JPH0449903B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for electronically counting and analyzing particles using an aperture, and particularly for counting and analyzing particles when a plurality of particles coexist within an aperture. The present invention relates to a method for correcting errors in and an apparatus therefor.

Particle analyzers that utilize apertures are well known and are disclosed, for example, in US Pat. No. 2,656,508. The aperture of such an analyzer may be a tiny scanning aperture that allows single particles to pass through at a very high rate of 1000 particles per second or more for detection, counting, and analysis of these particles; It forms the scanning area or the detection area. In practice, the physical parameters of scan aperture and particle concentration often result in the coexistence of two particles within such a scan region. Therefore, if two or more particles are located in the detection area at virtually the same time, they will be detected, counted and analyzed as one particle.

Correction for counting errors caused by such coexistence of particles can be accomplished in various ways. One method is for the operator to refer to a coexistence correction chart representing appropriately error-corrected counts for a large number of selected counts obtained by a counting device. While this provides accurate results, this method is time consuming and does not allow for fully automatic recording and processing of error correction counts.

Other methods have been developed to electrically connect the actual counts or to obtain the actual counts and then provide error-corrected counts. US Pat. No. 3,626,164 (US Patent Classification 235/151.3) discloses a circuit that adds a certain count to a detected count to generate a corrected count that is very close to the true particle count. U.S. Patent No. 3936740 (U.S. Patent Classification 324/
71CP) discloses a circuit for digitally delaying pulses received from a Couter-type aperture. U.S. Patent No. 3,949,197 (U.S. Patent Classification 235/92PC) statistically corrects the counting pulse train of detected particles so that the actual random increase or decrease of coexisting particles does not ultimately result in a counting error. A circuit is disclosed.
Also, U.S. Patent No. 4009443 (U.S. Patent Classification 328/
11) discloses a circuit that changes the time period for counting particle pulses. There are other examples of compensating for counting errors due to coexisting particles within the range of the Coulter aperture, but all of these belong to the above-mentioned US patent classification.

Therefore, coexistence (coincidence) correction of particle counts obtained around the aperture is achieved by manipulating electrical signals obtained from the aperture based on some statistical theory. No attempt has been made to directly determine the point at which errors caused by the coexistence of multiple particles within an aperture coexist.

Coexistence of particles within the aperture not only leads to counting errors, but also leads to errors in analyzing other parameters such as particle volume per particle. The volume of a particle can be analyzed by the amount of change in current flowing through the aperture as the particle passes through the aperture. When two particles coexist within an aperture, the amount of current flowing through the aperture changes differently from the change in the amount of current when a particle passes through the aperture alone. This introduces an error in the determination of particle volume, and it is necessary to correct for such error in order to determine the true particle volume. Until now, no attempt has been made to directly determine the point at which an error caused by the coexistence of particles exists.

Therefore, a method and apparatus for directly measuring the presence of particles within an aperture would be very advantageous. The results of this direct measurement can be used for various purposes, such as correcting data containing errors due to particle coexistence or determining the point in time when valid data exists, as required.

Therefore, the present invention provides a method for correcting coexistence errors occurring in parametric data from particles obtained by a particle analyzer of the type that generates parametric data. The parametric data represents at least one particle analysis parameter, and the coexistence error is introduced into the one data when the data is measured, and the coexistence error is such that the length of the measurement aperture as the particle passes through the measurement aperture. A coexistence error correction method in which the correction is performed substantially at the time when a coexistence error occurs in the one parametric data, the method comprising: A. Generating the one piece of parametric data in response to a measurement along the length of the aperture when at least one particle passes through the length of the measurement aperture,
A step in which it is not possible to distinguish whether particles coexist within the aperture; B. A particle detection step of detecting the presence of individual particles within the aperture in a direction other than the length direction of the aperture; C. D. generating a detection signal in response to detecting the presence of individual particles within the particle; The present invention provides a coexistence error correction method characterized by comprising: a modulation step of modulating the trick data to obtain corrected parametric data free of the coexistence error.

