Incoherent image intensity normalization, contour enhancement, and pattern recognition system

• US 4,743,097 A
• Filed: 04/06/1987
• Issued: 05/10/1988
• Est. Priority Date: 04/06/1987
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: The United States Of America As Represented By The Secretary Of The Army
• Inventors: Johnson, John L., Gregory, Don A., Kirsch, James C.
• Primary Examiner(s): Miller, Stanley D.
• Assistant Examiner(s): Duong, Tai V.
• Application Number:
  US07/034,356
• Time in Patent Office: 400 Days
• Field of Search: 350/337, 350/342, 350/174, 350/162.12, 350/162.13, 358/236, 358/240, 358/250, 353/30, 353/31, 364/822
• US Class Current: 349/25
• CPC Class Codes: G06E 3/005 using electro-optical or opto-electronic means

Abstract

Incoherent optical processing techniques are shown which demonstrate image intensity normalization and contour enhancement. A new type of incoherent optical correlator which combines a model of the human neural system with an intensity image convolver. The processor'"'"'s principal element is a Hughes liquid crystal light valve (LCLV). All components are commercially available and used without modification except for a liquid crystal television (LCLV). In operation the invention can be used as either a pre-processor to intensity normalize and edge enhance video scenes for use in pattern recognition applications or as a real-time pattern recognition device within itself, with the addition of an LCTV.

Claims

1. A system comprising a liquid crystal light valve having a read side and a write side, a first image, first and second plane polarizers, first means for transmitting said first image through said first polarizer to the read side in focus for reflection from said read side through said second polarizer, a second image, second means transmitting said second image to the write side out of focus, and detecting means for receiving the reflection after passing through said second polarizer.

2. A system as set forth in claim 1, wherein said first and second polarizers have their polarization aligned parallel to each other.

3. A system as set forth in claim 2, further including a beamsplitter arranged to pass the image from said first means on to said read side and reflect the reflection on to said second polarizer and said detecting means.

4. A system as set forth in claim 2 further comprising a mask with a central opaque spot located between said second means and said second image.

5. A system as set forth in claim 4 wherein said first and said second images are identical.

6. A system as set forth in claim 2 wherein said first and said second images are identical.

7. A system as set forth in claim 6 further comprising a transparency having a reference image thereon, said transparency being located between said second means and said second image for comparing said second image with said reference image.

8. A system as set forth in claim 6 further comprising a liquid crystal TV having the reference image on its screen, and said screen being located between said second means and said second image for comparing said second image with said reference image.