Image registration in a multiple magnification photocopying system

Claim 2

Exposure apparatus for regulating borders on copies produced by a photocopying machine capable of generating a light image for exposing a photosensitive target comprising a single multiple focus lens system for fixed overall conjugate projections positioned relative to said light image and target such that the light image is in the object plane of the lens system and the target is in the image plane of the lens system, a photosensitive target including a photosensitive member in web form with a plane surface thereof supported for movement through the image plane of said lens system, means for generating said light image including flash lamp means positioned to illuminate a platen for supporting an opaque document wherein said lamp illuminates said platen for a period of time sufficiently short to permit the target to be considered substantially stationary during exposure, electrical means for controlling the instant in time at which said flash lamp illuminates the platen for regulating the dimensions of borders associated with the copies produced by the machine, and displacement means for supporting said lens system and for displacing the lens system parallel to the optical axis to obtain different size focused projections of said light images on the target and for displacing the lens system perpendiculAr to the optical axis to regulate the dimensions of borders associated with copies produced by the machine.

Claim 3

The apparatus of claim 1 further including registration means positioned in said image plane for aligning one edge of said light image relative to said target.

Claim 4

The apparatus of claim 1 wherein said lens system includes an add lens system comprising main lens elements and at least one add lens element.

Claim 5

The apparatus of claim 3 further including at least one plane mirror for folding the optical path of the lens system without changing the overall conjugate.

Claim 6

The apparatus of claim 4 including two plane mirrors for folding the optical path of said lens system without changing the overall conjugate.

Claim 7

The apparatus of claim 1 wherein said photosensitive target includes an electrically photosensitive member on which a latent electrostatic image is formed upon exposure of the target to the light image.

Claim 8

The apparatus of claim 6 wherein said photocopying machine is a xerographic machine including means for developing said latent electrostatic image forming a toner image, means for transferring said toner image to a transfer member and means for fixing said toner image permanently to the transfer member.

Claim 9

The apparatus of claim 7 wherein said photosensitive target includes reusable surface areas and said xerographic machine further includes means for cleaning said target after the toner image is transferred therefrom.

Claim 10

The apparatus of claim 1 wherein said displacement means includes means for positioning said lens system to at least points X and Z where X is a first lens system position for projecting a focused image of a first light image to the target and Z is a second lens system position for projecting a focused image of a larger light image to the target where Z is defined by the intersection of extreme rays projected from the larger light image to the boundaries of the target.

Claim 11

The apparatus of claim 1 wherein said displacement means includes means for positioning said lens system to at least points X and M where X is a first lens system position for projecting a focused image of a first light image to the target and M is a second lens system position for projecting a focused image of a larger light image to the target where M is defined by the intersection of a line drawn from the center of the larger light image to the center of the target and a line normal to the optical axis.

Claim 12

The apparatus of claim 9 wherein said displacement means includes means coupled to said lens system and slidably coupled to at least one linear rail oriented substantially parallel to a line drawn between points X and Z.

Claim 13

The apparatus of claim 10 wherein said displacement means includes means coupled to said lens system and slidably coupled to at least one linear rail oriented substantially parallel to a line drawn between points X and M.

Claim 14

The apparatus of claim 12 wherein said displacement means includes means to position said lens system at point X and a plurality of point M''s with said rail oriented parallel to the line drawn between point X and the M point furthest from the X point.

Claim 15

Exposure apparatus for regulating borders on copies produced by a photocopying machine comprising a photosensitive target including a plane surface image forming area capable of having a latent electrostatic image created thereon upon exposure to a light image, means for generating in a fixedly located plane light images of more than one size with one edge of all sizes of light images being aligned relative to one edge of the image forming area of the target for regulating the borders on two opposite sides of said copies, a multiple focus lens system including means for changing focal length to project light images of different size to the target without any projected image substantially exceeding the dimensions of the image forming area upon moving the lens system parallel to the optical axis but without changing the length of the overall conjugate and displacement means for moving said lens system along a linear path angled to the optical axis defined by points X and M where X is a lens system position for projecting a light image of first size to the target with the optical axis coincident with a line between the centers of the light image and target and where M is the intersection of a line between the centers of the target and a light image of second size and a normal from point Y on the X position optical axis where Y is the lens system position for projecting a light image of a second size to the target said M lens system position causing the production of copies having borders differing from those resulting from the X lens system position but which are nonetheless symmetrical on opposite sides of the copies.

Claim 16

Exposure apparatus for regulating borders on copies produced by a photocopying machine comprising a photosensitive target including a plane surface image forming area capable of having a latent electrostatic image created thereon upon exposure to a light image, means for generating in a fixedly located plane light images of more than one size with one edge of all sizes of light images being aligned relative to one edge of the image forming area of the target for regulating the borders on two opposite sides of said copies, a multiple focus lens system including means for changing focal length to project light images of different size to the target without any projected image substantially exceeding the dimensions of the image forming area upon moving the lens system parallel to the optical axis but without changing the length of the overall conjugate and displacement means for moving said lens system along a linear path angled to the optical axis defined by points X and M where X is a lens system position for projecting a light image of first size to the target with the optical axis coincident with a line between the centers of the light image and target and where M is the intersection of a line between the centers of the target and a light image of second size and a normal from point Y on the X position optical axis where Y is the lens system position for projecting a light image of a second size to the target said M lens system position causing the production of copies having borders differing from those resulting from the X lens system position but which are nonetheless symmetrical on opposite sides of the copies.

