ELECTROMECHANICAL LIGHT VALVE

• US 3,553,364 A
• Filed: 03/15/1968
• Issued: 01/05/1971
• Est. Priority Date: 03/15/1968
• Status: Expired due to Term

• Current Assignee: Lee, Ray H.
• Original Assignee: Lee, Ray H.
• Inventors: Lee, Ray H.
• Application Number:
  US04/713,503
• Time in Patent Office: 1,026 Days
• US Class Current: 359/230
• CPC Class Codes: G09F 9/372 the positions of the elements being controlled by the application of an electric field

Abstract

An electromechanical light valve in an array of many such valves for controlling the transmission of light in continuously changing patterns. Each light valve consists of a housing having grounded conducted walls for shielding the interior thereof from external electrostatic forces produced by surrounding valves in the array or from other external forces. Light from a source enters one end of the housing through a light transparent and electrically insulating panel coated with a conductive film to which is mounted one or more electrostatically controlled leaf shutters. The leaf shutter and the conductive housing walls form a capacitor; connecting a voltage to the leaf shutter sets up a charge thereon thereby causing the shutter to be attracted to the housing walls. Voltages for charging the leaf shutters of all the valves in an array are generated by an XY scanner. A slight modification changes valve from a light transmissive device to a light reflective valve.

Claims

1. An electromechanical light valve for controlling the transmission of light from a source comprising:

a housing having grounded conductive walls for shielding the interior thereof from external electrostatic forces;

mounting means in said housing transmitting light from said source and electrically insulating; and

at least one electrostatically controlled leaf shutter mounted to said means and deflectable in said housing by means of an electrostatic charge thereon generated by an applied voltage.

2. An electromechanical light valve for controlling the transmission of light from a source as set forth in claim 1 wherein said mounting means includes curved surfaces against which said leaf shutter deflects thereby improving the response time of said shutter. 3, An electromechanical light valve for controlling the transmission of light from a source as set forth in claim 1 including means for charging said leaf shutters to a level slightly less than the pull-in voltage of said shutters.

4. An electromechanical light valve for controlling the transmission of light from a source as set forth in claim 1 including means for reducing the air drag on said leaf shutters.

5. An electromechanical light valve for controlling the transmission of light from a source as set forth in claim 1 including filter means at said housing to transmit to light waves having only preselected wavelengths.

6. An electromechanical light valve for controlling the transmission of light from a source comprising:

a housing including means for shielding the interior thereof from external electrostatic forces;

a first set of electrostatically controlled leaf shutters positioned at the inner walls of said housing and deflectable by means of an electrostatic charge thereon; and

a second set of electrostatically controlled leaf shutters positioned at the center of said housing opposite said first set of shutters and deflectable by means of an electrostatic charge thereon generated from an applied voltage, said sets of electrostatically controlled shutters deflectable in a manner to impede the transmission of light through said housing.

7. Apparatus for controlling the transmission of light from a source in a continuously changing pattern comprising:

a plurality of electromechanical light valves each including a housing having means for shielding the interior thereof from external electrostatic forces and at least one electrostatically controlled leaf shutter mounted to a panel at the light source end of said housing and deflectable in said housing by means of an electrostatic charge thereon;

scanning means for connecting a voltage to said electrostatically controlled leaf shutters to generate the electrostatic charge thereon in accordance with a changing program; and

an output panel covering said light valve housings at the end opposite from said source having a conductive inner surface connected to ground.

8. Apparatus for controlling the transmission of light from a source as set forth in claim 7 including means for receiving a video signal connected to said scanning means for programming the operation of said electromechanical light valves.

9. An electromechanical light valve for controlling the reflection of light from a source comprising:

a housing including means for shielding the interior thereof from external electrostatic forces;

means for piping light into the interior of said housing; and

an electrostatically controlled leaf shutter mounted in said housing and deflectable by means of an electrostatic charge thereon, said leaf shutter blocking out light into said housing in a first position and reflecting light from said housing transmitted through said piping means in second position.

10. An electromechanical light valve for controlling the reflection of light from a source as set forth in claim 9 wherein said piping means includes an electrically conductive fiber optic panel for mounting said leaf shutter.

11. Apparatus for controlling the transmission of light from a source in a continuously changing pattern comprising:

a plurality of electromechanical light valves each including;

a housing including means for shielding the interior thereof from external electrostatic forces;

a mounting frame forming a passage for transmitting light from said source to an observer; and

at least one electrostatically controlled leaf shutter mounted between said housing and said mounting frame and deflectable therein by means of an electrostatic charge thereon generated from an applied voltage.

12. An electromechanical light valve for controlling the transmission of light from a source as set forth in claim 11 wherein said housing is of an electrically conductive material and said leaf shutters are in electrical contact with said housing.

13. An electromechanical light valve for controlling the transmission of light from a source comprising:

a housing including means for shielding the interior thereof from external electrostatic forces;

a mounting frame forming a passage for transmitting light from said source to an observer; and

at least one electrostatically controlled leaf shutter mounted between said housing and said mounting frame and deflectable therein by means of an electrostatic charge thereon generated from an applied vOltage;

wherein said mounting frame is an electrically conductive material in electrical contact with said leaf shutters and wherein said housing is an electrically conductive material coated on the inner walls with an electrically insulating material.

14. An electromechanical light valve for controlling the transmission of light from a source as set forth in claim 13 including means for reducing the air drag between said leaf shutters and said electrically insulating coating.