US3920326A - Electrophotographic copying apparatus - Google Patents

Electrophotographic copying apparatus Download PDF

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Publication number
US3920326A
US3920326A US524895A US52489574A US3920326A US 3920326 A US3920326 A US 3920326A US 524895 A US524895 A US 524895A US 52489574 A US52489574 A US 52489574A US 3920326 A US3920326 A US 3920326A
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Prior art keywords
mirror
illuminating
scanning
displacement
original image
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Expired - Lifetime
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US524895A
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English (en)
Inventor
Heimo Hirth
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Hoechst AG
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Hoechst AG
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    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/04—Apparatus for electrographic processes using a charge pattern for exposing, i.e. imagewise exposure by optically projecting the original image on a photoconductive recording material
    • G03G15/0409—Details of projection optics
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B27/00—Photographic printing apparatus
    • G03B27/32—Projection printing apparatus, e.g. enlarger, copying camera
    • G03B27/52—Details
    • G03B27/522—Projection optics
    • G03B27/525—Projection optics for slit exposure
    • G03B27/526—Projection optics for slit exposure in which the projection optics move

Definitions

  • an electrophotographic copying apparatus [2] 1 App]; 524 comprising an improved optical system for reproduc- 5 ing an original image on a photoconductor, comprisg ing a stationary lens, a linearly displaceable reflecting [30]
  • Foreign Application Prlority Data arrangement comprising at least two scanning reflec- Nov. 19, 1973 Germany 2357582 tors j g each other in fixed angular relationship and at least one illuminating reflector rigidly con- [52] us. Cl. 355/8; 355/66 ect t he ca ng efl c o a means for i [51] Int. Cl.
  • This invention relates to an felectrophotographic copying apparatus, and more especially to such an apparatus in which an original disposed on a planar fixed supporting surface is reproduced, strip by strip, on a moving charged photoconductive surface and which comprises moving optical components to assure that the image of the original is projected onto the moving photoconductor.
  • a stationary original is reproduced on a stationary photoconductor.
  • exposure and reproduction do not offer any particular problems.
  • Such devices are not suitable, however, for
  • a further system comprises a moving support plate for the original which is moved in synchronism with the photoconductor.
  • the original is normally scanned strip-wise and reproduced on the photoconductorthrough an appropriate slot.
  • Such systems have the serious drawback that the original must be displaced in the apparatus. This involves the risk of damaging the original, and in most cases an apparatus of this type can not be used for copying from books. Further, it is impossible with such devices to reproduce cut-outs from larger originals.
  • a stationary original is reproduced on a moving photoconductor.
  • One way of doing this is to make the exposure time so short that the lack of sharpness caused by the movement of the conductor is negligible. In these cases, a flash exposure is used.
  • the difficulty with this type of apparatus is that the entire original must be reproduced on a planar photoconductor surface of corresponding size. For this purpose, the photoconductor web must be capable of rotation, which makes the apparatus relatively expensive.
  • a further class of reproduction system in which a stationary original is reproduced on a moving photoconductor may be characterized by the use of moving optical compensating elements.
  • Two systems of this category have become particularly well known.
  • the system described in German Offenlegungsschrift No. 1,497,089 uses a swiveling mirror which is oscillated for scanning of the original.
  • the original is placed on a cylindrically curved surface, with the axis of the cylinder and the swivel axis of the mirror coinciding.
  • the swivel movement of the mirror is adjusted so that the strip of originalscanned is reproduced on the moving photoconductor as a stationary image.
  • the main drawback of this apparatus is that the surface on which the original is placed must be curved. This is particularly undesirable because it renders it impossible to reproduce double pages of books on one and the same copy sheet.
  • a movable mirror scanningoptical system is used.
  • a system of this type is described, for example, in German Patent No. 1,215,503.
  • This system comprises two groups of mirrors moved in the 2 same direction.
  • the first group of mirrors comprises a scanning mirror which forms an angle of inclination of 45 with the supporting surface for the original and is moved along the supportingv surface at exactly the speed used for scanning.
  • the second group of mirrors which comprises two mirrors, the light beam already deflected by the first mirror is further deflected by 180.
  • This second group of mirrors is moved at half the speed of scanning.
  • the result achieved in this man'- ner is that the optical distance from each scanned area on the original to the lens or to the photoconductor remains constant.
