METHOD AND APPARATUS FOR DIGITAL MEASUREMENT WITH AN INDUSTRIAL TELEVISION

• US 3,678,192 A
• Filed: 08/13/1969
• Issued: 07/18/1972
• Est. Priority Date: 08/13/1969
• Status: Expired due to Term

• Current Assignee: Kazuo Kurasawa, Sinya Hashirizaki, Teruo Hiruma, Tomohiko Akuta, Yoshi Honsyo
• Original Assignee: Kazuo Kurasawa, Sinya Hashirizaki, Teruo Hiruma, Tomohiko Akuta, Yoshi Honsyo
• Inventors: Kurasawa, Kazuo, Akuta, Tomohiko, Honsyo, Yoshi, Hashirizaki, Sinya, Hiruma, Teruo
• Primary Examiner(s): Griffin, Robert L.
• Assistant Examiner(s): Eckert, Jr., Richard K.
• Application Number:
  US04/849,651
• Time in Patent Office: 1,070 Days
• Field of Search: 178/6,7.85,7.83,DIG.21,DIG.36 350/156,160,171
• US Class Current: 348/137
• CPC Class Codes: G01B 11/022 by means of tv-camera scanning

Abstract

A method and apparatus for measuring at high precision dimensions of an object to be measured from a remote position by using an image pickup apparatus, wherein a scale graduated at a fixed spacing in the direction of the horizontal scanning line is projected on the photoelectric surface of the image pickup apparatus, the image of the said scale is focused as superposed on the image of the object on the image pickup tube and video signal output of said projected scale lines corresponding to the length of the optical image of the dimension to be measured is taken out as voltage pulses, the number of which is counted.

Claims

1. A method for measuring dimensions of a moving or stationary object from a remote position with an image pickup apparatus:

said method comprising distorting a graduated scale according to the relationship of the distance or opposed angle between the object to be measuring and said image pickup apparatus;

projecting said distorted scale from a first direction onto a photoelectric surface of said image pickup apparatus such that said scale extends in the direction of a horizontal scanning line on said photoelectric surface;

focusing from a second direction onto said photoelectric surface of said image pickup apparatus an image of the object to be measured such that said object image is superposed on an image of said scale, said object being positioned at said distance or opposed angle with respect to said image pickup apparatus;

taking out as voltage pulses a video signal output of the said projected scale corresponding to the length of the optical image of the dimension to be measured by means of a scanning line selecting circuit; and

counting the number of said voltage pulses.

2. A method as claimed in claim 1, wherein said step of distorting comprises aligning a nondistorted scale at said distance or opposed angle, and projecting a distorted image of said nondistorted scale onto a photographic plate located at the normal position of said photoelectric surface, thereby forming said distorted scale.