KR20180113341A - Apparatus for sensing particle - Google Patents

Abstract

The present invention provides an apparatus for sensing particles which can accurately measure a particle concentration. According to embodiments of the present invention, the apparatus for sensing particles comprises: a light emitting unit to emit light; a flow passage unit arranged in a first direction crossing an optical axis of the light emitting unit underneath the light emitting unit, in which air including particles flows; a light receiving unit which is arranged on the optical axis underneath the flow passage unit, and receives scattered light for each particle flowing in the flow passage unit; a signal processing unit to receive an electrical signal of the scattered light for each particle to process the electrical signal, and output a signal-processed result as a pulse for each particle; and an information analysis unit to divide the strength level of the pulse for each particle into a plurality of channels, and use an air flow, particle density, the number of particles for each channel, and particle sizes to obtain a concentration of the particles as follows. (PM represents the concentration of the particles; (i) represents a channel number; (n) represents a positive integer as the total number of channels, (np_i) represents the number of particles having sizes belonging to the i^th channel; (V_i) represents the volume of the particles; ρ represents the density of the particles; (F) represents the air flow; and (r_i) represents the size of the particles belonging to the i^th channel.)

Description

Apparatus for sensing particle

An embodiment relates to a particle sensing device.

Generally, in a conventional dust sensing apparatus for sensing particles such as dust, light is irradiated toward the dust in the direction of the optical axis, and light scattered in the dust is sensed from the side of the optical axis to obtain information on dust. One example of such a conventional lateral dust sensing device is disclosed in U.S. Patent No. 7,038,189 (Registered May 2, 2006).

When the light scattered in the dust is sensed from the side in the optical axis direction, it is difficult to sense particles having a small size, for example, a size of 1 mu m or less because the intensity of the sensed scattered light is weak, ) Also suffers from a narrow problem.

Further, in the case of the conventional lateral type dust sensing apparatus, a path through which air including dust is formed by heat flow has a limit such that the area where the particles flow is larger than the light collecting area. As a result, the number of unmeasured particles increases and the accuracy of sensing the particles is lowered, as well as the overall size of the dust sensing device is increased due to the arrangement of heat sources for heat flow. For example, in the case of the conventional lateral type dust sensing apparatus, the dust measurement error is about 30%, which is very high.

Further, in the case of the conventional lateral type dust sensing apparatus, the intensity of scattered light is not high because the light scattered from the dust is sensed from the side. Therefore, there is a problem that more power is required to increase the intensity of the scattered light.

In addition, in the case of the conventional lateral dust sensing apparatus, it is impossible to count the number of all the dusts due to the structural limit of the passage through the particles.

In order to obtain the concentration of dust in a conventional dust sensing apparatus, an air flow is formed in the sensor by a heater (not shown) or a fan (not shown), and the amount of dust passing through the sensor is measured in a range of / / . At this time, in the equation for determining the concentration of dust, m3 is fixed, so that the concentration of dust can not be accurately measured.

Particularly, when a heater is installed to form an air flow by the heat flow in the path of dust, the cost is incurred because the sensor must be recalibrated, and the error may be up to 90% due to the change of the air flow rate around the sensor . To improve this, it is also possible to generate airflow by using a fan in a path where dust passes without using a heater. When the fan is placed, the density of the dust can be more accurate than when using the heater, but the price of the sensor can be increased. This is because approximately 50% of the manufacturing cost of the sensor is the price of the fan.

In addition, if the sensor fan or heater is used for a long time, the accuracy of the dust concentration may be impaired due to aging of these devices.

The embodiment is to provide a particle sensing device capable of accurately measuring the concentration of particles.

According to an embodiment of the present invention, there is provided a particle sensing apparatus including: a light emitting unit emitting light; A flow path disposed below the light emitting part in a first direction intersecting the optical axis of the light emitting part and through which air including particles flows; A light receiving portion disposed on the optical axis below the flow path portion and adapted to inject scattered light for each particle flowing in the flow path portion; A signal processing unit for receiving and processing an electric signal of light emitted by the particle from the light receiving unit and outputting the signal processed result as a particle-specific pulse; And the intensity of a level that the particle-specific pulse can have is divided into a plurality of channels, and the concentration of the particles is determined by using the flow rate of the air, the density of the particles, And may include an information analyzing section obtained as follows.

Here, PM denotes the concentration of the particles, i denotes a channel number, n denotes a positive integer of 2 or more as the total number of channels, NP _i denotes the number of particles belonging to the i-th channel, V _i represents the volume of the particle, p represents the density of the particle, F represents the flow rate of the air, and r _i represents the size of the particle belonging to the i-th channel.

