SHAPE-VARIABLE ELECTRONIC DEVICE AND OPERATION METHOD OF THE SAME
20240421729 ยท 2024-12-19
Inventors
- Sung Ryul Yun (Daejeon, KR)
- Inwook HWANG (Daejeon, KR)
- Seongcheol Mun (Daejeon, KR)
- Jung-Hwan YOUN (Daejeon, KR)
Cpc classification
F03G7/06114
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G09F9/372
PHYSICS
F03G7/062
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
G06F1/1601
PHYSICS
G09F9/377
PHYSICS
G09F9/301
PHYSICS
G06F3/016
PHYSICS
G09B21/004
PHYSICS
G06F1/1637
PHYSICS
International classification
H01L27/15
ELECTRICITY
Abstract
Provided are a shape-variable electronic device and an operation method of the same. More specifically, the shape-variable electronic device includes a substrate having a cell region, a light source on the cell region, a flexible layer provided vertically spaced apart from the light source part, a chamber between the light source part and the flexible layer, and a pressure control unit configured to adjust an internal pressure of the chamber. The flexible layer includes a photo-thermal response part configured to emit thermal energy by receiving light emitted from the light source part, and a deformation part of which mechanical stiffness is decreased by receiving the thermal energy from the photo-thermal response part.
Claims
1. A shape-variable electronic device comprising: a substrate having a cell region; a light source part on the cell region; a flexible layer provided vertically spaced apart from the light source part; a chamber between the light source part and the flexible layer; and a pressure control unit configured to adjust an internal pressure of the chamber, wherein the flexible layer comprises: a photo-thermal response part configured to emit thermal energy by receiving light emitted from the light source part, and a deformation part of which mechanical stiffness is decreased by receiving the thermal energy from the photo-thermal response part.
2. The device of claim 1, wherein the photo-thermal response part is a polymer film containing a light absorption heating element.
3. The device of claim 1, wherein the deformation part contains a physical properties-controllable polymer.
4. The device of claim 1, wherein: the cell region comprises a plurality of cell regions arranged two-dimensionally, the light source part includes a plurality of light source parts respectively provided on the plurality of cell regions, and from a plan view, the flexible layer vertically overlaps the plurality of cell regions.
5. The device of claim 4, further comprising: a support part configured to support the flexible layer, wherein, from a plan view, the support part surrounds the plurality of cell regions.
6. The device of claim 1, wherein the pressure control unit comprises: a pipe configured to communicate with an inside of the chamber, and a pump configured to adjust an internal pressure of the chamber by being connected to the pipe.
7. The device of claim 1, wherein the pressure control unit comprises: a heating electrode between the light source part and the flexible layer, and a volatile layer on the heating electrode.
8. The device of claim 7, wherein the heating electrode is heated by a Joule heating method to emit thermal energy.
9. The device of claim 7, wherein the heating electrode comprises a patterned metal.
10. The device of claim 7, wherein the heating electrode has a thickness of about 100 nm to about 1 m.
11. An operation method of a shape-variable electronic device comprising a light source part, a flexible layer on the light source part, a chamber between the light source part and the flexible layer, and a pressure control unit that controls an internal pressure of the chamber, the flexible layer including a photo-thermal response part and a deformation part, the method comprising: emitting light from the light source part to the photo-thermal response part, the photo-thermal response part generating thermal energy when receiving the light; heating the deformation part using the thermal energy, the deformation part being heated to decrease mechanical stiffness of the deformation part; and changing a shape of the deformation part by increasing the internal pressure with the pressure control unit.
12. The method of claim 11, wherein a shape of the flexible layer on a region not irradiated with light from the light source part does not change.
13. The method of claim 11, wherein the photo-thermal response part is a polymer film containing a light absorption heating element.
14. The method of claim 11, wherein the deformation part contains a physical properties-controllable polymer.
15. The method of claim 11, wherein the pressure control unit comprises: a pipe configured to communicate with an inside of the chamber, and a pump configured to adjust an internal pressure of the chamber by being connected to the pipe.
16. The method of claim 11, wherein the pressure control unit comprises: a heating electrode between the light source part and the flexible layer, and a volatile layer on the heating electrode.
