A pocket comparator is an optical device for measuring and inspection comprising a loupe and a reticle. The instrument was developed and manufactured by the Bell & Howell Company, but similar instruments of other names are made by other manufacturers.
It is used for:
Linear measurements in fractions of an inch Circular measurements in fractions of an inch Radius measurements Angle measurements Narrow line width measurements Circular measurements in decimals of an inch Linear measurements in inches Linear measurements in millimeters Measurements are performed by bringing the surface of the reticle as close as possible to the work inspected.
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