For example, the flow path portion may include a flow path inlet portion into which the air flows; A flow path outlet through which the air flows; And a scattering portion located in the optical axis between the light emitting portion and the light receiving portion and between the flow path inlet portion and the flow path outlet portion and scattering light emitted from the light emitting portion by the particles.

For example, the width of the light irradiated to the scattering portion in the first direction is 2 mm to 6 mm, and the height of the scattering portion in the second direction parallel to the optical axis from the light emitting portion to the light receiving portion is 1 mm to 2 mm Lt; / RTI >

For example, the minimum height of the scattering portion in the second direction parallel to the optical axis from the light emitting portion to the light receiving portion may be smaller than the width of the light irradiated to the scattering portion in the first direction.

For example, the intensity of light incident on the scattering unit may have a constant square shape in the first direction within the scattering unit.

For example, the particle sensing apparatus may further include a power supply unit that supplies power to the light emitting unit under the control of the information analysis unit, and the information analysis unit controls the power supply unit to turn on the light emitting unit at a predetermined frequency, The light emitted from the light emitting portion can be modulated.

For example, the signal processing unit may include a preprocessing unit for converting an electrical signal of a current type received from the light receiving unit into a voltage form, filtering the high-frequency component of the converted result, and then amplifying the filtered high-frequency component firstarily; And a post-processing unit for filtering the high-frequency components of the signal output from the preprocessing unit, and then amplifying the high-frequency components of the signal output from the preprocessing unit, and outputting the pulses as the per-particle pulses.

For example, the pre-processor may include a current / voltage converter for converting an electrical signal of a current type output from the light-receiving unit into a voltage form; A first high pass filter for filtering high frequency components of the signal converted into the voltage form; And a first amplifying unit amplifying the output of the first high-pass filter.

For example, the post-processing unit may include a second high-pass filter for filtering a high-frequency component of a result amplified by the first amplifying unit; And a second amplifying unit amplifying the output of the second high-pass filter.

For example, the signal processing unit may include an analog-to-digital converter that converts analog-type particle-by-particle pulses into digital form and outputs the pulses to the information analysis unit.

For example, the information analyzer may include: a channel classifier for classifying intensity levels of the pulses per particle output from the signal processor into first through n-th channels; A particle size determination unit that determines a size of the particle corresponding to each pulse in the particle-specific pulse output from the signal processing unit; A counting unit for counting the number of particles for each of a plurality of channels by using the size of the particles corresponding to each pulse in the particle-by-particle pulses determined by the particle size determining unit; A flow rate calculation unit for calculating a flow rate of the air; And calculating a concentration of the particles using the counted number of particles, the representative value (r _i ) of the particle size assigned to each of the plurality of channels, the particle density (rho), and the flow rate And a concentration calculation unit.

For example, the particle size determination unit may determine the particle size using the following function.

r? f (PA)

Where PA represents the maximum intensity of each pulse in the particle-specific pulse and r represents the size of the particle corresponding to each pulse in the particle-by-particle pulse. For example, the function may be an n-order linear fitting equation or a logarithmic function.

For example, the counting unit may count the number of particles per a plurality of channels as follows.

r _i? r (ch _i ) <r <r (ch _{i + 1} )

R (ch _{i + 1} ) represents the size of a particle determined in advance for the ( _{i + 1} ) -th channel, r (ch _i ) represents the size of the particle determined using the i- Lt; RTI ID = 0.0 &gt; a &lt; / RTI &gt; particle size.

For example, the flow rate calculator may calculate the flow rate of the air using the width of a pulse belonging to an arbitrary channel among n channels as follows.

Here, T represents the width of the pulse corresponding to the arbitrary channel, and a and b represent the previously obtained variables.

For example, the arbitrary channel may include a first channel corresponding to the smallest level of intensity that the per-particle pulse can have, and a second through n-th channel &Lt; / RTI &gt;

Since the particle sensing apparatus according to the embodiment is able to accurately measure the concentration of particles in any fluid within a certain range and does not require a fan since the influence of winds around the particle is small, the particle sensing apparatus can be manufactured at low cost, The conventional problem that the noise caused by the fan is not generated and the measurement accuracy of the particle concentration is lowered due to the aging of the fan is solved and the long-term reliability can be obtained, and the electric noise And is not affected by the flow velocity, so that it has improved installation freedom.

