Engineering team invents a camera that powers itself

April 15, 2015, Columbia University School of Engineering and Applied Science
A video camera based on a self-powered image sensor can run indefinitely without an external power supply. Credit: Computer Vision Laboratory, Columbia Engineering

A research team led by Shree K. Nayar, T.C. Chang Professor of Computer Science at Columbia Engineering, has invented a prototype video camera that is the first to be fully self-powered—it can produce an image each second, indefinitely, of a well-lit indoor scene. They designed a pixel that can not only measure incident light but also convert the incident light into electric power. The team is presenting its work at the International Conference on Computational Photography at Rice University in Houston, April 24 to 26.

"We are in the middle of a digital imaging revolution," says Nayar, who directs the Computer Vision Laboratory at Columbia Engineering. He notes that in the last year alone, approximately two billion cameras of various types were sold worldwide. "I think we have just seen the tip of the iceberg. Digital imaging is expected to enable many emerging fields including wearable devices, sensor networks, smart environments, personalized medicine, and the Internet of Things. A camera that can function as an untethered device forever—without any external supply—would be incredibly useful."

A leading researcher in computational imaging, Nayar realized that although digital cameras and have different purposes - one measures light while the other converts light to power - both are constructed from essentially the same components. At the heart of any is an , a chip with millions of pixels. The key enabling device in a pixel is the photodiode, which produces an electric current when exposed to light. This mechanism enables each pixel to measure the intensity of light falling on it. The same photodiode is also used in solar panels to convert to . The photodiode in a camera pixel is used in the photoconductive mode, while in a solar cell it is used in the photovoltaic model.

Nayar, working with research engineer Daniel Sims BS'14 and consultant Mikhail Fridberg of ADSP Consulting, used off-the-shelf components to fabricate an image sensor with 30x40 pixels. In his prototype camera, which is housed in a 3D printed body, each pixel's photodiode is always operated in the photovoltaic mode.

A team led by Shree K. Nayar, Computer Science Professor at Columbia Engineering, has invented a prototype video camera that is the first to be fully self-powered -- it can produce an image each second, indefinitely, of a well-lit indoor scene. They designed a pixel that can not only measure incident light but also convert the incident light into electric power. Credit: Computer Vision Laboratory, Columbia Engineering

The pixel design is very simple, and uses just two transistors. During each image capture cycle, the pixels are used first to record and read out the image and then to harvest energy and charge the sensor's power supply—the image sensor continuously toggles between image capture and power harvesting modes. When the is not used to capture images, it can be used to generate power for other devices, such as a phone or a watch.

An image sensor that can capture images and harvest energy, enabling it to run indefinitely without a battery. Credit: Computer Vision Laboratory, Columbia Engineering

Nayar notes that the image sensor could use a rechargeable battery and charge it via its harvesting capability: "But we took an extreme approach to demonstrate that the sensor is indeed truly self-powered and used just a capacitor to store the harvested energy."

"A few different designs for image sensors that can harvest energy have been proposed in the past. However, our prototype is the first demonstration of a fully self-powered ," he continues. "And, even though we've used off-the-shelf components to demonstrate our design, our sensor architecture easily lends itself to a compact solid-state imaging chip. We believe our results are a significant step forward in developing an entirely new generation of cameras that can function for a very long duration—ideally, forever—without being externally powered."

Explore further: A compact image sensor providing image quality on par with larger sensors

More information: www.cs.columbia.edu/CAVE/proje … self_powered_camera/

Related Stories

3-D, after-the-fact focus image sensors invented

April 3, 2012

(PhysOrg.com) -- At the heart of digital photography is a chip called an image sensor that captures a map of the intensity of the light as it comes through the lens and converts it to an electronic signal.

An ultrasensitive molybdenum-based image sensor

June 12, 2013

A new material has the potential to improve the sensitivity of photographic image sensors by a factor of five. In 2011, an EPFL team led by Andras Kis discovered the amazing semi-conducting properties of molybdenite (MoS2), ...

Camera chip provides superfine 3-D resolution

April 3, 2015

Imagine you need to have an almost exact copy of an object. Now imagine that you can just pull your smartphone out of your pocket, take a snapshot with its integrated 3-D imager, send it to your 3-D printer, and within minutes ...

Recommended for you

Pushing lithium ion batteries to the next performance level

December 13, 2018

Conventional lithium ion batteries, such as those widely used in smartphones and notebooks, have reached performance limits. Materials chemist Freddy Kleitz from the Faculty of Chemistry of the University of Vienna and international ...

Uber filed paperwork for IPO: report

December 8, 2018

Ride-share company Uber quietly filed paperwork this week for its initial public offering, the Wall Street Journal reported late Friday.

3 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

betterexists
4 / 5 (1) Apr 15, 2015
Put a pack of them together and network them so that you never miss NOTHING!
Eikka
3.5 / 5 (2) Apr 15, 2015
our sensor architecture easily lends itself to a compact solid-state imaging chip


But can the sensor collect enough energy when you miniaturize it to a tiny chip?
rgw
not rated yet Apr 19, 2015
Put a pack of them together and network them so that you never miss NOTHING!


Other than grammar lessons....(;>)

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.