Miniature scanning confocal microscope

• US 6,007,208 A
• Filed: 12/24/1997
• Issued: 12/28/1999
• Est. Priority Date: 12/19/1995
• Status: Expired due to Term

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Kino, Gordon S., Dickensheets, David L.
• Primary Examiner(s): Spyrou, Cassandra
• Assistant Examiner(s): SIKDER, MOHAMMAD YUNUS
• Application Number:
  US08/998,187
• Time in Patent Office: 734 Days
• Field of Search: 359/872, 359/873, 359/874, 359/220, 359/221, 359/223, 359/224, 359/225, 359/226, 359/197, 359/198, 359/203, 359/201, 359/202
• US Class Current: 359/872
• CPC Class Codes: G02B 2006/12104 Mirror; Reflectors or the like
• CPC Class Codes: G02B 21/0028 specially adapted for specific applications, e.g. for endoscopes, ophthalmoscopes, attachments to conventional microscopes
• CPC Class Codes: G02B 21/0048 scanning mirrors, e.g. rotating or galvanomirrors, MEMS mirrors
• CPC Class Codes: G02B 21/006 focusing arrangements; selection of the plane to be imaged
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 6/241 Light guide terminations
• CPC Class Codes: G02B 6/3512 the optical element being reflective, e.g. mirror
• CPC Class Codes: G02B 6/3518 the reflective optical element being an intrinsic part of a MEMS device, i.e. fabricated together with the MEMS device MEMS devices in general B81B; manufacture of MEM devices in general B81C; micromechanical devices controlling the direction of light G02B26/0833
• CPC Class Codes: G02B 6/357 Electrostatic force electrostatic forces controlling reflecting elements in general G02B26/0841
• CPC Class Codes: G02B 6/3584 constructional details of an associated actuator having a MEMS construction, i.e. constructed using semiconductor technology such as etching MEMS per se B81B, B81C
• CPC Class Codes: Y10S 359/90 Methods
• CPC Class Codes: Y10T 156/10 Methods of surface bonding and/or assembly therefor

Abstract

A scanning optical microscope which includes an optical fiber which serves as a point source of light and for collecting reflected light is disclosed. A lens for focusing the light from the optical fiber onto an image plane and for gathering light reflected from the image plane and focusing it into the optical fiber is also disclosed, together with a scanning mechanism for scanning the light to scan a field of view.

Claims

1. A microscanning apparatus, comprising:

a semiconductor substrate;

a pivot plate coupled to the semiconductor substrate and pivotable about an axis relative to the substrate, the pivot plate including;

an external face having a first terminal coupled thereto;

an internal face positioned between the external face and the substrate;

a depletion region between the external and internal faces formed during an application of voltage wherein said application of voltage between said first terminal and said substrate causes the plate to pivot; and

a reflective surface that is pivotable in response to pivoting of the pivot plate.

2. A microscanning apparatus as in claim 1 in which the external face of said plate includes a terminal on each side of said semiconductive pivot axis and depletion regions are associated with each terminal whereby drive voltages selectively applied between said terminals and the substrate cause the plate to pivot.

3. A microscanning apparatus as in claim 1 or 2 in which the plate is semiconductive material and a p-n junction is formed between said respective terminal and the semiconductive material whereby the semiconductive material is depleted of carriers by application of the drive voltage to the respective terminal.

4. A microscanning apparatus as in claim 3 in which the semiconductive material is silicon.

5. A microscanning apparatus as in claim 1 or 2 in which the plate is formed in a wafer of semiconductive material by micromachining to define said plate and semiconductive hinges on said pivot axis.

6. A microscanning apparatus as in claim 5 in which the semiconductive hinges are silicon nitride.

7. A microscanning apparatus as in claims 1 or 2 in which said reflective surface forms said first terminal.

8. A microscanning apparatus as in claim 5 wherein said substrate includes a well and said wafer is carried by the surface of said substrate with the plate disposed above the well whereby the plate can pivot about its pivot axis.

9. A mirror for a microscanning device, comprising:

a plate of a semiconductive material pivotably coupling to a supporting structure, the plate including a reflective surface positioned for exposure when the plate is coupled to the supporting structure;

a semiconductor junction formed in the plate; and

wherein said plate is formed in a wafer of semiconductor material of one conductivity type by micromachining and a region of opposite conductivity type is formed in said plate to form said semiconductor junction and hinges pivotably support said plate on said wafer.

10. A mirror as in claim 9 in which spaced semiconductor junctions are formed in said plate and terminals are connected to said regions of opposite conductivity type for selectively depleting the plate semiconductive material associated with each junction.

11. A mirror as in claim 9 or 10 in which the support structure is semiconductive material.

12. A mirror as in claim 10 in which drive voltages are selectively applied between said terminals and said support structure to pivot the mirror.

13. An electrically actuated scanner as in claim 12 in which said plate of semiconductive material is of one conductivity type and a region of opposite conductivity type electrically connects each of the spaced electrodes to the plate of semiconductive material.

14. An electrically actuated scanner as in claim 11 or 12 in which said hinge is silicon nitride.

15. A electrically actuated scanner, comprising:

a substrate;

a mirror body having a first semiconductor region having a first set of electrical properties, a second semiconductor region having a second set of electrical properties different from first set, and a barrier region disposed between the first and second regions, the barrier region forming a barrier to limit electron flow between the first and second regions;

a hinge coupled between the substrate and the mirror body and configured to pivotably couple the mirror plate to the substrate; and

first and second terminals coupled to the first semiconductor region and to the substrate respectively.

16. An electrically actuated scanner as in claim 15 in which the mirror body and the binge coupled between the substrate and mirror body are formed by micromachining a semiconductive material.

17. An electrically actuated scanner as in claim 15 including spaced second conductor regions.

18. An electrically actuated scanner as in claim 16 or 17 in which said hinge is silicon nitride.

19. A micromechanical device comprising:

a base;

a movable assembly linked to the base, the movable assembly including a first member having an integral first region of a first material and an integral second region of a second material, wherein the first region has a first composition including a first semiconductor material and the second region has a second composition different from the first composition, the first and second compositions having different electrical properties, the movable assembly being responsive to periodic electrostatic forces to move in a predetermined periodic pattern relative to the base; and

a first section in the base having a terminal for electrical control, the first section being aligned with the movable assembly and positioned to produce an electric field extending from the first section to the first or second regions.

20. The device of claim 19 wherein the first region includes second regions of semiconductor material.

21. The device of claim 20 wherein the second semiconductor material is doped differently from the first semiconductor material.

22. The device of claim 19 wherein the movable member is torsionally coupled to the base.

23. The device of claims 19, 20, 21, or 22 in which the first region of a first material supports a mirror.