1 is a schematic block diagram for explaining the concept of a particle sensing apparatus according to an embodiment.
Figure 2 shows an exemplary profile of scattered light scattered by particles.
Figure 3 shows a cross-sectional view of one embodiment of the particle sensing device shown in Figure 1;
4 is an enlarged cross-sectional view of the 'A1' portion in order to explain the flow path portion shown in FIG.
Figure 5 shows a cross-sectional view of another embodiment of the particle sensing device shown in Figure 1;
6 is an enlarged cross-sectional view of the 'A2' portion in order to explain the flow path portion shown in FIG.
Figure 7 shows a cross-sectional view of another embodiment of the particle sensing device shown in Figure 1;
8 is an enlarged cross-sectional view of the portion 'A3' to illustrate the flow path portion shown in FIG.
9 is an enlarged cross-sectional view of the portion 'B' shown in FIG.
FIG. 10 shows a planar shape of an embodiment of the light sensing unit shown in FIG.
11 shows a planar shape according to another embodiment of the light sensing unit shown in FIG.
FIG. 12 shows a planar shape according to still another embodiment of the light sensing unit shown in FIG.
FIG. 13 shows a planar shape according to still another embodiment of the light sensing unit shown in FIG.
FIG. 14 shows a planar shape according to still another embodiment of the light sensing unit shown in FIG.
FIG. 15 shows a planar shape according to another embodiment of the light sensing unit shown in FIG.
FIG. 16 shows a planar shape according to another embodiment of the light sensing unit shown in FIG.
FIG. 17 shows a planar shape according to another embodiment of the light sensing unit shown in FIG.
18A and 18B are diagrams for explaining the prediction of the shape of particles using a plurality of sensing segments.
19A and 19B show the planar shape of the light incident on the photodiode.
Fig. 20 shows a cross-sectional view according to another embodiment of the particle sensing apparatus shown in Fig. 1. Fig.
Figure 21 shows a side view of the particle sensing device shown in Figure 20.
22 is a top perspective view of the particle sensing apparatus shown in Fig.
Fig. 23 shows a left perspective view of the particle sensing device shown in Fig. 20, respectively.
24 is a plan view cut along the line I-I 'shown in FIG.
25 is an enlarged cross-sectional view of a portion 'C' shown in FIG.
26 is an enlarged cross-sectional view of the portion 'D' shown in FIG.
Fig. 27 is a view showing a part of the particle sensing apparatus shown in Fig. 1. Fig.
28A and 28B are graphs showing the intensity of light incident on the scattering portion.
29 (a) and 29 (b) show graphs of particles passing through the scattered light at a first velocity and graphs of electrical signals of light scattered by the particles, respectively.
30 (a) and 30 (b) show graphs of the states of the particles P passing through the light irradiated to the scattering portion at the second speed and the electric signals of the light scattered by the particles, respectively.
31 shows a block diagram according to an embodiment of the signal processing unit.
Fig. 32 shows a circuit diagram according to one embodiment of the preprocessing unit and post-processing unit shown in Fig.
33 shows an output waveform at each point of the preprocessing unit and the post-processing unit shown in Fig.
34A and 34B are graphs showing examples of pulses per particle provided from the signal processing unit to the information analysis unit.
FIG. 35 is a graph showing an enlarged view of a part of the waveform shown in FIG. 34A.
36 is a block diagram of an information analyzing unit according to an embodiment of the present invention;
37 is a flowchart for explaining a particle concentration calculation method performed by the information analysis unit;

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings in order to facilitate understanding of the present invention. However, the embodiments according to the present invention can be modified into various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. Embodiments of the invention are provided to more fully describe the present invention to those skilled in the art.

In the description of the present embodiment, in the case of being described as being formed "on or under" of each element, the upper (upper) or lower (lower) on or under includes both the two elements being directly in contact with each other or one or more other elements being indirectly formed between the two elements.

Also, when expressed as "on" or "on or under", it may include not only an upward direction but also a downward direction with respect to one element.

It is also to be understood that the terms "first" and "second," "upper / upper / upper," and "lower / lower / lower" But may be used to distinguish one entity or element from another entity or element, without necessarily requiring or implying an order.

Hereinafter, a particle sensing apparatus 100 (100A to 100D) according to an embodiment will be described with reference to the accompanying drawings. For convenience of explanation, the particle sensing apparatus 100 (100A to 100D) is described using a Cartesian coordinate system (x-axis, y-axis, z-axis), but it can be explained by other coordinate systems. According to the Cartesian coordinate system, the x-axis, the y-axis and the z-axis are orthogonal to each other, but the embodiment is not limited to this. That is, according to another embodiment, the x-axis, the y-axis, and the z-axis may intersect with each other.

