Double Beam UV-Visible Spectrophotometer LB-20DBS is a compact, tabletop, double beam and Czerny-Turner monochromator comprised Double Beam UV-Visible Spectrophotometer, comes with 20 mm of focal length and 1600 lines/mm of grating. With 190 to 1100 nm of wavelength range, features adjustable 5-speed bandwidth of 0.5 nm, 1 nm, 2 nm, 4 nm, and 5 nm with fast-medium-slow scanning speed. Designed with Silicon Photocell detector, deuterium and tungsten lamp as light source, and 8-inch color touch-screen, supports spectra printing, storage and data analysis. Incorporated with USB communication port, ARM chip control and data processing, and easy user interface, this spectrophotometer has automatic scanning of measured spectrum, multi-wavelength (1-3 λ) measurement, kinetic measurement, 1-3 curve fitting, and 1-4 derivative spectra.