Illumination arrangement providing for interframe flashdown
AssigneeEastman Kodak Company
InventorAlfred J. Michaloski
Life of this patent
Estimating the term…
Abstract
Diffuse illumination is provided in document copying apparatus for illuminating both the document and an area surrounding the outside edges of the document. The surrounding area reflects illumination similar to the original document to flashdown interframe sections of the photoconductor. Compensation for reduced reflectivity in certain portions of this surrounding area is accomplished by appropriately located specular reflecting surfaces.
Claims9
A copier including a photoconductor for establishing a latent electrostatic image of an object to be copied, said copier comprising:
- supporting structure including a transparent platen for supporting in a first area the object to be copied, said structure defining surfaces in a second area outwardly adjacent said first area having properties suitable for diffusely reflecting light to the photoconductor;
- flash means for simultaneously illuminating the object and said second area with diffuse light to which the photoconductor is sensitive;
- means for projecting light reflected from the object onto said photoconductor in an area defining an image frame on said photoconductor, and for projecting light from said second area onto said photoconductor defining an interframe on said photoconductor in a area outside and adjacent said image frame;
- and
- directional reflecting means in said second area for enchancing the light reflected from said area and projected onto said interframe;
- said directional reflecting means defining a surface oriented to direct light from said illuminating means toward said projecting means.
Projecting apparatus for use in a document copier, said apparatus comprising:
- a platen for supporting in a first area a document to be copied, said platen including a longitudinal edge at which the document is aligned for copying;
- means defining white surfaces outside said first area, said surfaces having properties for efficiently reflecting light in a diffuse manner;
- and
- means defining a specular reflecting surface running longitudinally adjacent said edge for enhancing the reflecting properties outside said first area at said edge and for directing light away from said platen.
In a copier having a transparent platen supported in an opaque frame, means for illuminating said platen and said frame, a photoconductor, and means for focusing an image from said platen onto an area of said photoconductor and for projecting light reflected from said opaque frame onto said photoconductor outwardly of said area, the improvement wherein:
- said platen includes a beveled edge locating a specular reflective surface, said beveled edge and said surface extending at an angle for directionally reflecting light from said illumination means toward said focusing and projecting means for enhancing the light reflected from adjacent said frame to said photoconductor outwardly of said area.
In a document copier including a flat, substantially rectangular platen for supporting in a first area a document to be copied, said platen defining an edge at which the document is to be aligned, and an opposite edge, and being supported at said edges on a frame;
- an endless flexible photoconductor for establishing a latent electrostatic image representing the document, the photoconductor being driven to move continuously in an endless path during a copy cycle when the photoconductor is exposed to the document;
- means for flashing the document with diffuse illumination and for exposing the photoconductor to light reflected from the document to establish the latent image in the photoconductor and thereby defining an image frame on the photoconductor, said means including first and opposite sources of illumination extending parallel to said edge and said opposite edge, respectively;
- the improvement wherein:
- said frame includes means adjacent said first area defining a white surface having suitable properties for efficiently and diffusely reflecting light from said flashing means;
- said means for flashing the document and exposing the photoconductor exposes the photoconductor outside said image frame to light reflected from said white surface means of said frame;
- and
- means are provided at said alignment edge of said platen defining an elongate specular reflecting surface for efficiently and directionally reflecting light from said opposite source of illumination to said photoconductor outside said image area to compensate for losses in light reflected from adjacent said alignment edge.
An illumination-exposure device for use with an electrostatically charged multiframe photoconductor defining pairs of frames and having an interframe area associated with at least one such pair, said device comprising:
- a transparent platen for supporting the document to be illuminated and exposed, said platen being substantially rectangular and having first and second opposed parallel edges;
- an illumination source having first and second elongated lamps, said first lamp being located outside of and parallel to said first edge of said platen and said second lamp being located outside of and parallel to said second edge of said platen;
- said platen having first reflection means located at said first edge of said platen for directing a portion of the light from said second lamp to the interframe area of the photoconductor.
Dependencies are inferred from the claim text.