The Determining Method of Background Light Attenuation Coefficient in Discerning of High Temperature Forgings

The key of high temperature forging size measurement based on using CCD is to extract the forging contour from the complex background. According to different forging field conditions, the paper obtains the necessary and sufficient preconditions for forgings discriminated from the background by analysis on the radiation spectral character of the high temperature forgings, the reflective spectral character of the background light and the spectral response character of the color CCD. The preconditions show that only when the reflection of background light less than the radiation of the high temperature forgings can the forgings be discerned completely. This paper proposes an implementation method for size measurement. The method has the advantages of clear concept and low operation costs. It provides the theoretical basis and available way for the discrimination and size measurement of high temperature forgings based on common and special color CCD.