Furthermore, the present invention provides an apparatus for correcting coexistence errors occurring in parametric data from particles obtained by a particle analyzer that generates parametric data, wherein one of the parametric data represents at least one particle analysis parameter, and the coexisting error is introduced into the one data during measurement of the data, and the coexistence error is at least in the longitudinal direction of the measurement aperture as the particle passes through the measurement aperture. A coexistence error correction device that performs the correction at a point in time when a coexistence error substantially occurs in the one parameter data as caused by the coexistence of two particles, the correction device comprising: A at least 1 The means for generating the one piece of parametric data in response to measurement in the length direction of the aperture when the particles pass in the length direction of the measurement aperture,
B. means that cannot distinguish whether particles coexist within the aperture; B. means for detecting the presence of individual particles in a direction other than the length direction of the aperture; particle detection means for generating a detection signal in response to the detection; C. modulating the one parametric data in response to the detection signal after the generation of the one parametric data and the detection signal; , a correction means for obtaining the corrected parametric data free of the coexistence error;

Additionally, the invention provides for a flat beam of radiant energy to pass through the aperture at right angles to the direction of particles flowing through the aperture. Individual particles passing through the flat beam change the distribution of radiant energy exiting the apertured flow chamber sufficiently to generate an electrical detection signal in response to this change. The dimensions of the flat beam within the aperture are such that the beam covers the entire cross-section of the aperture so that the beam can detect particles one by one.

The detection signal is then used to correct for coexisting errors in data obtained from the aperture by means other than a beam of radiant energy, such as by conventional aperture detection principles, as desired. For example, a single detection signal appearing during the duration of an electrical volume signal indicates that there are no coexisting particles within the aperture, and thus indicates that the volume signal is a valid signal. The presence of two or more detection signals during the period of volume signal generation indicates that coexisting particles are present within the aperture and the volume signal is erroneous. Essentially, the present invention aims to obtain effective data by reducing the cross-section of the aperture as an optical detection area and increasing the lengthwise area of the aperture.

The invention will be explained below with reference to the drawings.

In FIG. 1, a particle analyzer is generally designated by the reference numeral 10. The device includes a flow chamber 12, as is well known, having an aperture 14 between an inlet chamber 16 and an outlet chamber 18. Particles to be analyzed are from particle source 20
Aperture 14 in flow chamber 12 from
and to the particle sink 22. Sheath fluid is also passed from a sheath fluid source 24 through the aperture 14 to a sheath fluid sink 26 . The sheath fluid helps maintain particles from the particle source 20 in the axis of the aperture 14.

The particles and sheath fluid can be passed from their respective sources through the flow chambers to their respective sinks by any desired means, such as tubes or other conduits. Thus, lead 28 represents a means for transporting particles from source 20 to flow chamber 12, lead 32 represents a means for transporting particles from flow chamber 12 to particle sink 22, and lead 30 represents a means for transporting particles from flow chamber 12 to particle sink 22, and lead 30 represents a means for transporting particles from flow chamber 12 to particle sink 22, and lead 30 represents a means for transporting particles from flow chamber 12 to particle sink 22. Means for conveying sheath fluid from fluid source 24 to flow chamber 12 includes:
Lead 34 represents a means for conveying sheath fluid from flow chamber 12 to sheath fluid sink 26 .

The particle analyzer also includes a pair of electrodes 36 and 38 located in the inlet and outlet chambers of flow chamber 12, respectively.
This pair of electrodes is connected to a volume detection circuit 40 via lead wires 42 and 44. Volume detection circuit 40
generates an electric current along the length of the aperture 14 through leads 42 and 44 and electrodes 36 and 38. As is well known in aperture-based particle analyzers, particles passing through the aperture 14 change the current flowing through the aperture, and this current change can be measured by the volume sensing circuit 40, and particles passing through the aperture 14 from this point change the current flowing through the aperture. An electrical signal can be obtained indicative of particle volume or other parameters. A signal indicating the volume of particles passing through the aperture 14 is output to the lead wire 43. However, the volume signal output to this lead wire 43 includes coexistence errors that have been corrected in advance by various means as described above.

According to the present invention, this coexistence error is corrected by passing a flat beam of radiant energy through the optically transparent wall of the flow chamber 12, specifically through the aperture 14 at right angles to the flow direction of the particles passing through the aperture 14. The dimensions of such a flat beam of radiant energy are such that the flat beam extends at least from wall to wall of the aperture and the height of such beam relative to the direction of particle flow is approximately the diameter of the particle flowing through the aperture. The dimensions shall be equal. If no particles pass through the light beam in aperture 14, the radiant energy beam passes through the opposite wall of the flow chamber and hits the beam stop. The radiant energy of the beam that is deflected or diffracted by imperfections in the flow chamber wall or sheath fluid also exits the flow chamber and is bent beyond the beam stop, resulting in light Hits the surface of the sensor. Accordingly, the optical sensor generates a detection signal indicative of the amount of radiant energy impinging on its surface.

If no particles pass through the aperture 14 and the flat beam of radiant energy, the detection signal from the optical sensor assumes a DC level value, ie, a constant value. When a particle passes through the aperture 14 and the flat beam, the particle diffracts or deflects the light from the flat beam.
Change the distribution of radiant energy hitting the surface of the optical sensor. When the radiant energy distribution changes like this, the value of the detection signal from the optical sensor changes, and this detection signal comes to exhibit a pulse-like alternating current value.

The pulses of the detection signal are used to indicate the presence of individual pulses at the location of the flat beam within the aperture 14. The flat beam within the aperture is dimensioned as described above, so that each pulse of the detection signal indicates the presence of a single particle within the aperture. Therefore, multiple pulses of the detection signal generated during the period when a single molten signal is output to the lead wire 43 will indicate an erroneous volume value due to the coexistence of particles. Thereafter, such erroneous volume signals can be used to ignore them if desired to eliminate coexisting errors when adding the resulting particle volume signals.

Returning to FIG. 1, a radiant energy source 50, such as a laser, generates a coherent radiant energy beam 52, such as light. Such beam 5
2 passes through beam shaping optics 54, which shapes beam 52 into a flat beam 56 having the desired dimensions as described above. Then the flat beam 56
is the optically transparent wall 58 of the flow chamber 12.
and 60, passing through the aperture 14. The radiant energy leaving the flow chamber 12 is
As shown, there are two beam configurations: a primary beam consisting of dispersion or scattering of light, such as by diffraction or polarization of the flattened beam 56, and a zero-order beam of the flattened beam 56 itself. Such a zero order beam, of course, consists of the radiant energy of the flattened beam 56 that is not dispersed or scattered by the flattened beam 56. Radiant energy exiting flow chamber 12 is directed to optical sensor 66 (FIG. 1), which includes a zero order beam stop 68 and a face 70 as shown in FIG. The zero order beam is directed to beam stop 68, where it is completely absorbed. The primary beam is directed mostly toward the face 70 of the optical sensor 66, and the radiant energy of the primary beam is used to generate a detection signal on a lead 72. Such a detection signal is sent to the coexistence error correction circuit 74.
supplied to Thereafter, the output of the coexistence error correction circuit 74 is supplied to a particle analyzer 78 via a lead wire 76.

Although FIG. 2 is an enlarged cross-sectional view of a portion of the flow chamber 12, hatching on the transparent walls 58 and 60 of the flow chamber 12 is omitted for clarity of the drawing. The particle source tube 80 is 82,
Particles such as 84, 86 and 88 are fed into tube 90 through inlet chamber 16, aperture 14 and outlet chamber 18 in the direction indicated by arrow 92. Sheath fluid from sheath fluid source 24 also flows through inlet chamber 16, aperture 14 and outlet chamber 1.
8 to a sheath fluid sink 26. The inlet chamber 16 thus directs the particles to the aperture 14.
A good volumetric signal is obtained from the aperture because it is in fluid communication with the outlet chamber 18 through the aperture 14 with the desired sheath fluid being maintained on the axis of the aperture.

For both mechanical and operational reasons, the aperture size is many times larger than the diameter of the particle to be measured. Therefore, if a large number of particles appear within the aperture 14 at any time, this is known as a particle coexistence phenomenon. An example of the coexistence of such particles is illustrated by particles 84 and 86 coexisting within aperture 14.

