I've got one of those heat lamps that produce a lot of infrared light and I've noticed the light sensor on my phone seems to be sensitive to that wavelength.
The lamp is 250 watts and aimed at the ceiling in a dimly lit room and it doesn't shine in any horizontal direction. However, the screen on my phone goes to very bright when ever the heat lamp is on. The phone is also about 15 feet away from the lamp and the screen is laying horizontal not toward the lamp. The part of the room where the phone is located is very dimly lit.
I've also got a CFL lamp tuned on in the same room, but the phone screen doesn't seem to light up unless the heat lamp is on. So I suspect the phone's light sensor is especially sensitive to infrared, but not sensitive to the light from a CFL bulb.
The lamp is 250 watts and aimed at the ceiling in a dimly lit room and it doesn't shine in any horizontal direction. However, the screen on my phone goes to very bright when ever the heat lamp is on. The phone is also about 15 feet away from the lamp and the screen is laying horizontal not toward the lamp. The part of the room where the phone is located is very dimly lit.
I've also got a CFL lamp tuned on in the same room, but the phone screen doesn't seem to light up unless the heat lamp is on. So I suspect the phone's light sensor is especially sensitive to infrared, but not sensitive to the light from a CFL bulb.