JP2003038163A - Microorganism detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microorganism detector for detecting particulate microorganisms including bacteria, virus and pollen suspending in the atmosphere, enabling the number of them to be measured accurately in real time. SOLUTION: This microorganism detector works as follows: the air is introduced by a suction pump 1 and injected into a nozzle 2, and irradiated with infrared rays and ultraviolet rays from a semiconductor laser 3a and an ultraviolet LED 3b respectively; and the rays emitted from the semiconductor laser 3a and scattered by particulate microorganisms in the air are received via an infrared transmission filter 6a by a light-receiving element 7a, while the rays or fluorescence emitted from the ultraviolet LED 3b and reflected by the particulate microorganisms in the air are received via a band pass filter 6b by another light-receiving element 7b; based on the respective outputs of these light-receiving elements 7a and 7b, the number of the particulate microorganisms in the air is counted by the aid of an arithmetic circuit 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microorganism detecting device for instantaneously (real-time) detecting particulate microorganisms such as bacteria, viruses and pollen floating in the atmosphere.

[0002]

2. Description of the Related Art In recent years, it has become necessary in food factories and the like to simply and quickly measure microorganisms present in the atmosphere in order to control the manufacturing process. In addition, pollen information is being demanded in real time even outdoors.

At present, such microorganisms in the atmosphere are mainly detected by a method based on culture. In addition, as a means for measuring the amount of pollen and the like, it has been practiced to collect pollen and the like on a slide glass or an adhesive tape and visually measure it with a microscope.

[0004]

By the way, in the conventional detection of microorganisms as described above, since considerable dust and sand are present in the air in addition to microorganisms, even if a particle counter is applied, other Particles could not be measured and only specific particles could not be measured.

Further, when only reflected light or fluorescence is detected using only visible light or ultraviolet light, the amount of detected light received changes depending on the component and content of the fluorescent substance in the particles,
The size of the particles could not be discriminated.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a microorganism detecting apparatus capable of accurately measuring the number of microorganisms in the atmosphere in real time.

[0007]

A microorganism detecting device according to the present invention is a device for detecting microorganisms in the atmosphere, and is an introducing means for sucking and introducing the atmosphere, and irradiating the introduced atmosphere with infrared rays. A light source, a light receiving element that receives light scattered by microorganisms in the atmosphere from the light source through an infrared transmission filter, a light source that irradiates the introduced atmosphere with visible light or ultraviolet light, and from this light source And a light receiving element for receiving light or fluorescence reflected by the microorganisms in the atmosphere through a bandpass filter, and an arithmetic means for calculating the number of the microorganisms in the atmosphere from the output of each light receiving element. is there.

Further, a detecting means for detecting the particle size of the microorganism based on the output of the light receiving element and a detecting means for detecting whether or not the microorganism are present are further provided, and the type of the microorganism is discriminated based on the output of the light receiving element. It is provided with a discriminating means.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing a basic structure of a microorganism detecting apparatus according to the present invention, which is configured as a microorganism counter for detecting microorganisms floating in the atmosphere and measuring the number thereof.

In the figure, 1 is an atmosphere (air) containing microbial particles such as bacteria, viruses and pollen which are samples to be detected.
Atmospheric pressure is introduced by a suction pump (introducing means) at a constant flow rate into the nozzle body 2 from the air intake port in the upper part of the device body as shown by an arrow in the figure, and the atmosphere is injected into the device body by the nozzle 2. Emitted from the bottom.

Reference numeral 3a denotes a semiconductor laser (light source) for irradiating infrared rays to the atmosphere introduced and jetted into the apparatus main body, 4
Reference symbol a denotes a collimator lens arranged in front of the semiconductor laser 3a, reference symbol 5a denotes a cylindrical lens for converting infrared rays into a sheet shape at a detection portion near the injection port of the nozzle 2, and 6
Reference symbol a denotes an infrared transmission filter that transmits infrared rays, and reference symbol 7a denotes a light receiving element such as a photodiode that receives the infrared rays scattered by the microbial particles.

Reference numeral 3b designates an ultraviolet LED (light source) for radiating ultraviolet rays to the atmosphere introduced and jetted into the apparatus body 4b.
Is a collimator lens arranged in front of the ultraviolet LED 3b, 5b is a cylindrical lens that makes ultraviolet rays into a sheet shape at the detection portion near the ejection port of the nozzle 2, and 6b is a visible ray such as yellow that is fluorescent by microbial particles with ultraviolet rays. A bandpass filter for transmitting light rays, and 7b is a light receiving element such as a photodiode for receiving the light.

FIG. 2 is a block diagram showing the configuration of the detection circuit of this embodiment, showing the configuration of the signal processing system after converting the optical signal into an electrical signal by the light receiving elements 7a and 7b.

In FIG. 2, reference numeral 8a is a detection means for detecting (determining) the particle diameter of particles such as microbial particles and dust in the atmosphere introduced into the apparatus main body based on the output of the light receiving element 7a, and 8b.
Detecting means for detecting (determining) whether the particles in the atmosphere fluorescent in the main body based on the output of the light receiving element 7b are microbial particles or dust particles, and 9 is the microbial particles in the atmosphere from the outputs of the detecting means 8a and 8b. The arithmetic circuit (arithmetic means) for arithmetically operating the number of the above constitutes the discrimination means for discriminating the type of the microbial particles.

