Imaging system utilizing an oscillating gradient index lens array
AssigneeXerox Corporation
InventorJames D. Rees
Life of this patent
Estimating the term…
Abstract
The present invention is directed to optical imaging systems which utilize linear lens arrays and particularly gradient index lens arrays as the means for projecting light images onto a photosensitive image member. Exposure modulation at the image plane is reduced by oscillating the lens array during an exposure interval, the oscillating period and excursion distance being dependent upon the type of imaging environment the lens is used in. For document copying applications, the requirement for a two-row array to provide minimum exposure modulation is reduced so that a one-row lens array is enabled. For printer and RIS scanning functions, oscillation of a two-row array enables improved system efficiency and hence greater image irradiance and exposure.
Claims18
An optical imaging system including a plurality of gradient index optical fibers combined into at least a single row to form a linear lens array, said array positioned between an object plane and a photosensitive image plane and adapted to transmit and image, during an exposure interval, light from an object lying in the object plane onto the image plane, said system further including means for laterally oscillating the lens array, during an exposure interval, so as to reduce exposure non-uniformity at said image plane.
An imaging system wherein a document at an object plane is to be reproduced at a photosensitive image plane at 1:1 magnification, the system comprising, in combination:
- a linear lens array for forming erect images at unity magnification at said image plane positioned between the object and image plane,
- means for incrementally illuminating the document during an exposure interval,
- means for providing relative movement between the document, lens array and image plane, and
- means for laterally oscillating the lens array during an exposure interval.
A method for reducing non-uniformity of images formed at a photosensitive image plane by a linear lens array comprising the steps of:
- positioning the lens array equidistant an object and image plane,
- directing an image radiation pattern into the entrance face of the lens array,
- providing relative movement between the object plane, lens array and image plane so as to enable a scanning function, and
- laterally oscillating the lens array during the scanning function.
Dependencies are inferred from the claim text.