| 摘要 |
A device (10) for controlling a cursor on a data terminal display screen (18) is in the form of a headset and includes an orientation sensor (28) which provides an electrical signal related to orientation without being fixed to a surface. The sensor (28) includes a hollow spherical housing (38) having at least one light source/detector pair (70, 72) mounted opposingly in the inner wall (74) along an axis extending through the center point of the housing. The housing (38) is half-filled with a transparent liquid (76) having a specified viscosity and index of refraction and half-filled with air (78). A beam from source (70) is refracted on passing through the boundary between the air and the liquid. As the orientation sensor (38) rotates with respect to the vertical axis, the changing refraction angle of the light beam causes the detector (72) to sense changing intensities of light, which represents angle of rotation. |
