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

Pattern Matching for Discrete Position Sensing in Scanner-Based Input/Output Devices

IP.com Disclosure Number: IPCOM000040627D
Original Publication Date: 1987-Dec-01
Included in the Prior Art Database: 2005-Feb-02
Document File: 3 page(s) / 41K

Publishing Venue

IBM

Related People

Ho, K: AUTHOR [+4]

Abstract

A technique is described whereby pattern matching is utilized for the discrete position sensing in a printer/scanner input/output (I/O) device. The concept is unique in that a separate positioning sensor is eliminated, as compared with prior art, and the scanner output provides intelligent information while a marker is active. (Image Omitted) Typically, when a hard copy output device is used to record information, marking of the information is achieved by the relative motion of paper with respect to the marking element. One exception would be the laser printer. The coordinates of motion of a typical printer/scanner, as shown in Fig. 1, position the information through the use of a stepper motor or a separate sensor device.

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 53% of the total text.

Page 1 of 3

Pattern Matching for Discrete Position Sensing in Scanner-Based Input/Output Devices

A technique is described whereby pattern matching is utilized for the discrete position sensing in a printer/scanner input/output (I/O) device. The concept is unique in that a separate positioning sensor is eliminated, as compared with prior art, and the scanner output provides intelligent information while a marker is active.

(Image Omitted)

Typically, when a hard copy output device is used to record information, marking of the information is achieved by the relative motion of paper with respect to the marking element. One exception would be the laser printer. The coordinates of motion of a typical printer/scanner, as shown in Fig. 1, position the information through the use of a stepper motor or a separate sensor device. The concept described herein utilizes the scanner to extract discrete positional information, by using a pattern matching technique. A liquid crystal device (LCD) based reference marker/scanner 10, as shown in Fig. 2, is used to generate patterns with back lighting under position sensing mode. (The LCD is deactivated during printing or scanning mode). In print mode, scanner 10 is exposed to an externally placed reference of the pattern, which can be a stored image of the pattern in memory of a computer used for control. The scanner produces a bit string of 1's and 0's which are related to the position and the pattern geometry. The actual size of the bit string is determined by the size of the window of the scanner. For example, assuming a stored image corresponds to bit string S11 and the scanner output corresponds to bit string S12, where both bit strings are: S11 = 1 0 0 0 0 1 0 0 0 0 1, then the SUM-of-AND corresponding to S11 and S12 is defined as: SUM ( S11 AND S12 ) = 3. When the scanner is shifted in position corresponding to a single bit, the new S12 is e...