TW200821568A - Pathogen and particle detector system and method - Google Patents

Abstract

The system includes an excitation source for providing a beam of electromagnetic radiation having a source wavelength. A first wavelength selective device is positioned to be impinged by the beam of electromagnetic radiation. The first wavelength selective device is constructed to transmit at least a portion of any radiation having the source wavelength and to reflect radiation of other wavelengths. A medium containing particles is positioned to be impinged by the beam of electromagnetic radiation. At least a portion of the beam of electromagnetic radiation becomes scattered within the medium, the scattered electromagnetic radiation including forward scattered electromagnetic radiation and backward scattered electromagnetic radiation. An optical detector is positioned to receive backward and/or forward scattered electromagnetic radiation.

Description

200821568 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a system and method for detecting aerosol particles or water suspended particles, and more particularly to a method for detecting gas *

Hanging particles or water-suspended particles and systems and methods for classifying the particles by size. The present invention has particular utility in terms of anger and by size classification of allergens and biological warfare agents, and the following description will be made by this use, but the invention may have other uses. [Prior Art] Urban terrorism attacks involving the release of biological warfare agents such as anthrax have become a problem of concern. Weapon anthrax spores are extremely dangerous due to their access to human lungs. For humans, Lv, the lethal inhaled dose of LD5〇 (sufficient to kill 50% of the exposed dose) is about 2,5〇〇 to 50, a spore, see T.V.

The title of Inglesby et al. is "Anthrax of Biological Weapons", / Vol. 281, pp. 1 7 3 5, 1 9 9 . Some other possible weaponic biological agents are Yersinia (plague), Clostridium botulinum (bots botulinum) and francisella tularensis. Given this potential threat, there is an urgent need for an early warning system that can detect such attacks. The laser particles are counted through the same sample, and the scatterer inside the detector is known to be a detection tool for measurement and analysis through the sample. Currently used to detect scatter's which directs laser light to detect detectors or particles from sample light 5 200821568

The problem with counters is that the scatter signal must be extracted from the incident source signal. This means that a weak signal (scattered light from fine particles) must be detected from the background of a lot of noise (the glare from a laser source). This feature is the main reason for the difficulty in detecting the laser particle counter instrument for a long time. The conventional design of the laser particle counter uses a costly and laborious method to reduce glare from a laser source and to measure particle scatter from a large amount of background noise, thereby making the counter extremely fragile and blameless. Currently known laser particle counters are extremely fragile and expensive and are therefore not suitable for this application. Conventional techniques for laser particle counting include a laser Doppler method for measuring particle velocity to estimate particle size, and a transient time method for determining the time required for particles to pass through a sensing region (tr ansi ent time metho) d) and wide-angle multi-sensor design that is only capable of measuring small particles. A biosensor utilizing laser-induced fluorescence of a pulsed ultraviolet (UV) laser is described in T. H. Jeys et al., Proc. IRIS Active Systems, Vol. 1, pp. 235 (1998). This biosensor is capable of detecting the aerosol concentration of 5 particles per liter of air, but its cost is extremely high and fragile. Other particle counter manufacturers are ^1^1:〇116 Instruments, Grants Pass, Oregon, Particle Measurement Systems, Boulder, Colorado, and Terra International, Anaheim, Calif. Based on the design relationship, the construction of these particle counters requires extremely precise optical correction and extremely sensitive sensors and electronics. These products are moving in the direction of laboratory use and are extremely expensive. Therefore, it is not suitable as a detector for field use, and it is not suitable as a design dedicated to biological warfare agent detection. Various detectors have been designed to detect fluid-suspended allergen particles, 6 200821568 2 y Alerts sensitive persons when it is detected that the number of particles in the air sample exceeds a predetermined minimum. These detection systems are described in Hamburger et al., U.S. Patent Nos. 5,646,597, 5,969,622, 5,986,555, 6,008,729, 6' 〇 8 7,947. These detectors all involve directing a beam of light through a sample of the wei wei so that part of the beam will be scattered by any particles in the air: using a beam that transmits scattered light corresponding to a range of angles of the preset allergen size a blocking device and a detector for detecting the transmitted light. If the light measured by the detector exceeds a preset value, a 挲 = is initiated. These detectors provide warning indications based on the presence or absence of allergen particles', but they are not suitable for deployment on site and do not meet the more stringent requirements of pathogen detectors as biological warfare agents. SUMMARY OF THE INVENTION The present invention provides an improved system and method for pathogen and particle detection. More specifically, the present invention develops a novel camp light 4 that utilizes a unique angular distribution pattern of inelastic scattering intensity (i.e., fluorescence from particles). Aged collection method. Theoretically and experimentally, it has been demonstrated that the inelastic scattering of particles has a better intensity angular distribution in the reverse (strongest) and positive (second strong) directions (Reference 1 "from microsphere clusters and tryptophan particles" Inverse Strengthening Twilight" Yong-Le Pan et al., Vol. 41, April 2994, 2〇〇2; Reference 2 "Scattered and Incoherent Raman Spectral Angle and Size Dependent Characteristics of Microspheres j Igor Veselovskii et al., Vol. 41, April, p. 5783, 2002). Briefly, in one embodiment, the system package #~ is used to provide an excitation source having a beam of electromagnetic radiation having a source wavelength. For example, 200821568 A first wavelength selective device such as a spectroscope is placed at a position illuminable by a beam of electromagnetic radiation. The first wavelength selecting means can transmit at least a portion of the radiation having a source wavelength and reflecting radiation of other wavelengths. The medium is placed at a position that can be illuminated by the beam of electromagnetic radiation. At least a portion of the electromagnetic radiation beam is scattered within the medium, the scattered electromagnetic radiation comprising forward scattered electromagnetic light and backscattered electromagnetic light Photodetectors are provided to collect forward and backscattered electromagnetic radiation. The invention may also be considered to provide methods for detecting pathogens and particles. In this regard, one of the embodiments of such methods may broadly summarize the following Step: transmitting an electromagnetic radiation beam; transmitting at least a portion of the electromagnetic radiation beam via the first wavelength selective device; irradiating the particle-containing medium with the portion of the electromagnetic radiation beam, wherein the particle scatters the electromagnetic in the forward and reverse directions Radiation; reflecting at least a portion of the backscattered electromagnetic radiation by the first wavelength selective device; and collecting at least a portion of the forward and backscattered electromagnetic radiation at the first optical detector to determine the forward direction The dimensions of the electromagnetically illuminating particles are scattered in the reverse direction. φ Other systems, methods, features and advantages of the present invention will become apparent to those skilled in the <RTIgt; Other such systems, methods, features, and advantages are within the scope of the present specification and the scope of the present invention, and are subject to the scope of the appended claims. [Embodiment] Fig. 1 shows an optical system for use in a 200821568 fluid suspended particle detector system according to a first exemplary embodiment of the present invention. The first exemplary embodiment of the system has in particular It is used to detect air or water-spreading bioterrorism warfare agents spread by terrorists or others, but can also be used as an urban facility to detect other industrial facilities such as mold or bacteria that may exist in nature or such as food and manufacturing plants. Accidental, inadvertent, natural or deliberate release of other airborne or waterborne particles of detrimental concentration, and use for indoor cleaning.

