Wobble correcting monogon scanner for a laser imaging system

• US 6,094,287 A
• Filed: 12/03/1998
• Issued: 07/25/2000
• Est. Priority Date: 12/03/1998
• Status: Expired due to Fees

• Current Assignee: CareStream Health Incorporated
• Original Assignee: Eastman Kodak Company
• Inventors: Li, Peter Y.
• Primary Examiner(s): Spyrou, Cassandra
• Assistant Examiner(s): BOUTSIKARIS, LEONIDAS
• Application Number:
  US09/205,547
• Time in Patent Office: 600 Days
• Field of Search: 359/201, 359/211, 359/212, 359/216, 359/217, 359/218, 359/219, 359/220, 359/226, 359/834, 358/491, 358/493, 358/497
• US Class Current: 359/211.1
• CPC Class Codes: G02B 26/108 having one or more prisms as scanning elements
• CPC Class Codes: H04N 1/0607 Scanning a concave surface, e.g. with internal drum type scanners H04N1/0657 takes precedence
• CPC Class Codes: H04N 1/0621 using a picture-bearing surface stationary in the main-scanning direction

Abstract

Disclosed is an optical scanner assembly for producing an image on imaging material positioned on an internal surface of a curved film platen. The scanner assembly includes a light source for producing a light beam representative of the image to be produced on the imaging material, a reflective system rotatable about a rotation axis, and a toric lens. The reflective system comprises a scan optic defined by a pentaprism and a cylindrical lens. A first reflective surface of the pentaprism receives the light beam from the light source and reflects the light beam to a second reflective surface of the pentaprism. The light beam is further reflected by the second reflective surface towards the imaging material through the cylindrical lens and the toric lens, which act to focus the light beam onto the imaging material to produce the image thereon. The cylindrical and toric lenses in conjunction with the pentaprism correct for wobble along the rotation axis of the reflective system caused by bearing and mechanical inaccuracies in a drive mechanism of the reflective system.

Claims

1. An optical scanner assembly for producing an image on imaging material positioned on an internal surface of a curved film platen, the scanner assembly comprising:

a light source for producing a light beam representative of the image to be produced on the imaging material, the light beam exiting the light source along a beam axis; and

a reflective system rotatable about a rotation axis substantially coincident with the beam axis, the reflective system including;

a scan optic, the scan optic including;

a first reflective surface for receiving the light beam from the light source and reflecting the light beam; and

a second reflective surface for receiving the light beam reflected from the first reflective surface and reflecting the light beam toward the imaging material on the internal surface of the curved film platen;

a lens device for focusing the light beam onto the imaging material to produce the image thereon; and

a further lens device that is stationary with respect to the rotatable reflective system, the further lens device receiving the light beam focused by the lens device, the further lens device further focusing the light beam onto the imaging material to produce the image thereon.

2. The optical scanner assembly of claim 1 wherein the scan optic is a prism.

3. The optical scanner assembly of claim 2 wherein the prism is a pentaprism.

4. The optical scanner assembly of claim 3 wherein the pentaprism includes:

first and second internal reflective surfaces that constitute the first and second reflective surfaces, respectively;

an incident surface for receiving the light beam from the light source, the incident surface being distal to the first internal reflective surface; and

an exiting surface distal to the second internal reflective surface for receiving the light beam reflected from the second internal reflective surface.

5. The optical scanner assembly of claim 4 wherein the incident surface faces the light source, and wherein the incident surface is transparent such that the light beam enters the pentaprism by passing through the incident surface.

6. The optical scanner assembly of claim 4 wherein the exiting surface faces the imaging material positioned on the internal surface of the curved film platen, and wherein the exiting surface is transparent such that the first and second internal reflective surfaces cooperatively direct the light beam through the exiting surface.

7. The optical scanner assembly of claim 4 wherein the lens device is on an exterior portion of the exiting surface of the pentaprism.

8. The optical scanner assembly of claim 7 wherein the lens device is a cylindrical lens.

9. The optical scanner assembly of claim 8 wherein the cylindrical lens has a center of curvature axis, and wherein the center of curvature axis is substantially parallel to the beam and rotation axes.

