Sometimes referred to as a UV–Vis spectrophotometer because it measured both the ultraviolet (UV) and visible spectra, the DU spectrophotometer is credited as being a truly revolutionary technology. Approximately 30,000 DU spectrophotometers were manufactured and sold between 19. Beckman's National Technical Laboratories (later Beckman Instruments) developed three in-house prototype models (A, B, C) and one limited distribution model (D) before moving to full commercial production with the DU.
This model of spectrophotometer enabled scientists to easily examine and identify a given substance based on its absorption spectrum, the pattern of light absorbed at different wavelengths. The DU spectrophotometer or Beckman DU, introduced in 1941, was the first commercially viable scientific instrument for measuring the amount of ultraviolet light absorbed by a substance. DU Spectrophotometer, National Technical Laboratories, 1947
