| 摘要 |
medicine; medical engineering. SUBSTANCE: method involves placing optoelectronic device between a blind person and scene under observation. The device enables one to transform scene illumination changes into frequency- variable acoustic signals in two channels and send them into blind person head telephone units. The blind person interprets changes in acoustic signals as arrival, availability and vanishing of an object on the scene. The optoelectronic device allows separate control of illumination in M-zones of the scene, where M is equal to 2,4,:K,:M. A half of them corresponds to the left part of the scene and the other one to the right one. The predefined frequency of the acoustic signals to be converted in each K-zone of the left and right scene parts differs from those assigned to the other zones. Occurrence of acoustic signals of the corresponding frequency is interpreted by blind person as direction to the object. The set frequency changing, change in object movement direction event is understood to take place. The rate of frequency variation is interpreted as object traveling speed. The number of concurrently sounding signals of different frequency is related to horizontal dimensions of an object and the number of objects. The device has objective and electronic circuit composed of two independent channels each having photosensitive receiver placed in focal plane of the objective and electrically connected to acoustic frequency oscillator unit loaded on telephone unit. The photosensitive receiver is manufactured with N inverting photocells (N=1,2,:K,:M) in each channel. Acoustic frequency oscillator unit has N cascades of preset unequal frequencies. Each K-photocell is connected to K-cascade of fixed frequency. Cascade outputs are connected to head telephone unit of the given channel through N inputs of matching amplifier. Fixed frequency K-cascades are tuned in both channels to equal frequencies. N-cascade frequencies grow with growing cascade number from 1 to N. EFFECT: wide range of functional features and applications. 4 cl, 1 dwg _ |