Claim 17

Exposure apparatus for regulating borders on copies produced by a photocopying machine comprising a photosensitive target including a plane surface image forming area capable of having a latent electrstatic image formed thereon upon exposure to a light image, means for generating in a fixedly located plane light images of at least three sizes being equal to or greater than the image forming area of the target with one edge of all sizes of light images being aligned relative to one edge of the image forming area on the target for regulating the borders on opposite sides of said copies, a multiple focus lens system including means for changing the focal length for the projection of at least said three light images to the target without any projected image substantially exceeding the dimensions of the image forming area upon moving the lens system along the optical axis but without changing the length of the overall conjugate and displacement means for moving said lens system to at least three positions along a linear path at an angle to the optical axis defined by points X and M where X is a lens system position for projecting a light image of first size to the target with the optical axis coincident with a line between the centers of the light image and target and where M is the intersection of a line between the centers of the target and a light image of a second larger size and a normal from point Y on the X position optical axis where Y is the lens system position for projecting said light image of second size to the target, said third lens system position on said linear path not including the point of intersection between the line between the centers of the target and a light image of third size and a normal from point Y on the X position optical axis where Y is the lens system position for projecting said light image of said third size to the target.

Claim 18

Exposure apparatus for regulating borders on copies produced by a photocopying machine comprising a photosensitive target including a plane surface image forming area capable of having a latent electrstatic image formed thereon upon exposure to a light image, means for generating in a fixedly located plane light images of at least three sizes being equal to or greater than the image forming area of the target with one edge of all sizes of light images being aligned relative to one edge of the image forming area on the target for regulating the borders on opposite sides of said copies, a multiple focus lens system including means for changing the focal length for the projection of at least said three light images to the target without any projected image substantially exceeding the dimensions of the image forming area upon moving the lens system along the optical axis but without changing the length of the overall conjugate and displacement means for moving said lens system to at least three positions along a linear path at an angle to the optical axis defined by points X and M where X is a lens system position for projecting a light image of first size to the target with the optical axis coincident with a line between the centers of the light image and target and where M is the intersection of a line between the centers of the target and a light image of a second larger size and a normal from point Y on the X position optical axis where Y is the lens system position for projecting said light image of second size to the target, said third lens system position on said linear path not including the point of intersection between the line between the centers of the target and a light image of third size and a normal from point Y on the X position optical axis where Y is the lens system position for projecting said light image of said third size to the target.

Claim 19

The apparatus of claim 15 wherein said target is supported for movement through the image plane of said lens system, said means for generating light images includes flash lamp means for illuminating a platen for supporting opaque documents, said period of illumination being a time sufficiently short compared to the rate of travel of the target to enable the target to be considered stationary during the exposure and further including electrical circuit means for controlling the instant in time the illumination occurs in order to regulate the borders associated with copies produced when said lens system is positioned at said third lens system position.

Claim 20

An electrostatic reproduction maching having an illumination means wherein copies of an original document are produced by flashing the illumination means to produce a flashed light image onto a photoreceptor and effect an electrostatic latent image thereon disposed in an image plane, including, lens means for projecting a flashed light image of said original document onto said photoreceptor, means for producing a flash exposure of the document in timed relation with the movement of the photoreceptor, and flash control Means coupled to said producing means for effecting flash energizing of the illumination means to generate a flashed light image, said flash control means being responsive to a selectable means for varying the application of said flash energization of said illumination means for a predetermined time duration thereby shifting the formation of an electrostatic latent image on the photoreceptor relative to its machine-timed position without the varying of flash exposure.

Claim 21

An electrostatic reproduction maching having an illumination means wherein copies of an original document are produced by flashing the illumination means to produce a flashed light image onto a photoreceptor and effect an electrostatic latent image thereon disposed in an image plane, including, lens means for projecting a flashed light image of said original document onto said photoreceptor, means for producing a flash exposure of the document in timed relation with the movement of the photoreceptor, and flash control Means coupled to said producing means for effecting flash energizing of the illumination means to generate a flashed light image, said flash control means being responsive to a selectable means for varying the application of said flash energization of said illumination means for a predetermined time duration thereby shifting the formation of an electrostatic latent image on the photoreceptor relative to its machine-timed position without the varying of flash exposure.

Claim 22

THe machine of claim 17 wherein said varying of the application of flash energization is such as to delay flash exposure.

Claim 23

An electrostatic reproduction machine having an illumination means for producing electrostatic latent images upon a moving photoreceptor web thereon; developing apparatus for developing the latent images; sheet feed means for feeding sheets seriatim to the developed images; transfer means for effecting the transfer of developed images to sheets; and machine control means for (a) flashing the illumination means, (b) for activating the sheet feed means and (c) the transfer means in timed relation to the moving photoreceptor web, the improvement including flash control means coupled to the machine control means being responsive to a selectable means for delaying the application of the flashing of the illumination means while maintaining the timed relationship for the activation of the sheet feed means.

Claim 24

An electrostatic reproduction machine having an illumination means for producing electrostatic latent images upon a moving photoreceptor web thereon; developing apparatus for developing the latent images; sheet feed means for feeding sheets seriatim to the developed images; transfer means for effecting the transfer of developed images to sheets; and machine control means for (a) flashing the illumination means, (b) for activating the sheet feed means and (c) the transfer means in timed relation to the moving photoreceptor web, the improvement including flash control means coupled to the machine control means being responsive to a selectable means for delaying the application of the flashing of the illumination means while maintaining the timed relationship for the activation of the sheet feed means.