DE2442641C2 - Arrangement for setting microscopic objects - Google Patents

Description

a) Object not detected

b) Actual position of the object = target position

c) Actual position of the object ¥ = debit position

contains first switching means, which when not detected Object generate a standard advance signal through which an adjusting mechanism (54) moves the object slide advances a step perpendicular to the scanning direction of the rotating mirror, second switching means contains which one to the synchronization signal in the middle of the scanning period of the rotating mirror Generate center pulse, contains third switching means, which when the object's actual position deviates generate a signal from the target position before or after the central pulse, through which the adjustment mechanism (56) the object moves into the desired position in the scanning direction of the rotating mirror, four Contains switching means which when the central pulse coincides with the detection pulse a signal the centering of the object (object position = target position) and contains a priority circuit that generates the aforementioned Signals of the three switching means in the order of priority

a) Signal object position = target position

b) Signal object position # target position

c) Signal object not detected

linked so that only one signal is generated at a time.

2. Arrangement according to claim I _1, characterized in that the synchronization pulses are generated by a focused on the rotating mirror light source (48) and the second light detector (50) which are arranged in a position in which the synchronization pulse triggering on the second light detector incident light at a certain time interval from the beginning of the scanning of the slide by the rotating mirror.

3. Arrangement according to claim 1 or 2, characterized in that the adjusting mechanism the Object centered on an opening (28) of the energy converter (36).

4. Arrangement according to one of claims 1-3, characterized in that when one occurs Synchronization pulse the clock pulses of an oscillator (68) are fed into a pulse counter (72), which, after reaching a preselected count, transfers the output value to a decryptor (76) which generates the central pulse

5. Arrangement according to one of claims 1-4, characterized characterized in that to generate the signal moving the object into the desired position two-stage switching register (102,104) is provided whose first stage (102) is set by the synchronization pulse and reset by the center pulse and its second stage (104) connected to the first when a detection pulse occurs receives the state of the first stage and then receives a bistable directional signal as an output generates which indicates whether the detection pulse occurred before or after the center pulse

6. Arrangement according to one of the preceding claims, characterized in that a second Decoder (78) receives the output values of the counter and one at the end of the mirror scan The end pulse is generated by a first flip-flop (98) when the detection pulse coincides the middle impulse is set and its output together with the end impulse a gate (100) is supplied, which is the signal supplied to the energy converter object actual position = target position generated

7. Arrangement according to one of the preceding claims, characterized in that the output a second flip-flop (88) set by the detection pulse with the end pulse one second gate (106) is supplied, which generates a direction signal for the adjustment mechanism.

8. Arrangement according to one of the preceding claims, characterized in that over the adjustable frequency of the oscillator (68) the duration of each sample can be adjusted.

9. Arrangement according to one of the preceding claims, characterized in that a monostable Multivibrator (62) with an adjustable, monostable time period through the synchronization pulse is triggered and on its output pulse the oscillator with the generation the clock pulse begins, whereby by setting the center pulse in one with the field of view center of the energy converter coinciding scanning position occurs.

10. Arrangement according to one of the preceding claims, characterized in that the projection means a beam splitter (22) included.

The invention relates to an arrangement for the analysis-appropriate setting of objects on microscopic Slides whose optical characteristics are converted into electrical signals.

In the microscopic analysis of blood samples, the individual blood cells or cells, e.g. B. the Leukocytes, are counted and evaluated by trained laboratory technicians. A suggestion for automation This time-consuming, tiring and error-prone investigation contains the dissertation of J. W. Backus, "An Automated Classification of the Peripheral Blood Leukocytes by Means of Digital Image Processing",

University of Illinois, Chicago, 1971.

According to the further proposal of the application P 24 18 361.7 by the same applicant, the image of the Slide with a suitable detector, e.g. B. a television camera, scanned

The application P 24 42 795.0 of the same applicant describes a device suitable for such a device Focus.

For counting and classifying the individual blood cells each individual cell must be searched for, located and set one after the other. Creating a Device suitable for this purpose is the object of the present invention.

This object is achieved by the device of the invention in the characterizing part of the claim 1 resolved

In operation of the device, an object on a slide is brought into position for opening an energy converter by a logic circuit receiving signals from light detectors. A rotating mirror successively reflects parts of the optical image of the slide to one of the light detectors. The logic circuit generates the control signals required to adjust the slide. If no object z. If, for example, no blood body is found, the logic circuit generates a signal which adjusts the slide in the y direction, perpendicular to the scanning direction, whereupon another field of view can be scanned.

