CN113552048B - Particle counting method - Google Patents
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- CN113552048B CN113552048B CN202110845099.5A CN202110845099A CN113552048B CN 113552048 B CN113552048 B CN 113552048B CN 202110845099 A CN202110845099 A CN 202110845099A CN 113552048 B CN113552048 B CN 113552048B
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Abstract
The invention provides a particle counting method, which comprises the following steps: calibrating a photoelectric detection component; calibrating threshold voltages corresponding to particles with different particle diameters; and setting a comparison voltage value adjusted by a potentiometer of the particle channel based on the threshold voltage, comparing the output voltage of the photoelectric detection part with the comparison voltage value through a comparator, distinguishing the particle size and counting the number. The comparison voltage value of the comparator is regulated through the potentiometer, so that counting can be efficiently and accurately finished, and the cost is low; the particle counter is calibrated and then metering is carried out, the steps are concise, the deviation range of the final metering result is greatly reduced, the standard counter and the manual operation level are not relied on, the metering efficiency is high, the reliability is good, the implementation is easy, and the further popularization and the development of the metering technology are facilitated.
Description
Technical Field
The invention belongs to the technical field of metering, and particularly relates to a particle counting method for metering by adopting an optical particle counter.
Background
The conventional particle counting method is based on the Mie scattering principle, and a light scattering type laser particle counter is adopted to measure the number and the particle size distribution of dust particles in a unit volume in a clean environment. Particle counting is widely applied to industries such as medicines, precision machinery, microorganisms and the like, and is also one of main metering works of authorities such as epidemic prevention stations, disease control centers, quality supervision centers and the like. With the gradual implementation of the GMP authentication system and the deep application of particles in aerosol in disease transmission analysis, the influence of the particle counting method is also greater and greater. However, the accuracy, reliability, consistency of existing particle counting methods do not fully meet the application requirements, one of the important reasons being that existing particle counters are not fully calibrated or are not effectively calibrated before they are put into use. Before the conventional particle counting method is implemented, a common inspector adopts a standard particle counter to calibrate, and manually blindly adjusts the comparison voltages of comparators of different particle channels to enable the particle channel count to be approximately the same as the standard particle counter. And then metering is implemented through one or more particles with unknown particle size in a working area, the comparison voltage of a comparator is required to be manually adjusted for multiple times, the comparison with a standard counter is dependent on frequent comparison, the uncertainty is high, the whole particle counting efficiency is low, the reliability is difficult to improve, and the requirement of metering work cannot be met.
Therefore, it is very necessary to study effective and feasible particle counting method to improve the accuracy and reliability of the metering operation, so as to further promote the deep development and wide application of the metering technology.
Disclosure of Invention
The invention aims to solve part, all or potential problems in the prior art, and provides a particle counting method which adopts a particle counter to test the particle size and distribution of airborne dust particles.
For some terms or principles that may be involved in the present invention, the following description is given by way of example and not limitation:
Mie scattering (MIE SCATTERING), an optical phenomenon, is one of the conditions of scattering. When the particle size is close to or greater than the wavelength λ of the incident light, a large portion of the incident light is scattered in the forward and vertical directions, a phenomenon called Mie scattering.
Particle size (particle size): the diameter of a certain kind of scattering particles in air is the diameter of the particle corresponding to the intensity of the scattered light, in [ mu ] m.
Standard counter: and (3) a particle counter which is subjected to national organization comparison and can obtain satisfactory results.
The metering principle of the particle counter in the invention is as follows: a photodetection part is provided, which comprises an optical module and a photodetection module which are arranged in different directions. The working area is formed in the light field output by the optical module, the airflow of particles with certain concentration passes through the working area, the light of single particles scattered by Mie scattering is collected by the Mie scattering collector and then projected onto the photosensitive element of the photoelectric receiving module, and the energy is converted into a voltage pulse signal through the pre-amplifying circuit. The voltage pulse signals are compared through threshold voltages of channels with different particle sizes to distinguish the sizes of the particle sizes and count the number of the particles with different particle sizes.
