SU1478118A1 - Method of determining optical transmission factor of liquid bio-essays - Google Patents

Abstract

The invention relates to the field of medicine and can be used to conduct analyzes of biological fluids by optical transmission coefficient. The goal is to improve the accuracy of the method. To do this, liquid samples are placed in spaced cells of a transparent cassette, illuminated with transmitted light, a given spectral region is selected, the intensity at specified points of the cassette is determined, the cassette is masked, the image of the cassette is projected onto the signal of each sample and the difference the signals from the transparent and non-transparent areas closest to it and the coefficient are determined from the ratio of the values obtained. 1 il.

Description

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The invention relates to medicine, in particular to testing, and is intended to determine the transmittance of liquid biological samples.

The aim of the invention is to accelerate the method.

The goal is achieved due to the fact that the samples are placed in spaced cells of a transparent cassette, illuminate the sample cassette with transmitted light, select a given spectral region of light transmitted through the cassette and determine its intensity in the specified points of the cassette, the sample cassette is masked with transparent and opaque areas so that each cell

coincided with the transparent part of the mask, and the intervals between the cells to the left and right of the cell, respectively, with the transparent and opaque parts of the mask, design an image of a cassette with a mask on the target of the transmitting tube of the television camera, determine and memorize the signal from each sample and the difference of the signals from the closest to It has a transparent and opaque region of the mask, and an optical transmission coefficient is determined by dividing the signal from the sample by the difference obtained.

The drawing shows a diagram of the device that implements the proposed method.

In the device between the source of light 1 and the lens 5 of the camera 6 6

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Model 2 under test is masked with mask 3 and filter 4. The video signal from the camera output is fed to the input of the analog signal selection and storage device 8, in which the magnitude of the generated signal matches the maximum signal swing. The clock pulses produced by the camera are fed to the input of the driver 7 command signals and sample signals. The sampling signals generated by this block, each of which contains six pulses on four adjacent lines of decomposition, are set by the operator in the image on the screen so that the first pulse coincides with the white area (to the left of the object being measured), the second, third, fourth and fifth pulses combined with the image of the measured object, and the sixth sampling pulse coincided with the image with the black area (to the right of the measured object).

On an external command in the next sweep frame, the sampling pulses in the device 8 for sampling and storing the analog signal strobe the video signal in points. At the output of an analog signal sampling and storage device, analog signal pulses are generated, the amplitude of which is determined by the magnitude of the video signal at the time of gating. These pulses, which occurred at the time of gating (, are valid until the end of the line.

Each ich pulse of the analog signal of the sample is fed to the input of its comparator unit 10 comparator. At the same time, the second inputs of all comparators are supplied with a stepped signal from the output of the device 8 for sampling and storing the analog signal, as well as clock pulses from the output of the video signal converter 9 into a digit, which start from the end of the last of six pulses from the sample. The clock pulses are considered to be a counter, each bit of which is connected to the corresponding bit of a standard digital-to-analog converter.

The first and the sixth comparators of the 10 comparators block, to the inputs of which the signals of the reference levels of white and black are supplied, with the reference 0

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By quenching, the digitized signals of these reference levels are recorded in the arithmetic unit 11, where the signals of the reference levels are subtracted. The resulting difference in the reference levels determines the weighting factor used in estimating the optical density of the measured object, the signal of which is formed between two reference levels.

The signals from the four comparators of the 10 comparators block corresponding to the four sampling pulses coinciding with the object being measured, a. Also, all bits of the counter from the output of the video signal converter 9 are digitized to the inputs of the first digital integrator 12, at the output of which the average digital value of the video signal of the object being measured is generated.

The difference of the reference levels from the output of the arithmetic unit 11 is fed to the inputs of the second digital integrator 13, in which, according to commands from the output of the imaging unit 7 command signals and sampling signals, line-by-line summation and averaging of the differences of the reference levels on four adjacent scan lines is performed. The averaged signal of the level difference at the address supplied from the driver 7 of the command signals and the sample signals is recorded in an N-bit (N is the number of samples corresponding to the number of objects to be measured in the field of view) digital memory 15.

Similarly, integration (averaging) is performed over four lines of the signal level of the measured object in the second digital integrator 14 and the mean value of the measured signal is written to the N-bit second digital memory 16 at the same address. The relative optical density of any part of the image (of any object being measured) can be determined by dividing two quantities recorded and stored indefinitely in digital memory devices 15 and 16 when these values are read from memory by external commands of any microprocessor or computer. having an interface.

Claims (1)

Invention Formula The method of determining the optical transmittance of liquid biological samples by placing the samples in spaced cells of a transparent cassette, illuminating a cassette with samples of transmitted light, highlighting a given spectral region of light transmitted through the cassette and determining its intensity at specified points of the cassette, characterized in that accelerating the method, the sample cassette is covered with a mask containing transparent and opaque areas, while the transparent areas are aligned with the cells, and the intervals between the cells to the left and right of the cell are correspondingly transparent and non-transparent areas of the mask and the optical transmittance is determined by the ratio of the signal from each sample and from adjacent areas of the mask. A 5 J: