Pelican Imaging has released a set of re-focusable pictures taken with its light field camera for smartphones. Light field technology is back in the headlines, following Lytro's latest offering, the Illum. Pelican Imaging, though, is taking a slightly different approach from Lytro: instead of placing an array of microlenses between the sensor and the main lens, Pelican uses an array of main lenses - each with a sensor behind it. And while the idea of a multi-camera array is not particularly new (a Stanford research group* previously developed something similar), this is the first time we're seeing the technology miniaturized for a smartphone.

With control over focus, perspective, aperture, and the ability to tilt or rotate the focal plane, light field imaging expands the set of creative opportunities available to a photographer. Pelican Imaging's sample photos demonstrate not only the re-focusing ability of their multi-camera module, but also the ability to focus on multiple subjects, change the depth-of-field, and shift perspective to a limited degree. Have a look at an example below:

One of Pelican Imaging's light field photographs, focused on the front-most subject. Pelican Imaging's light field photograph, with extended depth-of-field. [Source: Pelican Imaging]

Pelican Imaging's use of an array of small cameras is more suited to the flat and wide surface of a smartphone than one big sensor and lens, which requires more depth. An array of small lenses and sensors together provide a much larger than usual combined sensor size. And while the camera array is rather small in this iteration of Pelican Imaging's technology (see below), one could imagine a larger array for a higher-end device. Furthermore, this arrangement is still likely to have less depth than a comparable single sensor/lens light field camera would require. 

Pelican Imaging's multi-camera array in a smartphone. [Source: Pelican Imaging]

What might light field bring to smartphone photography? For one, it can offer more control over depth-of-field than conventional smartphone cameras. The light field provides a depth map of the scene, which can be used to render shallower depth-of-field images and improve subject isolation.

Furthermore, Pelican Imaging claims that no pre-focus is required at all to take a picture, promising faster picture-taking. That said, this approach leaves a finite range of objects that can be brought into perfect focus for any light field camera (that is, there's a limited depth of re-focusability). This becomes more and more of an issue with the inherent shallower depth-of-field afforded by larger sensors, requiring one to pre-focus to ensure that subjects of interest fall within the re-focusable range. It's possible that in this particular, smaller-sensor iteration of Pelican Imaging's technology, focus is limited to a pre-set region (e.g. near, or just short of, the hyperfocal distance). For now, though, the example in the rollover above suggests that a good range of focus distances are supported.

'It captures photos and videos the same way your eyes do... with depth.' - CEO Chris Pickett

It's interesting to note that the light field data captured by this multi-camera array has applications beyond re-focusing, choosing which subjects in your image are in sharp focus, or changing depth-of-field. As Pelican Imaging CEO Chris Pickett explains in the video below, a light field camera 'captures photos and videos the same way your eyes do... with depth'. The resulting depth map can aid in extracting objects out of, and inserting objects into, scenes. It can also be used for 3D modeling and printing applications, 3D viewing, and augmented reality. The brief video overview of Pelican Imaging's technology takes a look at some of these concepts and effects:

*The same group, in fact, that Lytro Founder Ren Ng collaborated with for his light field dissertation research.