Title :
Video camera system using liquid-crystal polarizing filter to reduce reflected light
Author :
Fujikake, Hideo ; Takizawa, Kuniharu ; Aida, Tahito ; Negishi, Toshihiro ; Kobayashi, Michio
Author_Institution :
NHK Sci. & Tech. Res. Labs., Tokyo, Japan
fDate :
12/1/1998 12:00:00 AM
Abstract :
We have been developed a video camera system using an electrically-controllable liquid crystal polarizing filter for television program production, which can quickly reduce undesirable reflected light from a window pane or watery surface, by automatically judging the polarization state of incident light from the change in video signal intensity. More than 80% of linearly-polarized incident light is removable by this method for all incident polarization angles. The time required for detecting and reducing reflected light is approximately 0.3s in our system. The drastic reduction of polarized light reflected from glass and watery surfaces was demonstrated, and object images obscured by bright reflected light were clearly captured in an instant
Keywords :
light polarisation; liquid crystal devices; optical filters; television cameras; video cameras; linearly-polarized incident light; liquid-crystal polarizing filter; object images; polarization state; reflected light; television program production; video camera system; video signal intensity; watery surface; window pane; Cameras; Glass; Liquid crystals; Optical films; Optical filters; Optical polarization; Optical reflection; TV; Vehicles; Windows;
Journal_Title :
Broadcasting, IEEE Transactions on