NBS Technical Note, Issue 245

adjustment amplifier application arrangement bandwidth bound books calibration camera cathode cathode-ray tube Census changes character charge pattern Class 2 systems components considerably constructed cost dark current deflecting means dependent diameter distortion document scanning drift dynode effective aperture electron beam Electronic Scanners element factor film flying spot focussing forms FOSDIC machines function high-speed hopper iconoscope illumination Image Defects image dissector image orthicon image section instability kinescope lens light level Light Transfer Characteristic manual manufacturers mark sensing marking guides maximum ment microfilm mirror moving Nipkow disk non-uniformity Optical Character Recognition original document scanner overall paper handler parameters phosphor photo-cathode photo-emissive surface photoconductive photomultiplier phototube pick-up device pick-up tubes printing problems processing reduced registration resolution response result scanning aperture scanning beam scanning position scene scheme sensitivity Serial Scan signal signal-to signal-to-noise ratio slewing rate specifications speed stability target techniques television pick-ups vacuum vidicon voltage