17. The method of claim 16, wherein the heating electrode is heated by a Joule heating method to emit thermal energy.
18. The method of claim 16, wherein the heating electrode includes a patterned metal.
19. The method of claim 16, wherein the heating electrode has a thickness of about 100 nm to about 1 m.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The accompanying drawings are included to provide a further understanding of the inventive concept, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the inventive concept and, together with the description, serve to explain principles of the inventive concept. In the drawings:
[0010]
[0011]
[0012]
[0013]
[0014]
[0015]
[0016]
[0017]
[0018]
[0019]
[0020]
DETAILED DESCRIPTION
[0021] In order to fully understand the configuration and effects of an embodiment of the inventive concept, preferred embodiments of the inventive concept will be described with reference to the accompanying drawings. However, the embodiment of the inventive concept is not limited to the embodiments disclosed below, but may be implemented in various forms and various changes may be made thereto. However, the embodiment of the inventive concept is provided to make the disclosure of the embodiment of the inventive concept complete through the description of the embodiments and to fully inform those skilled in the art of the embodiment of the inventive concept of the scope of the invention.
[0022] In this specification, when a component is mentioned as being on another component, it means that the component may be formed directly on the other component or a third component may be interposed between them. In addition, in the drawings, the thickness of components is exaggerated for effective explanation of technical content. Portions indicated with the same reference numerals throughout the specification indicate the same components.
[0023] In various embodiments of this specification, terms such as first, second, and third are used to describe various components, but these components should not be limited by these terms. These terms are merely used to distinguish one component from another. Embodiments described and illustrated herein also include complementary embodiments thereof.
[0024] The terms used in this specification are for describing embodiments and are not intended to limit the embodiment of the inventive concept. In this specification, a singular form includes a plural form unless specifically stated otherwise in the context. The component referred to in terms comprises and/or comprising as used in the specification do not preclude the existence or addition of one or more other components.
[0025] A shape-variable electronic device of the embodiment of the inventive concept may include various electronic devices having a flexible layer of which shape changes. Hereinafter, a shape-variable display as an example of the shape-variable electronic device according to embodiments of the inventive concept will be described in detail.
[0026]
[0027] Referring to
[0028] As an example, the light source part 101 may include one light-emitting device (e.g., LED). As another example, the light source part 101 may include a plurality of light emitting elements (e.g., a plurality of micro LEDs).
[0029] A surrounding support part 104 may be provided on the substrate 103. A flexible layer 105 supported by the support part SUP may be provided on the cell region 102. From a plan view, the support part SUP may surround the flexible layer 105. The flexible layer 105 may be spaced apart from the light source part 101 in a vertical direction (i.e., a third direction D3) by the support part 104. The flexible layer 105 may include a plurality of stacked layers. Each of the plurality of layers constituting the flexible layer 105 may be made of a flexible material so that its shape may be deformed. The flexible layer 105 may include a photo-thermal response part 202 and a deformation part 201.
[0030] The photo-thermal response part 202 may contain a photo-thermal material capable of absorbing light (e.g., visible light or infrared light) and emitting heat. For example, the photo-thermal response part 202 may contain PEDOT (poly(3,4-ethylenedioxythiophene)), PEDOT:PSS (poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate)) or PEDOT/Metallic particle composite. As another example, the photo-thermal response part 202 may contain carbon-elastomer composite (e.g., Graphene nanoplatelet/elastomer composite). The photo-thermal response part 202 may have elasticity, which is the property of being deformed when receiving force from the outside and returning to its original shape when the force is removed.
[0031] The deformation part 201 may include a dielectric polymer layer having bistable characteristics whose mechanical property changes depending on temperature. Since the deformation part 201 has bistable characteristics, it has high mechanical stiffness at room temperature, but the mechanical stiffness thereof may be rapidly lowered at a specific temperature or more. That is, at room temperature, the deformation part 201 may become rigid, and at a specific temperature or more, the deformation part 201 may be flexible.
[0032] The term mechanical stiffness used in the embodiment of the inventive concept may be a value obtained by measuring resistance to deformation of the shape of the deformation part 201. For example, referring to
[0033] If the pressure 208 acts in the third direction D3 and no deformation occurs in the deformation part 201, the protruding distance 209 is about 0, and therefore the value of the mechanical stiffness of the deformation part 201 in this case may be very large, approaching infinity.
