The world’s first self-powered video camera that runs without a battery and can deliver a picture every second has been developed via researchers drove by an Indian-origin scientist.
To develop the prototype cam, researchers designed a pixel that can not only measure incident light but also convert the incident light into electric power.
“We are in the middle of a digital imaging revolution,” said Shree K Nayar, TC Chang Professor of Computer Science at the Columbia University, who led the study.
He noted that in the most recent year alone, approximately two billion cams of different sorts were sold around the world.
“I think we have quite recently seen the tip of the iceberg. Digital imaging is expected to enable many emerging fields including wearable gadgets, sensor systems, smart environments, personalised medicine, and the Internet of Things.
“A cam that can work as an untethered gadget forever – with no outer power supply – would be incredibly useful,” said Nayar.
Nayar understood that although digital cams and soalr panels 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 digital cam is an image sensor, a chip with millions of pixels. The key enabling gadget in a pixel is the photodiode, which produces an electric current when exposed to light.
This mechanism enables every pixel to measure the intensity of light falling on it.
Nayar and partners used off-the-shelf parts to create a image sensor with 30×40 pixels.
In his model cam, which is housed in a 3D printed body, each pixel’s photodiode is always operated in the photovoltaic mode.
The pixel configuration is very simple, and uses only two transistors.
During every picture capture cycle, the pixels are used first to record and read out the picture and after that to harvest energy and charge the sensor’s power supply – the image sensor continuously toggles between image capture and power harvesting modes.
At the point when the cam is not used to capture images, it can be used to produce power for different gadgets, for example, a telephone or a watch.
Nayar noted that the image sensor could used a rechargeable battery and charge it through its harvesting capability.
“A couple of different designs for image sensors that can harvest energy have been proposed before. However, our prototype is the first demonstration of a completely self-powered camera,” Nayar included.