The term "fluid borne particles" as used herein means particles that are transmitted via air and water. The term "pathogen" as used herein refers to any particle, biological agent or toxin that is transported through air or water. If it is present in sufficient amounts in air or water, it may cause potential harm or even death to humans. Here, "bi ο 1 〇gica 1 agent" is defined as any microorganism, pathogen or infectious substance, toxin, biotoxin, or produced by any such microorganism, pathogen or infectious substance regardless of source or manufacturing method. Any natural, bioengineered or synthetic ingredient. Such biological agents include, for example, biotoxins, bacteria, viruses, rickettsia, spores, fungi, and protozoa, as well as any other pathogen known in the art. "Biotoxin" is a toxic substance produced or derived from living plants, animals or microorganisms, but can also be produced or modified by chemical methods. However, toxins are usually produced naturally by the host organism (i.e., vortexin is produced by seaweed), but genetically engineered and/or synthetically produced toxins have been produced in the laboratory environment. In contrast to microorganisms, toxins have relatively simple biochemical compositions and are not self-reproducing. In many ways, biotoxins can be considered a chemical agent. Such biotoxins are, for example, botulinum toxin and tetanus 9 200821568 toxin, streptococcal endotoxin beta, cyanotoxin, ricin, saxitoxin, Shiga and Shiga toxin, Dendrotoxins, semi-loop caterpillar toxin _b (erabut〇xin_b) and other known toxins. The detection system is designed to detect air or water-borne particles and produce an output that is not indicative of the number of particles in various particle size ranges within the sample, and whether the particles are biological or non-living. Sex particles. • The system may also issue a warning signal or other response when the particles exceed a normal background by a predetermined value and/or are biological organisms or biological agents that may be hazardous. Fig. 1 is an optical system 210 for a water suspension particle detecting system according to a first exemplary embodiment of the present invention. As shown in Fig. 1, the optical system 210 includes an excitation source 2 1 2 for providing an electromagnetic radiation beam 2 1 4 having a source wavelength. In one embodiment, the first wavelength selective device 2丨6 includes a dichroic beamsplitter that is illuminated by the beam of electromagnetic radiation 2丨4. The configuration Φ of the first wavelength selective device 216 can transport at least a portion of any radiation having the wavelength of the source and radiation reflecting other wavelengths. The first wavelength selecting means 2 can reflect a possible splicing wave from the excitation source 2 1 2 (Spuri〇us spectral emissi ns). A portion of the electromagnetic radiation beam 2 1 4 can be reflected by the first wavelength selective device 2丨6 toward a power monitor detector 250. The power monitor detector 250 can be coupled to the excitation source 2 1 2 and can optionally be used as part of a feedback loop that maintains a constant output power of the excitation source 2 1 2 . The electromagnetic radiation beam 214 reflected by the first wavelength selective device 216 toward the power monitoring detector 250 can be concentrated (focused) by the power monitoring lens 256.

