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Photodetectors operating across the short‐, mid‐, and long‐wave infrared (SWIR–LWIR, λ = 1–14 µm) underpin modern science, technology, and society in profound ways. Narrow bandgap semiconductors that form the basis for these devices require complex manufacturing, high costs, cooling, and lack compatibility with silicon electronics, attributes that remain prohibitive for their widespread usage and the development of emerging technologies. Here, a photoconductive detector, fabricated using a solution‐processed narrow bandgap conjugated polymer is demonstrated that enables charge carrier generation in the infrared and ultrasensitive SWIR–LWIR photodetection at room temperature. Devices demonstrate an ultralow electronic noise that enables outstanding performance from a simple, monolithic device enabling a high detectivity (D*, the figure of merit for detector sensitivity) >2.44 × 109 Jones (cm Hz1/2 W−1) using the ultralow flux of a blackbody that mirrors the background emission of objects. These attributes, ease of fabrication, low dark current characteristics, and highly sensitive operation overcome major limitations inherent within modern narrow–bandgap semiconductors, demonstrate practical utility, and suggest that uncooled detectivities superior to many inorganic devices can be achieved at high operating temperatures. [ABSTRACT FROM AUTHOR]

Inspired by nacre that is mechanically strong and versatile in light manipulation, large‐scale black films with a nacre‐like microstructure and carbon nanotube inclusion were prepared using a facile self‐assembly technique. A layered structure promoting blackness and toughness simultaneously was realized, affording robust films with a solar–absorptivity as high as 96.9%. Our design strategy and fabrication process will be beneficial for the facile access to various advanced blackbody coatings. [ABSTRACT FROM AUTHOR]

Fengyun-2 (FY-2) are the first-generation geostationary meteorological satellites (GEOMS) in China, two of which, FY-2E and FY-2G, are the operating workforce to support the dual-satellite observation mode. The on-board blackbody preliminarily used for stability monitoring of the instrument's radiometric response was equipped behind its fore-optics due to the technical limitations in the 1990s with what was referred to as an internal-blackbody (IBB) and operated at a unique pre-set temperature. In this article, a novel IBB calibration (IBBC) approach is proposed and the radiometric contributions of the main optical elements as well as the IBB itself are modelled and extracted. This is the most distinguishing difference from the traditional full-path blackbody calibration. The IBBC software has been in service for more than 2 years. Compared with the high spectral resolution reference instruments recommended by the Global Space-based Inter-Calibration System, the monthly mean calibration biases of the long-wave infrared band (IR1: 10.8 µm) and water vapour band (IR3: 6.95 µm) are shown to be lower than 1.5 K for FY-2E and lower than 1.0 K for FY-2G (for ∼90% of cases). In particular, the annual mean biases for the FY-2G IR3 band can maintain a good state of 0.4 K, which is nearly identical to that of other high-class in-orbit satellites, e.g. MTSAT-2 and MSG-1. Likely impacted by ice contamination, the calibration biases of the long-wave split-window infrared band (IR2: 12 µm) of FY-2G could be as large as −2.3 K and similar phenomena once occurred in GOES-13 and MSG-1. This is expected to improve in the near future. In general, the calibration accuracies of FY-2G IR1 and IR3 bands have become lower than 1 K, which is significantly superior to those of other first-generation GEOMS, such as GMS-5, Meteosat-7 and GOES 4-7, whose calibration accuracies are around 2-3 K. The quality of the data could be greatly enhanced so as to benefit the global observation system. [ABSTRACT FROM AUTHOR]

Recently, a line of minimum tint in chromaticity space for sources of illumination of different correlated color temperatures (CCTs) from 2700 K to 6500 K has been reported. This line of minimum tint did not correspond to the line of blackbody radiation implicitly associated with sources of white illumination used in architectural applications. It was noted that chromaticities along the line of minimum tint were not metamers but, rather, should represent, for a given CCT, chromaticities where the neural signals from the two spectral opponent channels were minimized. Earlier work provided a theoretical framework for representing the four unique hues where the neural signals from one spectral opponent channel are minimized. This framework was used here to quantitatively represent the line of minimum tint and then to empirically test whether this representation could predict the amount of tint perceived in six different sources of "white" Illumination." Based on these results, a provisional model is proposed for describing the tint and the amount of tint perceived in "white" Illumination used in architectural applications. [ABSTRACT FROM AUTHOR]

The transient changes in the temperature of a solid material heated by radiation were obtained by numerical calculations using an unsteady one-dimensional (1-D) energy equation. The radiative loss of heat from the surface of a heated solid increases with an increase in the radiation flux. Therefore, the net blackbody radiation into a semi-infinite solid keeps a higher proportion of the initial flux at a lower dimensionless initial flux I0(0)/αk(Tb - T0). In the case of bidirectional radiation to a finite solid, the relatively homogeneous heating can be accomplished at the optical thickness αL ≅ 100). The heating rate is very low at αL ≲ 10-1 resulting from the absorption of a small part of the radiation energy. On the other hand, the heating rate is high at αL ≳ 10¹, but the heating is limited to a region near the wall, which results in an inhomogeneous temperature profile. At αL ≳ 10², the temperature profiles become identical with that obtained for αL → ∞. [ABSTRACT FROM AUTHOR]