Miniature scanning confocal microscope

• US 5,742,419 A
• Filed: 12/19/1995
• Issued: 04/21/1998
• Est. Priority Date: 11/07/1995
• 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): Phan, James
• Application Number:
  US08/575,687
• Time in Patent Office: 854 Days
• Field of Search: 359/201, 359/202, 359/223, 359/224, 359/368, 359/385, 385/33, 250/201.3
• US Class Current: 359/201.1
• 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 6/357 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

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 scanning optical microscope of the type which includes a single mode optical fiber having one end which serves as a point source of light, and a lens for focusing the light from the end of the fiber onto a point on a focal plane, and for gathering light reflected from said point and focusing said light onto the end of the optical fiber, characterized in that it includes:

a first micro-machined scanning mirror to receive the light from the fiber and scans the light along a first direction, and

a second micro-machined scanning mirror coplanar with said first micro-machined scanning mirror to receive the light from the first mirror and scans said light in an orthogonal direction, whereby the point on the focal plane is scanned in said first and second directions.

2. A scanning optical microscope as in claim 1 which includes an inclined reflector for receiving light from the optical fiber and directing it onto the first micro-machined scanning mirror, and a reflector disposed to receive light from said first micro-machined scanning mirror and reflect it onto the second micro-machined scanning mirror, which directs it to the focusing lens.

3. A scanning optical microscope including:

a silicon substrate including first and second wells;

a first pair of ion-implanted conductive regions in said first well;

a second pair of ion-implanted conductive regions in said second well;

a first micro-machined scanning mirror hingedly supported above said first well for rotation about a first axis;

a second micro-machined scanning mirror hingedly supported above said second well for rotation about a second orthogonal axis;

a conductive reflective film carried on the surface of said first and second scanning mirrors which, together with the conductive regions in said wells, form spaced plates which are electrostatically driven with respect to one another to thereby rotate said mirrors;

an optical fiber serving as a point source of light, said first scanning mirror scanning the light from the optical fiber in a first direction and said second mirror scanning the light in an orthogonal direction; and

a lens for receiving the light scanned by said mirrors and focusing it at scanned points on an image plane and for receiving light reflected from said plane and directing it back to the optical fiber.

4. A scanning optical microscope as in claim 3 which includes an inclined reflector for receiving light from the optical fiber and directing it into the first mirror and a reflector disposed to receive light from the first mirror and reflect it onto the second mirror which directs it to the focusing lens.

5. A scanning optical microscope as in claim 3 wherein the mirrors are coplanar.

6. A scanning optical microscope including:

a silicon substrate including first and second wells;

a first pair of ion-implanted conductive regions in said first well;

a second pair of ion-implanted conductive regions in said second well;

a first micro-machined scanning mirror hingedly supported above said first well for rotation about a first axis;

a second micro-machined scanning mirror hingedly supported above said second well for rotation about a second orthogonal axis;

a conductive reflective film carried on the surface of said first and second scanning mirrors which, together with the conductive regions in said wells, form spaced plates which are electrostatically driven with respect to one another to thereby rotate said mirrors;

an optical fiber serving as a point source of light, said first scanning mirror scanning the light from the optical fiber in a first direction and said second mirror scanning the light in an orthogonal direction; and

an off-axis binary lens for receiving the light scanned by said mirrors and focusing it at scanned points on an image plane and for receiving light reflected from said plane and directing it back to the optical fiber.

7. A scanning optical microscope of the type which includes a single mode optical fiber having one end which serves as a point source of light, and a lens for focusing the light from the end of the fiber onto a point on a focal plane, and for gathering light reflected from said point and focusing said light onto the end of the optical fiber, characterized in that it includes:

a first micro-machined scanning mirror supported for rotation by spaced silicon-nitride hinges for receiving light from the fiber and scanning the light along a first direction, and

a second micro-machined scanning mirror coplanar with said first micro-machined scanning mirror supported for rotation by spaced silicon-nitride hinges for receiving light from the first mirror and scanning said light in an orthogonal direction, whereby the point on the focal plane is scanned in said first and second directions.

8. A scanning optical microscope as in claim 7 which includes an inclined reflector for receiving light from the optical fiber and directing it onto the first mirror, and a reflector disposed to receive light from said first mirror and reflect it onto the second mirror, which directs it to the focusing lens.

9. A scanning optical microscope of the type which includes a single mode optical fiber having one end which serves as a point source of light, and an off-axis binary lens for focusing the light from the end of the fiber onto a point on a focal plane, and for gathering light reflected from said point and focusing said light onto the end of the optical fiber, characterized in that it includes:

a first micro-machined scanning mirror supported for rotation by spaced silicon-nitride hinges for receiving light from the fiber and scanning the light along a first direction, and

a second micro-machined scanning mirror supported for rotation by spaced silicon-nitride hinges for receiving light from the first mirror and scanning said light in an orthogonal direction, whereby the point on the focal plane is scanned in said first and second directions.

10. A scanning optical microscope including:

a silicon substrate including first and second wells;

a first pair of ion-implanted conductive regions in said first well;

a second pair of ion-implanted conductive regions in said second well;

a first micro-machined scanning mirror hingedly supported above said first well by spaced silicon-nitride hinges for rotation about a first axis;

a second micro-machined scanning mirror coplanar with said first micro-machined scanning mirror hingedly supported above said second well by spaced silicon-nitride hinges for rotation about a second orthogonal axis;

a conductive reflective film carried on the surface of said first and second scanning mirrors which, together with the conductive regions in said wells, form spaced plates which are electrostatically driven with respect to one another to thereby rotate said mirrors;

an optical fiber serving as a point source of light, said first scanning mirror scanning the light from the optical fiber in a first direction and said second mirror scanning the light in an orthogonal direction; and

a focusing lens for receiving the light scanned by said mirrors and focusing it at scanned points on an image plane and for receiving light reflected from said plane and directing it back to the optical fiber.

11. A scanning optical microscope as in claim 10 which includes an inclined reflector for receiving light from the optical fiber and directing it into the first mirror and a reflector disposed to receive light from the first mirror and reflect it onto the second mirror which directs it to said focusing lens.

12. A scanning optical microscope including:

a silicon substrate including first and second wells;

a first pair of ion-implanted conductive regions in said first well;

a second pair of ion-implanted conductive regions in said second well;

a first micro-machined scanning mirror hingedly supported above said first well by spaced silicon-nitride hinges for rotation about a first axis;

a second micro-machined scanning mirror hingedly supported above said second well by spaced silicon-nitride hinges for rotation about a second orthogonal axis;

a conductive reflective film carried on the surface of said first and second scanning mirrors which, together with the conductive regions in said wells, form spaced plates which are eIectrostatically driven with respect to one another to thereby rotate said mirrors;

an optical fiber serving as a point source of light, said first scanning mirror scanning the light from the optical fiber in a first direction and said second mirror scanning the light in an orthogonal direction; and

an off-axis binary focusing lens for receiving the light scanned by said mirrors and focusing it at scanned points on an image plane and for receiving light reflected from said plane and directing it back to the optical fiber.