公开(公告)号：US3626384A

公开(公告)日：1971-12-07

申请号：US3626384D

申请日：1969-12-23

Applicant: IBM

Inventor： DAVIS JONATHAN B ,  EDWARDS NATHEN P ,  HERD HAROLD H

IPC: G01R17/00 ,  G06F17/40 ,  G01D21/00 ,  G06F7/00

CPC classification number: G01R17/00

Abstract: A method is provided for reducing measured data to representative coefficient values. The data relates to physical energy collected and measured by a physical sensor, and therefore, the measured data includes noise. In the method which may be carried out by programming a general purpose digital computer, the measured data values are first processed to remove the linear trend. The resultant values are then processed to provide the maximum number of coefficient values which represent the measured data values. A certain number of the set of coefficient values represent the portion of the measurements which is substantially noise, and may be eliminated. The method therefore includes a process for determining a number of coefficients of the total set which represent the measured data with minimum error where minimum error is defined as minimum stochastic uncertainty.

公开(公告)号：CA1009756A

公开(公告)日：1977-05-03

申请号：CA182824

申请日：1973-10-09

Applicant: IBM

Inventor： BUCKINGHAM ROBERT L ,  DAVIS JONATHAN B ,  HERD HAROLD H

IPC: G06K7/10 ,  G06T1/00

Abstract: What is disclosed is an optical scanner for reading bar codes. The scanner is designed to be held by hand and moved above and across the bar code which is printed on a suitable record substrate. The scanner is composed of a suitable casing containing lamps in the lower portion thereof which illuminate the bar coded record. The illumination is reflected through a unique aperture in the lower surface of the scanner and directed onto a light sensor arrangement such as a photocell. The code marks are in the form of code bars such as black lines separated by white portions. The code consists of "single" code bars and "double" code bars which are, in one embodiment, twice the width of the "single" bars. The aperture arrangement of the scanner is designed according to a scheme such that the resultant signal from the detection of a single bar will always be a known fraction, such as one-half, the amplitude of the signal produced by the detection of a double bar regardless of the changes in speed at which the hand-held scanner is moved across the bar coded record.