| 摘要 |
<p>Apparatus for the determination of corneal thresholds, for example the corneal center, through the use of air flow to specific corneal sites, comprises a ''stimulate'' air flow path (19) leading from an air compressor (4) through a stimulate nozzle (9) to the cornea for stimulation, and a ''non-stimulate'' air flow path leading from the air compressor (4) to a calibrate nozzle (91), so that the force in the stimulate nozzle may be set before stimulation. A further ''exhaust'' air flow path is provided quickly to exhaust air from the stimulate nozzle to provide a sharp turn-off of the force of the air flow applied to the optic cornea, thereby obtaining a substantially rectangular stimulation characteristic. The nozzle (9) is wide and flat with a dimple or recess formed substantially at or near the center thereof where air exits therefrom, so that the force and extent of air needed to stimulate the cornea is limited.</p> |
