Quantitative thermal imaging using liquid crystals

Abstract

A detailed knowledge of surface temperatures is vitally important in many fields of science and engineering. Thermochromic liquid crystals have become widely accepted over the past decade as a simple, low-cost, and accurate tool for temperature measurement, but their potential in biological surface temperature monitoring or heat production, or biomechanics, has not been fully exploited. In this paper, the principles and practice of using liquid crystal thermography for noninvasive temperature measurement are discussed. Types of liquid crystal materials, their application to surfaces, chromatic interpretation, and associated advantages and limitations are summarized. Finally, the application of liquid crystals to particular fields of interest in biomedical engineering is reviewed and potential applications are identified. Based on this review, the suitability of using liquid crystals in medical applications is assessed.

Colorimetric Voltmeter Using Colloidal Fe3O4@SiO2 Nanoparticles as an Overpotential Alarm System for Zinc–Air Batteries

“…The most well-known color parameter is the RGB (red-green-blue) function, where a given color is described as mixture of the three primary colors of light. However, in the case of colloidal APC device, where the wavelength of the light is modulated over a large range, hue-saturation-value (HSV), color function is preferred because the color information is stored in a single parameter of the hue. − The lighting conditions may affect the saturation and value but not hue. This makes the hue in the HSV color function a reliable parameter for quantitative characterization of the colorimetric response of the device.…”