The pioneering ultraviolet-visible spectrohotometer launched by Beckman Instruments in 1941. Like many early spectrophotometers, this was a point by point instrument and could not record a continuous spectrum. Nonetheless its ruggedness, relative cheapness and ease of use ensured its popularity in the 1940s and 1950s. A spectrophotometer is an instrument for measuring the intensity of light in various parts of the spectrum, especially as transmitted or emitted by a substance or solution at a particular wavelength.
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