As shown in FIG. 2, the thickness of the flat beam 56 along the direction of particle flow indicated by arrow 92 is approximately equal to the diameter of the particle. As shown in FIG. 3, the width of the beam 56 is approximately equal to the width of the aperture 14. That is, beam 56 extends approximately from wall to wall of aperture 14. In this way, particles within the aperture 14 are ensured to be ejected.

Although the example of FIG. 3 shows an aperture with a rectangular cross section, the present invention can also use an aperture with a round cross section, as will be described later.

Since the height (thickness) of the flat beam 56 is approximately equal to the diameter of each individual particle, each individual particle passing through the aperture 14 is detected one by one even if these particles are closely spaced from each other. be done. Therefore, the flat beam 56 and the optical sensor 66
In addition to determining the volume of particles passing through the aperture 14 along its length, it provides a means by which particles passing through the aperture 14 can be detected one by one.

The upper waveform graph 94 in FIG. 5 shows the volume signal obtained from the volume detection circuit 40.
The lower waveform graph in FIG. 5 shows the pulses of the detection signal output by the optical sensor 66. The first pulse, shown at waveform 96, is the light beam 56.
The pulses corresponding to particles 86 of FIG. Note that FIG. 5 does not accurately show the relative values of the waveforms 94, 96, and 98, but merely shows the relative time relationships in which the waveform signals are generated.
Thus, two pulses of the detection signal occurring during one period of volumetric signal generation can be used to indicate the coexistence of particles within the aperture 14.
If only one detection signal occurs, as represented by waveform 96, it indicates that only a single particle is present within aperture 14. In this latter case, particles 84 in FIG.
4, which does not coincide with the particle 86, and therefore, in this case, the waveform signal 98 will not be generated during the generation of the volume signal waveform 94. Dashed waveform 99 in FIG. 5 shows the expansion of the volume signal when particles 84 and 86 coexist within the aperture.

FIG. 4 shows an example of an electrical circuit for modulating a coexisting particle volume signal containing unprocessed data from the volume detection circuit 40 to obtain corrected data free of the coexistence error. Advantageously, this circuit uses pulses of the detection signal from the optical sensor to gate the passage of valid volume data to the particle analyzer 78.

Leads 42 and 44 from electrodes 36 and 38
are shown as twin inputs to volumetric signal amplifier 100. The output of the amplifier 100 is originally an output signal output from the volume detection circuit 40 to the lead wire 43. This signal has a substantially smooth waveform, as shown by waveform 94 in FIG. A peak detection and holding circuit 102 and a comparator 10 configured as a noise discriminator detect such a volume signal.
4 and one input terminal of 4. The other input terminal of comparator 104 connects to a variable resistor VRI that provides a noise-limited voltage level.

The value of the signal appearing on the lead wire 43 is the variable resistance.
Once the noise limit selected by VRI is exceeded, comparator 104 sends the corresponding signal to lead 1.
This signal, hereinafter referred to as the "conversion signal", is output to two D-type flip-flops 108 and 1.
10 and an analog/digital converter 112. Analog/digital converter 112
The output of such transducer 1 appears on lead 76.
12 is connected to peak detection and holding circuit 102 by leads 114 and 116. Lead wire 11
4 is a signal called “enlarger pulse” as an analog/
A digital (A/D) converter 112 is provided, and a lead 116 provides a "clear" signal to the peak detect and hold circuit 102.

The signal supplied from the optical sensor 66 to the coexistence error correction circuit 74 via the lead wire 72 also has a smooth waveform. This detection signal is amplified by an amplifier 118 and then supplied via a lead wire 120 to one input terminal of a comparator 122 configured as a noise discriminator. The other input terminal of comparator 122 is connected to a variable resistor VR2 that provides a noise-limited voltage level.

When the signal value appearing on lead 120 exceeds the noise threshold level, comparator 122 outputs a corresponding signal on lead 124. The signal appearing on this lead wire 124 corresponds to the detection signal waveform shown at the bottom of FIG. These signals or pulses are applied to the clock input terminals of flip-flops 108 and 110. flip flop 1
The 10 Q output is supplied to both the A/D converter 112 and the coexistence meter 128 via a lead 126.

