Application of Pulse-Width Modulation to stray light correction in spectrophotometer

In order to correct the effects of stray light on spectrophotometer in real time, a method based on Pulse-Width Modulation (PWM) was proposed, which makes up for the deficiency of traditional instruments under the variation of interference source and improves the rapid deployment capability in the wild. A system verifying to underlie the method was designed. Compared with commercial instruments under the interference of different light sources, the experimental results show that the method successfully corrected the error caused by stray light and improved the accuracy and stability of the measurement. At the same time, the convenient and sensitive technique offers great prospect for simple and cost-effective absorptive analysis instruments of stray light correction.