SOLID STATE SCANNING BY DETECTING THE RELIEF PROFILE OF A SEMICONDUCTOR BODY

• US 3,656,837 A
• Filed: 10/14/1970
• Issued: 04/18/1972
• Est. Priority Date: 10/21/1969
• Status: Expired due to Term

• Current Assignee: STC PLC (f/k/a Standard Telephones and Cables)
• Original Assignee: Carl Peter Sandbank
• Inventors: Sandbank, Carl Peter
• Primary Examiner(s): Lawrence, James W.
• Assistant Examiner(s): Nelms, D. C.
• Application Number:
  US05/080,616
• Time in Patent Office: 552 Days
• Field of Search: 250/211R,237R,211J,237Q,213,199 307/311 356/129 350/160,150,151,161,162SF 178/7.3D,7.87,7.88
• US Class Current: 359/291
• CPC Class Codes: G02F 1/015 based on semiconductor elements having potential barriers, e.g. having a PN or PIN junction G02F1/03 takes precedence
• CPC Class Codes: G02F 1/11 based on acousto-optical elements, e.g. using variable diffraction by sound or like mechanical waves acousto-optical deflection G02F1/33
• CPC Class Codes: H04N 5/7425 the modulator being a dielectric deformable layer controlled by an electron beam, e.g. eidophor projector

Abstract

A solid state scanning system includes a body of semiconductive material, such as cadmium sulfide, which exhibits moving high field instability effects, and a light projection system having Schlieren optics to detect surface disturbances caused by a propagating high field domain nucleated within the semiconductor body. The light is preferably directed onto the semiconductor surface by a plurality of louvered mirror strips which also detect the light reflections therefrom. The system may also include a display means to show the relief profile of the surface disturbances in the form of a raster of brightness information representing variations in the voltage across the domain which occurs during the propagation. A layer of a high coupling constant material can be provided on the device to enhance the disturbance effect. A liquid or plastic film can also be used on the device to introduce memory in the system.

Claims

2. A system as claimed in claim 1 wherein said means for causing a high field domain includes means for modulating the voltage across said semiconductor body.

3. A system as claimed in claim 2 in which said semiconductive body is of a piezo-electric semiconductor material.

4. A system as claimed in claim 2 wherein said detecting means includes a source of light and means for directing said light onto said surface and for sensing changes in the angle of reflection of said light from said surface.

5. A system as claimed in claim 4 wherein said surface of said semiconductive body includes a layer of a material for enhancing the surface disturbances.

6. A system as claimed in claim 4 in which the surface of the semiconductive body is provided with a layer of a material for providing a memory effect of the surface disturbances.

7. A system as claimed in claim 4 wherein said means for directing light and sensing changes in reflection includes a plurality of louvered mirror strips having predetermined spacing therebetween.

8. A system as claimed in claim 7 including a display screen for displaying a raster of brightness information from said louvered strips.