A second light detector receives light at the beginning of each scan and generates one into the logic circuit entered synchronization pulse. If a cell is detected, the logic circuit compares the detection time with the time of the synchronization pulse and generates direction signals, which indicate in which direction the slide must be moved along the x-axis in order to move the cell in to center the field of view opening.

The F i g. 1 shows the optical part of an arrangement for scanning and counting cells; z. B. the leukocytes, the blood smear on a slide 10. The light emitted by a light source 12 passes through a lens 14, is reflected by the mirror 16 and falls over a converging lens 18 and after passage through the slide 10 onto an objective 20. A first beam splitter 22 reflects about 40% of the light into the automatic focus and cell detection system of the invention. The rest of the light is through mirror 24.26 in A scanning and analyzing arrangement is directed. The image of a cell of the slide falls through an opening 28 onto a relay lens 30, into an optical preprocessor 32 and compensator 34, and is taken from a television camera 36 recorded, the electrical output signals are digitally processed; see the Registration P 24 18 361.7 by the same applicant.

The first light part of the beam splitter 22 strikes a rotating multifaceted mirror 38, which part on the light detectors 42, 44 for an automatic focusing device after registration P 24 42 795.0 by the same applicant and a narrow one Part of the light detector 40 forming part of the device according to the invention is reflected. The light detector 40 generates a light absorption proportional to the scanned location of the slide Output signal which is amplified by the pulse shaper circuit 46 and sampled for peaks. These Switching results in detection pulses which indicate presence when signals exceed a threshold value a cell on the slide.

A second light source 48 is focused on the rotating mirror 38. The focused light is applied an adjustable second light detector 50 in a specific position and specific time relationship at the beginning of the scanning of the mirror. The light detector 50 then generates the start of the scan by a mirror facet denoting synchronization signal.

On the basis of the detection and synchronization pulses, a logic circuit 52 determines whether the relevant Object is located in the field of view of one of the scanning segments and if so, like the carriage must be moved to center the object in the opening 28. When sweeping the field of view through the facets of the rotating mirror, the logic circuit generates one of four possible signals. Will If no object is encountered, a standard switching signal is generated and the stepping motor 54 switches the Slide by one step in y-direction; a new field of view can now be scanned. The progression one step per mirror facet is continued until the detection detector 40 encounters an object and then generates a direction signal. This indicates whether the object is also stepping through the x-direction progressive servomotor 56 must be shifted to the left or to the right. The movement will continued until the logic circuit emits an object centering signal that stops the movement. This in The object that is now centered on the opening 28 can then be detected by the camera 36.

A digital computer that is present in the overall device for blood testing can also be used to regulate the settings can be used. The signals explained above can then be entered into the computer will. For the sake of simplicity, however, the invention is shown in FIGS. 2A-D only for control by the Logic circuit explained. The picture of a slide loaded with a blood smear shows the respective Position of the object, e.g. B. a blood body 58 to the opening 28 in the scanned field of view, which hatches and so can be shown because the image in the opening 28 is parfocal with that of the mirror 38 scanned image is.

In a first scan, FIG. 2A, is evidence negative by detector 40, the logic circuit generates the standard switching signal, the slide becomes switched one step in y-direction. This will be done with the next scan according to FIG. 2B repeated. In the Position of the F i g. 2C, the detection detector 40 generates the presence of a blood body in the field of view indicating signal. The logic circuit determines the position of this blood body to the left of the opening 28 and generates a directional signal that moves the slide in the ^ direction to the right until the blood cells reach the in the F i g. 2D shown centered position in the opening 28 has assumed

The logic circuit is shown in FIGS. 3A-C shown in more detail. At the beginning of the scanning by a mirror facet, the flip-flop 60 is triggered with a pulse from the synchronization detector 50 set. If there is more than one synchronization pulse, this occurs as a result of noise interference jumps only through the first impulse. This triggers the multivibrator 62. By setting the The opening to the binoculars of the observation set can be adjusted for a monostable period of time. The multivibrator 62 in turn triggers the multivibrator 64, which generates a pulse of a certain width, the flip-flop