The medium 2 18 containing the particles 2 2 0 is placed at a position illuminable by the electromagnetic radiation beam 2 1 4 . At least a portion of the electromagnetic radiation beam 2 1 4 becomes a scattered electromagnetic light shot within the medium 2 18 . The scattered electromagnetic wheel includes forward scattered electromagnetic imaging 222 and backscattered electromagnetic radiation 224. The first optical detector 226 is positioned to receive backscattered electromagnetic radiation 224. The backscattered electromagnetic radiation 224 can be reflected by the first wavelength selective device 216 to the first optical detector 226. A bandpass filter 252 can be utilized between the first wavelength selective device 216 and the optical detector 226 to reduce any backscattered light from the electromagnetic radiation beam 2 1 4 and/or to select a spectrum to be measured. Specific part. A focusing lens 254 can be utilized between the first wavelength selective device 2 16 and the optical detector 226 to focus backscattered electromagnetic radiation 224 toward the optical detector 226. As shown in Fig. 1, the forward scattered electromagnetic radiation 222 can be directed to the first beam blocking lens 260. The first beam blocking lens 260 is designed to reflect non-scattering elements in the electromagnetic radiation beam 2 1 4 to avoid glare on the optical detector. The first beam blocking lens 206 has a material, such as ethylene, attached to the front surface for reflecting the non-scattering elements of the beam of electromagnetic radiation 214. Other considerations for the first beam blocking lens 260 are described in the patent application Serial No. 1 1/1,93,204, which is incorporated herein by reference in its entirety for reference to the same. Element 262 is a low pass filter or a wavelength selective element like in the third exemplary embodiment. The first optical element 262 allows at least a portion of forward scattering 11 200821568 electromagnetic radiation 2 2 2 to pass and reflect a portion of the forward scattered electromagnetic radiation 222. More specifically, the first optical element 262 can reflect the portion of the fluorescent signal of the forward scattered magnetic radiation 222 while allowing the remaining forward scattered electromagnetic radiation 222 to pass. The second beam blocking lens 264 can focus the portion of the forward scattered electromagnetic radiation 222 that faces the particle detector 266. The particle detector 266 can be, for example, a photodiode for measuring the size of the particles 220.

The reflected fluorescent signal portion of the forward scattered electromagnetic radiation 222 can be directed back through the medium 218 and reflected by the first wavelength selective device 216 toward the optical detector 2 26 . A focusing lens 254 can be used between the first wavelength selective device 2 16 and the optical detector 226 to focus the portion of the reflected fluorescent signal that is directed toward the forward scattered electromagnetic radiation 222 of the optical detector 226. Fig. 2 is a block diagram of a particle detecting system according to a first exemplary embodiment of the present invention, which incorporates the optical system 210 of Fig. 1. The optical system 210 includes an excitation source 2 1 2 that directs the beam of electromagnetic radiation 2 1 4 into the first wavelength selective set 2 1 6 . The electromagnetic radiation beam 2 14 enters the medium 2 1 8 through the first wavelength selection device 2 16 and a portion of the electromagnetic wheel 2 1 4 is backscattered to the first optical detector 226, and another A portion of the electromagnetic radiation beam 214 is forward scattered toward the particle detector 266. Two signal dividers 230A, 230B divide the outputs of the first optical detector 226 and particle detector 266 by the output of the power monitor detector 250, respectively. Two amplifiers 232 A ' 23 2B are connected to the output of the signal dividers 230A, 230B. An analog to digital converter 234 is coupled to amplifiers 232A, 232B. A window type comparison circuit (wind〇w 12 200821568 comparator circuit) 23 6 is connected to the analog digital converter 2 34. A control and output display unit 238 is coupled to the output of the window type comparison circuit 236. A low signal detection circuit 240 is coupled to the output of the excitation source 2 1 2 which can provide the power level of the electromagnetic radiation beam 214. The output of the low signal detection circuit 240 is also coupled to the control output display 238. An alarm device 242 is also coupled to the control output display 238. The control output display 238 can be a computer or a variety of software/hardware to control the operation of the particle detector. Fig. 3 is an optical system for a water suspension particle detecting system according to a second exemplary embodiment of the present invention. As shown in Fig. 3, the optical system 3 i 包括 includes an excitation light source 3 1 2 to provide an electromagnetic radiation beam 3 14 having a source wavelength. A first wavelength selective device 316, such as a dichroic beam splitter, is placed at a position that can be illuminated by the electromagnetic radiation beam 314. The first wavelength selective device 316 is configured to transmit at least a portion of any light having a source wavelength and reflecting other wavelengths. The first wavelength selecting means 6 can reflect from the excitation source 312 @ possible axis. A portion of the electromagnetic wheel beam 3 1 4 can be reflected by the first turbidity beam 316 toward the power, the detector 350. The power monitor monitor 35 can be coupled to the excitation source 312: and optionally as part of a feedback loop that maintains a constant output power of the excitation source 312. D -1* The 356 is condensed, and is reflected by the first wavelength selective device 71 toward the electromagnetic radiation beam 3 1 4 of the power monitoring detector 3. The medium containing particles 3 2 0 , is placed at a position that can be illuminated by the electromagnetic radiation beam 3 1 4 . At least part of the electricity ",,

