O Spectrometer is a high-performance multi-purpose spectrometer launched by Thunder Optics. It adopts several breakthrough technologies. The O Spectrometer uses a 2048-pixel high-sensitivity linear CMOS from Hamamtsu (S11639) and can be adapted to testing in the 200-1100nm wavelength. Internal structure of a grating spectrometer: Light comes from left side and diffracts on the upper middle reflective grating. The. A spectrometer (/ spɛkˈtrɒmɪtər /) is a scientific instrument used to separate and measure spectral components of a physical phenomenon. An OSA trace displays power in the vertical scale and the wavelength in the horizontal scale.