10. The optical scanner assembly of claim 9 wherein the cylindrical lens is integral with the exterior portion of the exiting surface of the pentaprism.

11. The optical scanner assembly of claim 9 wherein the cylindrical lens is a separate cylindrical lens that is secured to the exterior portion of the exiting surface of the pentaprism.

12. The optical scanner assembly of claim 9 wherein the cylindrical lens is a plastic material cast onto the exterior portion of the exiting surface of the pentaprism.

13. The optical scanner assembly of claim 1 wherein the lens device is a cylindrical lens.

14. The optical scanner assembly of claim 13 wherein the cylindrical lens has a center of curvature axis, and wherein the center of curvature axis is substantially parallel to the beam and rotation axes.

15. The optical scanner assembly of claim 14 wherein the scan optic further includes:

a transparent output surface distal to the second reflective surface such that the light beam passes through the transparent output surface, the cylindrical lens being on an exterior portion of the output surface of the scan optic.

16. The optical scanner assembly of claim 15 wherein the cylindrical lens is integral with the exterior portion of the output surface of the scan optic.

17. The optical scanner assembly of claim 15 wherein the cylindrical lens is a separate cylindrical lens that is secured to the exterior portion of the output surface of the scan optic.

18. The optical scanner assembly of claim 15 wherein the cylindrical lens is a plastic material cast onto the exterior portion of the output surface of the scan optic.

19. The optical scanner assembly of claim 1 wherein the light source is a laser assembly, and wherein the light beam is a laser beam.

20. The optical scanner assembly of claim 1 wherein the lens device focuses the light beam in a first plane, and wherein the further lens device focuses the light beam in a second plane perpendicular to the first plane.

21. The optical scanner assembly of claim 20 wherein the lens device is a cylindrical lens, and wherein the further lens device is a toric lens.

22. An optical scanner assembly for producing an image on imaging material positioned on an internal surface of a curved film platen, the scanner assembly comprising:

a light source for producing a light beam representative of the image to be produced on the imaging material, the light beam exiting the light source along a beam axis;

a scan optic rotatable about a rotation axis substantially coincident with the beam axis, the scan optic including;

first reflective surface for receiving the light beam from the light source and reflecting the light beam; and

a second reflective surface for receiving the light beam reflected from the first reflective surface and reflecting the light beam toward the imaging material on the internal surface of the curved film platen;

a drive mechanism for rotating the scan optic about the rotation axis; and

a system for focusing the light beam onto the imaging material to produce the image thereon, the focusing system including;

a first tens device and focusing the light beam on said imaging material; and

a second lens device for receiving the light beam focused by the first lens device, the second lens device further focusing the light beam to produce the image on the imaging material on the internal surface of the curved film platen.

23. The optical scanner assembly of claim 22 wherein the first lens device focuses the light beam in a first plane, and wherein the second lens device focuses the light beam in a second plane perpendicular to the first plane.

24. The optical scanner assembly of claim 23 wherein the first lens device is a cylindrical lens, and wherein the second lens device is a toric lens.

25. The optical scanner assembly of claim 22 wherein the first lens device is part of the scan optic so as to be rotatable therewith.

26. The optical scanner assembly of claim 25 wherein the second lens device is stationary with respect to the first lens device that is rotatable with the scan optic.

27. A method of producing an image on imaging material positioned on an internal surface of a curved film platen using an optical scanner assembly, the method comprising the steps of:

directing a light beam representative of the image to be produced on the imaging material along a beam axis;

reflecting the light beam using a first reflective surface;

further reflecting the light beam, reflected from the first reflective surface, using a second reflective surface;

focusing, in only a first plane, the light beam reflected from the second reflective surface using a first lens device; and

further focusing, in only a second plane that is perpendicular to the first plane, the light beam reflected from the second reflective surface using a second lens device, to produce the image on the imaging material on the internal surface of the curved film platen.

28. The method of claim 27 wherein the steps of reflecting, further reflecting and focusing include the step of:

rotating in unison the first reflective surface, the second reflective surface and the first lens device.