Laser camera peers around corners

Using ordinary walls, doors or floors as reflective surfaces, MIT researchers have created a camera that produces recognizable 3-D images from outside the camera’s line of sight. Describing his team’s work in the journal Nature Communications, lead researcher Ramesh Raskar said the system uses a femtosecond laser, which emits bursts of light so short that their duration is measured in quadrillionths of a second.

To peer into a room that’s outside its line of sight, the camera might fire femtosecond bursts of laser light at the wall opposite the doorway. The light would reflect off the wall and into the room, then bounce around and re-emerge, ultimately striking a detector that can take measurements every few picoseconds, or trillionths of a second. Because the light bursts are so short, the system can gauge how far they’ve traveled by measuring the time it takes them to reach the detector.

The system performs this procedure several times, bouncing light off several different spots on the wall, so that it enters the room at several different angles. The detector, too, measures the returning light at different angles. By comparing the times at which returning light strikes different parts of the detector, the system can piece together a picture of the room’s geometry and contents.

The brain-bending work of turning the raw data into an image is performed by algorithms that Raskar developed in collaboration with Andreas Velten, formerly at the MIT Media Lab; Otkrist Gupta, a graduate student in Raskar’s group; Thomas Willwacher, a mathematics postdoc at Harvard University; and Ashok Veeraraghavan, an assistant professor of computer science at Rice University.

“Four years ago, when I talked to people in ultrafast optics about using femtosecond lasers for room-sized scenes, they said it was totally ridiculous,” crowed Raskar, who is keen to enhance the system further. Future versions of the system, he believes, could be used by emergency responders – firefighters looking for people in burning buildings or police determining whether rooms are safe to enter – or by vehicle navigation systems, which could bounce light off the ground to look around blind corners. It could also be used with endoscopic medical devices, to produce images of previously obscure regions of the human body.

Related:
Discuss this article in our forum
Watch a video about the camera
Depth-of-field irrelevant with omni-focus camera
Cheap-and-cheerful pinhead camera doesn’t need lens
Single Pixel Camera Snaps High-Res Images

Source: Massachusetts Institute of Technology

, ,

Comments are closed.

1957 Press Photo Business Men Workers Outside Debris Boards Brick Vintage Image picture

1957 Press Photo Business Men Workers Outside Debris Boards Brick Vintage Image

$18.88



RC remote radio controlled control TOY BUMPER CAR speed vehicle by SHARPER IMAGE picture

RC remote radio controlled control TOY BUMPER CAR speed vehicle by SHARPER IMAGE

$24.95



Spread (2014) Image - #20, Outside, Justin Jordan/Felipe Sobreiro, VF/NM picture

Spread (2014) Image - #20, Outside, Justin Jordan/Felipe Sobreiro, VF/NM

$1.79



Merry Christmas Santa Claus Neon Sign Lights Custom Bar LED Holiday Decor 24

Merry Christmas Santa Claus Neon Sign Lights Custom Bar LED Holiday Decor 24"

$228.00



1985 Marvel Comic Images Spider-Man Black Suit Venom Outside Window T-Shirt picture

1985 Marvel Comic Images Spider-Man Black Suit Venom Outside Window T-Shirt

$699.99



1961 Photo Refrigerator Stove Outside Window Drawers Kitchen Vintage Image picture

1961 Photo Refrigerator Stove Outside Window Drawers Kitchen Vintage Image

$18.88



1942 Photo Shooting Range Outside Palm Trees Targets Grass Vintage Image picture

1942 Photo Shooting Range Outside Palm Trees Targets Grass Vintage Image

$18.88



1932 Photo Crowd People American Flags Banners Outside Street Vintage Image picture

1932 Photo Crowd People American Flags Banners Outside Street Vintage Image

$18.88



F000859 Photo of family outside house with well and bucket. c1900s. Image shot 1 picture

F000859 Photo of family outside house with well and bucket. c1900s. Image shot 1

$4.74



Custom Merry Christmas Neon Sign Light Bar Wall Decor Happy New Year Lights 27

Custom Merry Christmas Neon Sign Light Bar Wall Decor Happy New Year Lights 27"

$242.00



Powered by WordPress. Designed by WooThemes