Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

LIQUID CRYSTAL PLATEN MASKS

IP.com Disclosure Number: IPCOM000024486D
Original Publication Date: 1980-Oct-31
Included in the Prior Art Database: 2004-Apr-02
Document File: 2 page(s) / 87K

Publishing Venue

Xerox Disclosure Journal

Abstract

This disclosure relates to a modification in the design of the transparent platen of a xerographic copier/duplicator. The modification is the incorporation of a mask within the platen which will indicate to the operator where the original document should be positioned and which will provide the additional function of furnishing a reflective surf ace within the optical cavity beneath the platen which corresponds with the area of the platen not covered by a book or other three-dimensional object.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 59% of the total text.

Page 1 of 2

XEROX DISCLOSURE JOURNAL

LIQUID CRYSTAL PLATEN MASKS

J. D. Rees
M. J. Lenhard

Proposed Classification
U.S. a. 355/74 Int. CI. G03b 27/58

I I n

5

This disclosure relates to a modification in the design of the transparent platen of a xerographic copier/duplicator. The modification is the incorporation of a mask within the platen which will indicate to the operator where the original document should be positioned and which will provide the additional function of furnishing a reflective surf ace within the optical cavity beneath the platen which corresponds with the area of the platen not covered by a book or other three-dimensional object.

The figure shows a top and sectional view of the disclosed platen. Platen 1 is masked by the area 2, the inner dimensions of which define the size of the document to be copied. Layer 3 is a piece of glass having outer dimensions equal to that of the platen, and the mask area of which is coated with a thin, transparent conductive material 5 such as, for example, SnO. Layer 4 is a piece of glass having the same dimensions as layer 3, but its entire surface is coated with the thin, transparent conductive material 5. Sandwiched between glass layers 3 and 4 is a thin layer 6 of a liquid crystal material having the properties that when excited by an electric field, it becomes diffusely reflective and transmitting and when not excited is clear and highly transparent. Such a liquid crystal material is, for example, 20% oleyl cholesteryl c...