| 摘要 |
<p>A sight testing instrument has a projector and a spherical surface forming part of an automatically registering zone, into the centre of which the line of sight of the patient is directed. The device is also used to obtain information from the patient regarding the receipt of signals on the retina. At the centre is a totally reflective prism (27) and a projection lens (28) which rotate about a horizontal axis. This is followed by an auxiliary prism (21) so as to follow a curved path (17), so that a beam of light passes through two axes of rotation the same distance from the projected field at all points of the hemisphere. The optical system is mounted on the side of a plate (15) onto which the beam is projected, and this plate rotates about a vertical axis.</p> |