The invention provides a particle counting method, which adopts a particle counter for counting, wherein the particle counter comprises a photoelectric detection part, a main control board, a comparator and a potentiometer, wherein the comparator and the potentiometer are integrated on the main control board; the counting process comprises the following steps: s1, calibrating a photoelectric detection part; the photodetection member includes: a laser, a photosensitive element and a pre-amplifier circuit; s2, calibrating threshold voltages corresponding to particles with different particle diameters; s3, setting a particle channel according to the particle size, and setting a comparison voltage value adjusted by a potentiometer of the particle channel based on the threshold voltage corresponding to the particle with the particle size; s4, enabling the particle airflow to be detected to pass through a working area of the particle counter, and comparing the output voltage of the photoelectric detection part with the comparison voltage value by a comparator to distinguish the particle size and count the number; the step S1 comprises the steps of calibrating the laser intensity in advance, setting an optical path turning component in a working area, and calibrating the output voltage of the pre-amplifying circuit. The particle counter generally comprises a photoelectric detection component and a counting component, wherein the photoelectric detection component can be divided into an optical module and a photoelectric receiving module in two directions of a working area, namely, an output light beam of a laser in the optical module cannot be projected to the photoelectric receiving module along a light path in one direction. If the photoelectric detection component is to be calibrated effectively, on the one hand, the light intensity of the particle counter in the working area is required to be uniform, and the light intensity of each point in the whole working area is the same, so that the light intensity of the laser light source in the working area needs to be calibrated; on the other hand, the pre-amplifying circuit of the photoelectric detection part must calibrate the electric signal after photoelectric conversion by the photosensitive element. In the step S1, based on the same laser light source, the light path turning parts are arranged to integrally implement calibration, after the laser light intensity is calibrated, the light intensity of the laser light source in a working area meets the preset light intensity requirement, and the light intensity of each particle count is kept to be better consistent. Meanwhile, a laser light source is adopted for calibration, so that the accumulation of calibrated deviation is avoided, and the deviation can be reduced to the greatest extent. The optical path turning element, such as a reflector or a combination of a plurality of reflectors, is used for irradiating the working beam to the photosensitive element for subsequent calibration after turning, and the optical path turning element can be correspondingly arranged in combination with the specific layout of the working area of the particle counter and the photosensitive element to guide the working beam to the photosensitive element. In the step S3, the potentiometer is set based on the threshold voltage to accurately set the comparison voltage values of different particle channels, so that uncertainty of manual blind adjustment is avoided; compared with the counting method of the standard counter, the counting method has the advantages that the efficiency is greatly improved, and the counting result can be intuitively and rapidly obtained.
Before the step S1, shaping the output beam of the laser to obtain a working beam; the optical path structure for beam shaping comprises a lens, and the working beam is a flat-top beam.
The calibrating the laser intensity includes: calibrating the size of the light spot area of the working beam in the working area and the uniformity of light intensity distribution in the light spot; the specific process comprises the following steps: acquiring spot information of the working beam by using a laser spot collector, wherein the spot information comprises a spot image, and evaluating whether the size of a spot meets the requirement or not according to the spot image, and whether the light intensity distribution in the spot is uniform or not; and adjusting the distance between the lens and the laser according to the evaluation result.
The specific process for calibrating the laser intensity further comprises the following steps: and presetting a standard total value of the optical power of the working area, measuring the optical power of the working beam, and adjusting the optical power of the working area to be consistent with the standard total value based on a measuring result. By calibrating the optical power of the working beam, whether the light intensity of the working beam reaches the actual particle counting requirement can be estimated, and the consistency of the optical power of the laser light source after beam shaping is maintained.
Calibrating the output voltage of the pre-amplifier circuit includes: an attenuation sheet is additionally arranged between the light path turning element and the photosensitive element to weaken the light intensity of the light spot irradiated to the photosensitive element; and adjusting the area of the light spot irradiating the photosensitive element through a light spot cutting clamp between the light path turning element and the photosensitive element. Because in some specific applications, the light intensity of the working beam may exceed the light intensity range that the photosensitive element can bear, setting the attenuation sheet can adjust the light intensity of the light spot, so that the risk that the photosensitive element is damaged due to direct irradiation of the photosensitive element by the working beam is effectively avoided. The spot cutting clamp is arranged, so that the spot area with specific requirements can be obtained, the practical application is better combined, and the flexibility of calibration work is improved. The attenuation sheet and the facula cutting clamp can be arranged according to the actual counting working condition and the specifically adopted particle counter, or the attenuation sheet and the facula cutting clamp are arranged, and the method is not limited.
