fig9

Figure 9. Application in temperature and strain sensors. (A) Temperature sensor based on the transmittance change of the LCE film due to temperature change. When the temperature is above a safety threshold, the red LED turns on and an alarm sounds to alert the users. Reproduced with permission^[150]. Copyright 2022, American Chemical Society; (B) self-sensing cantilever actuator with integrated miniature optoelectronic components. Thermal and nonthermal bending modes could be experienced, and the real-time optical intensity is measured for the monitoring of the bending deformation. Reproduced with permission^[14]. Copyright 2021, American Association for the Advancement of Science; (C) NIR light and temperature sensor based on the photothermal pyroelectric property. Reproduced with permission^[151]. Copyright 2018, The Royal Society of Chemistry; (D) LM-LCE coaxial fibers, which could sense the fiber stretching by measuring the voltage or resistance change of the inner LM. Scale bars, 2 mm at the top panel and 1 cm at the bottom. Reproduced with permission^[152]. Copyright 2021, Wiley-VCH GmbH; (E) strain sensor based on highly stretchable and highly uniform main-chain cholesteric LCE film, which could change color at different strain levels. The film is continuously blue-shifted and homogenous under a bending strain with zero Gaussian curvature. When the film is bent with nonzero Gaussian curvature, the two parts separated by a gap show different colors (e.g., red and blue). Scale bar, 1 cm. Reproduced with permission^[48]. Copyright 2022, Wiley-VCH GmbH; (F) environmental temperature and humidity sensor, showing a color change from transparent to blue to green when the humidity increases or the temperature decreases. Scale bar, 20 μm. Reproduced with permission^[49]. Copyright 2020, American Chemical Society.