in november 2007, the university of arizona's 3dvis lab (3d visualization and imaging system lab), led by director dr. hong hua, developed a polarized head-mounted projection display where the polarization states of the light are deliberately manipulated to maximize the luminous transfer efficiency. it comprises a pair of high-resolution ferroelectric liquid-crystal-on-silicon (flcos) microdisplays that help to further improve theoverall light efficiency and image quality and have much higher optical efficiency than a transmissive-type lcd.