OPTICAL UNIT FOR INSPECTION, INSPECTION EQUIPMENT COMPRISING THE OPTICAL UNIT AND INSPECTION METHOD

摘要

There is provided a general-purpose optical unit for inspection capable of reducing its space. The optical unit (1) projects a predetermined pattern as an inspection object arranged at a predetermined position, to a lens module (102). The optical unit (1) comprises a patterned chart (12), a light source (11) for irradiating the chart (12) from the back of the chart (12) viewed from a lens module (100), and an object distance conversion lens (3) provided between the chart (12) and an objective lens (101). The object distance conversion lens (3) emits each light beam LF of the same group from the chart (12) radially in such a manner that the light from the chart (12) is converted into light equal to remote light, emits each light beam LF of the same group in such a manner that the main light beam ML thereof is converged, and the chart (12) is arranged closer to the lens module (100) than the predetermined position.