The field beam 314 can become the medium 31S 13

Scattered electromagnetic radiation within 200821568. The scattered electromagnetic radiation includes forward scatter 322 and backscattered electromagnetic radiation 324. The first optical detector is configured to receive backscattered electromagnetic radiation 3 24 . The backscatter 3 4 can be reflected to the optical 326 by the first wavelength selective device 316. A bandpass filter 325 is coupled between the first wavelength selective device 316 and the optical detector 326 to reduce any scattered light from the electromagnetic radiation beam 3 1 4 and/or to select a particular portion of the spectrum to be measured. The poly 3 5 4 can be utilized between the long selection device 3 16 and the optical detector 326 to focus the backscattered electromagnetic radiation toward the optical detector 3 26 : as shown in FIG. 3, the forward scattered electromagnetic radiation 322 can be illuminated to the first beam blocking lens 366. The first beam blocking transmissive system is designed to reflect the non-scattering elements of the electromagnetic radiation beam 3 1 4 to avoid glare on the optical detector. The forward scattered electromagnetic radiation is then directed to an optical element 330, which is a long selection device 316 in the fourth exemplary embodiment. The first optical element 370 permits passage of at least one of the scattered electromagnetic radiation 322 and reflects a portion of the forward magnetic radiation 322. More specifically, the first optical element 370 can scatter the portion of the fluorescent signal of the electromagnetic radiation 322 while allowing it to pass toward the scattered electromagnetic radiation 322. The second beam blocking lens 364 is directed toward the forward scattered electromagnetic radiation 3 2 2 of the particle detector 36. The particle detector 3 66 can be, for example, a photodiode for determining the particle size. The reflected fluorescent signal that can direct the forward scattered electromagnetic radiation 3 2 2 is directed toward the second optical detector 376. The first optical element 370 and the electromagnetic radiation 266 can be guided by the back to the first wave lens it 3 24° while the mirror 3 60 can avoid the second wave partial positive scattering. The positive reflection of the positive reflection can pass through the portion of the portion 320. The second optics 14 200821568 A second device f-pass filter 372 can be used between the detectors 376 to reduce any radiation from the electromagnetic radiation beam 3 1 4 The light &amp; u April is scattered light and / or used to select a specific part of the spectrum to be measured. A focus-transmission-by-mirror 374 can be used between the first-soil beta hang-up element 3 70 and the second optical detector 3 76 to focus the forward-scattering electromagnetic Μ ^ ^ ^ toward the second optical detector 376 a ^ &amp; 322 reflects the fluorescent signal portion. The second optical debt detector 376 can be 俐 lime stop + at π - mum 4 such as a photomultiplier tube (PMT) optical detector.

Fig. 4 is a block diagram of a particle detecting system 301 according to a second exemplary embodiment of the present invention, which incorporates the optical system 3 of Fig. 3. The optical system 310 includes an excitation source 3 1 2 that directs the beam of electromagnetic radiation 3丨4 into the first wavelength selective device 3 16 . The electromagnetic radiation beam 3 4 enters the medium 318 through the first wavelength selection device 316 and a portion of the electromagnetic radiation beam 3 14 is backscattered to the first optical detector 3 26 and another portion The electromagnetic radiation beam 314 is forward scatter toward the particle detector 366. The two L 5 tigers are divided into 3 30 A, 3 3 0 B, and 3 3 0 C to divide the outputs of the first optical detector 326, the particle detector 366, and the second optical detector 3 76 by power monitoring, respectively. The output of the detector 3 50. Three amplifiers 332A, 332B, 332C are connected to the rotation of the signal dividers 330A, 330B, 330C. An analog to digital converter 334 is coupled to amplifiers 332A, 332B, 3 3 2C. A window type comparison circuit 336 is coupled to the analog digital converter 334. A control output display 337 is coupled to the output of the window type comparison circuit 336. A low signal detection circuit 340 is coupled to the output terminal of the excitation source 3 12 which provides the power intensity of the beam of electromagnetic radiation 3 1 4 . The output of the low signal detection circuit 340 is also coupled to the control output display 338. 15 200821568 An alarm device 342 is also coupled to the control output display 3 3 8 . The control output display 3 3 8 can be a computer or a custom software/hardware for controlling the operation of the particle detector.

The system design is based on the Mee scattering principle of particle size equivalent to the wavelength of light. In the Mie scattering state, the angular distribution and intensity of the scattered light are closely related to the size and shape of the particles. Scattering is characterized by the following characteristics: 1) the scattered light is focused in the forward and reverse directions; 2) the angular distribution of the scattered light intensity is extremely sensitive to the size of the scattering particles; and 3) the scattering cross section of the particle It is proportional to the size of the particles in a monotonous but complex way. Using visible light, such as a visible laser dipole output beam with a wavelength of 6 · 67 μm, the Mie scattering method is suitable for detecting and characterizing suspended particles in the micron range. Figure 5 is a graph showing the relationship between the Mie scattering cross section and the particle radius. According to a second exemplary embodiment of the present invention, the optical system 310 of the detection system 310 uses the principle that the scattering angle is proportional to the particle size, and is blocked by the first beam placed on the light path through the sample. The lens 306 removes scattered light outside the preset range. Since the scattering cross section of the particle is proportional to the particle size in a monotonous but complex manner as depicted and depicted in Figure 5, the particle detector 366 is designed to resolve the measured pulse height by Differences are used to detect the distribution of particle sizes within the sample. Therefore, the height of the electrical pulse output from the particle detector 366 depends on the size of the particles. As shown in FIG. 4, the output of the particle detector 366 is connected to an input of the second signal divider 3 3 0B, and the power monitor detector 350 (which is equivalent to the excitation source 31). The output of 2) is connected to the other input of the second signal division 16 200821568 33 0B, and from the second ^ ^ ^ ^ 除 Β Β 330 Β 値 値 値. Figure 6 is the analogy of digital conversion, 334, imprisonment, ^ + brother, an exemplary embodiment, 佚 佚 〇 J * 3 4, self-form than the parent circuit Βξ λλο, ^ ^ 36 and control output display 33 The pulse height measurement circuit composed of 8 ^ ^ . Ghost diagram ' at the same time Figure 7 is a more detailed description of the analog digital converter 334 crying recognition 1 50 thumbnail. The output of the particle detection 366 can be a pulse signal t π # I / 。 6 shows a signal 6 in a 类 column analog pulse signal. ' each pulse represents a medium in the river

