Wiimote Project

Hardware Support => IR Pens => Topic started by: mattloto on December 07, 2008, 08:24:21 PM

Title: How to tell if pen is IR
Post by: mattloto on December 07, 2008, 08:24:21 PM
Hi guys!!!   I'm new here and i have a question.  For the IR pen, i was wondering if a laser pointer could do.  It has a LED light and a button, but idk if its IR or not.  i was wondering how i could tell if the wii mote would pick it up 
Title: Re: How to tell if pen is IR
Post by: benpaddlejones on December 07, 2008, 08:38:00 PM
mattloto
It needs to operate at 940nm (light wave length). So you won't be able to see it with your naked eye.

benpaddlejones
Title: Re: How to tell if pen is IR
Post by: mattloto on December 07, 2008, 08:48:41 PM
what about a motion sensor?  does that have IR?  Im just looking for other things to use as a IR pen cuz i cant buy a IR light
Title: Re: How to tell if pen is IR
Post by: Fopenplop on December 07, 2008, 09:23:26 PM
Actually, I was under the impression that there was a slight overlap in the wave lengths visible to the naked eye, and what the Wiimote can sense.
Title: Re: How to tell if pen is IR
Post by: benpaddlejones on December 07, 2008, 09:39:14 PM
what about a motion sensor?  does that have IR?  Im just looking for other things to use as a IR pen cuz i cant buy a IR light
Tell me where you are and I will let you know of a source. To test you can just use a candle or cigarette lighter as fire emits quite a lot of IR.

Actually, I was under the impression that there was a slight overlap in the wave lengths visible to the naked eye, and what the Wiimote can sense.
If you remove the red lense on teh front of your wiimote the IC2 Bus camera will actually track any light (must be in a dark room). The filter is quite specific to 940nm, hence why a number of users find certain IR-Leds don't work. The visble spectrum ends at about 750nm. I think the physics purists call the 750-2500nm range "near infrared" and spectrums 2500nm to radiowaves (spectrum ?) as actual infrared. You will find the video chip in most digit camera is sensitive to lower spectrum (near) infrared.

benpaddlejones :)
Title: Re: How to tell if pen is IR
Post by: UndCon on December 09, 2008, 12:51:30 AM
That is why some of us are offering cheap shipping of IRdiodes.

http://www.wiimoteproject.com/other-ir-products/vishay-tsal-6400-t1506/



what about a motion sensor?  does that have IR?  Im just looking for other things to use as a IR pen cuz i cant buy a IR light
Title: Re: How to tell if pen is IR
Post by: Wiweeyum on December 09, 2008, 06:56:41 AM
Yeah, there's some overlap into visible light. I've been using a nurses LED flashlight (used for checking eye dilation) as my IR pen while waiting for the pencentric pen to show up in the mail. The angle is terrible and it's annoying having a bright flashlight spot on my screen while pushing the button, but it's worked.

I don't know the specs of the specific LED used or I'd share. The little pen is unmarked.

Also, the reflections from my desk lamp register as dots to track screwing up the pen. I have to turn the lamp off while using the whiteboard program. Interestingly the wiimote does not track the actual light bulb, only the reflections. It's a traditional bulb, not fluorescent, with three 'touch' lighting levels.