Pocket comparator



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.