# US 2021/0333162 A1 · Stretchable strain sensors and devices > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0333162 A1 - Document ID: US20210333162A1 - Status: Published application - Kind: A1 - Application number: 17/104,549 - Filed: 2020-11-25 - Published: 2021-10-28 - Earliest claimed: 2020-04-24 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Gae Hwang LEE; Youngjun YUN - Web page: https://patentgrep.com/patent/US20210333162A1 ## CPC - G01L 1/241: {by photoelastic stress analysis} - H10K 50/115: comprising active inorganic nanostructures, e.g. luminescent quantum dots - H10K 50/125: specially adapted for multicolour light emission, e.g. for emitting white light - H10K 59/876: {comprising a resonant cavity structure, e.g. Bragg reflector pair} - H10K 77/111: {Flexible substrates} - Y02E 10/549: Organic PV cells - G01L: MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE (weighing G01G) - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract A stretchable strain sensor may exhibit wavelength selectivity according to a thickness change of a thickness of the stretchable strain sensor, in a thickness direction extending parallel to the thickness of the stretchable strain sensor, due to elongation of the stretchable strain sensor in an elongation direction extending perpendicular to the thickness direction. The stretchable strain sensor may have an emission spectrum that changes according to strain variation of a strain on the stretchable strain sensor. ## Claims ### Claim 1 A stretchable strain sensor, the stretchable strain sensor configured to exhibit wavelength selectivity according to a thickness change of a thickness of the stretchable strain sensor, in a thickness direction extending parallel to the thickness of the stretchable strain sensor, due to elongation of the stretchable strain sensor in an elongation direction extending perpendicular to the thickness direction. ### Claim 2 (depends on 1) The stretchable strain sensor of claim 1, wherein: the stretchable strain sensor comprises an optoelectronic device, and the optoelectronic device is configured to display one or more colors according to the thickness change of the thickness of the stretchable strain sensor in the thickness direction due to elongation of the stretchable strain sensor in the elongation direction. ### Claim 3 (depends on 2) The stretchable strain sensor of claim 2, wherein the optoelectronic device is configured to display a color of a first wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at a first elongation rate, the optoelectronic device is configured to display a color of a second wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at a second elongation rate, the second wavelength spectrum being different from the first wavelength spectrum, the second elongation rate being higher than the first elongation rate, and the optoelectronic device is configured to display a color of a third wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at a third elongation rate, the third wavelength spectrum being different from the first wavelength spectrum and the second wavelength spectrum, the third elongation rate being higher than the second elongation rate. ### Claim 4 (depends on 3) The stretchable strain sensor of claim 3, wherein the second wavelength spectrum is a shorter wavelength spectrum than the first wavelength spectrum, and the third wavelength spectrum is a shorter wavelength spectrum than the second wavelength spectrum. ### Claim 5 (depends on 2) The stretchable strain sensor of claim 2, wherein the optoelectronic device is configured to not display a color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is below a threshold elongation rate, and the optoelectronic device is configured to display the color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is at or above the threshold elongation rate. ### Claim 6 (depends on 2) The stretchable strain sensor of claim 2, wherein the optoelectronic device is configured to display a color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is below a threshold elongation rate, and the optoelectronic device is configured to not display the color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is at or above the threshold elongation rate. ### Claim 7 (depends on 2) The stretchable strain sensor of claim 2, wherein the optoelectronic device is configured to display a color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is within a range between a first threshold elongation rate and a second threshold elongation rate, and the optoelectronic device is configured to not display the color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is outside the range between the first threshold elongation rate and the second threshold elongation rate, so as to be below the first threshold elongation rate or above the second threshold elongation rate. ### Claim 8 (depends on 2) The stretchable strain sensor of claim 2, wherein the optoelectronic device includes a first electrode including a reflective layer, a second electrode facing the first electrode, the second electrode being spaced apart from the reflective layer by an optical path length, and a light emitting layer between the first electrode and the second electrode. ### Claim 9 (depends on 8) The stretchable strain sensor of claim 8, wherein as a rate of the elongation increases, the optical path length is shorter, and the optoelectronic device is configured to display a color of a wavelength spectrum corresponding to the optical path length according to a change in the optical path length. ### Claim 10 (depends on 9) The stretchable strain sensor of claim 9, wherein the light emitting layer is configured to emit white light, and the optoelectronic device is configured to display a color of a portion of a visible light spectrum. ### Claim 11 (depends on 10) The stretchable strain sensor of claim 10, wherein the optoelectronic device is configured to display a color of a first wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at a first elongation rate, the optoelectronic device is configured to display a color of a second wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at a second elongation rate, the second wavelength spectrum being a shorter wavelength region than the first wavelength spectrum, the second elongation rate being higher than the first elongation rate, and the optoelectronic device is configured to display a color of a third wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at a third elongation rate, the third wavelength spectrum being a shorter wavelength region than the second wavelength spectrum, the third elongation rate being higher than the second elongation rate. ### Claim 12 (depends on 9) The stretchable strain sensor of claim 9, wherein the light emitting layer is configured to emit light of one wavelength spectrum of a red wavelength spectrum, a green wavelength spectrum, or a blue wavelength