My current project includes a circuit with 3 940nm IR LEDs to be put on a glove. The LEDs are in series with a resistor and they are powered by a 9V battery. The LEDs are tracked by a Wii remote IR camera. It's important for the project to have 3 LEDs because they make a shape used for position and angle tracking.
However the beam width of those 3mm IR leds is too narrow (< 60 degrees) and the tracking fails as soon as the hand slopes even just a bit. Therefore I have bought 1W high power LEDs because they have a beam of 120 degrees. Now my concern is to provide enough power to the LEDs but simultaneously limit the light emission to keep the device safe for the eyes and save battery power.
The question is: can I reach these goals simultaneously with a 9V battery and a simple resistor (possibly by "underpowering" the LEDs) or should I change my circuit ? Would a PWM-powered circuit be necessary and in this case would a microcontroller be mandatory (a Lillypad maybe ?) ?
Thank you in advance for any advice or schematics.