The scattering of the particles is $' and the height of the pulse is proportional to the size of the particles. In order to remove the DC background, each input pulse from the particle detector 3 ".nnng pluse" passes through a high pass filter Q and then passes through a buffer 64 to the peak detector 65' which will measure the input. The height of the pulse: The output of the peak detector 65 will be - a series of pulse count signals with pulse height data. The embodiment of the digital converter and the peak detection circuit is described in detail in Figure 7, Figure 7a. The pulse output values of the points in the circuit are shown. The "ΡΕΑκ 〇υτ" output signal in the figure f 7 A is sent to the window type comparison circuit 336 for classification. The other pulses shown in the figure are time and enable signals to inform the window type comparison circuit 336 to retrieve and store the data. The window type comparison circuit 336 has a series of window type comparators 66 (labeled as 1 to 10 in the embodiment of FIG. 6) for detecting within a preset voltage range (window voltage, wind 〇 wv 〇 itage) Pulse. Each window comparator 66 transmits a signal to its associated digital counter 68 ° when the input pulse height falls within its window voltage range (eg, comparator #5 is 5 to 7.5 volts). The output of counter 68 (block) is connected to 17 200821568 a display panel 70 which will display the number of particles of each particle size. Therefore, the control output display 338 may include a bar graph illuminated by an array of light emitting diodes (LEDs) that are sequentially illuminated according to input values from respective counters of respective particle sizes. To produce a histogram of the particle size distribution. The different particle sizes in the bar graph can have different colors. The output value can also be connected to a stylized computer to display a histogram of the particle size distribution on its screen.

The window type comparison circuit 363 has a plurality of window type comparators 6 6 and a digital counter unit 6 8 to calculate pulses corresponding to the particle diameter within the target range. In Figure 6, 10 such blocks are shown. However, 14 pieces can be provided at intervals of 0.5 μm between the particle diameters of 1 to 7 μm. Fewer or more comparators and counters may be provided if a smaller or larger particle size range is desired, such as a narrower range of pathogen sizes between 1 and 5 microns. Fig. 8 is a view showing an embodiment of a histogram of the particle size distribution. Although it shows a distribution range from 1 to 19 microns, it should be understood that the programmable control output display 3 3 8 can display a narrower range of 1 to 7 microns or a particle size distribution histogram of any desired range. The output of the control output display 338 can also be coupled to a visual and/or audible alarm device 342, such as a warning light and buzzer at the front end of the housing. Any suitable software can be used to generate the output display histogram, such as the Lab View software supplied by National Instruments, Austin, Texas. The software can also be used to generate an output of the activation alarm device 42 if the counted amount within the particle size range of a pathogen or biological agent exceeds a predetermined concentration in the normal environment. This will help reduce or even eliminate the risk of false positives. The computer's input 18 200821568 can also be used to trigger a more sophisticated biologic detection device, such as an anthrax detector using PCR technology. This combined detection method will be cost effective and further reduce the risk of false positives. In an improved configuration of the invention, as is known for processing such a

The processing of the substance, and it is known that there is a unique pattern of identification size distribution for the instrument used in the treatment procedure, so that the histogram of the size distribution of the suspended particles can be compared with the profile of known weaponized biological agents. Comparison. Thus, the detection system of the present invention provides forensic information from manufacturers of biologics from potentially available sources. As noted above, biological agents most likely to be used in terrorist attacks range in particle size from 1 to 7 microns. Table 1 below shows the characteristics of the bioterrorist agent types recorded by the Centers for Disease Control: Table 1. Types of bioterrorist agents Biological warfare agent size characteristics Anthrax rods: width 1. 〇-1.2 μm, length 3.0-5.0 μm (spore 1.0X1 · 5 microns) Yersinia (plague) 隋 round: 1.0-2.0 micron botulinum botulinum rod shape: 0.8-1.3 microns wide, 4·4-8.6 micron Frans Rabbit heat bacteria rod shape: 0.2 micrometers wide, 0.7 micrometers long. The fluid suspension particles naturally present in the ambient air of about 1 to 7 micrometers are extremely small and have a constant concentration. The peaks of the smoke intrusion particle size in the metropolitan area and the sudden occurrence of local dust sources are 微米.3 μm and 5 μm, respectively. During the flower season, pollen and other allergens may also be present in the air, and the size of the allergen particles is between about 5 and 50 microns. Therefore, only a few of these natural suspended particles fall within the particle size range of biochemical warfare agents.

