MEMS micromirror and micromirror array
View Patent ↗A micro-electro-mechanical-system (MEMS) micromirror array has an array of micromirrors on a support structure. Each micromirror is pivotally attached to the support structure by a resilient structure. The resilient structure defines a pivot axis. There is an array of electrostatic actuators for pivotally driving the array of micromirrors about the pivot axis. Each electrostatic actuator comprises a first part carried by the support structure, and a second part carried by the corresponding micromirror. An electrostatic sink is mounted to the support structure that shields at least one micromirror from spurious electrostatic actuation.
1. A MEMS micromirror structure comprising:
a movable structure mounted on a support structure by a resilient structure, and at least a portion of the movable structure comprising a micromirror;
an electrostatic actuator for pivotally driving the movable structure, the electrostatic actuator comprising a first part carried by the support structure, and a second part carried by the movable structure;
the resilient structure comprising a first portion and a second portion that is symmetrical to the first portion, each of the first portion and the second portion comprising an I beam connected to a composite structure.
2. The MEMS micromirror structure of claim 1 , wherein the composite structure is one of one or more dual I beam structures, one or more V-shaped structures, and combinations thereof.
3. The MEMS micromirror structure of claim 1 , wherein the electrostatic actuator is a vertical comb drive.
4. The MEMS micromirror structure of claim 3 , wherein one of the first part of the vertical comb drive and the second part of the vertical comb drive comprises fingers that are enclosed within an outer perimeter of the other of the first part or the second part.
5. The MEMS micromirror of claim 4 , wherein the fingers are carried by a carrier portion that is perpendicular to the pivot axis, the carrier portion is connected to an external portion that is outside the outer perimeter of the other of the first part and the second part.
6. The MEMS micromirror of claim 4 , wherein the fingers are arranged parallel to the pivot axis.
7. The MEMS micromirror structure of claim 4 , wherein the fingers are angled relative to the pivot axis.
8. The MEMS micromirror structure of claim 1 , further comprising a cavity between the movable structure and the support structure.
9. The MEMS micromirror structure of claim 1 , further comprising a latch mounted to the support structure by a movable portion that moves in response to an applied voltage between a latching position and a release position as the applied voltage is varied, wherein, in the latching position, the latch secures the movable structure in a desired position.
10. The MEMS micromirror structure of claim 9 , wherein the movable portion is a thermal arched beam actuator.
11. The MEMS micromirror structure of claim 9 , wherein the movable portion comprises first and second parallel thermal connectors that expand at different rates in response to the applied voltage.
12. An array of MEMS micromirrors, and each micromirror comprising:
a movable structure mounted on a support structure by a resilient structure, and at least a portion of the movable structure comprising a micromirror;
an electrostatic actuator for pivotally driving the movable structure, and the electrostatic actuator comprising a first part carried by the support structure, and a second part carried by the movable structure; and
the resilient structure comprising a first portion and a second portion that is symmetrical to the first portion, and each of the first portion and the second portion comprising an I beam connected to a composite structure.