  • This apparatus has the serious drawback that two groups of mirrors must be providedv which must be moved in opposite directions. Despite the fact that the original is scanned at an angle of 90 and that the original is disposed on a planar surface, this drawback causes difficulties because the two groups of mirrors must be controlled by extremely accurate mechanical means, and this requires an extremely high mechanical expenditure.
  • US Pat. No. 3,062,094 discloses a further apparatus comprisin a movable mirror system.
  • an optical system which is spaced respectively from the exposure slot of the photoconductor and from the original a distance corresponding in each case to twice the focal distance, is displaced along a straight line at half the speed of scanning.
  • This principle also involves some very annoying disadvantages.
  • the space required is extremely large, because the distance between the moving lens and the stationary original is very long and must be provided within the apparatus.
  • this space may be arranged so that it is no longer perpendicular; however, the large space required is still rather troublesome.
  • the Japanese Utility Model discloses a tubular light which is moved past the original at scanning speed, i.e., twice the speed of the mirrors. This requires a considerable equipment expenditure and involves the drawback that the lightsource must also be moved.
  • 'A further object of the invention is to provide an electrophotographic copying apparatus having an improved optical system for, reproducing an original image onto a photoconductor.
  • Still another object of the invention is to provide an improved optical system for use in an electrophotographic copying apparatus.
  • an electrophotographic copying apparatus which is characterized in that it comprises a combination of the following features:
  • An electrophotographic copying apparatus comprising (A) a photoconductive surface; (B) means for rotating the photoconductive surface, preferably about a closed path; (C) means for uniformly charging the photoconductive surface; (D) a slotted diaphragm arranged in front of the photoconductor and transversely to its direction of movement, through which the photoconductor surface is expo'sed;(E) a planar transparent support surface for an originalimage to be copied, either an original object or the virtual image of an original object; (F) optical means for reproducing the original image upon said photoconductive surface, this optical means comprising "(i) a first stationary lens for directing a scanned image from said original" image to said photoconductive surface, (ii) a reflecting arrangement adaptedfor displacement along a straight line,
  • this arrangement comprising (a)' at least two scanning reflecting elements, preferably mirrors, rigidly joining with one another in fixed angular relationship, whereby, when the original image is scanned, a moving visual image is'produced behind the scanning reflecting element from the'view'point of said first stationary lens, and (b) at least'one illuminating reflecting element, preferably a mirror, rigidly connected to the scanning reflecting elements and arranged at such an angle to the original image supporting surface that a normal to the illuminating reflecting element, a normal to the original image, and'the straight line of displacement lie in a single plane, this straight line of displacement being defined such that the moving virtual image is displaced in a direction lying in the aforesaid plane when the reflecting arrangement is displaced along the line; a-
  • the problem which is actually solved by the present invention is the illumination of the original.
  • the copying speed of an electrophotographic apparatus depends, to a certain degree, on the intensity of illuminascanned original orto the scanned virtual image of the original.
  • Thenormal to the scanned original to the illuproduces an exposure which is absolutely homogeneousg except for variations in thebrightness of the lamp.
  • L This results from the fact that the distancebetween the illuminated strip of the original and the light source is' always constant, because the illuminating mirror follows the movementofthe scanning mirrorsand the image of the light source on the original moves at exactly the same speed as the principal scanning point.
  • the fixed mirror arrangement consistingof two scanning mirrors and at least one illuminating mirror is displaced along the line at such a speed that the component of speed parallel to the original or to its stationary virtual image corresponds exactly to half the circumferential speed of the photoconductor.
  • the construction of thecopying apparatus. according to the present invention is particularly simple and compact when the mirror arrangement comprises two scanning mirrors, which form a right angle between them and which are each inclined at an angle of 45 with respect to the transparent support plate for the original,
  • At least one illuminatingmirror is rigidly connected with side, the angled scanning mirror facing the support plate projects somewhat beyond the original tobe scanned. In this manner, the whole original may be scanned without any loss of information.
  • a angle mirror is insensitive to distortions about the junction of the mirrors.
  • the illuminating mirror is arranged and/or behind the scanning mirror assembly in the direction of displacement, at a distance which at least slightly exceeds half the scanning length of the original.
  • An essential feature of the above defined electrophotographic copying apparatus is that only one mirror arrangement comprising fixedly connected scanning and illuminating mirrors is provided in the apparatus.
  • This mirror arrangement has the following functions:
