AMERSFOORT, Netherlands, Feb. 20, 2015 — A new version of the AQ6373 optical spectrum analyzer from Yokogawa Europe BV incorporates a new monochromator with a sharp passband filter edge for clearly separating spectral signals in close proximity to one another. The AQ6373B is designed for measurements in the short-wavelength region, from 350 to 1200 nm. It offers a high resolution of up to 0.01 nm in the 400- to 470-nm range, a high close-in dynamic range of up to 60 dB, and a high sensitivity to -80 dBm in the 500- to 1000-nm range. It also includes a free-space optical input, enabling the instrument to accept optical fibers with core diameters from 9 to 800 μm, and a function for determining the exact color of the input light as experienced by the average human eye sensitivity (according to the CIE 1931 XYZ standard). It features a startup time of about 2 minutes including self-calibration and takes 0.5 s to measure a 100-nm span. Wavelength calibration can be performed using the emission line of a common low-cost xenon lamp. The AQ6373B is suited to testing optical devices and systems over the visible spectrum and the first window of optical communications, and to test and characterize LEDs and lasers.