An On-Line Spectrophotometer for Collection and Manipulation of Absorbance Spectra

Abstract

A uv-visible recording spectrophotometer has been developed which uses an on-line general purpose digital computer and the optical train of a conventional double beam recording spectrophotometer. The computer controls all functions of the instrument and permits the collection and manipulation of high quality absorption spectra without the use of electronic or optical correction devices. Spectra are represented by a series of up to 500 individual data points. Spectra can be manipulated in a variety of ways to meet particular experimental situations and can be displayed or plotted on an arbitrary absorbance scale. A spectrum can be added to, or substracted from, any other spectrum, differentiated, converted to log absorbance, or multiplied by an arbitrary factor. Data can be preserved on paper tape or presented graphically as a high quality labeled plot of variable size on either a wave-length or a wave number scale. The complete system can scan a full spectrum at a maximum rate of 30 nm/sec over any part of a range from 230 to 700 nm. Details of the system are presented with examples of its performance.