

This video camera is powered by light - praba230890
http://www.cs.columbia.edu/CAVE/projects/self_powered_camera/

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grogenaut
That's the elegant solution I love about welding equipment. They realized hrm
super bright light source.... lets use solar cells. Need just enough power in
battery form to keep the micro alive. Been doing it since way back in the
'90s.

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ctdonath
As we go increasingly wireless, we become keenly aware of recharging
batteries. Consequence is greater interest in "ambient power harvesting". A
device powered by its own sensor's energy input is insightful. What next?
keyboards powered by typing? trackpad/mouse by clicking & movement? Screens
with an extra sub-pixel for light collection? Smart watch "self-winding"?

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pjc50
Backlit screens and backlit watches are never going to be self-powered. It's
more feasible that a passive e-paper like display could be self-powered.

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mfisher87
Depends on how you define the phrase "self-powered." Today, an "electric-
powered" car may not necessarily mean to the exclusion of gasoline as an
additional power source.

If a backlit device harvests the unused light from its own backlight, it would
surely be powered by itself. Not _purely_, but it would be harvesting its own
outputs for energy.

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MrBra
Unused light? What did you mean by that?

Fueling an electric car with gasoline has has nothing to do with self powered
ambient harvesting machines. It looks like you're just trying to stretch
concepts to suit your initial arguments.

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mfisher87
I apologize for not responding sooner.

LCD displays operate by partially blocking or completely blocking the
backlight to produce an image. The blocked backlight photons are not used to
generate the image. As opposed to a CRT or OLED display, which generate light
to produce an image.

What original argument? This is my only comment on this thread. My point was
that "X-powered" does not mean "powered-solely-by-X."

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njharman
Combine this with the recent millimeter scale computer motes
[http://robotics.eecs.berkeley.edu/~pister/SmartDust/](http://robotics.eecs.berkeley.edu/~pister/SmartDust/)
and we get real close to several sci-fi themes such as optical camouflage and
universal panopticon.

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abecedarius
What happened to make
[http://robotics.eecs.berkeley.edu/~pister/SmartDust/in2010](http://robotics.eecs.berkeley.edu/~pister/SmartDust/in2010)
so wildly off? Did those projections seem realistic 10 years before? Is it
just taking a little longer?

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Globz
This is very interesting!

"it could lead to a fully self-powered solid-state image sensor that produces
a useful resolution and framerate"

In this case would it be able to output colors?

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danbruc
Color just means putting red, green and red filters in front of the pixels in
some pattern and so it is definitely not a principle problem but you will lose
a large part of the light spectrum for every pixel and therefore harvest a lot
less energy.

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indrax
In theory, you could put the filters on for just a fraction of the time to
measure the colors, and spend most of the time collecting all the light. I'm
not sure how to do that and stay low power.

You could have separate smaller color sensing pixels, using only a fraction of
the surface area.

ETA: There are also transparent solar panels which only absorb UV. If that
were tuned for visible colors, you could have three transparent layers over an
ordinary panel, and maybe not lose anything.

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amelius
Can it also be used to power other electronics attached to it, such as a CPU?

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dang
URL changed from [http://www.engadget.com/2015/04/15/self-powered-
camera/](http://www.engadget.com/2015/04/15/self-powered-camera/), which
points to this.