[0034] If the pressure 208 acts in the third direction D3 and thus the deformation part 201 is bent in the third direction D3, the protruding distance 209 may have a specific value. The value of mechanical stiffness in this case may be significantly decreased compared to the case where the protruding distance 209 described above is about 0.
[0035] The deformation part 201 may contain a shape memory polymer. For example, the shape memory polymer may be selected from the group consisting of PTBA (poly(tert-butyl acrylate)), tert-butyl acrylate copolymer, and stearyl acrylate polymer.
[0036] A chamber 203 between the light source part 101 and the flexible layer 105, and a pressure control unit that adjusts the internal pressure of the chamber 203 may be provided.
[0037] Referring to
[0038] Referring to
[0039] Therefore, at room temperature, the liquid state is maintained and no increase in pressure occurs, but when the heating electrode 303 is heated and releases thermal energy 304, the liquid material may evaporate into a gaseous state 305, and the internal pressure of the chamber 203 may increase. The heating electrode 303 may be heated by a Joule heating method, which has a high heating rate.
[0040] Since light LIG emitted from the light source unit 101 should reach a local region of the photo-thermal response part 202, it is not preferable that the heating electrode 303 located between the light source unit 101 and the photo-thermal response part 202 reflects or absorbs light.
[0041] Therefore, as the heating electrode 303, a patterned metal that allows light to be transmitted without reducing the intensity of light 306 may be used. The shape of the pattern is not limited to one. Referring to
[0042] In addition, as the heating electrode 303, an electrode of which thermal conductivity is excellent and which has a nanometer thickness may be used so as to have high light transmittance in the visible and near-infrared regions. The thickness of the heating electrode 303 may be about 100 nm to about 1 m, for example, about 100 nm to about 700 nm, about 300 nm to about 700 nm, or about 300 nm to about 500 nm.
[0043]
[0044] Referring to
[0045] The temperature of the deformation part 201 may rise due to the delivered thermal energy 304. As the temperature of the deformation part 201 rises to a specific temperature or more, the mechanical stiffness of the deformation part 201 may be lowered. The mechanical stiffness of the deformation part 201 may be lowered in proportion to the thermal energy 304 delivered to the deformation part 201. In other words, as the thermal energy 304 delivered to the deformation unit 201 increases, the deformation part 201, which is made rigid, may be more flexibly changed.
[0046] Referring to
[0047] Referring to
[0048] Referring to
[0049] As described above, the mechanical stiffness of the deformation part 201 may be adjusted by adjusting the intensity of the light 306 emitted from the light source part 101. If the mechanical stiffness varies, the degree of change when applying the same pressure 208 may vary. Therefore, even if the magnitude of the pressure 208 applied to the chamber is not adjusted, the degree of protrusion 209 of the protruding region 210 may be precisely adjusted by adjusting the intensity of the light 306.
[0050] Referring to
[0051] A method for returning the shape-variable display to the initial state illustrated in
[0052]
[0053] Referring to
[0054] Light source units 101 may be respectively provided on the cell regions 102. As an example, the light source parts 101 may have the same size and shape. As another example, the light source parts 101 may have different sizes and shapes.
[0055] The support part 104 may be provided on the substrate 103. From a plan view, the support part 104 may surround the plurality of cell regions 102. That is, one support part 104 may define a plurality of cell regions 102.
[0056] One flexible layer 105 may be provided on the plurality of cell regions 102. The flexible layer 105 may be provided on the plurality of cell regions 102 and may extend in the horizontal directions (i.e., first direction D1 and second direction D2) across the plurality of cell regions 102. From a plan view, the flexible layer 105 may overlap the plurality of cell regions 102 and the plurality of light source parts 101.
[0057] The flexible layer 105 may be spaced apart from the light source parts 101 in the third direction D3 by the support part 104. The flexible layer 105 may include the photo-thermal response part 202 and the deformation part 201 that are sequentially stacked.
[0058] Referring to
[0059] As previously described with reference to
[0060] Meanwhile, since the flexible layer 105 on the second cell region CEL2 is in a rigid state, the shape of the flexible layer 105 may not change even when pressure is applied. Accordingly, a protruding region may not be formed on the second cell region CEL2.