In operation, amplifiers 100 and 118 are used to generate logic signals having valid levels. Both the volume and detection signals from amplifiers 100 and 118 are compared to a noise threshold voltage level to distinguish them from noise. Comparators 104 and 12
The output signals of the discriminators, denoted as 2, all have a square wave shape, and the duration of these signals corresponds to the length of the pulses supplied to each discriminator. The output of comparator 104 is connected to two D-type flips.
Used to enable flops 108 and 110. flip-flop 108 and 1
10 is cleared when the output pulse from comparator 104 disappears. Because of this, both flip
The Q output of the flop goes to a logic zero "0" state. During the duration of the volume signal, the detection pulse from amplifier 122 clocks two flip-flops simultaneously. When both flip-flops are clocked in this manner, flip-flop 108
The Q output of the flip-flop 110 is in the logic 1 state, and the Q output of the flip-flop 110 is in the logic zero state, 0.
Stay in state. If the second pulse occurs in the detection signal during the generation period of the volume signal, lead wire 1
Q of flip-flop 110 connected to 26
The output is also in the "1" state of logic 1. As flip-flops 108 and 110 operate, the volume signal is detected and held to obtain the volume of the particle. The falling edge of the output signal of the volumetric signal discriminator, the "conversion signal," instructs the A/D converter 112 to convert the stretched pulse from the peak detect and hold circuit 102 to a digital value. When the falling edge of the “conversion signal” occurs, lead 12
When the "conversion inhibit signal" at 6 is at a high level, i.e., in a logic 1 "1" state, the A/D converter 112 does not digitally convert the enlarged pulse, and therefore the A/D converter 112 does not digitally convert the enlarged pulse. 112 generates a "clear signal" on lead wire 116 to clear the signal held in peak detection and holding circuit 102. When the falling edge of the “conversion signal” occurs,
When the signal on lead 126 is at a low level, i.e., a logic zero "0" state, A/D converter 112 converts the sensed and held value by circuit 102 to a digital value and outputs it. A "clear signal" is generated on the lead wire 116. Lead wire 1
The signal appearing at 26 can also be fed to a coexistence rate meter 128 to total the number of coexistences.

Therefore, coexistence correction circuit 74 can be considered to gate the volume signal to A/D converter 112 only if one detection pulse occurs during the duration of the volume signal.

In a particular embodiment of the invention, the particles to be analyzed have a diameter of about 1 to 20 micrometers. The aperture flow along the particle flow direction is about 76 micrometers, and the flat beam height along the particle flow direction is about 5 micrometers.

As previously mentioned, optical sensor 66 includes a zero order beam stop and a sensor for first order dispersion. Such a sensor may be as disclosed in US Pat. No. 4,038,556. Such a sensor may also generate a detection signal by detecting energy changes in the zero-order beam caused by particles passing through the flat beam 56, while ignoring the scattered light of the first-order beam.

