Optical camouflage turns car's back seat transparent
By Ben Coxworth
November 8, 2012
When you turn around to look behind your car as you’re reversing, what do you see? If your car is like most, you see a bit of the road through the back window, with a whole lot of your back seat underneath. If only you could see through that seat, you could see so much more of the road. Well, a group from Japan’s Keio University has developed a system that lets drivers do that ... sort of.
The experimental system incorporates rearview video cameras mounted on the back of the car, that are linked to a projector mounted behind and below the front seats. That unit projects a composite image of the cameras’ combined video output onto a rear-facing half-mirror, mounted above it and near the driver. That half-mirror – which the driver can see through when they look back in its direction – reflects the projected video onto the back seat.
The end result is that when the driver turns their head back, they can see both the actual view out the rear window, and a video continuation of that view projected onto the back seat. In other words, they can see more of what’s behind them, as if the back seat wasn’t there. An onboard computer figures out the size at which the video should be projected, in order to properly achieve the “transparent back seat” illusion.
Of course, the video output from the cameras could simply be displayed on a dashboard screen, as is already the case with conventional rearview video systems. According to the creator of the system, Prof. Masahiko Inami, the advantage of his technology is that it gives a sense of depth that a simple video screen doesn’t – it presumably also feels more natural for drivers, as it allows them to see what’s behind them by looking behind them.
Although the system is currently set up to make only the back seat “transparent,” Inami plans to develop the technology to the point that the entire interior of the car could be seen through, providing the driver with 360-degree visibility. He hopes to have a commercial version of the system ready for use within about five years.
A demonstration of the technology can be seen in the DigInfo video below.