Ferroelectric liquid-crystal shutter array with a-Si:H TFT driver

A ferroelectric liquid crystal (FLC) shutter array with an a-Si:H thin-film transistor (TFT) drive, designed for a low-cost and high-performance optical printing head, is presented. The a-Si:H TFT driver consists of inverter circuits, switch TFTs, and matrix circuits. A block driving method was employed to compensate for the low operating speed of the a-Si:H TFTs. The 256-dot, 300-dot/in resolution prototype device mounted in a printing head shows an over-30 contrast ratio and an 8-page/min operating speed. Additional measurements on this device demonstrate the possibility of operation with a 24-page/min speed at a 600 dot/in resolution.<
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