An AC or DC microdischarge device that comprises a fluorescent conversion material (FCM) and a multiplicity of gas filled microcavity cells, each cell being connected to two or more electrodes to cause a gas discharge in the cell, the gas discharge providing photons that excite the FCM such that the FCM emits IR. In one embodiment, the electronic circuitry for each cell comprises at least one integrated active component such as a transistor. Other active components may be included such as a high speed shift register, addressing logic, and/or control circuits. In another embodiment, the microcavity and active components are made from the same substrate such as the same silicon wafer. The microdischarge device may include one or more electrodes encapsulated in a dielectric. The electrodes are configured to ignite a microdischarge in a microcavity cell when an AC or a pulsed DC excitation potential is applied between the electrodes connected to the cell. The devices include linear and planar arrays of microdischarge devices. The microcavities in the planar arrays may be selectively excited for display applications.