What kind of light bulb gives off the highest energy of photons?
Gintable is correct in that the energy of photons is proportional to wavelength, so the shorter wavelength photons have more energy. The brightness of a light is due to the number of photons per second. In this area the comparison is usually made as the efficiency in converting electrical energy into light energy (luminous flux), so lumens per watt. Incandescent lamps (quartz iodine) are generally up to 18lm/W, practical LED laps about 80lm/W and fluorescent lamps about 80lm/W. However LEDs have the potential for double that capability. You can compare these sources with the sun by shining them on a piece of white paper in the sun. Single colour leds are often brighter than the sun, at a particular wavelength, but it is hard to beat the sun for overall brightness. Note that using lumens takes into account the visible wavelengths and how well we see various colours. Otherwise incandescent lamps would do better, as a lot of their output is infra red, not visible light. A green light is m