Inside (1 to 7 microns). Further, although the mold has a particle diameter of about 1 to 5 μm, the number of mold particles in any specific region does not usually change abruptly. Therefore, the detection system 301 according to the fourth exemplary embodiment is designed to detect the particle size within the specific size range and generate an output representing the particle size detection range at intervals of 微米.5 μm. . The sudden and regional increase in the number of suspended particles with any particle size between 1 and 7 microns is most likely to deliberately release aggressive biological warfare agents or pathogens. The system can be configured to detect and store the natural background concentration of the particles within the desired particle size range and then use the background concentration as the comparative concentration of the subsequent output histogram to initiate the detection of a sudden increase in particle size. Alarm. The particle size histogram in Figure 8 shows a possible dangerous state. In the figure, the number of particles detected in the 1 to 7 micron particle size has far exceeded the normal value. Although the particle detection system described above cannot distinguish specific particles, since the suspended particles in this target range are usually relatively rare in a normal urban air environment, they can be used as a sensitive and warning for suspended biological warfare agents. A cost-effective approach. Particles falling within this range may invade the human lungs and cause possible injury or even death of the inhaler. The alarm device 3 42 can immediately dissipate warnings to nearby people to reduce the risk of exposure to the agent. The detection system 310 can also be used to detect the hazard of hazardous dust in the factory. For example, the harmful asbestos fibers are about 5 microns in size, which typically have a length of about 5 microns or more and a diameter of about 1-2 microns. Damage can also be caused if whisk dust between 1 and 5 microns is inhaled into the lungs. The detection system 310 can be placed in a building containing asbestos or as a construction worker at 20 200821568

When working in such buildings, a warning signal is generated when an abnormal peak in the range of 1 to 5 microns is detected, indicating a dangerous amount of asbestos fibers in the air. Similarly, the detection system 310 can be placed in the vicinity of a worker who manufactures a defective part to generate a warning signal when the number of particles between 1 and 5 microns suddenly increases, indicating that the dust may have reached a dangerous concentration. The detection system 310 can not distinguish the asbestos or dust in the same particle size range under normal conditions, but when working in the asbestos or sputum environment, if the particles within the particle size range suddenly increase, it should be possible to listen. An indication of a dangerous state immediately evacuates the area for further testing. Similarly, the detection system 301 can also be used in aseptic manufacturing plants, such as food or pharmaceutical manufacturing plants, to monitor microbial spills in a continuous manner, and to take emergency remedial measures in the first place. Similarly, the detection system 301 has been used as a continuous monitoring system to alert the plant manager of historical data and trend information about microbiological detection based on the requirements of the clean room. In the above detection system 310, a two-stage detection and discrimination process is used, and the system having the optical system 310 first removes scattered light that falls outside the predetermined angular range including the target particle size range. Next, the detected output pulse is identified based on the pulse height, the number of pulses at each height is calculated and converted to a particle size of, for example, 0.2 microns, and the result is displayed as a histogram and generated at appropriate intervals. A new histogram to illustrate the change in particle distribution. However, in addition to the particle size distribution histogram display, the optical portion of the detection system 310 can be configured to direct only portions of the scattered light signal corresponding to the 1 to 7 micron particle size range to detection. The first portion of the detection system 3 0 1 and the detection system 3 0 1 are configured to detect the system 3 0 1 of 21

200821568 A warning signal will be sent if the output exceeds a preset threshold. This will provide an inaccurate output and will not be able to determine the identification within the size range of the detection, but if there is an equivalent amount of particles known to be suspended pathogens, allergens or other harmful particles such as ochre, the number of particles is unusual. When added, a relatively accurate alert can still be generated. The optical 310 of Figure 3 only needs to be modified to provide a larger central blocking zone to block scattered light of particles of about 7 microns, and the output circuit is modified in the particle detector 3 6 6 The output provides a threshold discriminator to provide an alarm from the discriminator to activate an alarm if the measured signal is above the selected threshold. The pathogen detector of the present invention can be used in a variety of applications. For example, the body detector can be implemented as a battery powered portable, detector for field personnel. In this case, the outer casing can accommodate the optical device and the circuit for calculating the particles by the circumference, and the display having the count of the particles for displaying the respective particle diameters, such as an LED display. It may also include a device to transmit wireless signals to a base station. It may also include a sounder and a warning light to indicate that the laser power is insufficient. Stand-alone, desktop instruments in buildings such as public buildings are also available. This stand-alone upper model is similar to the one used in the field, but it is powered by an AC/DC to a standard power outlet on the wall. In the latter case, the detector provides protection against letters or documents contaminated with biological warfare agents. The detector can also be used as a part of a multi-purpose building security system, which is placed in a different room and connected to a central monitoring computer or for larger particle size dust or a large number of sturdy systems. In front of the transmission of the alarm, the table changer 'the package is a control unit 22 200821568 multiple detectors. The console can be programmed to monitor the number of particles in each room, as well as to analyze the source of abnormal increase in particle size for any pathogen, and to predict the possible mode of dissemination of pathogen particles within the building. The detector can be connected using physical lines or have a radio transmitter to transmit data to the central console to analyze the source of any increase in biological warfare agent particles and the possible diffusion patterns of any biological warfare agent.

