Techniques to Reduce Driving Energy of 1-Pixel Displays

We propose a pair of techniques to lower the energy consumed by driving 1-pixel liquid-crystal displays (LCDs). The first one employs multiple capacitors while the other divides the LCD into two to lower the drive voltage. Simulations show that large capacitance values and many capacitors reduce the energy consumed, and stacking two thin low voltage LCDs maximizes the effect by decreasing the overhead consumed by the microcontroller. Actual polymer-dispersed LCDs (PDLCDs) are tested to confirm that the techniques work as effectively as the simulations imply. The results show that the overall energy consumption of large PDLCDs is reduced more than 70% using multiple capacitors, and the combination of the two techniques successfully reduces the driving energy even for small LCDs. While the polarity reversal of the proposed technique does incur some delay, it was confirmed by a flicker test that the technique does not degrade image quality.