Author Topic: The ambient light is very important?  (Read 3968 times)

Offline Marcela

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on: May 22, 2008, 10:38:09 AM
First excuse me, my english is not perfect but I will try to explain...

The ambient light is not good for the correct operation of the wiimote? 
I need use the wiimote whiteboard in a place with ambient light and some ligths switch on. Is possible or not?

I wait yours answers. Thanks !

Marcela.




Offline inio

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Reply #1 on: May 22, 2008, 09:01:46 PM
It depends greatly on the infrared component of the ambient light.  Fluorescent lights (including compact fluorescent lamps that replace traditional bulbs) emit almost no infrared light, so you can use them freely around Wii Remote applications.  Traditional incandescent bulbs emit some, but should be ok as long as the lamp itself (or reflections of it) isn't visible to the Wii Remote's sensor.  Light from halogen lamps or sunlight can cause significant problems, because of the extremely intense infrared content.



Offline benpaddlejones

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Reply #2 on: May 25, 2008, 07:23:14 AM
Marcela
The Wiimote specifically detects lights around 940nm (a wavelength undetectable to the human eye, which can only see light between 750nm and 350nm approx). Wavelengths below 940nm are specifically filtered by the red filter at the front of the device. You will find some hacks on youtube involving removing the filter and using the Wiimote to track other lower wavelength light sources like laser light, which work well in dark conditions but not in normal light as the ambient light will overload the tracking.

Essentially it depends on which wavelength your ambient light is emitting ???

In a classroom with some ambient sunlight and full fluorescent tubes lighting the classroom there is no effect as all light emmitt light with a wavelength well below 950nm. Thus I find the Wiimote and 940nm IR-Led works awesome.

However, if a flame, sunlight or other infrared source is present then yes this will affect the performance of your Wiimote.

You can actually test the Wiimote Interactive Whiteboard software using a cigarette lighter which emits enough Infrared light for the Wiimote to detect and track.

If you are having trouble getting the Wiimote to track you IR-Led it is more likely that your IR-Led is either under powered or lacks strength.

benpaddlejones


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