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Product: Cell Phone: Camera
Flash-and-Video Ranging App   (0)  [vote for, against]
High-speed vid of the flash's travel.

Center the target in your screen, and touch "Go". The flash fires an improbably-short and incredibly-bright blip, while the camera records at a frenetic frame rate. The video actually catches the reflections of the flash coming back from near objects first, then further-away ones. In slo-mo, it looks like a lantern traveling down a hallway.

The software searches for the lighting-up of the center of the screen, and calculates distance from time. There is a slide to move back and forth in the vid, and a choice of units of distance.
-- baconbrain, Mar 01 2015

Topical http://gizmodo.com/...-path-at-1681990733
High-speed video of light pulse travel. [neutrinos_shadow, Mar 02 2015]

More http://gizmodo.com/...f-a-mirr-1667133832
Light pulse bouncing. [neutrinos_shadow, Mar 02 2015]

Baked: Time-of-flight camera https://en.wikipedi...me-of-flight_camera
[notexactly, Mar 02 2015]

Yeah, I have no idea on the technology on this one. It fell out of another idea, something about triangulating on target, in the unrestful A.M.

I am sure it could be made to work, even if only for retro-reflectors in the distant dark. Tweaking the flash to a recognizable series of blips is all else that I have.

You think just detecting the pulse in the center pixels is all that is needed? (It would have to ignore the flash going off, of course.) It doesn't have to actually record vid - that was left over from trying to not point at the target, plus I want to see a light pulse travel.

(It was something about two innocent-seeming tourists directing mortar fire, I think.)
-- baconbrain, Mar 02 2015


Consider the high speed recordings of bullet impacts and the technique involved, then consider how that could be done around 800,000 times faster. Hell, even 80,000 times faster. That is the challenge you are proposing.
-- WcW, Mar 02 2015


Thanks.

I know nothing about CCDs. Except maybe the name means "charge- coupled device".

When I studied electronics, TVs still had tubes. I don't mean picture tubes, I mean the clear, glowy things with all the funny metal bits in, that, like, bounced the electrons or something.
-- baconbrain, Mar 02 2015


Baked, many times over, by many companies, since about 15 years ago—see my link.

It does require special hardware, but it's getting cheaper all the time and will be in smartphones in a few years. (The LG G3 actually has a single time-of-flight sensor (not a ToF camera) for focusing the camera for close-up photos.)

Also, look at Ramesh Raskar's work in the computational photography field. (You might remember the "1 million fps" camera—that was him and his team. (It wasn't actually 1 million fps; it used stroboscopy to synthesize that framerate.) There was a popular demo video of that device that showed light traveling along a water bottle in slow motion, which is the same concept.)
-- notexactly, Mar 02 2015



random, halfbakery