In the specific example of the light bulb, the current passing through the thin wire heats it to the point of incandescence. The molecules composing the wire, change energy states as they interact with the electrons of the current and emit a spectrum of electromagnetic radiation starting with infrared up to visible light in frequencies.
from the link:Unfortunately, the spectrum emitted by a blackbody radiator does not match the sensitivity characteristics of the human eye. Tungsten filaments radiate mostly infrared radiation at temperatures where they remain solid (below 3683 kelvins / 3410 °C / 6,170 °F). Donald L. Klipstein explains it this way: "An ideal thermal radiator produces visible light most efficiently at temperatures around 6300 °C (6600 K or 11,500 °F). Even at this high temperature, a lot of the radiation is either infrared or ultraviolet, and the theoretical luminous efficiency is 95 lumens per watt." No known material can be used as a filament at this ideal temperature, which is hotter than the sun's surface. An upper limit for incandescent lamp luminous efficacy is around 52 lumens per watt, the theoretical value emitted by tungsten at its melting point.
Now fluorescent lamps do not depend on incandescence to emit light: CFLs emit light from a mix of phosphors inside the bulb, each emitting one band of color. Modern phosphor designs balances the emitted light color, energy efficiency, and cost. Every extra phosphor added to the coating mix decreases efficiency and increases cost. Good quality consumer CFLs use three or four phosphors to achieve a "white" light with a color rendering index (CRI) of about 80, where the maximum 100 represents the appearance of colors under daylight or a black-body (depending on the correlated color temperature).
The mixture of phosphors in the fluorescent lamps exhibits the "control" you are asking for, the spectrum is weighted towards visible light and not infrared as the article in the link analyzes.