Electro-optical measuring system using precision light translator

摘要

An electro-optical measuring system wherein a scanning laser or light beam is precisely translated in a direction parallel to itself at a constant rate to define a time-varying sensing field whose energy is picked up by a photoelectric detector that yields an output signal. An object whose dimension is to be measured is inserted in the field whereby the output signal of the detector takes the form of a pulse whose leading edge is developed by the traversal of the beam across one boundary of the object, thereby blocking passage of the energy to the detector, and whose trailing edge is developed by the traversal of the beam across the opposite boundary of the object to restore the energy pick-up. The width or time duration of the pulse is an exact index to the distance between these boundaries, the time duration being converted into a measurement reading. Scanning of the beam is effected by combining two or more optical scanner means whose individual non-linearities are of such magnitude and form that in combination these non-linearities are effectively cancelled out and a final scan is achieved that is extremely linear, whereby measurements of exceptional accuracy are obtained.