Environmentally responsive optical microstructured hybrid actuator assemblies and applications thereof

Patent metadata

Field	Value
Publication number	US-2016209642-A1
Application number	US-201514974734-A
Country	US
Kind code	A1
Filing date	Dec 18, 2015
Priority date	Nov 29, 2010
Publication date	Jul 21, 2016
Grant date	—

Abstract

Microstructured hybrid actuator assemblies in which microactuators carrying designed surface properties to be revealed upon actuation are embedded in a layer of responsive materials. The microactuators in a microactuator array reversibly change their configuration in response to a change in the environment without requiring an external power source to switch their optical properties.

First claim

1 - 20 . (canceled)

21 . An apparatus comprising:
a substrate with a surface; an environmentally responsive hydrogel polymer layer disposed on a region of the surface; and a plurality of microactuators embedded in the environmentally responsive hydrogel polymer layer, microactuators of the plurality of microactuators configured to move from a first position to a second position, in response to a volume change of the environmentally responsive hydrogel polymer layer from a first volume to a second volume, such that the movement of the microactuators alters an optical property of the apparatus, and
the volume change of the environmentally responsive hydrogel polymer layer controlled by a stimulus including at least one of a chemical species concentration change or an ion concentration change.

22 . The apparatus of claim 21 , wherein the microactuators are configured to deform in response to the volume change.

23 . The apparatus of claim 22 , wherein the microactuators are configured to bend in response to the volume change.

24 . The apparatus of claim 22 , wherein the microactuators are configured to twist or buckle in response to the volume change.

25 . The apparatus of claim 22 , wherein the microactuators are configured to tilt in response to the volume change.

26 . The apparatus of claim 21 , wherein the microactuators are cylindrical objects that are fully embedded or partially embedded in the hydrogel layer.

27 . The apparatus of claim 21 , wherein the plurality of microactuators is an array of deformable geometrical features including posts, blades, cones, pyramids or inverted cones embedded fully or partially in the hydrogel layer.

28 . The apparatus of claim 21 , wherein each microactuator of the plurality of microactuators has a cross-sectional shape, defined in a plane parallel to the surface of the substrate, that is circular, square, oval, rectangular or irregular.

29 . The apparatus of claim 21 , wherein each microactuator of the plurality of microactuators has a cross-sectional shape, defined in a plane parallel to the surface of the substrate, that is a combination of at least two of: circular, square, oval, rectangular and irregular.

30 . The apparatus of claim 21 , wherein each microactuator of the plurality of microactuators has a cross-sectional shape, defined in a plane parallel to the surface of the substrate, that is symmetric or asymmetric.

31 . The apparatus of claim 21 , wherein each microactuator of the plurality of microactuators has an undulated sidewall.

32 . The apparatus of claim 31 , wherein the undulated sidewall comprises a periodic pattern.

33 . The apparatus of claim 21 , wherein each microactuator of the plurality of microactuators has a cross-sectional shape, defined in a plane normal to the surface of the substrate, that is step-wise or continuous gradient along an axis extending from the surface of the substrate to a distal end of the corresponding microactuator.

34 . The apparatus of claim 21 , wherein the plurality of microactuators is arranged in a periodic array.

35 . The apparatus of claim 21 , wherein the microactuators are cylindrical objects with undulated sidewalls, the microactuators fully embedded or partially embedded in the hydrogel layer.

36 . The apparatus of claim 21 , wherein a first end of each microactuator is in direct contact with the surface.

37 . The apparatus of claim 21 , wherein a first end of one or more microactuators is spaced apart from the surface.

38 . The apparatus of claim 21 , wherein a first end of one or more of the microactuators is attached to the surface.

39 . The apparatus of claim 21 , wherein different portions of the environmentally responsive hydrogel polymer layer are responsive to different stimuli or to a different combination of stimuli.

40 . The apparatus of claim 21 , wherein the microactuators are embedded in the environmentally responsive hydrogel polymer layer in a plurality of microarray patterns.

41 . The apparatus of claim 21 , wherein the plurality of microactuators displays a pattern upon actuation.

42 . The apparatus of claim 21 , wherein the microactuators have a dimension perpendicular to the surface in a range of 1 μm to about 1 mm.

43 . The apparatus of claim 21 , wherein the microactuators have a cross-sectional thickness in a range of 10 nm to about 1,000 μm.

44 . An apparatus comprising:
a substrate with a surface; an environmentally responsive hydrogel polymer layer disposed on the surface; a first group of microactuators at least partially embedded in a first region of the environmentally responsive hydrogel polymer layer; and a second group of microactuators at least partially embedded in a second region of the environmentally responsive hydrogel polymer layer, microactuators of the first group of microactuators configured to move from a first position to a second position, in response to a volume change of the first region of the environmentally responsive hydrogel polymer layer from a first volume to a second volume, such that the movement of the microactuators of the first group of microactuators alters a first optical property of the apparatus, microactuators of the second group of microactuators configured to move from a first position to a second position, in response to a volume change of the second region of the environmentally responsive hydrogel polymer layer from a first volume to a second volume, such that the movement of the microactuators of the second group of microactuators alters a second optical property of the apparatus, the volume change of the first region of the environmentally responsive hydrogel polymer layer controlled by a first stimulus, and the volume change of the second region of the environmentally responsive hydrogel polymer layer controlled by a second stimulus.

45 . The apparatus of claim 44 , wherein the first stimulus and/or the second stimulus includes at least one of: a pH change, a chemical species concentration change, or an ion concentration change.

46 . The apparatus of claim 44 , wherein the first stimulus includes a first chemical species concentration change, and the second stimulus includes a second chemical species concentration change that differs from the first chemical species concentration change.

47 . The apparatus of claim 44 , wherein the microactuators of the first group of microactuators and/or the microactuators of the second group of microactuators have a dimension perpendicular to the surface in a range of 1 μm to about 1 mm.

48 . The apparatus of claim 44 , wherein the microactuators of the first group of microactuators and/or the microactuators of the second group have a cross-sectional thickness in a range of 10 nm to about 1,000 μm.

49 . An apparatus comprising:
a substrate with a surface; an environmentally responsive hydrogel polymer layer disposed on the surface; a first group of microactuators at least partially embedded in a first region of the environmentally responsive hydrogel polymer layer; and a second group of microactuators at least partially embedded in a second region of the environmentally responsive hydrogel polymer layer, microactuators of the first group of microactuators configured to move from a first position to a second position, in response to a volume change of t

Assignees

• Harvard College

Inventors

• Aizenberg Joanna
• Aizenberg Michael
• Kim Philseok

Classifications

• B81B2207/053

  of movable structures · CPC title

• B81B3/0032

  Structures for transforming energy not provided for in groups B81B3/0021 - B81B3/0029 · CPC title

• G02B26/0833 Primary

  the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD (G02B26/0825 takes precedence; micromechanical devices in general B81B) · CPC title

• G02B26/0808

  by means of one or more diffracting elements · CPC title

• B81B2201/038

  Microengines and actuators not provided for in B81B2201/031 - B81B2201/037 · CPC title