| 摘要 |
<p>The present invention relates to a system for the study and calculation of the visual field, which has basic novelty features as well as considerable advantages over existing means, used for this same purpose. The basic idea consists in the use of a wide surface cathode ray tube (CRT) as a campometric screen, so as to generate background and luminous stimuli capable of provoking a positive response of the subject explored. An original system of generation and amplification of the video signal also allows presenting, simultaneously, a background of variable luminosity which fills up the surface of the screen, luminous test stimuli with variable luminosity and location, as well as the points necessary to maintain fixation, as a function of the type of exploration to be performed. This is obtained by means of a triple excitation of the cathode ray tube cathode, through an output amplifier specially designed for this purpose. The background and test stimuli luminosity cover, independently, a range of discreet values, in a scale which allows great resolution, ranging from a maximum to minimum light flux linear ration of 10,000:1, enough to encompass the practical totality of the peripheric explorations.</p> |