1 is a schematic block diagram for explaining the concept of the particle sensing apparatus 100 according to the embodiment and includes a light emitting unit 110, a channel unit 120, a light receiving unit 130, a light absorbing unit 140 A signal processing unit 150, a power supply unit 152, a communication unit 154, and an information analysis unit 160.

Referring to FIG. 1, the light emitting unit 110 may emit light, and may include a light source unit 112, a lens unit 114, and a light emitting case 116.

The light source unit 112 serves to emit the first light L1 and may include at least one light source. The light source included in the light source unit 112 may be at least one of a light emitting diode (LED) or a laser diode (LD). The light source unit 112 may include at least one of a light source, But not limited to. For example, the light source that implements the light source 112 may be a blue LED having high linearity, a high-brightness LED, a chip LED, a high-lux LED, or a power LED, but the light source according to the embodiment is not limited to a specific LED .

If the light source unit 112 is implemented by an LED, light of a visible light wavelength band (for example, 405 nm to 660 nm) or an infrared (IR) wavelength band (for example, 850 nm to 940 nm) . &Lt; / RTI &gt; In addition, when the light source unit 112 is implemented as an LD, it can emit light in a red (blue) wavelength band (for example, 450 nm to 660 nm). However, the embodiment is not limited to a specific wavelength band of the first light L1 emitted from the light source section 112. [

Also, the intensity of the third light L3 emitted from the light emitting portion 110 may be higher than 3000 mcd, but the embodiment is not limited to the specific intensity of the third light L3 emitted.

The light source of the light emitting unit 110 may be packaged in a SMD (Surface Mount Device) type or a lead type. Here, the SMD type means a packaging type in which a light source of the light emitting portion 112A is mounted on a printed circuit board (PCB) through soldering, as shown in FIG. In addition, the lead type means a packaging type in which a lead that can be connected to a PCB electrode protrudes from a light source. However, the embodiment is not limited to a specific packaging form of the light source.

In addition, when the light emitting unit 110 is implemented as an LD, the LD may be a TO Can type packaged with metal and may consume 5 mW or more of power, but the embodiment is not limited thereto.

The lens unit 114 may be disposed on the optical axis LX between the light source unit 112 and the first opening OP1. That is, the lens unit 114 may be disposed on a path through which the first light L1 passes from the light source unit 112 toward the first opening OP1. The lens unit 114 functions to condense the first light L1 emitted from the light source unit 112 into the first opening OP1 (L2). The lens unit 114 may also convert the first light L1 emitted from the light source unit 112 into parallel light L2. For this purpose, the lens portion 114 may include only one lens or may include a plurality of lenses arranged on the optical axis LX. The material of the lens portion 114 may be the same as that applied to a general camera module or an LED module.

The light emitting case 116 receives the light source unit 112 and the lens unit 114 and forms a first opening OP1. In the case of FIG. 1, the light emitting case 116 is illustrated as being separate from the top portion 172 of the housing 170, but the embodiment is not limited thereto. That is, the light emitting case 116 may be integrally formed with the top portion 172 of the housing 170, as illustrated in FIGS. 20, 21, 22, or 23 described later. In this case, the light emitting case 116 can be omitted.

Further, the light emitting case 116 may include a first opening OP1. The first opening OP1 is formed by the second light L2 emitted from the light source unit 112 and passing through the lens unit 114 into the scattering part SS of the flow path part 120 (L3), and may be disposed on the optical axis LX of the light emitting portion 110. [ The scattering unit SS will be described later in detail when the flow path unit 120 is described.

The first opening OP1 may have an area corresponding to a view angle of the first light L1 emitted from the light source unit 112. [ Generally, the emission angle of the LED, which may be the light source 112, is about 15 degrees when the luminous intensity falls to 50%. Thus, the light of the desired intensity can be emitted through the first opening OP1 even if the area of the first opening OP1 is not large because the power of the beam is large at the center. However, if the light emission angle is large, if the area of the first opening OP1 is determined so that the third light L3 having a desired intensity is emitted from the light emitting portion 110, light loss occurs and the intensity of the light is weakened have. Therefore, the light emission angle can be determined in consideration of this. For example, when the first opening OP1 has a circular planar shape, if the diameter of the first opening OP1 is larger than 15 mm, the size of the particle sensing device 100 becomes large and light noise may be caused have. The diameter of the first opening OP1 may be from 2 mm to 15 mm, for example from 3 mm to 10 mm, preferably from 4 mm to 6 mm, for example 5.5 mm, although the embodiment is not limited in this respect .

