Researchers at the University of Illinois Ilyuev made thin-plate microcavity plasma lamps. This light is lighter, brighter, and cheaper than incandescent lamps. It is made of aluminum foil, sapphire and a small amount of gas. The plasma sheet lamp is made of two aluminum foils sandwiching a thin layer of transparent alumina (sapphire) dielectric. In the center of the lamp there is a cavity that passes through the aluminum foil and sapphire. The thickness of the plate lamp is less than 1mm and can be hung on the wall like a picture frame. Some are similar to ordinary fluorescent lamps. Microcavity plasma lamps are glow discharge devices; gas atoms are excited by electrons and radiate light. However, the plasma in the microcavity plasma lamp is formed in a tiny cavity without the need for ballasts, reflectors, and heavy metal shells.
A panel light with 200 square centimeters of light has been produced. Due to the different gases or phosphors charged, this lamp emits different uniform colors. This light is lighter and brighter than an incandescent light. With the improvement of the process, the luminous efficiency of such lamps may reach or even exceed the level of fluorescent lamps.