The fluid suspended particle detector disclosed herein can also be used to monitor a clean room to prevent possible contamination and/or material loss. When the detection system 300 is used to a larger extent, the alarm device 3 42 is activated only when the following two conditions are met: (1) When it is detected in the preset particle size range (about 1 to about 7 nm) When the number of aerosol particles in the chamber suddenly increases; and (2) when a biological organism, a biological warfare agent or an organic substance is detected by laser-induced fluorescence as described below. The particle size sensor itself has the disadvantage of environmental particle false alarms. If the pathogen detection system 310 is a bioorganism or biological warfare agent detector that incorporates an ultraviolet-induced fluorescence sensor to distinguish the particle size of the biological or non-bio-particles, further Reduce these false positives. The detection system 301 of the present invention includes a first optical detector 326 and a second optical detector having a laser-induced fluorescence sensor to detect metabolites of biological organisms or biological agents such as biological warfare agents. 3 76. More specifically, the optical system 310 includes an excitation source 312 that is operable at a wavelength of from about 270 to about 410 nm, preferably from about 3 50 to about 410 nm. When the biologic contains three major metabolites: tryptophan, which typically emits fluorescence at about 270 nm (in the range of about 220 to about 300 nm); the nicotinamide 23, 200821568 嗓吟 dinuclear (NADH), It typically emits fluorescence at about 34 〇 nanometers (ranging from about 3 〇〇 to about 400 nm); and rib flavin, which is usually at about 400 nm (from about 320 to about 42) In the case of fluorescing under the 〇 nanometer range) 'Select about 270 to about 4 丨〇 nanometer wavelength. However, the excitation source 3 1 2 preferably has a wavelength of from about 3 5 〇 to about 4 1 〇 nanometer. This wavelength ensures that two of the three major metabolites in the biologics, the biological agents NADH and riboflavin, are excited, but do not excite other interfering substances such as diesel-oil engine exhaust and other inert particles such as dust or talcum powder. . Therefore, in the fourth embodiment, the selection wavelength range of the excitation light source 3丨2 is capable of retaining the ability to excite the fluorescence of NADH and riboflavin (the above-described ability to stimulate the tryptophan acid) while not exciting other interference such as diesel exhaust gas. Things. This step can reduce the false alarm caused by diesel exhaust gas (which can be excited by a short 11¥ wavelength such as 266 nm light. Figure 9 shows the fluorescence spectrum of the above four metabolites. Spectral analysis, special 5 Spectral analysis of different excitation wavelengths can detect the composition of microorganisms' and can be used to detect and classify microorganisms

The outputs of the optical detectors 326, 768 are connected to the dividers 3 30A, 33 0C, respectively, and are further connected to the control display device 3 3 via the amplifiers 3 3 0A, 3 3 0C and the analog digit converter 334. </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> <RTIgt; The above-described embodiments of the present invention can be modified in many different ways, but without departing from the spirit and principles of the present invention. All such improvements and variations are within the scope of the disclosure and the scope of the invention, and are protected by the scope of the following claims. [Simple description of the map]

A wide variety of aspects of the invention will be apparent from the following drawings. The components in the figures are not necessarily to scale, but rather to clearly illustrate the principles of the invention. In addition, the same component symbols are used to denote corresponding components in the drawings. Fig. 1 is an optical system for a fluid-suspended particle detecting system according to a third exemplary embodiment of the present invention. Figure 2 is a block diagram of a particle detection system incorporating the optical system of Figure 1 in accordance with a third embodiment of the present invention. Figure 3 is an optical system for a fluid suspended particle detection system 701 in accordance with a fourth exemplary embodiment of the present invention. Fig. 4 is a block diagram of a particle detecting system of the optical system according to the third embodiment of the present invention and incorporated in Fig. 3. Figure 5 is a plot of the Mie scattering cross section versus particle radius. Figure 6 is a block diagram of a pulse height measuring circuit constructed by an analog-to-digital converter, a window comparator circuit, and a control output display in accordance with a fourth exemplary embodiment of the present invention. Fig. 7 is a schematic diagram of an analog digital converter according to a fourth exemplary embodiment of the present invention. Figure 7A is a graphical illustration of the output of an analog-to-digital converter at various points in accordance with a fourth exemplary embodiment of the present invention. 25 200821568 Figure 8 is an illustration of a histogram of particle size distribution. Figure 9 shows the fluorescence luminescence spectra of the four metabolites.

[Main component symbol description] 14 Detector 62 High-pass filter 65 Peak detector 68 Digital counter 210 Optical system 2 1 4 Electromagnetic radiation beam 21 δ Medium 222 Forward scatter electromagnetic radiation 226 First optical detector 2 3 0 Β Signal division 23 Β amplifier 2 3 6 window type comparison circuit 240 low signal detection circuit 252 band pass filter 2 5 6 power monitoring lens 262 first optical element 266 particle detector 3 10 optical system 3 1 4 electromagnetic radiation beam 60 Signal 64 Buffer 6 6 Window Comparator 7 0 Display Board 2 12 Excitation Source 216 First Wave Selector 2 2 0 224 Backscattered Electromagnetic Radiation 23 0Α Signal Divider 232 Α Amplifier 234 Analog Digital Converter 2 3 8 Control output display 2 50 power monitoring detector 2 5 4 focusing lens 260 first beam blocking lens 2 6 4 , second beam blocking lens 3 0 1 particle detecting system 3 12 excitation light source 3 1 6 first wavelength Selection device 318 medium 320 particles 3 2 2 forward scattered electromagnetic radiation 3 2 4 backscattered electromagnetic radiation 26 200821568 326 first optical detector 3 30A signal divider 3 3 0B signal Xu 3 3 C 0. Divider 3 32A Amplifier 332B Amplifier 3 3 2 C Amplifier 3 3 4 Analog Digital Converter 3 3 6 Window Type Comparison Circuit 3 3 8 Control Output Display 3 40 Low Signal Detection Circuit 342 Alarm Device 3 5 0 Power Monitoring Detector 3 5 2 bandpass filter* 0 356 power monitoring lens 3 60 first beam blocking lens 3 64 second beam blocking lens 3 6 particle detector 370 first optical element 3 7 2 second band pass filter Lighter 3 74 Focusing Lens 3 7 6 Second Optical Detector • 27

Claims (1)