The flow path portion 120 may be disposed in a first direction (e.g., a y-axis direction) intersecting the optical axis LX of the light emitting portion 110 below the light emitting portion 110, Provides a flow path. The air including the particles can flow in the IN1 direction towards the inlet IH of the flow path portion 120 and can be discharged in the OUT1 direction through the outlet OH of the flow path portion 120. [ For example, particles may be particles that float in the air, may be dust or smoke, and embodiments are not limited to particular forms of particles.

Particles included in the air flowing in the direction IN1 through the inlet IH of the flow path portion 120 are scattered by the third light L3 emitted from the light emitting portion 110, And scattered fourth light L4 (hereinafter, referred to as scattered light) may be provided to the light receiving unit 130. [

1, the flow path unit 120 is illustrated as being spaced apart from the light emitting unit 110 and the light receiving unit 130, respectively. However, this is to explain the concept of the particle sensing apparatus 100 according to the embodiment. That is, the flow path unit 120 may be disposed in contact with the light emitting unit 110 and the light receiving unit 130, respectively, as in the particle sensing apparatuses 100A to 100D described below according to the manner in which the flow path unit 120 is implemented.

The particle sensing apparatus 100 according to the embodiment shown in FIG. 1 may include a fan 180 and may not include a fan 180. The fan 180 serves to induce the flow of air in the flow path portion 120. That is, the fan 180 maintains a constant flow rate of the air within the flow path portion 120. For this purpose, the fan 180 may be disposed adjacent to the flow path portion 120 in a first direction (e.g., a y-axis direction) in which air flows. For example, as shown in FIG. 1, the fan 180 may be disposed at the outlet (OH) side of the flow path portion 120, but the embodiment is not limited thereto. That is, the embodiment is not limited to the specific arrangement position of the fan 180, as long as it can induce the flow of air in the flow passage portion 120. [

For example, the flow path portion 120 may be implemented so that the air containing particles in the flow path portion 120 maintains a flow rate of 1 to 10 psi, but the embodiment is not limited thereto.

The light receiving unit 130 receives the fourth light L4 passing through the channel unit 120 and may be disposed on the optical axis LX under the channel unit 120. [ Here, the fourth light L4 having passed through the flow path portion 120 may include at least one of scattered light and scattered light.

Figure 2 shows an exemplary profile of scattered light scattered by particles (P).

Referring to FIG. 2, scattered light may mean light scattered by particles P included in air passing through the flow path portion 120 by the third light L 3 emitted from the light emitting portion 110. The non-scattered light means light that the third light L3 emitted from the light emitting portion 110 travels to the light receiving portion 130 without being scattered by the particles P passing through the flow path portion 120. [

The light receiving unit 130 receives scattered light and can provide an electrical signal of the received light to the signal processing unit 150.

The light absorbing part 140 absorbs the fifth light L5 that has passed through the light receiving part 130 and may be disposed on the optical axis LX under the light receiving part 130. [ The light absorbing part 140 may correspond to a kind of dark room that absorbs unnecessary light which is not received by the light receiving part 130 but travels straight (hereinafter, 'main light').

The housing 170 serves to receive the light emitting portion 110, the flow path portion 120, the light receiving portion 130, and the light absorbing portion 140.

The housing 170 may further receive the signal processing unit 150, the power supply unit 152, the communication unit 154, and the information analysis unit 160. However, the embodiment is not limited to this. According to another embodiment, the signal processing unit 150, the power supply unit 152, the communication unit 154, and the information analysis unit 160 are arranged in a separate base substrate (not shown) instead of being housed in the housing 170 Or received). Here, the base substrate may be a type of printed circuit board to which the particle sensing device 100 shown in FIG. 1 is attached, and which receives electrical signals output from the light receiving unit 130.

For example, the housing 170 may include a top portion 172, a middle portion 174, and a bottom portion 176. The middle part 174 is a part capable of accommodating the flow path part 120 and the fan 180. The bottom part 176 is a part capable of receiving the light emitting part 110, Absorbing part 140 is a part that can accommodate the absorbing part 140.

In the case of FIG. 1, the intermediate portion 174 of the housing 170 and the flow path portion 120 are illustrated as being different, but the embodiment is not limited thereto. According to another embodiment, the flow path portion 120 may be formed by the intermediate portion 174 of the housing 170 as in the particle sensing devices 100A to 100D described later.

Hereinafter, embodiments 100A to 100D of the particle sensing apparatus 100 shown in FIG. 1 will be described with reference to the accompanying drawings.

