All spectrometers rely on some mechanism to achieve spectral selectivity; common examples include gratings, prisms, and interferometers with moving mirrors. A spectroscopic technique—here dubbed Planck spectroscopy—that measures the spectral emissivity of a surface using only a temperature-controlled stage and a detector, without any wavelength-selective optical components is experimentally demonstrated and validated. Planck spectroscopy involves the measurement of temperature-dependent thermally emitted power, where the spectral selectivity is realized via the temperature and wavelength dependence of Planck's law. Planck spectroscopy in the mid infrared, for wavelengths from 3 to 13 µm—limited primarily by the bandwidth of the detector—with resolution of ≈1 µm is experimentally demonstrated and validated. The minimalistic setup of Planck spectroscopy can be implemented using infrared cameras to achieve low-cost infrared hyperspectral imaging and imaging ellipsometry.

中文翻译：

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普朗克光谱

所有光谱仪都依赖某种机制来实现光谱选择性；常见的例子包括光栅、棱镜和带有移动反射镜的干涉仪。一种光谱技术——这里被称为普朗克光谱——仅使用温度控制平台和检测器测量表面的光谱发射率，没有任何波长选择性光学组件，经过实验证明和验证。普朗克光谱涉及测量与温度相关的热发射功率，其中光谱选择性是通过普朗克定律的温度和波长依赖性来实现的。中红外普朗克光谱对于 3 到 13 µm 的波长（主要受探测器带宽的限制）具有 ≈1 µm 的分辨率已通过实验证明和验证。