| 摘要 |
PCT No. PCT/GB96/02233 Sec. 371 Date Nov. 12, 1998 Sec. 102(e) Date Nov. 12, 1998 PCT Filed Sep. 9, 1996 PCT Pub. No. WO97/08985 PCT Pub. Date Mar. 13, 1997The invention relates to a point of observation tracking device comprising means (8, 12) for directing light from a holographic element (12) to the retina (4) of a user, and means for tracking the reflection of the light (12, 14) from the retina (4) thereby to provide a signal representative of the point of observation of the eye or eyes of the user. |