First, the particle sensing apparatus 100A according to the first embodiment will be described with reference to FIGS. 3 and 4 as follows.

FIG. 3 shows a cross-sectional view of one embodiment 100A of the particle sensing device 100 shown in FIG. For the sake of clarity, FIG. 3 shows the progress of the light as shading (L).

3 includes a light emitting portion 110A, a flow path portion 120A, a light receiving portion 130A, a light absorbing portion 140 and housings 172 and 176, and the fan 180, As shown in FIG. The signal processing unit 150, the power supply unit 152, the communication unit 154, and the information analysis unit 160 shown in FIG. 1 are omitted from FIG.

The light emitting portion 110A, the flow path portion 120A, the light receiving portion 130A, the light absorbing portion 140, the housings 172 and 176, and the fan 180 shown in FIG. 3 correspond to the light emitting portion 110 The light receiving unit 130, the light absorbing unit 140, the housings 172 and 176, and the fan 180, the description of the overlapping portions will be omitted.

Referring to FIG. 3, the light source unit 112A includes only one light source, and the lens unit 114A includes only one lens. The lens 114A is disposed on the optical axis LX between the light source 112A and the first opening OP1 and functions to condense the light emitted from the light source 112A into the first opening OP1. However, the embodiment is not limited to this. That is, according to another embodiment, the lens portion 114A may include a plurality of lenses.

4 is an enlarged cross-sectional view of the 'A1' portion in order to explain the flow path portion 120A shown in FIG. 3. For convenience of explanation, the illustration of the fan 180 shown in FIG. 3 is omitted in FIG.

3 and 4, the flow path portion 120A includes a flow path inlet portion FI, a first flow path intermediate portion FII1, a scattering portion SS, a second flow path middle portion FII2, FO).

The flow path inlet portion FI may include an inlet port IH and a first path as a portion into which air that may contain particles P may flow. Here, the inlet IH corresponds to the inlet of the flow path portion 120 into which air flows from the outside in the IN1 direction, and the first path corresponds to a path formed between the inlet IH and the first flow path middle portion FII1 .

The flow path outlet portion FO may include an outlet port OH and a second path as a portion through which air that may contain particles P may flow. The outlet port OH corresponds to the outlet of the flow path portion 120 through which the air flows out to the OUT1 direction and the second path corresponds to the path formed between the second flow path middle portion FII2 and the outlet port OH .

The scattering part SS is located on the optical axis LX between the light emitting part 110A and the light receiving part 130A and between the flow path inlet part FI and the flow path outlet part FO. The scattering portion SS provides a space in which the light emitted from the light emitting portion 110A is scattered by the particles P. [ To this end, the scattering portion SS is a portion in which the first opening OP1 and the second opening OP2 are formed in the flow paths 120 and 120A in the direction (for example, the z-axis direction) in which the light emitting portion 110A and the light receiving portion 130A face each other Can be defined as overlapping regions.

The first flow path middle portion FII1 is located between the flow path inlet FI and the scattering portion SS and the second flow path middle portion FII2 is located between the scattering portion SS and the flow path outlet portion FO .

The air containing the particles P flows through the flow path inlet FI and then proceeds to the scattering portion SS through the first flow path middle portion FII1 and then flows through the second flow path middle portion FII2 And then discharged through the flow path outlet (FO). As described above, the fan 180 can be disposed to facilitate the air containing the particles P to smoothly travel to the flow path portion 120A. For example, as shown in FIG. 3, the fan 180 may be disposed in the flow passage outlet FO or may be disposed adjacent to the outlet port OH of the flow passage outlet FO, as shown in FIG. 3 . Or according to another embodiment, the fan 180 may be disposed within the flow path inlet FI or adjacent the inlet IH.

The third light L3 emitted from the first opening OP while the air containing the particles P pass through the flow path portion 120A collides with the particles P at the scattering portion SS, It is scattered in the form of bar. At this time, in order to cause all the particles P passing through the scattering portion SS to strike by the third light L3 emitted from the light emitting portion 110A, the third light L emitted from the first opening OP1 L3 are suitable areas for forming light curtains in the scattering portion SS in a direction (e.g., the x-axis and the z-axis) intersecting with the first direction (e.g., the y-axis direction) The first opening OP1 may be provided.

