High transmission optical inspection tools

摘要

Techniques for increasing the percentage of light that is transmitted through optical inspection systems that operate in or near the ultraviolet and deep ultraviolet electromagnetic spectrums are described. Along with increasing the amount of light transmission, the techniques of the present invention also provide additional advantages such as reduction of ripple, increased ability to match inspection systems, and improving manufacturability. The techniques of the present invention involve using an auto-focus light source near the operational range of the inspection system and slightly raising the lower end of the operational range.