The system of infrared width gauge with dual-linear CCD,based on digital signal processor(DSP) is introduced.The system adopts the three-level pipeline structure:optical acquisition of the CCD sensor,data acquisition of analog-to-digital converter(ADC) and the data procession of DSP.According to the relationship between the exposure time and the output analog voltage of CCD,the gain of CCD is regulated by the DSP chip automatically.So the signal is kept from distorting,and the accuracy is increased.The dual-linear CCD method based on the stereoscopic vision principle can eliminate the influence of weaving,hopping and tilting of the strip.In a word,under the condition of no back lighting,both high speed and high accuracy of measuring the width of wide strip can be achieved.