The sectional area (for example, the area in the x-axis and the z-axis direction) of the flow path portion 120A may be smaller than the area of the first opening OP1 (for example, the area in the x- and y-axis directions) . 4, when the length of the first opening OP1 in the x-axis direction is equal to the length of the flow path portion 120A in the x-axis direction, the width D1 of the first opening OP1 May be greater than the height D2 of the flow path portion 120A. 4, when the first opening OP1 has a circular planar shape and the flow path portion 120A has a circular cross-sectional shape, the diameter D1 of the first opening portion OP1 is smaller than the diameter D1 of the flow path portion 120A. &Lt; / RTI &gt; The width (or diameter) D1 of the first opening OP1 may be 2 mm to 15 mm, for example, 3 mm to 10 mm, preferably 4 mm to 6 mm, for example, 5.5 mm, The embodiment is not limited to this.

As described above, when the cross-sectional area of the flow path portion 120A is smaller than that of the first opening portion OP1, the amount of air containing the particles P passing through the flow path portion 120A increases, The number of particles to be sensed in the particle sensing apparatus 100 (100A) can be increased.

In addition, the cross-sectional area of the flow path portion 120A may be smaller than the beam size of the light emitted from the first opening OP1. As a result, the amount of air containing the particles P passing through the flow path portion 120A increases, that is, the amount of particles passing through the flow path portion 120A increases, and a larger number of particles P . This will be described in more detail with reference to FIG. 27 to be described later.

As described above, since more information on the particles P can be obtained as the number of particles P passing through the flow path portion 120A increases, information on the particles P, particularly, The concentration can be more accurately analyzed.

In order to allow more particles P to pass therethrough, the flow path portion 120 shown in FIG. 1 may have various configurations other than the configurations shown in FIG. 3 and FIG.

Hereinafter, the particle sensing apparatus 100B according to the second embodiment will be described with reference to FIGS. 5 and 6. FIG.

5 is a cross-sectional view of another embodiment 100B of the particle sensing apparatus 100 shown in Fig. 1, and Fig. 6 is an enlarged view of the 'A2' portion in order to explain the flow path portion 120B shown in Fig. As a cross-sectional view, the illustration of the fan 180 shown in Fig. 5 is omitted in Fig. 6 for convenience of explanation.

The cross-sectional shapes of the flow path portion 120A shown in Fig. 3 and the flow path portion 120B shown in Fig. 5 are different from each other. Except for this, since the particle sensing apparatus 100B shown in FIG. 5 is the same as the particle sensing apparatus 100A shown in FIG. 3, the duplicate description will be omitted. For example, the definition of the scattering unit SS described above with reference to FIG. 4 can also be applied to the flow path portion 120B shown in FIG.

In the case of FIGS. 3 and 4, the flow path opening portion FI, the flow path opening portion, and the flow path portion are formed in the direction (for example, the x-axis direction and the z- The sectional areas of the first flow path middle portion FII1, the scattering portion SS, the second flow path middle portion FII2, and the flow path outlet portion FO are constant.

On the other hand, the cross-sectional area of the first flow path intermediate portion FII1 in the direction (for example, the x-axis and the z-axis direction) intersecting with the first direction (for example, SS, and the cross-sectional area of the second flow path middle portion FII2 may include a portion that increases as the distance from the scattering portion SS increases.

For example, as shown in Figs. 5 and 6, the first (e.g., the x-axis and the z-axis) directions intersecting with the first direction Sectional area of the middle passage FII1 decreases and becomes constant as it approaches the scattering section SS and the sectional area of the middle portion of the second flow passage FII2 increases constantly as the distance from the scattering section SS increases. 5 or 6, although not shown, a direction intersecting with a first direction (e.g., a y-axis direction) in which air flows (for example, an x-axis and a z-axis direction) The cross sectional area of the first flow path intermediate portion FII1 gradually decreases as the scattering portion SS approaches and the cross sectional area of the second flow path middle portion FII2 continues to increase as the distance from the scattering portion SS increases have.

3 and 4, in a direction (for example, the x-axis and the z-axis direction) intersecting with the first direction in which air flows (for example, the y-axis direction) Sectional area of each of the flow path portion FI and the flow path outlet portion FO may be larger than the cross-sectional area of the scattering portion SS.

In the flow paths 120A and 120B shown in Fig. 4 and Fig. 6, an opening area in which the first flow path middle portion FII1 (or the second flow path middle portion FII2) and the scattering portion SS communicate The area of the first opening OP1 (for example, the area in the x-axis and the y-axis direction) is defined as the second opening OP2 in the first direction (for example, the y- Sectional area of the second opening OP2 in the direction (for example, the x-axis and the z-axis direction) intersecting the first opening OP2.