In step S2, the waveform output by the pre-amplifying circuit is collected through particles with a predetermined particle size in the working area, the peak value of the waveform is analyzed in a statistical manner, and the threshold voltage corresponding to the predetermined particle size is marked.
At least 6 predicted particle sizes are included, wherein the predicted particle sizes comprise 0.3 mu m, 0.5 mu m and 1.0 mu m; in step S3, at least 6 particle channels are set, and at least 6 comparison voltage values are adjusted by using a potentiometer.
And carrying out one-time statistical analysis on the peak value of the waveform, writing data obtained by the statistical analysis into a memory of a preset main control board, processing by a processor to obtain the threshold voltage, and giving out a comparison voltage value adjusted by each channel potentiometer.
A virtual oscilloscope is adopted to statistically analyze the peak value of the waveform; the virtual oscilloscope is based on software programmed graphically, including Labview. Virtual oscilloscopes are applications that utilize high-performance modular hardware, in combination with efficient and flexible software, to accomplish various tests, measurements, and automation. Wherein Labview is system engineering software designed specifically for testing, measurement and control applications, and can quickly access hardware and data information.
In the process of calibrating the output voltage of the pre-amplifying circuit, a universal meter is adopted to measure the output voltage of the pre-amplifying circuit; when a plurality of particle counters are adopted for counting, the pre-amplifying circuit of each particle counter is provided with a potentiometer, and the potentiometer is adjusted so that the output voltage of the pre-amplifying circuit of each particle counter is kept consistent and is equal to the design theoretical value of the output voltage of the photoelectric detection part. The multimeter has the advantages of simple operation, easy configuration, low cost and convenient calibration. Based on the calibrated laser light intensity, the design theoretical value of the output voltage of the photoelectric detection component is predictable, the output voltage of the pre-amplifying circuit of each particle counter is regulated to be consistent with the design theoretical value, the output voltage of the pre-amplifying circuit of each particle counter is calibrated, the marked threshold voltage is more reliable, the comparison voltage value can be set more accurately, and the final counting result can be acquired more accurately.
Compared with the prior art, the invention has the main beneficial effects that:
The particle counting method disclosed by the invention is not completely dependent on the existing standard counter for counting, and can be used for efficiently and accurately completing counting by combining the potentiometer with the comparator, so that the cost is low, the efficiency is high, the counting is performed after the same laser light source is continuously calibrated, and the risk of error generation is greatly reduced. Uncertainty of manual operation is avoided. By adopting the counting method, a plurality of particle counters count for a plurality of times, so that the consistency of the obtained results is good; is very favorable for further popularization and development of the metering technology.
Drawings
Fig. 1 is a schematic diagram of a particle counter according to a first embodiment of the present invention.
Fig. 2 is a schematic diagram illustrating a particle counting method according to a first embodiment of the invention.
Fig. 3 is a schematic diagram of calibrating laser intensity according to a first embodiment of the present invention.
Fig. 4 is a schematic diagram of a calibration tool for a photoelectric receiving module according to a first embodiment of the invention.
Fig. 5 is a schematic diagram of calibrating laser intensity according to a second embodiment of the present invention.
Fig. 6 is a schematic diagram of a calibration tool according to a second embodiment of the present invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and fully, and it is apparent that the embodiments described are only some, but not all, of the embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The foregoing and/or additional aspects and advantages of the present invention will be apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings. In the figures, parts of the same structure or function are denoted by the same reference numerals, and not all illustrated parts are denoted by the associated reference numerals throughout the figures, if necessary, for the sake of clarity.
The operations of the embodiments are depicted in the following examples in a particular order, which is presented to provide a better understanding of the details of the embodiments and to provide a thorough understanding of the invention, but is not necessarily a one-to-one correspondence with the methods of the invention, nor is it intended to limit the scope of the invention in this regard.
It should be noted that the flowcharts and block diagrams in the figures illustrate the operational processes that may be implemented by the methods according to the embodiments of the present invention. It should also be noted that in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the intervening blocks, depending upon the objectives sought to be achieved by the steps involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and manual operations.