  • a displaceable mirror arrangement is used, the direction of displacement being so selected that the virtual image of the original formed-in the scanning mirrors is displaced only within this virtual imaging plane, but does not leave this plane.
  • the virtual imaging plane is, so 'to speak, stationary. In principle, two mirrors are sufficient'for thisr'rianner of reproduction, but at least two mirrors are required.
  • the individual mirrors of the mirror arrangement may extend in the form of a trapezoid in the direction of the ray path, i.e., from the stationary support plate to the lens, with the angle of convergence corresponding approximately to the aperture angle of the lens utilized. In this manner, the mirror surfaces may be kept rather small, and accordingly, this construction is preferred.
  • the resulting oblique illumination of the original is very desirable, because it has been found that, in the case of a perpendicular scanning of originals, an oblique illumination at an angle of about 45 leads to optimum contrasts.
  • One of the reasons for this phenomenon is that reflections from smooth, black printed areas do not reach the photoconductor.
  • a copying apparatus of the above described type which comprises one or more of the following features: (a) the apparatus has a single electromotor for driving the photoconductor and driving the mirror arrangement, and the two drives are mechanically interconnected with each other; (b) a return spring is provided for retracting the mirror arrangement, as well as a clutch between the drive for the mirror arrangement and the drive of the photoconductor, said clutch being released as soon as the mirror arrangement has passed the end of the scanning path; On both sides of the displaceable mirror arrangement, guide rails are provided which extend in the direction of the line of displacement; (d) the drive for the mirror arrangement and the drive for the photoconductor are connected by an nonextendible rope or band which is guided in a circular disk and is capable of being wound off of and onto the disk.
  • the circular disk is arranged coaxially with the roller or drum carrying the photoconductor, and one end of the rope or band is finnly attached to the circular disk and the other end is firmly attached to the displaceable mirror arrangement.
  • a clutch is provided between the circular disk and the roller or drum.
  • FIGS. 1a and 1b illustrate the operation of the apparatus according to the invention by way of a particularly lucid, preferred embodiment of the inventive apparatus.
  • Pulleys 17 and 18 are arranged to both sides of the photoconductor drum and coaxially with it.
  • the diameter of these pulleys is one half that of the photoconductor drum.
  • the two pulleys 17 and 18 may be selectively connected with and released from the drum by means of a clutch diagrammatically shown by pins 19 and 20, which may be operated magnetically, for instance.
  • Steel bands 21 and 22 are fastened to the pulleys l7 and 18, respectively.
  • the other ends of the steel bands are fastened to the carriage 23 which is displaceable on the rails 5 and In FIGS. la and lb, this carriage is diagrammatically shown as a frame formed by four rods 24, 25, 26, and 27, with the frame being suspended from four wheels 28, 29, 30, and 31.
  • the double mirror 3,4 is also attached to this frame.
  • the steel band 22 must be deflected by a fixed roller 32. Further, the carriage 23 is connected with a return spring 33 which returns it to the dotted initial position when the pins 19 and 20 are released.
  • the area 10 at the extreme lefthand side of the original 1 is reproduced through the slot 11 onto a photoconductor 13 which may be rotated by means of a drum 12.
  • This reproduction is done with the aid of mirrors 7 and 8 fixedly mounted in the apparatus and a likewise fixedly mounted lens 9.
  • the drum 12 carrying the photoconductor 13 is rotated such that the photoconductor 13 moves in the direction of the arrow at a speed v. In this manner, the carriage carrying the mirrors is displaced parallel to the support plate 2 at a speed v/2.
  • the position shown by the solid lines in FIG. la is the end position of the mirror arrangement.
  • the initial position of the mirrors 3 and 4 is shown by dotted lines. In this initial position the area at the extreme right of the original 1 is reproduced through the slot 11 onto the photoconductor 13. It is apparent that the scanning area moves along the original at a speed v when the mirrors travel at a speed v/2. Furthermore, it can be seen that the opticaldistance from the scanned area to the photoconductor is always constant.
  • the photoconductor 13 Prior to exposure through the slot 11, the photoconductor 13 .is charged in the normal manner by means of a corona 14, and the latent electrostatic charge pattern formed on the photoconductor by exposure is developed in a developing station 15. In a transfer station 16, the developed image is transferred onto a web of paper 47. In principle, it is also possible to use a charge-transfer process or to employ zinc oxide paper, in which case the apparatus must be constructed so that nonreversed copies are produced by an appropriate number of reversals.
  • the mirrors 3 and 4 may be of trapezoidal shape, as indicated in the plan view shown in FIG. 1b.
  • the shape of the trapezoid is determined by the aperture angle of lens 9 which is utilized.
  • the trapezoidal mirrors 3 and 4 converge toward the lens 9 at about the same angle as is determined by the lens and the width of the original.
  • the apparatus according to the present invention is equipped with a special illuminating system.
  • An illuminating mirror 38 is firmly connected with mirrors 3 and 4. For example, it may also be mounted on the carriage 23.
