Minamo Touch Screen Interface on Water Surface

2008

Water, Water Tank, Webcam, Light, LCD, Mac

What is Minamo?

It is difficult to say that the interface of mechanical materials like a keyboard , a mouse and so on is very suitable for man.
So I made the Minamo interface.
"Minamo" means "Surface of water" in Japanese.
Water is the most intimate material for human body.
And I decided to make a touch screen interface on water surface.

Mechanism

This interface is composed of four elements.

1.LCD upward put on desk
2.Water tank put on LCD
3.Webcam that takes a picture of surface of the water from the lower side
4.Light that shines on finger that appears under surface of the water

The webcam takes a picture of the surface of the water from the lower side.
At this time, only when the finger has invaded water, the finger will be seen from the camera because total reflection is caused under the surface of the water.

Color tracking system on Max/MSP+Jitter finds coordinates where the finger appears and produce the cursor move and click.
Distortion of image because of taking a picture from diagonal are adjusted by affine transformation.

Notes

In this system, not only xy coordinates but also the depth of the finger can be detected.
It can be use as a 3D interface.
And I am trying to make the multi touch Minamo interface by Wii Remote now.