Patent ID: 7891821

Claim:
Apparatus for projecting a laser-beam delivered by a laser located at a fixed distance from the apparatus, said laser beam characterized as having a transverse X-axis and a transverse Y-axis perpendicular to each other and propagating in a longitudinal Z-axis perpendicular to both of the transverse axes, wherein the laser-beam has a characteristic beam-waist size within a Rayleigh range, the Rayleigh range being characterized as the length of the beam between points therein at which the beam has a beam size that is about the square-root-of-2 times the beam-waist size, the apparatus comprising: a first stack of plates arranged at an angle to each other for slicing the laser beam in the X-axis into a plurality of beam-slices and spreading the slices parallel to the Y-axis direction with the spread of slices; a second stack of plates arranged to align the Y-axis-spread beam-slices along the X-axis; a beam-projector including a lens having optical power in at least the X-axis and arranged to project the Y-axis aligned and spread beam-slices into a line of radiation about in an X-axis focal plane of the lens such that the line of radiation has a length in the Y-axis and a width in the X-axis; and a telescope having first and second optical elements having a selectively variable Z-axis spacing therebetween and wherein varying the spacing between the optical elements varies the Z-axis position of the Rayleigh range with respect to the stacks of plates in a manner so that the Rayleigh range is about centered in the Z-axis over the first and second stacks of plates.