chayut350d
Very nice pen, I'm a big fan of the shrink wrap too, gives a nice fell and grip to the pen.

I did some extensive research on the Osram IR-Leds what I found was:
- Some are quoted as +-80 degree (160 degree) viewing angle by the sellers, when they are actally an 80 degree (+-40) viewing angle when you read the datasheet.
- Quite heavily dispersed over the wide VA and have poor tracking at distance
- Gives of a really wide spectrum of IR, with an average of 940nm, of which not much is actaully in the 940nm bandwidth
- Very expensive
- Easily under powered 2x AAA will quickly drop voltage to 2v
- They need 2x batteries adds to the weight and size of the IR-Pen

I'm keen for your expereince on the tracking at distance etc. If you have very positive results i might ned to re-research.

Ben :-)