Hydrogen atoms in a discharge lamp emit a series of lines in the visible part of the spectrum. This series is called the Balmer series which continues into the ultraviolet range. Rydberg generalized the Balmer’s formula in terms of wave numbers to describe wavelengths of spectral lines of many chemical elements. For hydrogen the Balmer’s formula becomes a special case of Rydberg’s formula This spectrophotometer is used to measure the transmission spectra and spectrum of lines, continuous spectra of white light. The spectral range of the spectrophotometer is 350-900nm with transmission accuracy 0.1%. It is delivered with software 2m-optical fibre etc.