Imaging apparatus which includes a light-valve array having electrostatically deflectable elements

• US 4,805,038 A
• Filed: 07/30/1987
• Issued: 02/14/1989
• Est. Priority Date: 07/30/1987
• Status: Expired due to Term

• Current Assignee: Eastman Kodak Company
• Original Assignee: Eastman Kodak Company
• Inventors: Seligson, Joel L.
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): Svihla, Randall S.
• Application Number:
  US07/079,382
• Time in Patent Office: 565 Days
• Field of Search: 350/96.15, 350/96.13, 350/96.20, 350/269, 350/270, 350/275, 350/359, 358/199, 358/200, 358/236, 358/296, 358/298, 358/300, 358/302, 346/107 R, 346/108
• US Class Current: 358/296
• CPC Class Codes: B41J 2/45 using light-emitting diode [LED] or laser arrays
• CPC Class Codes: G02B 26/103 having movable or deformable optical fibres, light guides or waveguides as scanning elements light guides per se G02B6/00
• CPC Class Codes: G02B 6/3502 involving direct waveguide displacement, e.g. cantilever type waveguide displacement involving waveguide bending, or displacing an interposed waveguide between stationary waveguides
• CPC Class Codes: G02B 6/3552 1x1 switch, e.g. on/off switch
• CPC Class Codes: G02B 6/3566 involving bending a beam, e.g. with cantilever
• CPC Class Codes: G02B 6/357 Electrostatic force electrostatic forces controlling reflecting elements in general G02B26/0841
• CPC Class Codes: H04N 1/036 for optical reproduction

Abstract

Imaging apparatus is disclosed for exposing a recording medium to produce an image in accordance with information contained in an electrical signal. The apparatus comprises a light source, optical means for imaging light onto the recording medium, and a light-valve array to control the light reaching selected areas of the recording medium. In order to provide an improved means for controlling the light, the light-valve array is comprised of a plurality of electrostatically deflectable elements each of which contains a transmitter waveguide for transmitting light from the source to a receptor waveguide. The elements can be deflected from a first position in which the transmitter and receptor waveguides are axially aligned for transmitting light therethrough to a second position in which no light can be transmitted from the transmitter waveguides to the receptor waveguides; each of the elements is selectively deflectable in response to an information signal. Light from the receptor waveguides is imaged onto the recording medium.

Claims

1. Imaging apparatus for exposing a recording medium, said apparatus comprising:

a light source;

a light-valve array for receiving light from said source, said array having a plurality of individually deflectable elements, each of said elements including a transmitter multimode waveguide and an electrode, a plurality of receptor multimode waveguides arranged opposite said transmitter waveguides, each of said elements being deflectable upon application of a threshold voltage to the electrode thereof from a first position in which its transmitter waveguide is axially aligned with a corresponding one of said receptor waveguides for transmitting a light beam therethrough to a second position in which no light beam can be transmitted from its transmitter waveguide to said corresponding receptor waveguide, each of said elements being selectively deflectable in response to an information signal; and

optical means for receiving said light beams from said elements and for imaging said light beams on said recording medium.

2. Imaging apparatus, as defined in claim 1, wherein said optical means comprises an array of multimode waveguides, and said array of multimode waveguides includes a multimode waveguide opposite each of said receptor waveguides.

3. Imaging apparatus, as defined in claim 2, wherein said optical means includes a lens array for transmitting individual light beams from said array of multimode waveguides to said recording medium.

4. Imaging apparatus, as defined in claim 3, wherein said array of multimode waveguides has a first end adjacent said light-valve array and a second end adjacent said lens array, and said second end is substantially wider than said first end.

5. Imaging apparatus, as defined in claim 1, wherein said apparatus includes a lens for imaging said light source onto said light-valve array.

6. A light valve comprising:

a body of semiconductive material having an insulating layer thereon, said body having an opening therein which extends through said insulating material to said semiconductor material and defines first and second sections of said body;

an elongated element extending from said first section and projecting over said opening, said element having a bottom layer formed of said insulating material, an electrode on said insulating material, and a transmitter waveguide on said electrode; and

a receptor waveguide on said second section, said receptor waveguide being axially aligned with said transmitter waveguide.

7. A light valve, as defined in claim 6, wherein said transmitter waveguide extends over the insulating material on said first section.

8. A light valve, as defined in claim 6, wherein said waveguides are formed of a material having a higher refractive index than the refractive index of said insulating material.

9. A light valve, as defined in claim 6, wherein said waveguides are formed from poly (methyl methacrylate) (PMMA).

10. A light valve, as defined in claim 6, wherein said insulating material is silicon dioxide.

11. A light valve, as defined in claim 6, wherein said waveguides have a thickness of between about 10 um and about 38 um.

12. A light valve, as defined in claim 6, wherein said element has a length of between about 1 mm and about 6.3 mm.

13. A light valve, as defined in claim 6, wherein said electrode is wider than said transmitter waveguide.

14. A light valve for use in a light-valve array, said light valve comprising an electrostatically deflectable element having a first waveguide and an electrode, and a second waveguide disposed opposite said first waveguide, characterized in that said element includes a layer of material under said first waveguide having a refractive index lower than said first waveguide.

15. A light valve according to claim 14, characterized in that said electrode is under a portion of said first waveguide.