Although FIG. 3 shows an aperture having a rectangular cross section, the same effect can be achieved even if the cross section of the aperture 14 is circular as described above. The reason for this is that the electrical detection signals generated in response to particles passing through the flat beam 56 are transferred to the flow chamber 1.
This is because such a detection signal is not a function of the absolute amount of light hitting the optical sensor. In practice, the pulses of the detection signal are due to changes in the light distribution impinging on the optical sensor, and therefore the reflectivity of the sheath fluid, the optical clarity of the fluid damper, and the cross-sectional structure of the aperture are essentially irrelevant to the detection signal. be.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of a particle detection and analysis device utilizing the device according to the invention; FIG. 2 shows an aperture portion in a flow chamber and a particle passing through the aperture at right angles to the direction of the particles flowing through the aperture; FIG. 3 is an enlarged top view of the flow chamber; FIG. 4 is a block diagram showing an example of a circuit that can be used in the present invention for data correction for coexistence errors; FIG. 5 is a waveform diagram showing the time relationship between a detection signal and a volume signal generated by the coexistence of two particles passing through an aperture. 10... Particle analyzer, 12... Flow chamber, 14... Aperture, 16... Inlet chamber, 18... Outlet chamber, 20... Particle source, 2
2... Particle sink, 24... Sheath fluid source, 26
... sheath fluid sink, 28-34 ... conduit, 3
6, 38...electrode, 40...volume detection circuit, 4
2, 43, 44...Lead wire, 50...Radiant energy source, 52...Radiant energy beam, 54
... Beam shaping optical system, 56 ... Flat beam, 5
8, 60... Flow chamber wall portion, 66... Optical sensor, 68... Beam stop, 70... Face portion, 72... Lead wire, 74... Coexistence error correction circuit, 78... Particle analyzer, 80... ...particle source, 8
2-88...Particle, 90...Tube, 100...
... Volume signal amplifier, 102 ... Peak detection and holding circuit, 104 ... Volume signal comparator (noise discriminator), 108, 110 ... Flip-flop,
112...A/D converter, 118...Detection signal amplifier, 122...Detection signal comparator (noise discriminator), VR1, VR2...Variable resistor, 128...Coexistence rate measuring meter.

Claims (1)