Example 1
In a first embodiment of the present invention, as shown in fig. 1, the particle counter used in the present embodiment is composed of an optical module for providing a working beam, a working area for detecting, a photoelectric receiving module for receiving and converting an optical signal, a main control board integrated with a processor and a comparator, and a mechanical potentiometer electrically connected with the comparator. Wherein the optical module and the photoelectric receiving module are positioned in two directions of the working area; the working area is typically a photosensitive working area and a Mie scattering collector. The optical module is provided with a laser serving as a laser light source and a power supply component thereof, and the output light intensity of the laser can be adjusted by adjusting the power supply of the laser; in this embodiment, an optical path shaping structure including a plurality of lenses and diaphragms is disposed near an output end of the laser, and gaussian light spots of an output beam of the laser are shaped to obtain a working beam with a flat-top beam, and light spots formed in a working area are flat-top homogenized. The lens is exemplified by a collimating lens, and it should be noted that the optical path shaping structure may be designed according to the practical application requirement or the specific particle counter structure, or may include other optical lenses or optical elements, and is not limited. The light which is emitted by the single particles after passing through the Mie scattering collector is collected by the photoelectric receiving module, and is particularly projected onto the photosensitive element. The photosensitive element of the embodiment is a photodiode, and has small volume, quick response and good reliability. Other photosensitive elements such as phototransistors and the like are used in some embodiments, and are not limited. The energy is converted into a voltage pulse signal through a pre-amplifying circuit of the photoelectric receiving module, and the voltage pulse signal is compared with threshold voltages of channels with different particle sizes to distinguish the particle sizes, so that counting is realized.
In this embodiment, the particle counting method as shown in fig. 2 includes: s1, calibrating a photoelectric detection part; s2, calibrating threshold voltages corresponding to particles with different particle diameters; s3, setting a particle channel according to the particle size, and setting a mechanical potentiometer to adjust a comparison voltage value of the particle channel based on a threshold voltage corresponding to the particles with the particle size; s4, enabling the particle airflow to be detected to pass through a working area, and comparing the output voltage of the photoelectric detection part with a comparison voltage value by a comparator to distinguish the particle size and count the number; in the step S1, the laser intensity is calibrated firstly, then an optical path turning component is arranged in a working area, and the output voltage of the pre-amplifying circuit is calibrated.
In this embodiment, as shown in fig. 3, a laser spot collector is adopted in the process of calibrating the laser intensity, and an example is that a CCD camera with adjustable front and rear positions arranged on a slide rail acquires spot images of a plurality of working beams, and whether the spot size meets the requirement or not is evaluated through the spot images, and whether the light intensity distribution in the spot is uniform or not. And if the optical beam is uneven, adjusting the distance between the lens and the laser in the beam shaping structure in the optical module.
In this embodiment, as shown in fig. 4, the calibration tool in this embodiment uses a mirror as a turning element of the optical path, and an attenuation sheet is further added on the optical path. In the embodiment, a plurality of particle counters are adopted for counting, a universal meter is adopted for measuring the actual output voltage of the pre-amplifying circuit in the process of calibrating the output voltage of the pre-amplifying circuit, the pre-amplifying circuit is provided with a mechanical potentiometer, and the mechanical potentiometer is adjusted so that the output voltage of the pre-amplifying circuit of each particle counter is kept consistent. In this embodiment, the design theoretical value of the output voltage of the pre-amplifying circuit of the photoelectric detection part under the calibrated laser light intensity is equal to that of the photoelectric detection part. The design theoretical value of the output voltage can be obtained through calculation. In general, the calibrated laser light intensity determination shows that the standard value of the photoelectric conversion rate of the photodiode of the particle counter is provided when a photodiode manufacturer leaves the factory, and the design theoretical value of the output voltage can be calculated according to the gain theory of the pre-amplifying circuit. For ease of understanding, for example, it is known that the power of the working beam is 0.8 μW, the photoelectric conversion rate of the photodiode is 0.5A/W, the amplification gain of the pre-amplification circuit is 5000000 Ω, and the output voltage design theory is 2V. When the operation is performed on particle counting, the obtained results of the particle counters are good in consistency, the output voltage of the pre-amplifying circuit is consistent with the theoretical calculated value after being calibrated, and the subsequent counting result analysis reliability is high. The potentiometers used in this embodiment are all mechanical potentiometers. The mechanical potentiometer is a three-terminal mechanical operation rotary analog device and can be used for various electric and electronic circuits. A mechanical potentiometer is a passive device that does not require a power supply or additional circuitry to perform its basic linear or rotational position function. Mechanical potentiometers are very common, inexpensive and readily available. By combining the mechanical potentiometer with the comparator to implement particle counting, the traditional method is changed, the equipment cost of metering work is not increased, the labor cost is saved, and the reliability and consistency of the counting result are improved. The potentiometers used in the embodiments are digital potentiometers, and the applicable potentiometers are selected according to practical application conditions, and are not limited.
