This is the forth post of the Macroelectronics.org OLEDs series. Stay tuned.
AMOLED, or active matrix OLED, is composed of an anode, a cathode, an organic layer, and a thin film transistor (TFT) matrix. Each pixel of the OLED is integrated onto a TFT array. TFT array controls the amount of current flows on each pixel which determines the brightness of generated light.
Instead of having external circuit to turn on/off the cathode and anode stripes that activate pixels in passive matrix configuration, AMOLED allows the current to flow through all of the OLED pixels while having TFTs controls how much current will each pixel gets. This is one of the advantages of AMOLED over PMOLED because TFT arrays need less power than external circuit. In addition, AMOLED’s pixel turns on and off at an incredibly rapid rate making it ideals for motion pictures. Though, AMOLED’s main disadvantage is its expensive manufacturing cost due to the intricacy of the active matrix structure that requires complex processes to fabricate.
Many leading display companies today such as Samsung, LG, Sony, Universal Display, Nokia and Kodak see a potential of and working on developing AMOLED displays. AMOLED now has become a promising technology for large display and portable display products.