[Scope of Claims] 1. In a method for correcting coexistence errors occurring in parametric data from particles obtained by a particle analyzer of a type that generates parametric data, one of the parametric data The parametric data represents at least one particle analysis parameter, and the coexistence error is introduced into the one data when the data is measured, and the coexistence error is such that the length of the measurement aperture as the particle passes through the measurement aperture. at least 2 in the horizontal direction
A coexistence error correction method in which the correction is performed at a point in time when a coexistence error occurs substantially in the one parameter data, the method comprising: A coexistence error caused by the coexistence of at least one particle; In the step of generating the one piece of parametric data in response to a measurement in the length direction of the aperture when particles pass through the length direction of the measurement aperture,
A step in which it is not possible to distinguish whether particles coexist within the aperture; B. A particle detection step of detecting the presence of individual particles within the aperture in a direction other than the length direction of the aperture; C. D. generating a detection signal in response to detecting the presence of individual particles within the particle; A coexistence error correction method comprising: a modulation step of modulating trick data to obtain corrected parametric data free of the coexistence error. 2. The method of claim 1, wherein the step of detecting particles comprises passing a beam of radiant energy through the aperture at right angles to a first direction in which particles pass through the aperture. Coexistence error correction method. 3. Coexistence according to claim 1 or 2, characterized in that the radiant energy beam is flattened so that all of the particles passing through the aperture pass through the flattened beam. Error correction method. 4. The height of the radiation beam in the first direction is at least approximately equal to the diameter of the particle, and the width of the beam is approximately equal to the width of the aperture. Coexistence error correction method described. 5. The particle detection step includes the step of optically detecting radiant energy received from the radiant energy beam that has passed through the aperture, and the optical detecting step includes the step of optically detecting radiant energy received from the radiant energy beam that has passed through the aperture, and the optical detecting step includes the step of optically detecting radiant energy received from the radiant energy beam that has passed through the aperture, The coexistence error correction method according to claim 1, further comprising the step of generating the detection signal in response to changing the received radiation energy distribution. 6. The optical detection step includes the step of providing a beam stop that receives almost all of the zero-order beam of the radiant energy beam itself and a face portion that receives almost all of the primary beam consisting of dispersed radiant energy of the radiant energy beam. A coexistence error correction method according to claim 5, characterized in that: 7. Coexistence error correction according to claim 6, wherein the detection signal generation step includes a step of generating a pulse in response to particles passing through the radiant energy beam. Method. 8. The step of modulating the parametric data includes a gating step of gating each parametric data in response to the detection signal so that correct parametric data free from the coexistence error is passed. A coexistence error correction method according to claim 1, characterized in that: 9. said detection signal includes pulses representative of individual detected particles, and said step of modulating said parametric data detects and holds the value of each parametric data and detects the detection occurring during the generation of each parametric data. counting the number of signal pulses, the gating step gating each of the detected and held parametric data in response to the number of detection signal pulses counted during the generation period of each of the parametric data; Claim 8 includes the step of
The coexistence error correction method described in Sec. 10. The coexistence error correction method according to claim 1, wherein each parametric data is modulated in response to the detection signal immediately after the respective parametric data and detection signal are generated. 11. In a device for correcting coexistence errors occurring in parametric data from particles obtained by a particle analyzer that generates parametric data, one of the parametric data has at least one represents a particle analysis parameter, and the coexistence error is introduced into the one data when measuring the data;
Furthermore, when the particle passes through the measurement aperture, it is assumed that at least two particles coexist in the length direction of the measurement aperture, so that the correction essentially causes a coexistence error in the one parametric data. A coexistence error correction device for performing a coexistence error correction at a time point, wherein the correction device: The means for generating the one piece of parametric data,
means 40, 42, 44 that cannot distinguish whether particles coexist within the aperture;
B. Particle detection means 56 for detecting the presence of individual particles other than along the length of said aperture and generating a detection signal in response to detecting the presence of individual particles within said aperture; C. After the one parametric data 42 and the detection signal 72 are generated, the one parametric data 42 is generated in response to the detection signal 72.
A coexistence error correction apparatus comprising: a correction means 74 for modulating the parameter data 76 to obtain corrected parameter data 76 free of the coexistence error. 12. The particles pass through the aperture in a first axial direction of the measurement aperture, and the particle detection means includes a beam of radiant energy passing through the aperture at right angles to the first direction. A coexistence error correction device according to claim 11. 13. Claim 12, characterized in that the radiant energy beam is a flat beam, and the dimensions of the beam are such that all of the particles passing through the aperture always pass through the flat beam. coexistence error correction device described in . 14 the beam of radiant energy is a flat beam, the dimensions of the beam are such that all of the particles passing through the aperture pass through the flat beam;
13. The coexistence error correction device according to claim 12, wherein the height in the direction is at least approximately equal to the diameter of the particle, and the width of the beam is approximately equal to the width of the aperture. 15. The particle detection means includes optical sensor means for receiving radiant energy from the radiant energy beam passing through the aperture, and the sensor means detects the received radiant energy distribution by the passage of the particles through the radiant energy beam. 15. The coexistence error correction device according to claim 12, wherein the detection signal is generated in response to a change in the coexistence error correction device. 16 the particles passing through the radiation beam act as a primary beam of radiant energy dispersed from the beam and a zero-order beam consisting of the radiant energy itself of the radiation beam, and the optical sensor means 16. The coexistence error correction device according to claim 15, further comprising a beam stop that receives almost all of the secondary beam and a face portion that receives almost all of the primary beam. 17. The coexistence error correction device of claim 15, wherein the detection signal includes a pulse generated in response to a particle passing through the radiant energy beam. 18. A claim characterized in that the correction means includes gate means for gating each parametric data in response to the detection signal and passing the corrected parametric data free of the coexistence error. The coexistence error correction device according to item 11. 19. The correction means includes gate means for gating each parametric data in response to the detection signal to allow the corrected parametric data free of the coexistence error to pass, and the detection signal a detection/holding means that includes a pulse representing a particle and in which the correction means detects and holds the value of each parametric data; and a counting means that counts the number of detection signal pulses occurring during a generation period of each parametric data. and wherein the gating means gates each parametric data from the detecting and holding means in response to the number of detection signal pulses counted by the counting means during the generation period of the parametric data. A coexistence error correction device according to any one of claims 11 to 17. 20 A patent characterized in that the gate means passes each parametric data from the detection and holding means in response to one detection signal pulse counted during the generation period of each of the parametric data. A coexistence error correction device according to claim 11. 21. The gate means passes each parametric data from the detection and holding means in response to the counting means for counting one detection signal pulse counted during the generation period of each parametric data. A coexistence error correction device according to claim 11, characterized in that: 22. Claims 11 to 21, characterized in that, immediately after the respective parametric data and the detection signal are generated, the correction means can modulate the parametric data in response to the detection signal. The coexistence error correction device according to any one of .