Structured light 3-D measurement module and system for illuminating an area-under-test using a fixed-pattern optic

Summary

The companion patent 8,976,367 covered fixed-pattern optics where the object’s own motion sweeps it through the phase patterns. That works on a conveyor or inside a pipe, but it doesn’t help when the geometry being measured is stationary.

For a still object the scanner still needs to sample multiple phases somehow, but giving up the fixed-pattern optic means giving up its advantages — no electronic projector, no synchronization timing, small footprint. The challenge is to keep those advantages while adding the ability to scan a stationary scene.

This patent claims a fixed-pattern projector that is mechanically swept across the scene rather than waiting for the object to move. An actuator shifts or rotates the patterned optic so that each point on a stationary surface sees the same sequence of phases that a moving part would have seen on a conveyor. The dual-frequency pattern still eliminates the need for phase unwrapping. The result is a compact area-scanning device — for dental, head-and-face, lung, or machinery surfaces — that gets full 3D coverage without the complexity of an electronically-driven projector.