Silicon micromachined optical device

• US 6,639,713 B2
• Filed: 04/25/2001
• Issued: 10/28/2003
• Est. Priority Date: 04/25/2000
• Status: Expired due to Fees

• Current Assignee: Umachines Incorporated
• Original Assignee: Umachines Incorporated
• Inventors: Dickson, Jeff, Tai, Yu-Chong, Avakian, Aramais, Jiang, Fukang, Chiu, Chen-Wei, Tsao, Tom
• Primary Examiner(s): Ben, Loha
• Assistant Examiner(s): CHOI, WILLIAM C
• Application Number:
  US09/843,024
• Publication Number:
  US 20020135864A1
• Time in Patent Office: 916 Days
• Field of Search: 359/197, 359/198, 359/201, 359/223, 359/204, 359/290, 359/291, 359/318, 345/84, 345/85, 385/16-19
• US Class Current: 359/318
• CPC Class Codes: B81B 2201/031 Thermal actuators
• CPC Class Codes: B81B 2201/045 Optical switches
• CPC Class Codes: B81B 2203/0118 Cantilevers
• CPC Class Codes: B81B 2203/058 Rotation out of a plane parallel to the substrate
• CPC Class Codes: B81B 3/0051 For defining the movement, i.e. structures that guide or limit the movement of an element mechanical arrangements for preventing or damping vibration or shock H01H3/60
• CPC Class Codes: B81C 1/00214 Processes for the simultaneaous manufacturing of a network or an array of similar microstructural devices
• 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 6/3546 NxM switch, i.e. a regular array of switches elements of matrix type constellation
• CPC Class Codes: G02B 6/3566 involving bending a beam, e.g. with cantilever
• CPC Class Codes: G02B 6/3572 Magnetic force magnetic forces controlling reflecting elements in general G02B26/085; magneto-optic devices G02F1/09
• CPC Class Codes: G02B 6/3576 Temperature or heat actuation thermal forces controlling reflecting elements in general G02B26/0866; thermo-optic devices G02F1/0147
• 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: G02B 6/3594 Characterised by additional functional means, e.g. means for variably attenuating or branching or means for switching differently polarized beams

Abstract

An apparatus at least partially intercepts a plurality of light beams propagating along a respective plurality of beam paths. The apparatus includes a single crystal silicon substrate and an array including a plurality of modules. Each module includes a reflector comprising single crystal silicon and a reflector surface lying in a reflector plane substantially perpendicular to the substrate surface. Each module further includes a reflector support which mounts the reflector to move substantially within the reflector plane with a displacement component along the surface normal direction of the substrate surface. Each module further includes a reflector driver responsive to electrical current to selectively move the reflector between a first position and a second position.

Claims

1. An apparatus for at least partially intercepting a plurality of light beams propagating along a respective plurality of beam paths, the apparatus comprising:

a single crystal silicon substrate comprising a substrate surface with a surface normal direction; and

an array comprising plurality of modules, each of the modules comprising;

a reflector comprising single crystal silicon and a reflector surface lying in a reflector plane substantially perpendicular to the substrate surface;

a reflector support which mounts the reflector to move substantially within the reflector plane with a displacement component along the surface normal direction of the substrate surface; and

a reflector driver responsive to electrical current to selectively move the reflector between a first position in which the reflector intercepts at least a portion of one of the beam paths and a second position in which the reflector does not intercept the portion of one of the beam paths, at least a portion of the reflector driver being mounted to the reflector support and conductive to electrical current, such that the reflector moves to the first position when electrical current flows therethrough and moves to the second position when electrical current flow ceases, whereby the movement of the reflectors is individually addressable, and wherein the reflector driver comprises a magnetic actuator comprising;

a magnetic field generated externally from the array; and

an electrical conduit mechanically coupled to the reflector support, whereby the electrical current flowing through the electrical conduit interacts with the magnetic field to generate a force which moves the reflector between the first position and the second position.