  • the three mirrors 3, 4, and 38 are firmly combinedto form a single mirror arrangement which may be displaced along the rails extending parallel to the support plate 2.
  • the light rays of a light source 34 preferably an elongated luminous surface, thelongitudinal direction of which extends normal to the plane of the drawing in FIG.
  • the longitudinal and transverse measurements of which correspond to the proportions of the slot 11 correspond to the proportions of the slot 11 (taking into account, of course, that the light impinges obliquely) are directed through the support plate 2 onto the original 1 by means of lens 35, a fixed return-deflecting mirror 36, and an illuminating mirror 38.
  • the illuminating mirror 38 is arranged at right angles to the support plate 2, and the path of the illuminating rays is selected so that, at the beginning of the scanning process (i.e., in the position shown by the dotted lines in FIG. 1a), the elongated luminous surface 34 illuminates the original exactly in the area corresponding to the image producedby the lens 9 and'the mirrors 8, 7, 4, and 3 on the strip of photoconductor limited by the slot 11.
  • FIG. la this is diagrammatically indicated by the intersection 37 of the main scanning direction and the main illuminating direction.
  • the main illuminating point 37 By arranging the mirror 38 vertically to the support plate 2, it is ensured that, by a displacement of the mirror38 to the left-hand'sideat a speed v/2, the main illuminating point 37 likewise travels to the left along the surface of the support plate 2, but at a speed v. The main scanning point also travels to the left at the same speed. In this manner, care is taken that the scanned area, but only the scanned area, is always illuminated. The fact that the illumination is effected at an angle which differs from 90 is highly desirable, because it has been found that by copying substantially outside of the conditions of reflection, copies are produced having a contrast which is much better than when working under conditions of reflection.
  • the dimensions of the image of the lamp 34 may be changed by means of a cylindrical lens. It is also possible to provide an additional illumination device comprising a second light source 34a a third lens 35a, a second retum-deflection mirror 36a, and a second illuminating mirror 38a.
  • the virtual image plane 342 formed by the two mirrors 3 and 4 is shown as a dotted line.
  • the direction in which the mirrors are displaced coincides with the bisector 340 of the angle formed between the plane 2 and the virtual plane 342.
  • the virtual plane 32 of the surface 2 reflected by the of the mirror;3 .being the plane of symmetry of the double angle 2a.
  • the second reflection of the plane 2 by the mirror 4 produces the virtual image 3420f the plane.
  • This plane is found by reflecting the angle B mirrors 3 and 4 are provided by means of which the formed between the virtual plane 32 and the plane of the mirror 4 on the other side of the latter plane. Because it is a precondition that the original is to be scanned on the plane 2 at an angle of the direction 90 of the optical axis of the lens 9 is found by drawing a perpendicular line on the virtual image 342 of the plane 2. In the drawing, this is diagrammatically indicated by the right angle 341 in FIG. 2. This right angle corresponds to the right angle 23 at which the plane 2 is scanned.
  • the position of this straight line is defined in that the virtual image 342 of the plane 2 produced by the two mirrors 3 and 4 is displaced only'within itself, by the displacement of the mirrors 3 and 4 along the line of displacement 340, but is not displaced in the perpendicular direction, i.e. in the direction of the optical axis 90. It is assumed that first the position of thernirror 4 is fixed and that the mirror 3 is moved in the direction of its normal by half the length of the arrow 31. Accordingly, the virtual image 32 is also displaced in the direction of the arrow 31. Because of the second reflection by the mirror 4, the virtual image 342'is displaced by a distance which corresponds to arrow 41.
  • point I of the virtual image 342 is displaced to a position I. Since it is conditioned that a displacement of the virtual image 342 shall take place within its plane only, point I must be moved from its position by an appropriate displacement and assume a position within the plane of the virtual image 342, as indicated by the position 1''. Thus, in order to displace the virtual image 342 without the application of a normal component, i.e. within the virtual image plane, a further displacing component 42 must be provided, which may be achieved by the mirror 4 which initially had been static.
  • the point I in the vir tual plane 342 is displaced to the position I and from there returned to the plane of the virtual image 342 to take position I".
  • the direction of this displacing component 42 is determined by the fact that invariably it is only a displacement vertically to the plane of a mirror which causes a displacement of the virtual image.
  • the component 42 must beat right angles to the plane of the mirror 4, as indicated by the angle 43.
  • the direction of the line of displacement 340 is defined in that the component of displacement vertically to the plane of the mirror 3 must have the length of the arrow 31, and the component of displacement vertically to the plane of the mirror 4 must have'the length of the arrow 42.