200821568 X. Patent Application Range: 1. A particle detection system comprising: a housing having the same groove area; a light source positioned on one side of the sample slot for transmitting a beam through the sample, Thus, a portion of the beam is scattered by small particles in the sample region at various angles, and the unscattered portion of the beam is not scattered; a beam blocking device is located on the opposite side of the sample slot, At least a portion of the unscattered portion of the beam and the perimeter of the limiting particle; a first detector disposed in the rear of the beam blocking device for detecting a portion of the forward scattered light and generating a number of forward scattering particles falling within a predetermined particle size range; a second detector placed on the light source side of the air sample slot, measuring a portion of the backscattered light, and generating An output comprising the information of the number of backscattered particles within a predetermined particle size range of the optical path. The system of claim 1, wherein the backscattered light system in the anti-media is further Wavelength selection Reflection to be received by the detector. Focusing light, various large, used to resist the measurement of the light path, the information used for the detection of the fall in the device. 200821568 3 - The system of claim 1, further comprising a policeman for providing a normal value when the number of particles in the predetermined particle size range exceeds a preset particle size range of about 10 micrometers The alarm signal is the system of claim 1, wherein the light source is outside. Φ 5. The system of claim 1, wherein the light source is a light emitting diode (LED). 6. The system of claim 5, further comprising a portion disposed between the light source and the first wavelength selective device. 7. The system of claim 1, further comprising a processor coupled to the output of a pulse height discriminator for processing the particle size distribution according to the height of each pulse wave at a specified time, and suspending A histogram of the particle size distribution and a graph on an output device. 8. The system of claim 1, further comprising: a first lens placed at a position illuminated by the beam; a first filter placed at a position illuminated by the beam; a second lens, Provided to transmit at least a portion of the positive reporter, 1 to 7 〇 emit violet including a mirror, to filter the columnar scattering 29 200821568 light; a first optical component placed at least a portion of the position at which the forward scattered light is illuminated, wherein the first optical element transmits only a specific band of the portion of forward scattered light; and a second optical detector is configured to receive and transmit The portion of the first optical element that is imaged forward scatters light, such that the second optical detector determines the size of the particles within the medium. 9. The system of claim 8 wherein the first lens further comprises a collimating mirror. The system of claim 8, further comprising a detecting lens configured to receive and transmit radiation reflected by the first wavelength selective device, and a detector disposed for use Receiving radiation from the detection lens, wherein the detector is in communication with the light source. The system of claim 8, further comprising a third optical detector, wherein the third optical component is a second wavelength selective device for reflecting at least a portion of the forward scattering The light is directed toward the third optical detector. 1 2. The system of claim 8 wherein the first optical component is a filter disposed to transmit only a portion of the forward scattered light of a 30 200821568 specific band, wherein the other waves The strip is reflected by the filter and faces the first optical detector along the optical path. The system of claim 8, wherein the source wavelength is between about 35 and 400 nanometers and the first filter transmits light of less than about 400 nanometers. The system of claim 8, further comprising at least one beam blocking lens optically disposed between the medium and the second optical detector, wherein the optical blocking lens The scattered light is transmitted and the non-scattered light is reflected or absorbed. The system of claim 1, further comprising at least one filter optically disposed between the medium and the first optical detector, wherein the filter is transmitted from the Backscattered light from the medium and reflected electromagnetic light from the source. 1 6. The system of claim 5, further comprising a plurality of optical lenses for shaping light from the LED to be near collimated light. The system of claim 1, wherein the light source comprises a plurality of optical lenses for shaping the light and/or removing noise from the light beam. The system of claim 1, wherein the sample well comprises an air sample tank. The system of claim 1, wherein the sample well comprises a water sample tank. The system of claim 1, wherein the first wavelength selective device comprises a dichroic beam splitter. The system of claim 1, wherein the first wavelength device comprises a dichroic beam splitter. 22. The system of claim 12, wherein the first optical component is a low pass filter. A method for detecting a pathogen and a particle, the method comprising the steps of: emitting a light beam; transmitting at least a portion of the light beam through a first wavelength selective device; and irradiating the particle beam with the partial light beam a medium, wherein the particles scatter the light in forward and reverse directions; and the backscattered light and the backscattered light are measured and measured. The method of claim 23, further comprising: reflecting at least a portion of the backscattered light with the first wavelength selective device; receiving at least one portion of the first optical detector The backscattered light is thus determined to measure the size of the particles that backscatter the light. The method of claim 23, further comprising: transmitting at least a portion of the forward scattered light through a second lens; Transmitting only a particular band of the portion of forward scattered light through a first optical element; and receiving, by a second optical debt detector, the portion of forward scattered light transmitted through the first optical element such that A second optical detector measures the size of the particles that forwardly scatter the light. 26. The method of claim 23, further comprising: reflecting, by the first optical component, a portion of the forward scattered light toward a third optical detector, wherein the first optical component is Second wavelength selection device. The method of claim 23, further comprising: focusing, by a third lens, the portion of the first optical element that is transmitted through the first optical element toward the second optical detector for forward scattering Light, wherein the third lens reflects non-scattered light. The method of claim 23, further comprising: 33 200821568 focusing a fourth lens to be backscattered by the first wavelength selective device toward the portion of the first optical detector Light. The method of claim 23, further comprising: filtering, by a filter, the backscattered portion of the first optical detector that is reflected by the first wavelength selective device Light. 34