In step S2, the waveform output by the pre-amplifying circuit is collected through particles with a preset particle size in a working area of the particle counter for counting, the peak value of the waveform is counted and analyzed at one time, the peak value of the waveform is counted and analyzed by adopting a virtual oscilloscope, data obtained by the counting and analyzing are written into a memory of a preset main control board, and a processor calls the data to calibrate threshold voltages corresponding to each particle size channel, namely voltage values to be adjusted by a mechanical potentiometer of each channel are given. In the embodiment, a Labview acquisition system with a high-speed ADC board card is adopted to acquire waveforms output by a pre-amplifying circuit. For example: the method comprises the steps that particles with the size of 0.3 mu m pass through a working area, waveforms output by a pre-amplifying circuit are collected by Labview, the peak value of each waveform is analyzed in a statistics mode, and then threshold voltages of the particles with the size of 0.3 mu m are marked; the method comprises the steps of collecting waveforms output by a pre-amplifying circuit through particles of 0.5 mu m, carrying out statistical analysis on peak values of each waveform by using Labview, and marking threshold voltages of the particles of 0.5 mu m; and (3) through particles of 1.0 mu m, acquiring waveforms output by a pre-amplifying circuit by using Labview, statistically analyzing peak values of each waveform, and marking threshold voltages of the particles of 1.0 mu m. The software example of the virtual oscilloscope based on graphical programming in this embodiment is Labview, which is not limited, but may be other software capable of visually displaying various aspects of an application, including hardware configuration, measurement data, and debugging. The particle size channel number according to the particle counter is calibrated through a plurality of particles with preset particle sizes, and the number of the common preset particle sizes is at least 6. In this embodiment, the 6-channel particle counter can be set to adjust 6 threshold voltages by using a mechanical potentiometer to realize different channel counts.
Example two
The intensity of the particle counters is required to be uniform, and the intensity of each point in the whole working area is the same, so that the consistency of the intensity of the optical module of each particle counter is required to be good. As shown in fig. 5, in this embodiment, the standard total value of the optical power of the working area is preset by using an optical power meter in addition to the CCD camera to mark the optical intensity of the laser, the optical power of the working beam is measured, and the optical power of the working area is adjusted to be consistent with the standard total value based on the measurement result. The total power is calculated by adopting an optical power meter, and then the laser power supply is adjusted. When a plurality of particle counters are adopted for counting, an optical power meter is adopted to enable the power of the shaped laser in each optical module to be consistent.
Another main difference between the second embodiment and the first embodiment is that, as shown in fig. 6, the calibration fixture further includes a spot cutting fixture disposed between the attenuation sheet and the photodiode. In the process of calibrating the output voltage of the pre-amplifying circuit, the light spot area of the irradiated photodiode is adjusted through the light spot cutting clamp, and the light intensity of the irradiated photodiode is further adjusted through adjusting the light spot area.
The use of certain conventional english terms or letters for the sake of clarity of description of the invention is intended to be exemplary only and not limiting of the interpretation or particular use, and should not be taken to limit the scope of the invention in terms of its possible chinese translations or specific letters. The foregoing has outlined rather broadly the more detailed description of the invention in order that the detailed description of the structure and operation of the invention may be better understood, and in order that the present invention may be better understood. It should be noted that it will be apparent to those skilled in the art that various improvements and modifications can be made to the present invention without departing from the principles of the invention, and such improvements and modifications fall within the scope of the appended claims.
