SU1704764A2 - Device for measuring critical frequency of flickering fusion - Google Patents

Abstract

The invention relates to medical technology, namely, devices for assessing the psycho-physiological state of a person, and can be used in vocational guidance, in operative monitoring of human performance, as well as in diagnostic purposes. A device for measuring the critical frequency of light flashes through the introduction of splitter 20 into two, valve 21, sixth trigger 22 and switch 23 allows the subject to reduce the number of light flashes below the flicker frequency in the case of a large response time and thereby reduce the number of re-tests, and therefore , increase the reliability of the results. 2 Il.

Description

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The invention relates to medical technology, namely, devices for assessing the psycho-physiological parameters of a person, and can be used in vocational guidance, in operative monitoring of human performance, in determining human fatigue during a work shift, as well as for diagnostic purposes.

The purpose of the invention is to increase the reliability of research results by reducing the measurement time by reducing the number of repeated tests.

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

The device contains the test button 1, the shift register 2, the first 3, the second 4, the third 5, the fourth 6, the fifth 7 triggers, the first 8, the second 9, the third awaiting multivibrators, the switch 11 modes, linear voltage generator 12, the converter 13 voltage - frequency, source of 14 light pulses, element OR 15, average value calculator 16, indication block 17, comparator 18, LED 19, divider 20 into two, valve 21, sixth trigger 22 and switch 23.

Triggers 3-7, 22 are standard R-S triggers. Of the 3-7 triggers, only one can be in the on state at a time.

As a linear voltage generator 12, a standard integrator is used on an operational amplifier with input registers switched by switch 11 to obtain a different voltage rise rate at the output of generator 12, and the polarity of the input voltage is changed to change the direction of integration (increase or output voltage drop).

The calculator 16 determines the average of two values of the frequencies of light flashes recorded by the subject.

The comparator 18 generates a signal when the input voltage is reduced or exceeded relative to the values corresponding to the minimum and maximum cfs equal to 20 and 50 Hz, respectively.

Divider 20 is a D-flip-flop, which is split in two.

In the initial state, the switch 23 connects to the waiting multivibrator 8 the time the driving circuit with parameters determining the decrease in the frequency of the light

flicker on the time interval at 5 Hz, after the inclusion of the trigger 22 - 10 Hz.

The device works as follows.

When the power supply of the trigger 3-7, 22 is turned off, the divider 20 is zeroed, the code 2,000 is written to the register 2, the generator 12 outputs a constant voltage to the converter 13, corresponding to the initial oscillation frequency FI. Converter 13 converts this voltage to a frequency that controls source 14 (time interval 0-Ti).

5 The subject presses button 1 (time TI). A pulse from button 1 sets a 20 O divider at the inverse output and closes the valve 21. At the same time, the pulse of button 1 shifts the state of register 2 by one bit to the right, the signal from the first output of register 2 turns on trigger 3, which through switch 11 sets the generator 12 the mode of generation of fast-changing linearly rising voltage with the Si slope. Converter 13 converts this voltage into a proportional variable frequency, which source 14 converts into light pulses presented by

0 to the subject (Ti-T2 time interval).

At the P-T2 time interval, the subject determines the moment of the flicker of light flashing, in which he presses button 1. In case the subject misses this point and does not press button 1, the comparator 18 turns on the indicator 19 and causes triggers 3-7, the divider 20, register 2 and generator 12 to the initial state (circuits not shown).

0 When button 1 is pressed (time point T2, frequency F2), a pulse from it sets in the inverse output a divider 20 1 and opens valve 21. At the same time, the state of register 2 is shifted again by one

5 bits to the right. The signal from the second output of register 2 turns off the trigger 3, starts the multivibrator 8 and turns on the trigger 4, the latter through the switch 11 sets the generator 12 to the generation mode

0 fast linear supply voltage with a slope of $ 2. The time interval t2-T3 is determined by the parameters of the time of the driving circuit connected to the multivibrator 8 by the switch 23, with

5, the frequency is reduced by a fixed amount equal to, for example, 5 Hz. At the moment of time Ts, the multivibrator 8 is turned off and the back edge of the pulse turns off trigger 4 and activates trigger 5, which through switch 11 sets generator 12 to the generation of a slowly varying linearly increasing voltage with slope 5z transformed along a circuit 12 - converter 13 - source 13 14 in light pulses (time interval Tz-T / s).

At the time interval Tz-T4, the subject again determines the time of the flicker of light, in which he presses the button 1. If, due to the reaction time of the subject, a decrease in the frequency of light flashes by 5 Hz in the time interval is not enough, the subject does not see at the time point Tz light flashes and at the time interval Tz-T4 does not press button 1. Comparator 18 through an open valve 21 turns on a trigger 22, which switches the switch 23, which connects to the multivibrator 8 time a driving circuit designed for an extended interval l the time at which 12umenshaets oscillator frequency by an amount equal to, for example, 10 Hz. At the same time, the comparator 18 causes the triggers 3-7, the divisor 20, the register 2 and the generator 12 to the initial state. In this case, the tests are resumed by pressing button 1 (time point Ti).

At the time of light flashing (time Tz. Frequency F), the subject presses button 1, register 2 is shifted by one bit to the right, the signal from its third output turns off trigger 5 and turns on multivibrator 9. The generator 12 keeps This voltage corresponds to the frequency F1. From the output of the multivibrator 9, the pulse through the element OR 15 goes to the calculator 16 ,. in which the frequency value F1 is written. The time interval TV-Ts is determined by the duration of the pulse generated by the multivibrator 9. At time Ts, the multivibrator 9 is turned off and the trailing edge of the pulse turns on the multivibrator 10 and the trigger 6, the latter through the switch 11 sets the generator 12 to the generation of fast-ramp voltage with slope Sa, the frequency is increased by 5 Hz. The time interval Tz-Te is determined by the duration of the pulse produced by the multivibrator 10. At the moment of time Te

the multivibrator 10 is turned off and the back edge of the pulse turns off the trigger 6 and turns on the trigger 7, the latter through the switch 11 sets the generator 12 to

the generation mode of a slowly varying falling voltage with an S3 slope converted by a circuit generator 12 - converter 13 - source 14 to light pulses (Te-T time interval). At the time of light flashing (time T, frequency F, the subject presses button 1, state of register 2 is shifted by one bit to the right, the signal from its fourth output turns off trigger 7, generator 12 maintains a constant voltage at the output frequency F. At the same time, the signal from the fourth output of register 2 through the element OR 15 is fed to the calculator 16, which is written to

the value of the frequency F. In the calculator 16, the average value of the frequencies F1 and F is determined and the result is output to the display unit 17. At the end of the process, the computer 16 generates a pulse, setting

the device is reset (chains are not shown).

In the event that the subject misses the time of the flicker of light on the Te-T time interval, the comparator 18 triggers triggers 3-7, divider 20, register 2 and generator 12 to the initial state.

Claims (1)

The invention of the device for measuring the critical Frequencies of flashing on aut. St. No. 1623605, characterized in that, in order to increase the reliability of research results by reducing the measurement time by reducing the number of repeated tests, a divider into two, a valve, a sixth trigger and a switch are added to it, the divider's input being connected to two with the output of the button of the test, the inverse output with the first the input of the valve, the second input of which is connected to the output of the comparator, and the output to the first input of the sixth trigger, the second input of which is connected to the output of the average value calculator, and the output to the input switch, the output of which is connected to the second input of the first standby multivibrator. / V 71 72 7374 T 76 Phage. 2 77