US 4,549,223 A · Reading, printing and copying device

Abstract

A reading, printing and copying device in which a film image sensor, liquid crystal shutter and drive unit are all fabricated upon a single transparent substrate. The film image sensor includes a plurality of individual photosensing elements, each of which is connected to a transparent electrode covered by a liquid crystal layer in the liquid crystal shutter. The drive unit of the device first couples each of the film image sensing units to a charging potential, after which the incident light determines the final potential of each of the electrodes, and hence the transmissivity of the portion of the liquid crystal layer associated with the transparent electrode coupled to the respective photoconductive element. The outputs of the photoconductive elements are also switchably couplable to an output terminal to provide a serial output signal. Light is shone onto the liquid crystal shutter. The amount of light transmitted through the liquid crystal shutter is controlled by the amount of light reflected from an original to be copied falling upon the film image sensor. The light transmitted through the liquid crystal shutter is applied to a photosensitive copying device.

Claims11

Dependent claims

A reading, printing and copying device, comprising:

light sensing means for sensing the intensity of an incident light signal, said light sensing means including photoconductive material;
liquid crystal shutter means having a transmissivity to light controlled by said light sensing means, said liquid crystal shutter means including a first electrode directly connected to said photoconductive material, said light sensing means and said liquid crystal shutter means being fabricated upon a single substrate;
means for applying a first potential to said light sensing means, said light sensing means selectively transmitting said first potential to said liquid crystal shutter means through said directly-connected photoconductive material and first electrode in accordance with said incident light signal intensity;
and
photosensitive copying means positioned to receive light transmitted through said liquid crystal shutter means.

2 more elements

A reading, printing and copying device comprising:

a transparent substrate;
an image sensor fabricated upon a first portion of said transparent substrate, said image sensor comprising a split electrode having a plurality of electrode portions formed on one surface of said transparent substrate, a layer of photoconductive material disposed over said split electrode, a first transparent conductive film layer disposed over said layer of photoconductive material, and an electrode coupled to said first transparent conductive film;
a liquid crystal shutter formed on a second portion of said transparent substrate, said liquid crystal shutter comprising a plurality of regions of a second transparent conductive film layer, each of said regions being coupled to a respective electrode portion of said split electrode;
a liquid crystal layer disposed over said second transparent conductive film layer;
a third transparent conductive film layer formed over said liquid crystal layer;
first and second polarizing plates, said first polarizing plate being disposed over said third transparent conductive film layer and said second polarizing plate being disposed on the opposite surface of said transparent substrate opposite said first polarizing plate;
and
a drive unit fabricated upon a third portion of said transparent substrate.

5 more elements

Dependencies are inferred from the claim text.

Reading, printing and copying device

Life of this patent

Reading, printing and copying device

Life of this patent

Abstract

Claims11