SU1643993A1 - Device for measuring and counting particles in liquids - Google Patents

Description

one

(21) 4302077/25

(22) 07.20.87

(46) 04.23.91. Bul Number 15

(71) Kuibyshev Aviation Institute. Acad. S.P. Koroleva

(72) C. V. Prokudin, N. A. Malygin, L. M. Logvinov and M. N. Kudr Shova (53) 535.242 (088.8)

(56) USSR Author's Certificate No. 907422, cl. G 01 N 15/02, 1982. USSR Copyright Certificate No. 1333028, cl. G 01 N 15/02, 1985.

(54) DEVICE FOR MEASURING SIZES AND NUMBER OF PARTICLES IN A LIQUID

(57) The invention relates to a measurement technique and is intended for the analysis of dispersion media. The aim of the invention is to increase the sensitivity of measurements of the size and number of particles by increasing the accumulation time of signals from particles. A row of photocells of the photodetector 5 is placed in the image plane of the optical system 4. The signals from the photoelectric cells are removed sequentially and synchronously with the movement of the image of particles. They accumulate these signals with the subsequent determination of the sizes and the number of particles. 1 il.

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The invention relates to a measurement technique and is intended for the analysis of dispersion media.

The aim of the invention is to increase the sensitivity of measurements.

The drawing shows a diagram of the device.

The device comprises a surface 1 for deposition of particles 2 on it, having the possibility of movement, an illumination source 3, an optical system 4, a photodetector 5 consisting of a series of photocells connected to a delay line 6, an electronic unit 7. The illumination source 3 forms on surface 1 zone 8 light.

The device works as follows.

Surface 1 is set in motion, particles 2 are deposited on it. Moving surface 1 with particles 2 deposited on it is illuminated by a beam of light from the source 3 of the radiation. Using the optical system 4, the image of the particle 2 is projected onto the photodetector 5 located in the image plane of the optical system 4.

When particles 2 enter the illumination zone 8 (position I), the image is first projected onto the first element of the photodetector 5. This element produces an electrical signal U, which is fed to the input of delay line 6. Then, upon further movement of the particle 2 through the illumination zone 8 (position II), its image is transferred to the second element of the photodetector 5. At the same time, the second element generates an electrical signal U, which is fed to the second input of the delay line 6. The delay time of the signal from the previous photocell ts is chosen to be equal to the time during which the image of the particle moves from one photocell to another. Therefore, at the moment of transfer of the particle image to the third photocell, the accumulated signal from this particle is already, and so on.

Thus, when particle 2 leaves the illumination zone 8, the signal from this

ten

the particles at the output of the delay line b are

U Ui + U2 + ... + Un.

This signal is applied to the electronic g unit 7 for processing. The amplitude of this signal for the same particle is n times larger than in the case of a single receiver.

At the same time, the level of the fluctuation component of the noise increases, i. .-. This allows us to increase the sensitivity of measurements by 15, because the signal-to-noise ratio significantly increases due to the accumulation of signals, and the sensitivity increases without loss of resolution.

When using a ruler of 100 pho to20 cells, for example, the sensitivity of the device increases 10 times.

Claims (1)

Invention Formula -c A device for measuring the size and number of particles in a liquid, containing a radiation source and a surface along which the radiation is deposited, to deposit particles that can be moved uniformly perpendicular to the optical axis of the device, an optical system and a receiving device connected to an electronic unit By the fact that, in order to increase the sensitivity of the measurements, the device additionally contains a delay line, the receiving device is 35 defined as a line of photocells arranged lengthwise direction of movement of the surface to deposit the particles with the number of delay line inputs equal to the number of photocells, each photocell output connected to a corresponding 4® input line delay, and the output of the delay line is connected to the input of the electronic unit.