Abstract: A spectral imaging system includes an objective lens system, an optical splitter, a dispersion system, and an optical combiner. The optical splitter is arranged to be in an optical path of an object being imaged through the objective lens system to provide an imaging optical path and a spectrometer optical path. The dispersion system is arranged in the spectrometer optical path. The optical combiner is arranged in the imaging optical path and a path of dispersed light from the dispersion system to combined dispersed light with a corresponding optical image of the object.

Abstract: An additive manufacturing apparatus includes a laser and a detection system. The laser emits a laser beam to heat a powder bed to form a melt pool, and the melt pool emits light proportional to a temperature of the melt pool. The detection system includes a spectral disperser and one of a) two or more on-axis sensors or b) a line scanner. The two or more on-axis sensors or the line scanner are/is located along an axis of the emitted light, the detection system receives the emitted light from the melt pool, and an intensity of the emitted light detected by the a) two or more on-axis sensors or the b) line scanner is compared with a blackbody spectral map at a particular wavelength of the emitted light to determine a temperature of the melt pool.