Claims (6)
1. A particle counting method, characterized by: counting by adopting a particle counter, wherein the particle counter comprises a photoelectric detection part, a main control board, a comparator integrated on the main control board and a potentiometer;
The counting process comprises the following steps:
s1, calibrating a photoelectric detection part of the particle counter; the photodetection member includes: a laser, a photosensitive element and a pre-amplifier circuit;
s2, calibrating threshold voltages corresponding to particles with different particle diameters; the method comprises the steps of collecting waveforms output by a pre-amplifying circuit through particles with a preset particle size in a working area, statistically analyzing peaks of the waveforms, and marking threshold voltages corresponding to the preset particle size;
S3, setting a particle channel of the particle counter according to the particle size, and setting a comparison voltage value adjusted by a potentiometer of the particle channel based on the threshold voltage corresponding to the particles with the particle size;
S4, enabling the particle airflow to be detected to pass through a working area of the particle counter, and comparing the output voltage of the photoelectric detection part with the comparison voltage value by a comparator to distinguish the particle size and count the number;
Before the step S1, shaping the output beam of the laser to obtain a working beam; the step S1 comprises the step of calibrating the laser intensity in advance, wherein the step of calibrating the laser intensity comprises the following steps: calibrating the size of the light spot area of the working beam in the working area and the uniformity of light intensity distribution in the light spot; the specific process comprises the following steps: acquiring spot information of the working beam by using a laser spot collector, wherein the spot information comprises a spot image; whether the size of the light spot meets the requirement or not is evaluated according to the light spot information, and whether the light intensity distribution in the light spot is uniform or not is evaluated; adjusting the distance between the lens and the laser according to the evaluation result; the specific process for calibrating the laser intensity further comprises the following steps: presetting a standard total value of the optical power of the working area, measuring the optical power of the working beam, adjusting the optical power of the working area to be consistent with the standard total value based on a measuring result, setting an optical path turning part in the working area, calibrating the output voltage of the pre-amplifying circuit, and calibrating the output voltage of the pre-amplifying circuit comprises the following steps: an attenuation sheet is additionally arranged between the light path turning component and the photosensitive element to weaken the light intensity of light spots irradiating the photosensitive element; and adjusting the area of the light spot irradiating the photosensitive element through a light spot cutting clamp between the light path turning part and the photosensitive element.
2. A particle counting method according to claim 1, characterized in that: the optical path structure for beam shaping comprises a lens and a diaphragm, and the working beam is a flat-top beam.
3. A particle counting method according to claim 1, characterized in that: in the process of calibrating the output voltage of the pre-amplifying circuit, measuring the output voltage of the pre-amplifying circuit by adopting a universal meter; when a plurality of particle counters are adopted for counting, the pre-amplifying circuit of each particle counter is provided with a potentiometer, and the potentiometer is adjusted so that the output voltage of the pre-amplifying circuit of each particle counter is kept consistent and is equal to the design theoretical value of the output voltage of the photoelectric detection part.
4. A particle counting method according to claim 1, characterized in that: and carrying out one-time statistical analysis on the peak value of the waveform, writing data obtained by the statistical analysis into a memory of the main control board, obtaining the threshold voltage by a processor, and giving out a comparison voltage value adjusted by each channel potentiometer.
5. A particle counting method according to claim 1, characterized in that: a virtual oscilloscope is adopted to statistically analyze the peak value of the waveform; the virtual oscilloscope is based on software programmed graphically, including Labview.
6. A particle counting method according to claim 1, characterized in that: at least 6 predicted particle sizes are included, wherein the predicted particle sizes comprise 0.3 mu m, 0.5 mu m and 1.0 mu m; in step S3, at least 6 particle channels are set, and at least 6 comparison voltage values are adjusted by using a potentiometer.
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| CN202110845099.5A CN113552048B (en) | 2021-07-26 | Particle counting method |
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| CN202110845099.5A CN113552048B (en) | 2021-07-26 | Particle counting method |
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| CN113552048A CN113552048A (en) | 2021-10-26 |
| CN113552048B true CN113552048B (en) | 2024-06-21 |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102012368A (en) * | 2010-10-09 | 2011-04-13 | 中国科学院上海光学精密机械研究所 | System and method for detecting multi-parameter of up-conversion luminescent particles |
| CN102053050A (en) * | 2010-12-07 | 2011-05-11 | 上海理工大学 | Granularity centering measuring method utilizing CCD (charge coupled device) or CMOS (complementary metal-oxide-semiconductor) as photoelectric detector |
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102012368A (en) * | 2010-10-09 | 2011-04-13 | 中国科学院上海光学精密机械研究所 | System and method for detecting multi-parameter of up-conversion luminescent particles |
| CN102053050A (en) * | 2010-12-07 | 2011-05-11 | 上海理工大学 | Granularity centering measuring method utilizing CCD (charge coupled device) or CMOS (complementary metal-oxide-semiconductor) as photoelectric detector |
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