I'm currently using a photodiode (found here) along with the appropriate emitter to send data between mobile robots. I'd like to the sensor to optionally be used as an ambient light sensor using a filter with lower sensitivity.
My trouble is picking out what this "ambient light" should be. Since the photodiode is only sensitive between 750 and 1150 nm, I imagine I need an IR bulb. However, every IR bulb I look at doesn't seem to specify what wavelengths it outputs. They also seem to all be used as heat sources, which I'm not sure I need. Ideally I'd like a cheap option that I could just stick in a lamp, but I'm open to other ideas. Does anyone know where to buy the correct IR bulb? Or what the correct IR bulb would be?