spectrum, and the optoelectronic device is configured to not display a color corresponding to the one wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is below a threshold elongation rate, and the optoelectronic device is configured to display the color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is at or above the threshold elongation rate. ### Claim 13 (depends on 9) The stretchable strain sensor of claim 9, wherein the light emitting layer is configured to emit light of one wavelength spectrum of a red wavelength spectrum, a green wavelength spectrum, or a blue wavelength spectrum, and the optoelectronic device is configured to display a color corresponding to the one wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is below a threshold elongation rate, the optoelectronic device is configured to not display the color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is at or above the threshold elongation rate. ### Claim 14 (depends on 9) The stretchable strain sensor of claim 9, wherein the light emitting layer is configured to emit light of one wavelength spectrum of a red wavelength spectrum, a green wavelength spectrum, or a blue wavelength spectrum, and the optoelectronic device is configured to display a color corresponding to the one wavelength spectrum in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is within a range between a first threshold elongation rate and a second threshold elongation rate, and the optoelectronic device is configured to not display the color in response to the stretchable strain sensor being elongated in the elongation direction at an elongation rate that is outside the range between the first threshold elongation rate and the second threshold elongation rate, so as to be either below the first threshold elongation rate or above the second threshold elongation rate. ### Claim 15 (depends on 8) The stretchable strain sensor of claim 8, wherein the second electrode is a semi-transmissive electrode. ### Claim 16 (depends on 8) The stretchable strain sensor of claim 8, wherein each of the first electrode and the second electrode is a stretchable electrode. ### Claim 17 (depends on 2) The stretchable strain sensor of claim 2, further comprising: a stretchable substrate configured to structurally support the optoelectronic device. ### Claim 18 (depends on 17) The stretchable strain sensor of claim 17, wherein the stretchable substrate includes a first region having a first elastic modulus and a second region adjacent to the first region and having a second elastic modulus, the second elastic modulus being lower than the first region, and the optoelectronic device is in the first region. ### Claim 19 A stretchable strain sensor, the stretchable strain sensor configured to have an emission spectrum that changes according to strain variation of a strain on the stretchable strain sensor. ### Claim 20 (depends on 19) The stretchable strain sensor of claim 19, wherein the stretchable strain sensor includes an optoelectronic device, and the optoelectronic device includes a first electrode including a reflective layer, a second electrode facing the first electrode, the second electrode being spaced apart from the reflective layer by an optical path length, and a light emitting layer between the first electrode and the second electrode. ### Claim 21 (depends on 20) The stretchable strain sensor of claim 20, wherein the light emitting layer is configured to emit white light, and the optoelectronic device is configured to display a color of a first wavelength spectrum in response to the stretchable strain sensor being elongated at a first elongation rate, the optoelectronic device is configured to display a color of a second wavelength spectrum in response to the stretchable strain sensor being elongated at a second elongation rate, the second wavelength spectrum being a shorter wavelength spectrum than the first wavelength spectrum, the second elongation rate being higher than the first elongation rate, the optoelectronic device is configured to display a color of a third wavelength spectrum in response to the stretchable strain sensor being elongated at a third elongation rate, the third wavelength spectrum being a shorter wavelength spectrum than the second wavelength spectrum, the third elongation rate being higher than the second elongation rate, and the first wavelength spectrum, the second wavelength spectrum, and the third wavelength spectrum are within a visible wavelength spectrum. ### Claim 22 (depends on 20) The stretchable strain sensor of claim 20, wherein the light emitting layer is configured to emit light of one wavelength spectrum of a red wavelength spectrum, a green wavelength spectrum, or a blue wavelength spectrum, the optoelectronic device is configured to not display a color corresponding to the one wavelength spectrum in response to the stretchable strain sensor being elongated at an elongation rate that is below a threshold elongation rate, and the optoelectronic device is configured to display the color in response to the stretchable strain sensor being elongated at an elongation rate that is at or above the threshold elongation rate. ### Claim 23 (depends on 20) The stretchable strain sensor of claim 20, wherein the light emitting layer is configured to emit light of one wavelength spectrum of a red wavelength spectrum, a green wavelength spectrum, or a blue wavelength spectrum, the optoelectronic device is configured to display a color corresponding to one wavelength spectrum in response to the stretchable strain sensor being elongated at an elongation rate that is below a threshold elongation rate, and the optoelectronic device is configured to not display the color in response to the stretchable strain sensor being elongated at an elongation rate that is at or above the threshold elongation rate. ### Claim 24 (depends on 20) The stretchable strain sensor of claim 20, wherein the light emitting layer is configured to emit light of one wavelength spectrum of a red wavelength spectrum, a green wavelength spectrum, or a blue wavelength spectrum, the optoelectronic device is configured to display a color corresponding to the one wavelength spectrum in response to the stretchable strain sensor being elongated at an elongation rate that is within a range between a first threshold elongation rate and a second threshold elongation rate, and the optoelectronic device is configured to not display the color in response to the stretchable strain sensor being elongated at an elongation rate that is outside the range between the first threshold elongation rate and the second threshold elongation rate, so as to be either below the first threshold elongation rate or above the second threshold elongation rate. ### Claim 25 (depends on 1) A device comprising the stretchable strain sensor of claim 1. ### Claim 26 (depends on 19) A device comprising the stretchable strain sensor of claim 19.