Wiimote Project

Hardware Support => IR Pens => Topic started by: echohtp on May 08, 2010, 11:49:02 PM

Title: multiple blobs from one led.
Post by: echohtp on May 08, 2010, 11:49:02 PM
so im having a bit of a problem, i made me a ir pen, from one of those little led keychains, swapped out the leds :D

the led is something unknown from a tv remote, the wiimote sees the led which is good, but its registering multiple blobs in very close proximity.

i dont have another wiimote to check thats its just the wiimote i currenty have (Borrowed it from my little cousin).

anyone have any ideas why this would be, other than a problem with the wiimote?

thanks anyone whos still active around here.
Title: Re: multiple blobs from one led.
Post by: boonjin on May 09, 2010, 12:56:46 AM
Hi,

The IR LED from the TV remote most probably will not be sufficient for good tracking with the Wiimote as the wavelength may not be optimal for the Wiimote. It is recommended to use a high-powered IR LED with wavelength of 940nm such as the Vishay TSAL 6400.

In close proximity, there is indeed a high tendency that the Wiimote will register multiple IR blobs. Most probably this is caused by refraction and reflection within the Wiimote or in the proximity of the IR LED itself. Therefore, maybe it is not feasible to directly shine the IR directly to the Wiimote at a very close proximity. However, from my experience the detection of the IR blob should be accurate at a distance of about more than 30cm.

In short, I would recommend you to get an IR LED that is known to be working and place the Wiimote further away.

Regards,
Boon Jin

Title: Re: multiple blobs from one led.
Post by: benpaddlejones on May 15, 2010, 11:29:11 PM
echohtp

Yes this is common in low quality or incorrect IR-Leds, suggest you read this: http://www.wiimoteproject.com/ir-pens/electronics-101-sharing-my-mistakes!-***-updated-***/ to help you on your way.

benpaddlejones :)