Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
255 words
A method for making an image line with a laser beam, wherein the laser beaim is created by a laser, the intensity of the laser beam is modulated by an external modulator or by said laser, said modulated laser beam is directed onto a coding element by means of which the amplitude, phase or direction of the laser beam is transformed using an electrical control signal, the coded laser beam being directed onto a rectangular hologram at a deflection angle determined by said coding element by means of which the laser beam is transformed into focused image spots, and an image line is formed from said image spots on the image plane and wherein said laser beam is guided and transformed by optical elements, the method comprising the steps of: providing two non-mechanical laser beam deflectors, one for vertical deflection and one for horizontal deflection, to form said coding element; transforming and directing said laser beam by means of a lens and at least one grating, mirror or prism; scanning through the deflection angle in a continuous manner in the direction of the image line and in a stepwise manner in a predetermined direction that is perpendicular to the direction of the image line; and feeding the coded laser beam into said hologram which is comprised of a plurality of subholograms, each subhologram being capable of forming more than one said image spot so that different image spots are obtained by changing the incoming angle of the beam in the direction of the image line.
Claim 2
Independent Claim
255 words
A method for making an image line with a laser beam, wherein the laser beaim is created by a laser, the intensity of the laser beam is modulated by an external modulator or by said laser, said modulated laser beam is directed onto a coding element by means of which the amplitude, phase or direction of the laser beam is transformed using an electrical control signal, the coded laser beam being directed onto a rectangular hologram at a deflection angle determined by said coding element by means of which the laser beam is transformed into focused image spots, and an image line is formed from said image spots on the image plane and wherein said laser beam is guided and transformed by optical elements, the method comprising the steps of: providing two non-mechanical laser beam deflectors, one for vertical deflection and one for horizontal deflection, to form said coding element; transforming and directing said laser beam by means of a lens and at least one grating, mirror or prism; scanning through the deflection angle in a continuous manner in the direction of the image line and in a stepwise manner in a predetermined direction that is perpendicular to the direction of the image line; and feeding the coded laser beam into said hologram which is comprised of a plurality of subholograms, each subhologram being capable of forming more than one said image spot so that different image spots are obtained by changing the incoming angle of the beam in the direction of the image line.
Claim 3
Dependent Claim
18 words
A method as claimed in claim 1 wherein said two non-mechanical deflectors are acusto-optic deflectors or electro-optic deflectors.
Claim 4
Dependent Claim
73 words
A method as claimed in claim 1 further comprising the further step of: changing the direction of said laser beam using an element which includes several subelements, so designed that every subelement directs a beam which hits it at a given vertical deflection angle to a given subhologram and the beam is caused to hit the different said subholograms by changing the vertical deflection angle with a grating, a mirror or a prism.
Claim 5
Dependent Claim
77 words
A method as claimed in claim 1, comprising the further step of: measuring said deflection angles of said non-mechanical deflectors at least once during the generation of one said image line, the measurement being carried out by directing the beam by means of subholograms or parts of subholograms to photodetectors whereby said deflection angles in the direction of said image line and in the direction perpendicular thereto are measured, whereby position errors can be defined and diminished.
Claim 6
Dependent Claim
72 words
A method as claimed in claim 1, further comprising the further step of: designing said coding element, said optics and said hologram so that said image spot is, in the direction perpendicular to said image line, an image of a non-moving part of the laser beam, whereby the non moving part experiences two consecutive Fourier transformations and whereby in this direction the error of the position of said image spot is minimized.
Claim 7
Dependent Claim
86 words
A method as claimed in claim 3 or 5, wherein: said laser beam upon reaching the subholograms is collimated in a first plane in the direction of said image line and, in a second direction perpendicular thereto said laser beam is formed into a diverging cylindrical wave, and the location of a focal point of said diverging cylindrical wave is independent of said vertical deflection angle, whereby the error in the direction in which the divergence takes place becomes smaller when said laser beam is focused.