| abstract |
Various embodiments include an apparatus including a phase mask and circuitry. The phase mask is configured and arranged with optics in an optical path to modify a shape of light, passed from an object. The shape modification characterizes the light as having two lobes with a lateral distance that changes along a line, having a first orientation, as a function of an axial proximity of the object to a focal plane, and with the line having a different orientation depending on whether the object is above or below the focal plane. The circuitry is configured and arranged to generate a three-dimensional image from light detected at the image plane, by using the modified shape to provide depth-based characteristics of the object. |