transversely to the light beam intermediate said pupils, optical apparatus comprising: a cylinder lens disposed at said entrance pupil and oriented to spread said light beam in a direction parallel to the propagation of said sound beam; means including a spherical lens confocal with said cylinder lens for recollimating said light beam in the direction of said propagation and focusing the light beam in a direction perpendicular to said sound beam; and means disposed beyond said sound beam for reshaping said light beam, including: a second spherical lens located between said sound beam and said exit pupil to concentrate the diffracted light beam in tHe direction of sound propagation; and a negative cylinder lens disposed near said exit pupil beyond said second spherical lens and oriented to recollimate said light beam in the direction of sound propagation while increasing the angle of diffraction effected by said sound beam.

Claim 3

In an acousto-optical system wherein a collimated beam of coherent light is projected from an entrance pupil to an exit pupil and in which said light beam is diffracted by a beam of sound propagating transversely to the light beam intermediate said pupils, optical apparatus comprising: means disposed ahead of said sound beam for shaping said light into a sheet-like cross-section having its longer dimension in the direction of sound propagation; a spherical lens located between said sound beam and said exit pupil to concentrate the diffracted light beam in the direction of sound propagation; and means including a cylinder lens system disposed at said exit pupil and confocal with said spherical lens for recollimating said light beam, comprising: a first cylinder lens having power in the plane of said sound beam for recollimating said light beam in that plane; and a second cylinder lens having power in a direction transverse to said sound beam for recollimating said light beam in that direction.

Claim 4

In an acousto-optical system wherein a collimated beam of coherent light is projected from an entrance pupil to an exit pupil and in which said light beam is diffracted by a beam of sound propagating transversely to the light beam intermediate said pupils, optical apparatus comprising: means disposed ahead of said sound beam for shaping said light into a sheet-like cross-section having its longer dimension in the direction of sound propagation; a spherical lens located between said sound beam and said exit pupil to concentrate the diffracted light beam in the direction of sound propagation; and means including a cylinder lens system disposed at said exit pupil and confocal with said spherical lens for recollimating said light beam, comprising: a first cylinder lens having power in the plane of said sound beam for recollimating said light beam in that plane; and a second cylinder lens having power in a direction transverse to said sound beam for recollimating said light beam in that direction.

Claim 5

For use in apparatus for operating on a collimated input laser beam including a Bragg acousto-optic cell having a predetermined direction of sound propagation, an optical system comprising: anamorphic first lens means in said input beam for forming said input beam into an elongated focus oriented orthogonal to said direction sound propagation; second lens means comprising a pair of spaced non-anamorphic components, one on each side of the acousto-optic cell, for forming an elongated image of said elongated focus at a first focal distance from said second lens means, said second lens means converging light in the plane of sound propagation in said cell to a second focus at a second focal distance from said second lens means which is less than said first focal distance; a first cylinder lens having power in the plane of said sound beam and spaced a focal length away from said image of said elongated focus for recollimating said light beam in said plane of sound propagation; and a second cylinder lens having power in a plane orthogonal to said sound beam and spaced a focal length away from said second focus for recollimating said light beam in said orthogonal plane.

Claim 6

For use in apparatus for operating on a collimated input laser beam including a Bragg acousto-optic cell having a predetermined direction of sound propagation, an optical system comprising: anamorphic first lens means in said input beam for forming said input beam into an elongated focus oriented orthogonal to said direction sound propagation; second lens means comprising a pair of spaced non-anamorphic components, one on each side of the acousto-optic cell, for forming an elongated image of said elongated focus at a first focal distance from said second lens means, said second lens means converging light in the plane of sound propagation in said cell to a second focus at a second focal distance from said second lens means which is less than said first focal distance; a first cylinder lens having power in the plane of said sound beam and spaced a focal length away from said image of said elongated focus for recollimating said light beam in said plane of sound propagation; and a second cylinder lens having power in a plane orthogonal to said sound beam and spaced a focal length away from said second focus for recollimating said light beam in said orthogonal plane.