SU84227A1 - Photoelectric pyrometer for determining the color and brightness temperature of light sources - Google Patents

Description

Devices for measuring color temperature based on determining the blue-red ratio of the constituents of the light are known. These devices use selenium photovoltaic cells under red and blue light filters, which are subject to fatigue and work well only when the light intensity level is prevented.

The proposed photoelectric pyrometer eliminates these disadvantages due to the use of vacuum elements and an electron-amplifying device.

The drawing shows a diagram of the described pyro.metra, in which the Y-amplifier; / Ci and / Sa - resonant circuits; O: and Oo - amplitude limiters; Oz - phase detector.

Using a disk with integrated light filters / photocell, then one or the other spectral brightness is applied. The photocurrent is supplied to the amplifier Y, at the output of which current pulses (voltages) are obtained, the amplitude of which is proportional to the corresponding spectral luminance. The system is designed in such a way that the pulses are shifted in phase by l / 2. The components of the fundamental frequencies of these UMnyniv are: -; fluctuations will be:

 - /-/..msinwf (1)

(/./ch2 la / n, sin (loi g .... (2)

. The main value of the resulting oscillation at the output of the resonant circuit K, tuned to the fundamental frequency of the pulses, can be obtained as;

/ V) sin (o) / + (p) .... (3)

2

, and X, t

where: f arc tg-.

su wj rn

No. 84227-- 2 Supply voltage (/ "the amplitude limiter and, when producing phase detuning, the value φ can be recorded at the output of the detector as a change in the amplitude of a certain voltage.; .1 O At the output of the last voltage, UKi - (Ul2 is obtained in the form of pulses of equal amplitude and duration. By applying these pulses to the circuit K.ch, which is absolutely identical in its parameters to the circuit / C, the output of K-. awoke from n The lipt is determined by the rotation speed of the obturator.

The voltage taken from the D2 is limited in amplitude, for which an amplitude limiter 0 is provided in the circuit. At the output of the Oo, voltage amplitudes of the voltage amplitude | 1 n irodo,

} - rer.; and nost11 7/2, where.

Applying voltage from the output of Og simultaneously with naniruyu 1 and J, (3), but in different phases, pa phase detector Oz, working for greater stability in the amplitude limiter mode, at the output of the last, the voltage in the form of almost rectangular pulses, in the duration of G / which will be displayed the value of l, t „.. the rank of the ratio. Indeed, the length of the considered

and .., t case, obviously, you can write:

t-, / x, / te

/ with - - arctg- (4

.t

Thus, by measuring any of the components of the current spectrum at the output Oz, it is possible to record (measure) the ratio IJKi-W, 2. In this ratio, in this case, the values of the color (p, branch) temperature are displayed, which, therefore, in the system under consideration can be recorded using any direct current device, registering, for example, the constant component of the current at the output Oz.

, and l, - - arctg In expression (5) -. with Mi-iioBeiuioc, it is significant as Os.

PREPARATION AND RESULTS

1. A photoelectric pyrometer for determining the color temperature of the light sources, characterized in that, in order to achieve measurement stability at low levels of brightness, it has two photo cascades from which output currents reflecting spectral or intrinsic brightness are applied to a resonant quadrupole and detected in phase, the sludge is folded in antiphase so that the magnitude of the current detected by the photoelectric nnrometer gives an indication of the color temperature along the red-blue current etstvuyunshh fotokaskadov. current on oipa