HIGH-MAGNIFICATION IMAGE-ANALYSIS WITH NOVEL BACKGROUND REFLECTANCE TECHNIQUE FOR MEASURING RESIDUAL INK IN SHEETS

Measuring the correct sizes of microscopic ink specks by image analysi s requires diffuse far-red light. At higher magnification, the field s ize diminishes. This increases the number of fields required to achiev e an acceptable level of counting confidence for the largest particles . Measuring particles 8 mu m and larger combined with the image reflec tance measurement, where the detected specks are excluded, gives the o perator the best combination of speed and statistical confidence for o ptimizing and monitoring the deinking process.