VIDEO DETECTION SYSTEM

• US 3,812,287 A
• Filed: 10/24/1972
• Issued: 05/21/1974
• Est. Priority Date: 05/12/1969
• Status: Expired due to Term

• Current Assignee: Jermone H. Lemelson
• Original Assignee: Jermone H. Lemelson
• Inventors: Lemelson, Jermone H.
• Primary Examiner(s): Britton, Howard W.
• Application Number:
  US05/300,249
• Time in Patent Office: 574 Days
• Field of Search: 178/DIG.33,7.83,6.8,DIG.1,DIG.4,DIG.38 235/61.6A 250/217CR 315/10
• US Class Current: 348/155
• CPC Class Codes: G08B 13/19602 Image analysis to detect motion of the intruder, e.g. by frame subtraction
• CPC Class Codes: G08B 13/19632 Camera support structures, e.g. attachment means, poles
• CPC Class Codes: G11B 27/322 used signal is digitally coded
• CPC Class Codes: H04N 1/00358 Type of the scanned marks
• CPC Class Codes: H04N 1/00374 on the same page as at least a part of the image
• CPC Class Codes: H04N 1/2179 Interfaces allowing access to a plurality of users, e.g. connection to electronic image libraries

Abstract

An apparatus and method are provided for automatically detecting a change in an image field such as the appearance of an object in said field or the disappearance of said object. The apparatus which employs a television camera scanning the image field and which generates a video picture signal which is applied to a remote cathode ray tube to provide an image of the field on the screen thereof, may be employed for security purposes to automatically detect images in the image field. An alarm is sounded when one or more particular portions of the image field vary in content.

Claims

1. An electronic system comprising in combination:

a television camera operable to scan an image field which may change in content with time, a television receiver operable to receive the television signals generated by said camera and including an image screen for generating a viewable image of the information scanned by said camera, a photoelectric cell, a photoelectric control operatively connected to said photoelectric cell and operable to generate an electrical signal when the light intensity falling on said photoelectric cell reaches a predetermined level, means for positioning and retaining said photoelectric cell fixed with respect to said receiver and in a location such that it will receive light from a predetermined area of said image screen so as to permit said cell to detect variations in the light generated at said predetermined area of said screen in accordance with variations in the corresponding area of the image field scanned by said television camera to thereby serve as the detector of said variations, a recorder operable to receive television signals generated by said television camera, means for controlling the operation of said recorder including control means operatively connected to said photoelectric control and operable in response to said electrical signal generated thereby when the light received by said photoelectric cell reaches said predetermined level so as to effect the operation of said recorder to record the output of said television camera and to provide a record of the image field scanned by said camera during at least part of the time said light from said predetermined area of said image screen falling on said photoelectric cell is at said predetermined level.

2. An electronic system in accordance with claim 1 including means responsive to said electrical signal generated by said photoelectric control for effecting a recording in said recorder of a signal which is indicative of detection by said photoelectric cell of a variation in the image content of the field scanned by said camera.

3. An electronic system in accordance with claim 2 wherein said means responsive to said electrical signal generated by said photoelectric control includes a digital code signal generator operatively connected to the recording input of said recorder for generating and transmitting code signals, when activated by the signal output of said photoelectric control, to said recorder which code signals are indicative of the time when said photoelectric cell detects when light from that portion of the image screen of said television receiver reaches said predetermined level.