91色情片

Virtual reality isn鈥檛 very real if the 3D picture flickers. Isis Innovation
of Oxford has fixed the problem with a liquid crystal focusing device (W0
98/18039). A VR screen shows a rapid sequence of left and right images. Isis
proposes using ferroelectric liquid crystal plates which behave like Fresnel
lenses. This lets the screen 鈥渟witch鈥� so that each eye only sees the perspective
relevant to it. Switching takes place up to 1000 times a second giving the
viewer a flicker-free 3D image.