In the microorganism detecting apparatus constructed as described above, the light emitted from the semiconductor laser 3a which is one of the light sources and scattered by the microorganism particles in the atmosphere is received by the light receiving element 7a through the infrared transmission filter 6a, The light emitted from the ultraviolet LED 3b, which is the other light source, and reflected by the microbial particles in the atmosphere is received by the light receiving element 7b through the bandpass filter 6b. Then, from the outputs of these light receiving elements 7a and 7b, the arithmetic circuit 9 counts the number of microorganisms in the atmosphere. Thereby, the number of microorganisms in the atmosphere can be accurately measured in real time.

Here, in this embodiment, as shown in FIG.
If Y and Z are taken, the two light sources are 1 with respect to the Z axis.
It is shifted 5 degrees. This is because the light from the ultraviolet LED 3b is received diagonally by a photodiode or the like and the ultraviolet LED
This is to make the emission intensity of 3b constant.

Further, the outputs of the detection means 8a and 8b have a time difference because the optical axes are different, and this time difference is obtained by calculation from the inner diameter of the nozzle 2, the suction flow rate, and the optical axis angle. When both outputs are detected within a fixed time, the arithmetic circuit 9 determines that the particles are microbial particles.

FIG. 3 is a diagram showing the relationship between the wavelength of light reflected by pollen and the reflectance. In FIG. 3, (a) shows the case of cypress and (b) shows the case of cedar. Further, FIG. 4 is a diagram showing the relationship between the relative intensity of fluorescence due to pollen and the wavelength.
Shows the case of Japanese cypress and (b) shows the case of Japanese cedar.

The grain size of cedar pollen and cypress pollen is about 30 μm.
Although the output of the light receiving element 7a is almost the same, there is no difference between the cedar and the cypress pollen in the fluorescence characteristics at the excitation wavelength of 370 nm in FIG. ) And infrared light scattered by two wavelengths can be distinguished.

That is, as a method, there are a method of detecting fluorescence due to excitation in ultraviolet and visible light (also using infrared light) and a method of discriminating by a difference in scattering characteristics between two wavelengths of visible light and infrared light. Includes types.

The above-mentioned difference can also be identified and detected by the arithmetic circuit 9, and the type of microorganism can be identified. Since ragweed pollen has a particle size of about 18 μm, which is different from cedar and cypress pollen, this can also be identified by the difference in particle size.

In the above embodiment, the ultraviolet LE
Alternatively, D3b may be a light source that emits visible light. Further, the configuration of the device is not limited to the configuration of the embodiment.

[0024]

As described above, according to the present invention,
There is an effect that the number of microorganisms in the atmosphere can be accurately measured in real time.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a basic configuration of a microorganism detecting device according to the present invention.

FIG. 2 is a block diagram showing a configuration of a detection circuit according to an embodiment.

FIG. 3 is a diagram showing the relationship between the wavelength of light reflected by pollen and the reflectance.

FIG. 4 is a diagram showing the relationship between the relative intensity of reflected light from pollen and wavelength.

[Explanation of symbols]

1 Suction pump (introduction means) 2 nozzles 3a Semiconductor laser (light source) 3b UV LED (light source) 4a Collimating lens 4b collimating lens 5a Cylindrical lens 5b Cylindrical lens 6a Infrared transmission filter 6b bandpass filter 7a Light receiving element 7b Light receiving element 8a Detection means 8b detection means 9 Arithmetic circuit (arithmetic means, discrimination means)

Continued front page    F term (reference) 2F065 AA26 BB05 BB15 CC16 DD04                       FF23 FF41 GG06 GG22 GG23                       HH03 JJ01 JJ18 LL22 QQ25                       QQ51                 2G043 AA01 BA17 CA06 DA05 EA01                       EA14 FA06 GA01 GA07 GB01                       HA01 JA03 KA01 KA03 KA09                       LA01                 2G059 AA05 BB02 BB06 BB09 CC19                       EE02 GG01 HH01 JJ02 JJ11                       KK01 MM01                 4B029 AA07 BB01 CC01 FA03 FA06                       FA10

Claims (3)

[Claims] 1. An apparatus for detecting microorganisms in the atmosphere, comprising an introducing means for sucking and introducing the atmosphere, a light source for irradiating the introduced atmosphere with an infrared ray, and a light source for emitting infrared rays from the light source. A light-receiving element that receives light scattered by microorganisms through an infrared transmission filter, a light source that irradiates the introduced atmosphere with visible light or ultraviolet light, and light or fluorescence that is reflected by microorganisms in the atmosphere from this light source. A microorganism detecting apparatus comprising: a light receiving element that receives light through a band pass filter; and a calculation unit that calculates the number of microorganisms in the atmosphere from the output of each light receiving element. 2. The microorganism detecting device according to claim 1, further comprising a detecting means for detecting the particle size of the microorganism based on the output of the light receiving element and a detecting means for detecting whether or not the microorganism is a microorganism. 3. The microorganism detecting apparatus according to claim 2, further comprising a discrimination means for discriminating the type of microorganism based on the output of the light receiving element.