Method and apparatus for scanning a web material in the direction of its width

Claim 1

A method of scanning a web material in the direction of the width of said web material with a light beam moved by means of a polyhedral mirror with a constant speed of rotation in which said web material is spatially divided into smaller divisions in said scanning direction, said method comprising the steps of producing a series of clock pulses; detecting said light beam at a reference position from which scanning starts to actuate a counter to count up said series of clock pulses; and accessing division data stored in a storing means with counted values of said series of clock pulses by said counter to provide division signals, said division data being accessed by progressively more clock pulses as said light beam moves toward the center of said web material and by progressively fewer clock pulses as said light beam moves away from the center of said web material, whereby said web material is spatially divided into said smaller divisions in said scanning direction.

Claim 2

A method of scanning a web material in the direction of the width of said web material with a light beam moved by means of a polyhedral mirror with a constant speed of rotation in which said web material is spatially divided into smaller divisions in said scanning direction, said method comprising the steps of producing a series of clock pulses; detecting said light beam at a reference position from which scanning starts to actuate a counter to count up said series of clock pulses; and accessing division data stored in a storing means with counted values of said series of clock pulses by said counter to provide division signals, said division data being accessed by progressively more clock pulses as said light beam moves toward the center of said web material and by progressively fewer clock pulses as said light beam moves away from the center of said web material, whereby said web material is spatially divided into said smaller divisions in said scanning direction.

Claim 6

An apparatus for scanning a web material in the direction of the width of said web material with a light beam moved by means of a polyhedral mirror with a constant speed of rotation in which said web material is spatially divided into smaller divisions in said scanning direction, said aparatus comprising means for storing division data; means for producing a series of clock pulses; means disposed at a reference position from which scanning starts for detecting said light beam to provide a trigger signal; means actuated by said trigger signal for counting up said series of clock pulses to access said division data with counted values of said series of clock pulses, said division data being accessed by progressively more clock pulsles as said light beam moves toward the center of said web material and by progressively fewer clock pulses as said light beam moves away from the center of said web material, thereby providing division signals according to which said web material is spatially divided into smaller divisions in said scanning direction.

Claim 7

An apparatus for scanning a web material in the direction of the width of said web material with a light beam moved by means of a polyhedral mirror with a constant speed of rotation in which said web material is spatially divided into smaller divisions in said scanning direction, said aparatus comprising means for storing division data; means for producing a series of clock pulses; means disposed at a reference position from which scanning starts for detecting said light beam to provide a trigger signal; means actuated by said trigger signal for counting up said series of clock pulses to access said division data with counted values of said series of clock pulses, said division data being accessed by progressively more clock pulsles as said light beam moves toward the center of said web material and by progressively fewer clock pulses as said light beam moves away from the center of said web material, thereby providing division signals according to which said web material is spatially divided into smaller divisions in said scanning direction.