Radiation Model of a Housing of Cooled Infrared Detector Array

The infrared camera detects infrared radiation from the observed objects, Its main element is the array of infrared detectors, which converts the received radiation into an electrical signal. The radiation sources recorded by the detector can be divided as useful, received from the observed scene, and useless received from such objects as the detector housing and lens elements. These unusable radiation sources have a significant impact on the design of the detector itself. The article presents a model of the detector housing and a quantitative analysis of the influence of various radiation sources on the effectiveness of radiation detection from the observed scene.

The heat leakage measurement of dewars for infrared detector arrays

Consideration is given to the analysis of a number of implementation of calorimetry method of infrared detector array dewar’s heat leakage measurements. The heat leakage measurements were made both with and without nitrogen vapor heat capacity consideration. The heat exchange process between nitrogen vapor and Dewar’s well walls was analyzed. The most reliable results were achieved by means of approach with calibration.

Simultaneous-integrated evaluation of mechanical–thermal sensory attributes of woven fabrics in considering practical wearing states

Tactile sensations of fabrics are the primary property determining the wearing comfort of clothing; however, comprehensive evaluation of the fabric tactile property by considering the flexural buckling of fabrics under high curvature, hysteresis performance and thermal property has not been fully studied, leading to a clear gap between the existing measurement methods and application requirements. Herein, a simultaneous-integrated testing method, namely the Touch Sensation Tester for Fabrics (TST-F) was introduced to evaluate the mechanical–thermal sensory properties of woven fabrics. The introduced instrument used one device with a single mechanical sensor to test various mechanical properties by constructing different deformations of fabrics, and the thermal property was simultaneously measured using an infrared detector array, achieving an efficient characterization of the mechanical–thermal sensation properties of textiles. The measurement capacity and repeatability of the TST-F were statistically analyzed; the measurement indices and their relation with fabric mechanical–thermal sensation properties were also exhibited. Results showed that the TST-F was promising to characterize fabric touch sensations in terms of bending stiffness, compression softness with wrinkling, stretching tightness and thermal comfort by considering the infrared transmission and heat conductivity of textiles.

Non-dispersive infrared multi-gas sensing via nanoantenna integrated narrowband detectors

Non-dispersive infrared (NDIR) spectroscopy analyzes the concentration of target gases based on their characteristic infrared absorption. In conventional NDIR gas sensors, an infrared detector has to pair with a bandpass filter to select the target gas. However, multiplexed NDIR gas sensing requires multiple pairs of bandpass filters and detectors, which makes the sensor bulky and expensive. Here, we propose a multiplexed NDIR gas sensing platform consisting of a narrowband infrared detector array as read-out. By integrating plasmonic metamaterial absorbers with pyroelectric detectors at the pixel level, the detectors exhibit spectrally tunable and narrowband photoresponses, circumventing the need for separate bandpass filter arrays. We demonstrate the sensing of H2S, CH4, CO2, CO, NO, CH2O, NO2, SO2. The detection limits of common gases such as CH4, CO2, and CO are 63 ppm, 2 ppm, and 11 ppm, respectively. We also demonstrate the deduction of the concentrations of two target gases in a mixture.