When I play Wii on my projector, setting up the sensor bar is a real pain, the cables aren't long enough and at the distance I play, the pointing is unreliable.
I considered making a longer sensor bar and fixing it to the wall but aesthetically it put me off.
I recently saw a really great project by spritetm
, he made a sensor bar using power leds and a fresnel lens to project the ir spots needed for the wiimote pointer. I made my own version to use with my projector.
I didn't have enough room to use a fresnel lens, but i did have some small aspheric lenses that would be suitable.
I used two 2.2W Osram Golden Dragon 940nm leds, they need decent heatsinking to be run a full power so I soldered them to some copper and screwed them to an alu heatsink for good thermal contact.
Then I made a frame for the lenses from sheet styrene and polystyrene cement
Eventually I had something to hold the lens and led the correct distance apart, and tested for focus.
I used an IR-modded webcam with the exposure stepped down to adjust the focus:
At 4 metres, the IR spot is about 15cm in diameter and the Wii sensitivity needed to be set at 4 or 5 to be reliable.
It's all powered by a switch-mode current driver controlled by a signal from the original sensor bar wire so that it all turns on/off with the wii. The case is from an old inverter for some ccfl lights that broke.
Everything sits on top of my projector and works really great, the pointer is nice and centred in the screen and it's much better than before when I had the sensor bar balanced on a chair and was always tripping over the wire