Evaluation And Analysis Of Light Diffraction From One-Dimensional Liquid Crystal Devices Using Pixel Pitches More Than 1 Mu M

We compare the diffraction characteristics of ferroelectric (FLC) and nematic liquid crystal (NLC) devices with one-dimensional stripe patterns of 1-10 mu m pixel pitches. The polarizing micrographs show pixel boundaries of black/white pixels blur as the pixel pitch becomes smaller. The blur of NLC is more remarkable than that of FLC. The first-order diffraction efficiency of NLC remains constant for the pixel pitch of 4-10 mu m and sharply decreases for the pixel pitch of < 2 mu m. By contrast, the FLC efficiency decreases with the pixel pitch decrease from 10 to 4 mu m and remains constant for the pixel pitch of < 3 mu m. The FLC efficiency (5.5%) is four times larger than that of NLC (1.4%) with a 1 mu m pixel pitch. The Fourier transform calculation shows the efficiency degradation of FLC is caused by the blur at the pixel boundary, whereas that of NLC caused by the blur and contrast deterioration.