Gas-discharge lamp they create light from electricity considerably more efficiently than incandescent light bulbs. The father of the low-pressure gas discharge tube was German glassblower Heinrich Geissler, who beginning in 1857 constructed colorful artistic cold cathode tubes with different gases in them which glowed with many different colors, called Geissler tubes. It was found that inert gases like the noble gases neon, argon, krypton or xenon, as well as carbon dioxide worked well in tubes. This technology was commercialized by French engineer Georges Claude in 1910 and became neon lighting, used in neon signs. The introduction of the metal vapor lamp, including
Phase-out of incandescent light bulbs source is similar in character to that from a Planckian "black body" in spectral distribution, that is, the bulb, as the filament heats up, produces light from wavelengths throughout the visible spectrum. Alternative light sources use phosphors or combinations of mono-chromatic LEDs (red, blue, green) to produce "white" light, giving significantly irregular spectral distributions which can result in color casts in photography and differences of color matching when compared to incandescent light or daylight. Halogen lamps are a type of incandescent lamp with improved efficiency over regular incandescent lamps. Though not as energy efficient as other alternatives, they are up