Dave , i am guessing that the IR leds that able to give from 1000mw/sr - 2300mw/sr cant be driven by the pic output directly and need a a nice Mosfet to sink the current , which i am guessing would sink about 100ma - 200ma.

Any recomended favorite N ch Mosfets suitable

i would guess be 20 -50v BVDSS , tdly on = <50ns or less , tdlyoff = <100ns , Ftime <50ns ,Ron <1ohm , current drain cont =>1000mA , Pulsed >4000mA

Also will i need a pull down Resistor of say 10K to ground on the gate or can the PIC internal pull down be enough ???

Cheers

Sheldon