Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
150 words
A method of predicting the position of a register mark within an image on an elongate web relative to a reference position of the mark when the image is at a reference position the method comprising obtaining successive samples of the image and generating a corresponding binary sequence by comparing said samples with a threshold; comparing said binary sequence with a reference sequence in which said register mark is at said reference position by offsetting said two sequences by successive amounts and comparing the number of coincidences between binary values in said two sequences at each relative position; and determining the amount by which said image is offset from its said reference position by reference to the offset position of said binary sequence which has the highest number of coincidences with said reference sequence, said register mark being predicted to be offset from its reference position by a similar amount.
Claim 2
Independent Claim
150 words
A method of predicting the position of a register mark within an image on an elongate web relative to a reference position of the mark when the image is at a reference position the method comprising obtaining successive samples of the image and generating a corresponding binary sequence by comparing said samples with a threshold; comparing said binary sequence with a reference sequence in which said register mark is at said reference position by offsetting said two sequences by successive amounts and comparing the number of coincidences between binary values in said two sequences at each relative position; and determining the amount by which said image is offset from its said reference position by reference to the offset position of said binary sequence which has the highest number of coincidences with said reference sequence, said register mark being predicted to be offset from its reference position by a similar amount.
Claim 3
Dependent Claim
30 words
A method according to claim 1, wherein said samples are obtained by irradiating a portion of said image and viewing this said portion with at least one radiation sensitive detector.
Claim 4
Dependent Claim
16 words
A method according to claim 1, wherein said samples of said image are single pixel samples.
Claim 5
Dependent Claim
23 words
A method according to claim 1, wherein each binary sequence corresponds to a track extending through at least the length of the image.
Claim 6
Dependent Claim
21 words
A method according to claim 1, wherein said threshold lies halfway between the maximum and minimum values of said image samples.
Claim 7
Dependent Claim
14 words
A method according to claim 1, wherein said image is sampled every one millimeter.
Claim 8
Dependent Claim
157 words
Apparatus for predicting the position of a register mark within an image on an elongate web relative to a reference position of the mark when the image is at a reference position comprises sampling means for obtaining successive samples of the image; comparison means to compare said samples with a threshold so as to form a binary sequence; and processing means for comparing said binary sequence with a reference sequence in which said register mark is at the reference position by offsetting said two sequences by successive amounts and comparing the number of coincidences between binary values in the two sequences at each relative position, and for determining the amount by which said image is offset from its reference position by reference to the offset position of the binary sequence which has the highest number of coincidences with the reference sequence, the register mark being predicted to be offset from its reference position by a similar amount.
Claim 9
Dependent Claim
157 words
Apparatus for predicting the position of a register mark within an image on an elongate web relative to a reference position of the mark when the image is at a reference position comprises sampling means for obtaining successive samples of the image; comparison means to compare said samples with a threshold so as to form a binary sequence; and processing means for comparing said binary sequence with a reference sequence in which said register mark is at the reference position by offsetting said two sequences by successive amounts and comparing the number of coincidences between binary values in the two sequences at each relative position, and for determining the amount by which said image is offset from its reference position by reference to the offset position of the binary sequence which has the highest number of coincidences with the reference sequence, the register mark being predicted to be offset from its reference position by a similar amount.
Claim 10
Dependent Claim
27 words
Apparatus according to claim 7, wherein said sampling means comprise at least one radiation sensitive detector for viewing a portion of said web which has been irradiated.