  • the direction of the'line of displacement 340 is obtained in that the 'vectors of displacement issuing, for example, from the intersection of mirrors 3 and 4 are marked down, and that at their ends perpendicular lines to the vectors are drawn, and the intersection of these normals is then connected with the intersection 9 of the two mirrors 3 and 4.
  • the mirrors 3 and 4 are displaced by the length of the vector 34 thus obtained, the mirror 3 is displaced in a vertical direction j by the length of the vector 31 and, at the same time, the mirror 4 is displaced in the vertical direction by the length of the vector 42.
  • the direction of the line of displacement is defined as the bisector of the angle formed by the plane of the support plate and the virtual image of the image on the support plate formed by the two mirrors. This angle between the two planes is independent of a rotation of the double mirror and is determined solely by the angle formed by the two mirrors.
  • a plane supporting surface for the original is provided.
  • the displaceable mirror arrangement is moved at half the speed of the photoconductor surface.
  • the mirror arrangement is only displaced through half the length of the original to be scanned.
  • the height of the apparatus may be maintained relatively small.
  • Illumination is by a stationary light source, without any additional moving elements.
  • the mirror arrangement is not susceptible to a rotary motion about an axis parallel to the slot at the photoconductor. i
  • An electrophotographic copying apparatus comprising:
  • D a slotted diaphragm arranged in front of the photoconductor and transversely to its direction of movement, through which the photoconductor surface is exposed;
  • optical means for reproducing said original image upon said photoconductive surface, said optical means comprising i. a first stationary lens for directing a scanned image from said original image to said photoconductive surface;
  • a reflecting arrangement adapted for displacement along a straight line, said arrangement comprising a. at least two scanning reflecting elements rigidly joining with one another in fixed angular relationship, whereby, when said original image is scanned,
  • At least one illuminating reflecting element rigidly connected to said scanning reflecting elements and arranged at such an angle to said original image supporting surface that a normal to said illuminating reflecting element, a normal to said original image, and said straight line of displacement lie in a single plane, said straight line of displacement being defined such that said moving virtual image is displaced in a direction also lying in said plane when said reflecting arrangement is displaced along said line;
  • G a stationary light source
  • a second stationary lens for receiving a light beam from said light source and projecting said light into said illuminating reflecting element and from said illuminating reflecting element onto said original image, thereby illuminating the original image
  • said reflecting element is a mirror arrangement comprising as said scanning reflecting elements at least two scanning mirrors and as said illuminating reflective element at least one illuminating mirror.
  • each of said scanning mirrors has a trapezoidal shape converging in the direction of light travel from said support surface to said first stationary lens.
  • optical system further comprises at least one further stationary mirror surface optically cooperating with said first stationary lens.
  • said illuminating mirror is arranged behind said scanning mirrors in said direction nated at an angle between about 30 and 60.
  • the electrophotographic copying apparatus as defined by claim 1, further comprising releasable clutch means for rendering said displacing means selec- 18.
  • said returning means comprises a spring member adapted to be tensioned during said scanning and relaxed to cause said return of said mirror arrangement.
  • said means for displacing said mirror arrangement comprise at least one guide rail arranged on each side of said mirror arrangement in the direction of said line of displacement and a carriage for said arrangement adapted to be guided upon said rails.
  • At least one illuminating reflecting element rigidly connected to said scanning reflective elements and arranged at such an angle to said original image supporting surface that a nonnal to said illuminating reflecting element, a normal to said original image and said straight line of displacement lie in a single plane, said straight line of displacement being defined such that said moving virtual image is displaced in a direction also lying in said plane when said reflecting arrangement is displaced along said line;
  • said reflecting element is a-mirror arrangement comprising as said scanning reflecting elements at least two scanning mirrors and as said illuminating reflective ⁇ element at least one illuminating mirror.
  • optical system as defined by claim 23, comprising two scanning mirrors and wherein the line of juncture formed by said joined scanning mirrors extends parallel to the plane of said support surface, and wherein said line of displacement bisects the angle formed between said support surface and said moving virtual image.
  • said illuminating mirror is inclined with respect to said support surface at an angle whereby said illuminating light beam for the original image travels over said original image at the same speed as said original image is scanned by said scanning mirrors.
  • said illuminating mirror is arranged in spaced relationship to said scanning mirrors along the direction of said displacement line for said mirror arrangement and normal to said line of displacement and wherein said illuminating mirror is at a right angle to said support surface.

