3D Imaging from Passive Scattered Light Using Plenoptic Information

Abstract

We use plenoptic measurements of visible, infrared, and THz radiation to locate and image objects that are hidden from direct view by detecting their passive radiation scattered from rough surfaces.

Maximizing the non-line-of-sight information content retrievable from passive scattered light fields: a comparison between visible, long wave infrared, and terahertz radiation

“…However, these methods require high-power THz light sources, which increases the complexity of the instrumentation and may reveal an attempt to detect hidden objects. By contrast, in our previous work [16,[24][25][26], we proposed detecting the passive THz radiation generated by black body radiation, where we experimentally determined that many construction walls act as mirrored surfaces. In this work, we have successfully demonstrated passive THz imaging and location estimation of a NLOS human subject and human-temperature objects.…”

“…Several previous authors [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] have developed passive methods for the aforementioned purpose using visible radiation. However, the performance of these methods is often compromised by the significant scattering produced by the rough surface of the wall and the visible ambient light.…”

“…However, the performance of these methods is often compromised by the significant scattering produced by the rough surface of the wall and the visible ambient light. We and several authors have reported that the use of long-wave-infrared (LWIR) light has several advantages that can reduce these difficulties [16,[17][18][19][20]. First, thermally-elevated objects such as human subjects are seen as light emitters, and these signals stand out amongst the ambient background.…”