2. The apparatus of claim 1, wherein the magnetic field is generated by a permanent magnet.

3. The apparatus of claim 1, wherein the magnetic field is generated by an electromagnet.

4. The apparatus of claim 1, wherein the magnetic actuator further comprises a second electrical conduit mechanically coupled to the reflector support.

5. The apparatus of claim 1, wherein the reflector of at least one of the modules substantially completely intercepts the beam path when in the first position, thereby switching the light beam by deflecting the light beam into a second beam path.

6. The apparatus of claim 1, wherein the first position of the reflector of at least one of the modules is selectable, whereby the reflector in the first position intercepts a selected portion of the light beam.

7. The apparatus of claim 1, wherein the magnetic field is generated by a plurality of north-south pole pairs.

8. An apparatus for at least partially intercepting a plurality of light beams propagating along a respect ye plurality of beam paths, the apparatus comprising:

a single crystal silicon substrate comprising a substrate surface with a surface normal direction; and

an array comprising a plurality of modules, each of the modules comprising;

a reflector comprising single crystal silicon and a reflector surface lying in a reflector plane substantially perpendicular to the substrate surface;

a reflector support which mounts the reflector to move substantially within the reflector plane with a displacement component along the surface normal direction of the substrate surface; and

a reflector river responsive to electrical current to selectively move the reflector between a first position in which the reflector intercepts at least a portion of one of the beam paths and a second position in which the reflector does not intercept the portion of one of the beam paths, at least a portion of the reflector driver being mount d to the reflector support and conductive to electrical current, such that the reflect or moves to the first position when electrical current flows therethrough and moves to the second position when electrical current flow ceases, whereby the movement of the reflectors is individually addressable, and wherein the reflector comprises a portion of the single crystal silicon substrate.

9. A dense array comprising:

a magnet generating a magnetic field which is substantially uniform across a region; and

a plurality of modules in proximity to the region, the plurality of modules in a generally planar array of rows and columns, the rows and columns being generally perpendicular to one another, whereby adjacent modules are spaced from one another by less than or equal to approximately five centimeters, each of the modules comprising;

support;

a flap mechanically coupled to the support;

a reflector coupled to the flap in a generally perpendicular orientation from the flap, the reflector comprising single crystal silicon; and

an electrical conduit formed on the flap, whereby an electrical current flow through the electrical conduit of a selected module creates a force which moves the reflector of the selected module.

10. A method of at least partially intercepting a light beam propagating along a beam path, the method comprising:

providing a light beam propagating along a beam path;

providing a reflector mounted to a movable reflector support, the reflector lying substantially in a plane and comprising single crystal silicon, the reflector mounted to the movable reflector support such that the reflector is movable along a curved path substantially lying in the plane, the reflector movable between a first position in which the reflector intercepts at least a portion of the beam path and a second position in which the reflector does not intercept the portion of the beam path;

providing an electrical conduit mounted to the reflector support, the electrical conduit conductive to electrical current, whereby the reflector moves to the first position when electrical current flows therethrough and moves to the second position when electrical current flow ceases; and

moving the reflector from the second position to the first position by applying an electrical current through the electrical conduit, thereby at least partially intercepting the light beam propagating along the beam path.

11. A method of switching a light beam from propagating along a first beam path to propagating along a second beam path, the method comprising:

providing a light beam propagating along a first beam path;

providing a reflector mounted to a movable reflector support, the reflector lying substantially in a plane and comprising single crystal silicon, the reflector mounted to the movable reflector support such that the reflector is movable along a curved path substantially lying in the plane, the reflector movable between a first position in which the reflector substantially completely intercepts the first beam path and a second position in which the reflector does not substantially completely intercept the first beam path;

providing an electrical conduit mounted to the reflector support, the electrical conduit conductive to electrical current, whereby the reflector moves to the first position when electrical current flows therethrough and moves to the second position when electrical current flow ceases; and

moving the reflector from the second position to the first position by applying an electrical current through the electrical conduit, thereby switching the light beam from propagating along the first beam path to propagating along a second beam path.