Coded-aperture broadband light field imaging using digital micromirror devices

Coded-aperture light field (CALF) imaging can record four-dimensional information of incident light rays with a high angular resolution while retaining a camera’s full pixel count. However, existing systems are limited by either imaging speeds and image contrasts of liquid-crystal spatial light modulators or by severe dispersion to broadband light of digital micromirror devices (DMDs), both of which hinder CALF’s widespread applications. Here, we overcome these limitations by developing dispersion-eliminated (DE) CALF imaging. Using a dual-DMD design to compensate for dispersion in the entire visible spectrum, the DECALF imaging system captures <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>1280</mml:mn> </mml:mrow> </mml:mrow> <mml:mo>×</mml:mo> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>1024</mml:mn> </mml:mrow> </mml:mrow> <mml:mo>×</mml:mo> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>5</mml:mn> </mml:mrow> </mml:mrow> <mml:mo>×</mml:mo> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>5</mml:mn> </mml:mrow> </mml:mrow> </mml:math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mo stretchy="false">(</mml:mo> <mml:mi>x</mml:mi> <mml:mo>,</mml:mo> <mml:mi>y</mml:mi> <mml:mo>,</mml:mo> <mml:mi>θ</mml:mi> <mml:mo>,</mml:mo> <mml:mi>φ</mml:mi> <mml:mo stretchy="false">)</mml:mo> </mml:math> color light field images at 20 Hz. Using static and dynamic three-dimensional (3D) color scenes, we experimentally demonstrate multi-perspective viewing, digital refocusing, and 3D tracking of the DECALF imaging system. We also apply it to the imaging and analyses of escape behaviors of freely moving normal and disease-model zebrafish.