Active-matrix OLED

AMOLED (active-matrix organic light-emitting diode, /ˈæmoʊˌlɛd/) is a display technology used in smartwatches, mobile devices, laptops, and televisions. OLED describes a specific type of thin-film-display technology in which organic compounds form the electroluminescent material, and active matrix refers to the technology behind the addressing of pixels.

As of 2008^[update], AMOLED technology was used in mobile phones, media players and digital cameras, and continued to make progress toward low-power, low-cost and large-size (for example, 40-inch) applications.

An AMOLED display consists of an active matrix of OLED pixels generating light (luminescence) upon electrical activation that have been deposited or integrated onto a thin-film transistor (TFT) array, which functions as a series of switches to control the current flowing to each individual pixel.

Typically, this continuous current flow is controlled by at least two TFTs at each pixel (to trigger the luminescence), with one TFT to start and stop the charging of a storage capacitor and the second to provide a voltage source at the level needed to create a constant current to the pixel, thereby eliminating the need for the very high currents required for passive-matrix OLED operation.

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