Abstract: A system for measuring the energy transmission through a moving aperture pattern includes a CCD (charge coupled device) sensor having at least one row of pixels arranged perpendicular to the direction of motion. An encoder responds to the motion and provides count pulses. For each count pulse, specific pixels are addressed to establish a plurality of inspection areas for the aperture pattern through which energy transmission is measured. The transmission is averaged for all the inspection areas to determine the acceptability of the aperture pattern.

Abstract: Method and apparatus are described for producing a unique machine-readable marking, such as a bar-code marking, on each of a succession of workpieces, such as glass envelope parts of cathode-ray tubes. The method comprises producing and applying a different unique stencil for each workpiece and then applying a suitable paint through the stencil.