66 sets and the oscillator 68 turns on. The generated Clock pulses are fed into a multivibrator 70. This generates pulses of a certain width that go into the Binary counter 72.74 are given. The output counts are deciphered through gates 76,78, where 5 each scan line is divided into 60 equal increments. In the middle of the scan, a central pulse is generated an end pulse is generated at the end. To generate the center pulse, the counter values are thus entered into gate 76 given that its output increases when the counters 72, 74 receive the 29th clock pulse. The 30th clock pulse goes through gate 80. This is the center impulse. Accordingly, the output of gate 78 increases at the 59th clock pulse. The 60th clock pulse goes through gate 82 and is the end pulse. This final impulse represents the Füp-Fiops 60.66 µm, which turns off the oscillator. It also resets the counters 72.74.

If a detection pulse occurs during the scan, it goes through the AND gate 84 and the converter 86 and sets the detection flip-flop 88.

If a detection pulse occurs together with the center pulse on, the latter goes through the AND gate 94, which is opened by the detection pulse from gate 84 became. The output pulse from gate 94 goes through transducer 96 and sets flip-flop 98 for centering one, the AND gate 100 opens, whereupon the end pulse passes through and the pulse for centering the Object generated

If a detection pulse occurs during the scan but does not coincide with the central pulse, in this way a direction signal is generated which indicates the direction of movement required to center the detection pulse A switching register with the flip-flop 102 and the flip-flop 104 determines whether the detection pulse occurs before or after the center pulse The flip-flop 102 is set from the beginning and from Center pulse reset and after the occurrence of the detection pulse before the center pulse the setting status transferred to the flip-flop 104. If the detection pulse occurs after the central pulse, a Transfer reset status from flip-flop 102 to flip-flop 104.

After the occurrence of a detection pulse, the end pulse goes through the AND gate 106 and queries the AND gates 108 and 110. If it occurs before the center pulse, flip-flop 104 is set so that the connection to gate 110 is high, the pulse from gate 106 is allowed through and a directional signal in the direction of + χ (to the right) is generated Center pulse on, the flip-flop 104 is reset and the converter 112 emits a high signal! zuir. Gate 108, the impulse from gate 106 is allowed through and generates a directional signal in the direction - * (to the left). If the scanning remains without a detection pulse, the flip-flops 88, 98 are nevertheless reset during the end pulse, and the AND gate 92 is opened via the OR gate 90, and the end pulse passing through it generates a standard advance signal.

A priority circuit allows only one of the signals cell centering signal, direction signal, standard advance signal develop. The highest priority is given to the cell centering signal. When setting the Flip-flop 98, the lower flip-flop output is low and the gate 114 is the detection of flip-flop 88 im Reset state held. As a result, an end pulse cannot go through gate 106 and a directional signal produce. The reset output of flip-flop 98 is low and blocks through OR gate 90 the AND gate 92, so that a standard incremental signal cannot arise.

The direction signals have second priority. If the detection flip-flop 88 is set, the lower one goes Output of the flip-flop via the OR gate 90 to the AND gate 92 and blocks this. Hence it arises no standard incremental signal. Rather, this can only arise if at the end of a scan neither the detection flip-flop 88 nor the cell centering flip-flop 98 is set. In this case the end pulse can go through both gates 90,92 and generate a standard advance signal.

By manually adjusting the multivibrator 92, the center pulse becomes relative to the synchronization pulse postponed. When scanning, the center pulse should, if possible, be at approximately the center of the field of view the time corresponding to the camera 36 occur; this can be achieved by adjusting the multivibrator 62 will. The frequency of the oscillator 68 can also be adjusted accordingly. By lowering the pulse frequency gives the 60-clock pulse train a larger sampling range, while increased frequency the Scanning range shortened.

In addition 5 sheets of drawings

Claims (1)

Patent claims: 1. Arrangement for the analysis-compatible setting of objects on microscopic slides, the optical characteristics of which are converted into electrical signals, characterized in that that projection means the optical image of the slide onto which this is converted into electrical signals transforming energy converter (36) and throw on a rotating mirror (38), which in turn Throws part of the optical image onto a light detector (40), at the output of which a pulse shaper (46) is connected which generates a detection pulse when an object is present, a second one Light detector (50) sends a synchronization pulse when the rotating mirror is positioned in a predetermined beam position generated, and a logic circuit processing the synchronization and detection pulses (52) is provided for dealing with the possible situations