Performance model of depth from defocus with an unconventional camera.

In this paper, we present a generic performance model able to evaluate the accuracy of depth estimation using depth from defocus (DFD). This model only requires the sensor point spread function at a given depth to evaluate the theoretical accuracy of depth estimation. Hence, it can be used for any (un)conventional system, using either one or several images. This model is validated experimentally on two unconventional DFD cameras, using either a coded aperture or a lens with chromatic aberration. Then, we use the proposed model for the end-to-end design of a 3D camera using an unconventional lens with chromatic aberration, for the specific use-case of small unmanned aerial vehicle navigation.

Turning a conventional camera into a 3D camera with an add-on.

We propose to add an optical component in front of a conventional camera to improve depth estimation performance of depth from defocus (DFD), an approach based on the relation between defocus blur and depth. The add-on overcomes ambiguity and the dead zone, which are the fundamental limitations of DFD with a conventional camera, by adding an optical aberration to the whole system that makes the blur unambiguous and measurable for each depth. We look into two optical components: the first one adds astigmatism and the other one chromatic aberration. In both cases, we present the principle of the add-on and experimental validations on real prototypes.