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  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • General Physics & Mathematics (AREA)
  • Optical Systems Of Projection Type Copiers (AREA)
  • Exposure Or Original Feeding In Electrophotography (AREA)
US524895A 1973-11-19 1974-11-18 Electrophotographic copying apparatus Expired - Lifetime US3920326A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE2357582A DE2357582C2 (de) 1973-11-19 1973-11-19 Elektrofotografisches Kopiergerät mit einem auf einem Wagen hin- und herbewegbaren optischen Abtastsystem

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US3920326A true US3920326A (en) 1975-11-18

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US524895A Expired - Lifetime US3920326A (en) 1973-11-19 1974-11-18 Electrophotographic copying apparatus

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US (1) US3920326A (de)
JP (1) JPS5710425B2 (de)
DE (1) DE2357582C2 (de)
FR (1) FR2251851B1 (de)
GB (1) GB1482478A (de)
NL (1) NL7414603A (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4189763A (en) * 1977-01-25 1980-02-19 Ricoh Company Ltd. Document illumination apparatus
FR2467425A1 (fr) * 1979-10-15 1981-04-17 Savin Corp Appareil de balayage pour photocopieur
US4498758A (en) * 1982-05-26 1985-02-12 Agfa-Gevaert N.V. Apparatus for transferring xerographic images

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5324830A (en) * 1976-08-18 1978-03-08 Daito Kk Device for deleting scattering of projected light and condensing light for slit exposure copying machine

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3642366A (en) * 1968-12-28 1972-02-15 Canon Kk Copying machine

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3062095A (en) * 1959-07-02 1962-11-06 Xerox Corp Projector optical scanning system
US3554640A (en) * 1968-11-25 1971-01-12 Ibm Drive coupling system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3642366A (en) * 1968-12-28 1972-02-15 Canon Kk Copying machine

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4189763A (en) * 1977-01-25 1980-02-19 Ricoh Company Ltd. Document illumination apparatus
FR2467425A1 (fr) * 1979-10-15 1981-04-17 Savin Corp Appareil de balayage pour photocopieur
US4355883A (en) * 1979-10-15 1982-10-26 Savin Corporation Photocopier scanning apparatus
US4498758A (en) * 1982-05-26 1985-02-12 Agfa-Gevaert N.V. Apparatus for transferring xerographic images

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Publication number Publication date
JPS5081550A (de) 1975-07-02
FR2251851A1 (de) 1975-06-13
FR2251851B1 (de) 1977-10-28
GB1482478A (en) 1977-08-10
DE2357582A1 (de) 1975-05-28
AU7521674A (en) 1976-05-13
NL7414603A (nl) 1975-05-21
DE2357582C2 (de) 1982-08-19
JPS5710425B2 (de) 1982-02-26

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