SU1627130A1 - Device for measuring critical flicker fusion frequency - Google Patents

Abstract

The invention relates to medical technology and can be used for diagnostic studies. The shadow of the shadow image is an increase in reliable measurement results by reducing the fatigue of the subject's visual analyzers. The device for studying the critical frequency of the flicker fusion includes a pulse generator, a control panel, a light source, a frequency divider, an And element, a counter and a display unit, a second pulse generator, a one-shot and a pulse distributor, the light source being in the form of a linear-point pulse, and the divider Frequency is a divider by two, 2 or more.

Description

The invention relates to medical technology and can be used for diagnostic studies.

The purpose of the invention is to increase the reliability of measurement results by reducing the fatigue of the subject's visual analyzers.

FIG. 1 shows a functional diagram of the device; FIG. 2 is a time chart of his work.

The proposed device includes a generator 1 pulses, a remote control 2, a linear-point source 3 of light, a divider 4 frequencies into two, element 5 I, counter 6, a display unit 7, a generator of 8 second pulses, a one-shot 9 and a distributor 10 pulses.

The device works as follows.

ripvt in-power ,, generator 8, vyrabatyvz t pulses with a frequency of 1 Hz (on

Fig. 2.1) arriving at the input of the divider 4, at the output of which the pulse duration is 1 s (Fig. 2,2), the Single Vibrator 9 generates a short pulse on the leading edge of the pulses, resetting the counter L and the initial state (Fig. 2 3). The pulses from the output of divider 4 allow the passage of pulses from generator 1 through element 5 for 1 second. And counter 6 (Fig. 2.4), the output of which generates frequency code 1 in hertz, is generated. Moreover, pulses from the output of generator 1 are received the input of the distributor 10 pulses. The subject on the remote control 2 closes the key that supplies power to the source 3 of the light. The pulses from the output of the distributor 10 are fed to a line-point source 3 of light and cause a brightness of each point source alternately. The sensation caused by the light flash of a point source does not stop with its ending. With rare

ABOUT

to VI

with about

light flashes the feeling from them disappears until the next flash. The person tested by turning the knob of the potentiometer of the console 2 increases the frequency of the generator 1 to the state when the next light flash of a separate point source 3 of light is supplied against the background of the sensation generated by its previous light flash. At this moment, the subject sees the light as continuous, fixes it as a moment of light flashing and opens the key of the remote control 2, which supplies power to the source 3 of the light. To read the critical frequency of light flashes, the subject closes the key on the remote control 2, which supplies power to the display unit 7, which displays the frequency of the generator 1 in hertz. When the key is closed at the moment of time when you / where the divider has 4 pulse (Fig.2.2: 2.4), the subject sees the step of counting the frequency of the generator 1, which lasts from the moment the key is closed until the end of the output pulse 4 then for 1 s. counting result When the key closes during the absence of a pulse at the output of divider 4, the subject sees the result of counting the generator frequency 1 for the time elapsed the chip's chazhatic moment until the pulse begins at the output of the divider 4, then in section 1 with mt-mp account h t p.

The source of light 3 is made on the light fixture - type ah ALU B

Thus, the device doesn’t detect the moment of fusion of light / glimmer, reduces the measurement time,

0

five

0

five

five

helping to reduce fatigue of visual analyzers and increase accurate cii-i measurements, due to simplicity, autonomy and low power consumption, allows for research in field conditions.

Claims (1)

Apparatus of the Invention A device for measuring the critical frequency of flicker fusion, comprising a control panel, a frequency divider by two, element I, a counter, a light source, a display unit, a pulse generator, the output of the element I being connected to the first input of the counter, the output of which is connected to the first input the display unit, the first output of the control panel is connected to the first input of the light source, distinguished by the g 11 which, in order to increase the reliability of the measurement results by reducing the stimulation of the visual analysis of the test subject, it introduced a second pulse generator, a one-shot and pulse distributor, the output of which is connected to the second input of the light source, and the output of the pulse generator and to the first input of the And element, the second input of which is connected to the input of the one-shot and two frequency dividers, the input of which is connected to the output of the generator of pulses, the output of one-shot, h is connected to the second input of the counter, the second VUOD of the display unit is connected to the second output of the control panel, the third output of which is connected to the input of the generator-, op pulses, wherein the light source is formed linearly-point, AT four . "-, FIG T s 6 9 7 ten j U-j .t ABOUT fl FIG. Z