Projection-type instrument for enlarging and projecting image of small workpiece for comparative measurement, has liquid crystal display projection screen that has monitoring display to indicate workpiece profile measuring line graph

摘要

Liquid crystal display screen (1) has diffuse projection screen on surface of liquid crystal, and a monitoring display indicating a drawing for measuring the profile of workpiece (55) with preset enlargement. Monitoring display shows relative motion displacement which is detected by a displacement sensor, on the liquid crystal display screen. The optical monitoring system has a projection lens (53) for projecting image of the workpiece on a screen, relative motion unit (57) for relative motion of workpiece carrying table (56) and optical monitoring system, and displacement sensor for detecting relative displacement through the relative motion unit. Displacement sensor has linear shifting sensor for detecting displacement of table in x,y, and z directions, and also an angle sensor for detecting rotational angle of table.