[0061] Referring to
[0062] Therefore, when the same pressure is applied, the degree of deformation of the flexible layer 105 on the third cell region CEL3 may be greater than the degree of deformation of the flexible layer 105 on the first cell region CEL1. That is, the second protruding region 214 formed in the flexible layer 105 on the third cell region CEL3 may be formed to be higher in the D3 direction than the first protruding region 212 formed in the flexible layer 105 on the first cell region CEL1.
[0063] As described above, if the temperature of the flexible layer 105 is lowered to a specific temperature or less after the flexible layer 105 is deformed by pressure, the flexible layer 105 may become rigid while maintaining its deformed shape. Accordingly, even if pressure is no longer applied, the flexible layer 105 may maintain the deformed shape as it is.
[0064] After the flexible layer 105 is solidified into the deformed shape, pressure may be applied again and light may be emitted from some of the light source parts 101. In this case, in a state where the deformed shape of the flexible layer 105 is maintained, the mechanical stiffness of only the flexible layer 105 on the cell regions 102 including the light source part 101 that emits light may be decreased. For example, after solidifying the flexible layer 105 in the form illustrated in
[0065] The flexible layer 105 on the first cell region CEL1 of which mechanical stiffness is decreased, that is, flexibility is increased, may be deformed when force is applied from the outside of the flexible layer 105. As the intensity of light emitted from the light source part 101 on the first cell region CEL1 becomes stronger, the mechanical stiffness of the flexible layer 105 on the first cell region CEL1 is lowered, and thus the degree of deformation thereof may be increased when force is applied from the outside. That is, the texture of the flexible layer 105 felt outside the flexible layer 105 may vary depending on the intensity of light emitted from the light source part 101.
[0066] Furthermore, the warmth felt outside the flexible layer 105 on the first cell region CEL1 may vary depending on the intensity of light emitted from the light source part 101 on the first cell region CEL1. As the intensity of light emitted from the light source part 101 on the first cell region CEL1 becomes stronger, the magnitude of thermal energy emitted from the photo-thermal response part 202 on the first cell region CEL1 may increase. Therefore, the temperature felt outside the flexible layer 105 on the first cell region CEL1 may be high.
[0067] In this way, by controlling the on/off of each light source part 101, the warmth and texture of the flexible layer 105 may be locally adjusted.
[0068] In the shape-variable electronic device according to an embodiment of the inventive concept, a plurality of supports SUP are provided on the substrate SUB to surround each cell region CEL in a single grid form. In this case, since the support part SUP in the form of a partition wall is disposed between adjacent cell regions CEL, deformation may be independently applied on a cell-by-cell basis. For example, through precise deformation on a cell-by-cell basis, information for various purposes, such as three-dimensional shapes, characters, Braille, and UI, may be three-dimensionally expressed and delivered.
[0069] In a shape-variable electronic device according to another embodiment of the inventive concept, one flexible layer 105 supported by one support part 104 may be disposed on the plurality of cell regions 102. In other words, there may be no support part 104 in the form of the partition wall between adjacent cell regions 102. Since the support part 104 is reduced, an area of the shape-changing device may be decreased, and the expression a three-dimensional shape having a curved form, and a micro-surface structure may be possible.
[0070] The method of expressing the three-dimensional shape having the curved form and the micro-surface structure will be described with reference to
[0071] Referring to
[0072] Referring to
[0073] Referring to
[0074] Referring to
[0075] Although the embodiments of the inventive concept have been described with reference to the accompanying drawings, those of ordinary skill in the art to which the embodiment of the inventive concept pertains will understand that the embodiment of the inventive concept may be implemented in other specific forms without changing its technical idea or essential features. Therefore, it should be understood that the embodiments described above are illustrative and not restrictive in all respects.
[0076] The shape-variable electronic device according to an embodiment of the inventive concept may have a compact structure and may implement various shapes, warmth, and texture.
[0077] Although the embodiments of the present invention have been described, it is understood that the present invention should not be limited to these embodiments but various changes and modifications can be made by one ordinary skilled in the art within the spirit and scope of the present invention as hereinafter claimed.