A differential interference contrast module designed for video imaging is available from Navitar Inc. When used with one of the company’s high-magnification lenses (zoom or nonzoom), it enables users to image a microscopy sample to a video monitor. With the device, they can view a 3-D representation of the surface geometry of a sample, if raised and lowered regions can be distinguished. The technique is enhanced with the use of transmitted light on reflective surfaces. It is suitable for inspecting diamonds, optical media, flat panel displays, semiconductor wafers and translucent biological samples.