As there were still not enough cameras in this world, the researchers created a new type both microscopic and self-powered, allowing it to roughly integrate anywhere and make it work perpetually. This is undoubtedly a cool technology, but it will probably lead to a rise in sales of aluminum foil.
Engineers have already studied the possibility of having a camera sensor turned on with the same light falling on it. After all, it is essentially two different functions of a photovoltaic cell – the one stores the energy that falls there while the other records the amount of energy that fell on it
The problem is that if you have a cell that does one thing, it can not do the other. So, if you want to have a sensor of a certain size, you have to dedicate some of that asset to the collection power, or swap the cells quickly between the two tasks.
Euisik Yoon and Postdoc Sung-Yun Park at the University of Michigan have found a solution that avoids these two problems. It turns out that photosensitive diodes are not completely opaque – in fact, a lot of light passes through them. Therefore, by placing the solar cell under the image sensor does not actually deprive it of light.
This breakthrough led to the creation of this "Simultaneous Imaging and Energy Recovery" sensor, which does what it says on the box.
The prototype sensor they built measured less than a square millimeter and is fully self-powered in the sun. He captured images up to 15 frames per second of reasonably reasonable quality:
In the paper, the researchers point out that they could easily produce better images with some adjustments to the sensor, and Park tells IEEE Spectrum that the power consumption of the chip is also not optimized – from so that it could also work at higher framerates or lower lighting levels.
In the end, the sensor could be essentially an almost invisible camera that works forever without the need for a battery or even wireless. It sounds good!
For this to be a successful spy camera, of course, it takes more than just a single imaging component – a storage and transmission medium is required for any camera to be useful. But microscopic versions of these are also under development, so assembling them is only a matter of time and effort.
The team published its work this week in the journal IEEE Electron Device Letters.