Scanning of workpieces such as lumber cants

摘要: An array camera used to scan elongated workpieces moving through a measuring zone transversely their lengths has its photoresponsive detector elements aligned lengthwise of the workpieces, with optical axes lying in common plane intersecting zone. Each element "sees" only small (e.g., 8×8 mm) pixel. Radiation sources are located at opposite sides said and emit radiation towards be reflected from workpieces. During each succession short cycles 4 millisecond duration) is exposed successively originating source exclusion other, thus produce an A output B during cycle, also substantially low level R output. For least certain subtracted outputs same for ΔA ΔB difference signals. Timing such that signals cycle originate one surface area on workpiece, therefore inclination ascertainable as function values. fourth interval detect laser beam oblique workpiece surface, then L From particular outputs, local thickness ascertainable.