| 摘要 |
<p>1353938 Testing vision; automatic electric control OCULOMETRICS Inc 13 July 1971 [13 July 1970] 32828/71 Headings G2J and G3N A process for testing the visual field of a subject 21 comprises presenting, under machine control, momentary, stationary spots of light of selected stimulus value at selected locations in a two-dimensional test field 24; determining, in response to a subject response device, e.g. "joystick" 31, whether the subject correctly perceived the spot, correct perception being assumed if the response was within a predetermined distance from the actual position of the spot, and presenting, under machine control, additional stationary spots of light of computed stimulus value different from those previously presented at a spot location, until either a threshold has been established or a spot of maximum stimulus value has been presented and not perceived. The term "stimulus value" denotes a measure of the noticeability of the spot, and depends on the size, brightness and direction of the spot. All equally noticeable spots have the same stimulus value. An indication of the correctness of a response, e.g. audible may be provided to the subject. A computer program is described which controls the process, and enables display of the field of vision, determination of vision threshold contours and plotting the shape of the blind spot. The program includes a routine for identifying which eye is under test by applying a spot which should be in the blind spot of the right eye. A number of spots which should image on the blind spot may also be applied to determine the degree of fixation of the subject.</p> |
