SU573723A1 - Photometer - Google Patents

Description

I

The invention of the field of photography and photoelectric imaging can be used in photometric systems and instruments of analytical control.

Photometers are known with alternating measurements of the measured and reference light fluxes per photodetector, c. which they are equalized with an optical attenuator. Short The number of such photometers is low measurement accuracy and speed.

Of the known photometers, the closest to the technical essence of the invention is a photometer containing a photo detector, an amplifier, a phase detector, an input that is connected to the output of the amplifier, an indicator connected to the output of the phase detector, and a light source optically connected to the photodetector (3 Using an electromechanical modulator in the photo, the receiver alternately sends the measured and reference luminous flux from the source of light. The variable photoelectric signal is amplified, detected by the Phase Detector and under is on the light source

as a result, balancing of both light fluxes occurs and high metrological characteristics are ensured. The disadvantages of the photometer are low reliability and complexity of the design, caused by the presence of an electromechanical modulator.

The purpose of the invention is to increase reliability and simplify the design of the photometer.

This is achieved by the fact that in a known photometer there is a composite photodiode, an amplifier, a phase detector, the input of which is connected to the output of the amplifier, an indicator connected to the first phase detector, and a light source that is optically connected to the amp; a terrestrial receiver, a resistor divider, two keys, and a control voltage generator were inserted, the input of the resistor divider connected to the output of the photodetector, and

output - with the input of the amplifier, one of CL1O.

Claims (1)

whose one is connected to one of the resistor divider resistors, the input of the second switch is connected to the output of the phase detector, the output of the second switch is connected to the light source, and the control inputs of the keys in the phase detector are connected to the outputs of the controlled voltage generator. The drawing shows the scheme of the proposed photometer. The photometer contains a photoconductor 1, x output is connected to a resistor divider CONNECTING the resistors 2 and 3, to one of which is connected key 4. To the output of the resistor divider are connected in series amplifier 5, 1st detector 6 and indicator 7, output phase detector 6 connected to the input of the key 8, the output of which is connected to the source 9 of the light. The control inputs of the keys 4 8 and the faeo detector 5 are connected to the schlokhodamn generator 1O control. shechu ,, Photo1. It works in a dim way. FotiriemE.1 1 is illuminated by a constant Nemer ek m of the light flux P and a light flux F from the source 9 of the light. The light flux Φ modular foan is periodically closed and opening the key 8 controlled by the generator 10 control voltage, in such a way that the total light flux φ is equal to: φ, φ (((& nt Dt), where is the amplitude of the light flux , D is the modulation frequency, t is time, 3 {{this function, i Synchronously with the key 8, the key 4 is working, the perpendicularly closed resistor is 2, and the closed state of the key 4 corresponds to the open state of the key 8, i.e. Coefficient Terepachi Divisor Kdel.R “Eun: LK LK sigw (siM At) affairs 22 Here C - the coefficient of division k on the resistors 2 and 3. As a result, the signal Ug at the output of the divider is equal; Pers.3.3 - Aed 1 H ° + (-K) FL- & ё (where 3 is the slope of the converter, phototransmitter. This signal amplifies the amplifier 5 and detects the phase detector 6, which operates synchronously and phase with the keys 4 8. As a result, the output of the phase detector 5 forms a constant voltage Lfgj ,,., о (1-к) Ф,) Through Kg denotes the total transmission coefficient amplifier path otometra. But the magnitude of the luminous flux is proportional to the output voltage Ugy by some conversion coefficient p c, - / 3, xg (2) Therefore, substituting (2) into (l) we find that the output voltage supplied to the indicator 7 is: M1--) expression (3) shows that the output of the photometer is proportional to the measured luminous flux Φ (and of a large negative feedback) it does not depend on the transmission of the forward recording path and, therefore, on its instability. Thus, the proposed photometer retains the high metrological characteristics of optical feedback photometers and eliminates the electromechanical modulator, which makes it possible to increase the reliability and simplify the design of the photometer. A photometer comprising a photodetector, an amplifier, a phase detector, whose input is connected to an amplifier output, an indicator connected to the output of the phase detector, and a light source optically coupled to a photodetector, characterized in that, in order to ensure reliability and simplify the design, A resistor divider, two switches and a control voltage generator are entered into it, the resistor divider input being connected to the photodetector bypass, and the output to the amplifier input, one of the keys connected to one. of the resistors of the resistor divider, the input of the second switch is connected to the output of the phase detector, the second switch J of the second switch is connected to the light source, and i control the inputs of the CLA. whose and phase detectors are connected to the outputs of the control voltage generator. Sources of information taken into account in the examination: 1, N. Chechik O, and others. Electronic multipliers State. tehniJ8: o-teopticheskoy literature, 1954, p., 216. 2, Seidel, AN and others. Technique and practice of spectroscopy, M., - Science 1972, p. 321. 3, Novitsky P.V. Electric of; ivory of non-electric quantities L., Energie, 1975, p. 452.