Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
45 words
An imaging system comprising means for compensating vignetting in an image supplied by an image generation means, characterised in that said imaging system comprises pixel-value amplification means for amplifying pixel-values of the image in relation to a decrease in brightness due to an image perturbation.
Claim 2
Dependent Claim
32 words
An imaging system as claimed in Claim 1, further characterised in that said amplification means are arranged as multiplication means for computing corrected pixel-values by multiplying pixel-values by electronically provided correction factors.
Claim 3
Dependent Claim
23 words
An imaging system as claimed in Claim 2, further characterised in that the imaging system comprises electronical memory means for storing correction factors.
Claim 4
Dependent Claim
77 words
An imaging system as claimed in any one of Claims 2 or 3, wherein said multiplication means is arranged as analog multiplication means, said memory means is arranged for digitally storing correction factors and the imaging system comprises a digital-to-analog converter arranged for converting digital correction factors into analog correction factors, further characterised in that the imaging system comprises a low-pass filter for smoothing step-like variations between analog correction factors pertaining to successive pixels in the image.
Claim 5
Dependent Claim
78 words
An imaging system as claimed in any one of Claims 2 or 3, wherein said multiplication means is arranged as digital multiplication means, said memory means is arranged for digitally storing correction factors and the imaging system comprises a digital-to-analog converter arranged for converting digital corrected pixel-values into analog corrected pixel-values, further characterised in that the imaging system comprises a low-pass filter arranged for smoothing step-like variations between analog corrected pixel-values pertaining to successive pixels of the image.
Claim 6
Dependent Claim
33 words
An imaging system as claimed in any one of Claims 3 to 5, further characterised in that said memory means is arranged for storing correction factors for groups of pixels of the image.
Claim 7
Dependent Claim
28 words
An imaging system as claimed in Claim 6, further characterised in that said groups are constituted by pixels having a fixed distance from a centre of the image.
Claim 8
Dependent Claim
72 words
An imaging system as claimed in any one of Claims 3 to 5, further characterised in that said memory means is arranged for storing first correction factors for pixels on a predetermined line in the image and for storing second correction factors for lines in the image parallel to said predetermined line and in that said multiplication means is arranged for multiplying pixel-values by first correction factors and by second correction factors.
Claim 9
Dependent Claim
81 words
An imaging system as claimed in any one of Claims 3 to 8, further characterised in that said memory means is arranged for storing a plurality of sets of correction factors, each of said sets pertaining to a parameter setting of the imaging system and/or of the image generating means, and in that the imaging system comprises signal production means for producing discrimination signals, each of said discrimination signals pertaining to a parameter setting for selecting a set of correction factors.
Claim 10
Dependent Claim
81 words
An imaging system as claimed in any one of Claims 3-9, further characterised in that said memory means is arranged for storing numerical elements and further comprises conversion means for converting positions of pixels in the image into distances between relevant pixels and one point in the image, and calculation means for computing correction factors as a value of predetermined mathematical functions in said distances, said predetermined mathematical functions being further determined by numerical element being stored in said memory means.
Claim 11
Dependent Claim
26 words
An imaging system as claimed in Claim 10, further characterised in that said predetermined mathematical functions are polynomial functions and said numerical elements are polynomial coefficients.
Claim 12
Dependent Claim
72 words
An imaging system as claimed in any one of Claims 10 or 11, further characterised in that said memory means is arranged for storing a plurality of sets of numerical elements, each of said sets pertaining to a parameter setting of the imaging system, the imaging system comprising signal production means for producing discrimination signals, each of said discrimination signals pertaining to a parameter setting for selecting a set of numerical elements.
Claim 13
Dependent Claim
98 words
An imaging system as claimed in Claim 1, also comprising beam splitting means for splitting an image carrying radiation beam into a plurality of sub-image carrying radiation beams, and comprising a multitude of image sensors for recording each of the sub-images, and comprising recombination means for recombining sub-images into a recombined image, further characterised in that the imaging system comprises memory means for storing a plurality sets of correction factors and in that said amplification means are arranged as multiplication means for computing corrected pixel-values by multiplying pixel-values by correction factors selected from said sets of correction factors.
Claim 14
Dependent Claim
77 words
An imaging system as claimed in Claim 13, further characterised in that a said beam splitting means is constituted by a single beam-splitter for splitting an image into two sub-images, further characterised in that said memory means is arranged for storing a first set of correction factors for compensating vignetting in first direction in the recombined image and for storing a second set of correction factors for compensating vignetting in a second direction in the recombined image.
Claim 15
Dependent Claim
17 words
An x-ray examination apparatus comprising an imaging system in accordance with any one of the preceding Claims.