Light field geometry of a standard plenoptic camera

The Standard Plenoptic Camera (SPC) is an innovation in
photography, allowing for acquiring two-dimensional images focused at
different depths, from a single exposure. Contrary to conventional cameras,
the SPC consists of a micro lens array and a main lens projecting virtual
lenses into object space. For the first time, the present research provides an
approach to estimate the distance and depth of refocused images extracted
from captures obtained by an SPC. Furthermore, estimates for the position
and baseline of virtual lenses which correspond to an equivalent camera
array are derived. On the basis of paraxial approximation, a ray tracing
model employing linear equations has been developed and implemented
using Matlab. The optics simulation tool Zemax is utilized for validation
purposes. By designing a realistic SPC, experiments demonstrate that a
predicted image refocusing distance at 3.5 m deviates by less than 11%
from the simulation in Zemax, whereas baseline estimations indicate no
significant difference. Applying the proposed methodology will enable an
alternative to the traditional depth map acquisition by disparity analysis.