Depth from Defocus

The result below shows an example of using structured light to determine distance from the camera. Unlike normal structured light, we measure how the pattern goes out of focus with distance. The advantage of this method is the camera and projector can all be on the same optical axis and not offset.

Birch, P. M., Alastair Buchanan, Rupert Young, and Chris Chatwin. 2011. “Depth from Structured Defocus That Is Independent of the Object Reflectivity Function.” Optics Letters 36 (12): 2194.