4 and 6, when the length of the first opening OP1 in the x-axis direction is equal to the length of the second opening OP2 in the x-axis direction, the first opening OP1, The width D1 of the second opening OP2 may be larger than the height D4 of the second opening OP2. 4 and 6, when the first opening OP1 has a circular planar shape and the second opening OP2 has a circular cross-sectional shape, the diameter D1 of the first opening OP1, May be larger than the diameter D4 of the second opening OP2.

When the flow path portion 120B has a cross-sectional shape as shown in Figs. 5 and 6, a larger number of particles P can be obtained due to the change in sectional area of the first and second flow path middle portions FII1 and FII2, Can pass through the flow path portion 120B, and the accuracy of sensing the particles P can be increased.

Hereinafter, the particle sensing apparatus 100C according to the third embodiment will be described with reference to FIGS. 7 and 8 as follows.

7 is a cross-sectional view of another embodiment 100C of the particle sensing apparatus 100 shown in Fig. 1, and Fig. 8 is an enlarged view of the 'A3' portion in order to explain the flow path portion 120C shown in Fig. As a sectional view, for the convenience of explanation, the illustration of the fan 180 shown in Fig. 7 is omitted in Fig.

The cross-sectional shapes of the flow path portion 120A shown in Fig. 3 and the flow path portion 120C shown in Fig. 7 are different from each other. Except for this, since the particle sensing apparatus 100C shown in FIG. 7 is the same as the particle sensing apparatus 100A shown in FIG. 3, a duplicate description will be omitted.

In the case of FIGS. 3 and 4, the flow path opening portion FI, the flow path opening portion, and the flow path portion are formed in the direction (for example, the x-axis direction and the z- The sectional areas of the first flow path middle portion FII1, the scattering portion SS, the second flow path middle portion FII2, and the flow path outlet portion FO are constant.

On the other hand, in the case of FIGS. 7 and 8, in the direction (for example, the x-axis and the z-axis direction) intersecting with the first direction (for example, (FII1) decreases as it approaches the scattering section (SS) and then increases. Further, the cross-sectional area of the second flow path intermediate portion FII2 in the direction (for example, the x-axis and the z-axis direction) intersecting with the first direction (for example, SS), and then increases.

In addition, the smallest cross-sectional area in the direction intersecting the first direction in which the air flows in the first intermediate passage portion FII1 (or the second intermediate passage portion FII2) of the passage portion 120C shown in Fig. 8 The area of the first opening OP1 (for example, the area in the x-axis direction and the y-axis direction) is defined as the second opening OP2 in the first direction in which the air flows (for example, sectional area of the second opening OP2 in a direction (for example, the x-axis and the z-axis direction) intersecting the first opening OP2.

8, when the length of the first opening OP1 in the x-axis direction and the length of the second opening OP2 in the x-axis direction are equal to each other, the width of the first opening OP1 D1 may be greater than the height D4 of the second opening OP2. 8, when the first opening OP1 has a circular planar shape and the second opening OP2 has a circular cross-sectional shape, the diameter D1 of the first opening OP1 is larger than the diameter D1 of the second opening OP1, Can be larger than the diameter D4 of the opening OP2.

For example, the height (or diameter) D4 of the second opening OP2 shown in Figs. 4, 6 and 8 may be 1 mm to 10.0 mm, for example, 1 mm to 5.0 mm, preferably 1 Mm to 2.0 mm, for example, 2 mm, but the embodiment is not limited to this. As described above, according to the embodiment, since the height (or diameter) D4 of the second opening OP2 is small, the size of the entire particle sensing apparatuses 100A to 100C can be reduced.

In order to allow a larger number of particles to pass through the flow path portions 120 (120A, 120B, and 120C), there is no change in the volume of the flow rate of the air passing through the flow path portion 120. [ 7 and 8, when a double nozzle (DN) structure is formed by the second opening OP2, the volume change of the flow rate of the air passing through the flow path portion 120C is The flow rate of the air can be adjusted so as to be easy to measure, and the accuracy of sensing the particles P can be increased. For example, since a bottleneck phenomenon is created by the double nozzle structure, a larger number of particles P can pass through the flow path portion 120C, and the accuracy of sensing the particles P can be increased.

The structures of the flow paths 120A, 120B, and 120C shown in Figs. 3 to 8 are merely one example. That is, the embodiment is not limited to the specific example of the flow path portion 120, as long as more air can flow through the flow path portions 120A, 120B, and 120C.

Hereinafter, the detailed features of the flow paths 120 (120A, 120B, and 120C) will be described as follows.

As illustrated in FIGS. 6 and 8, inlets IH and IH extend in a direction (for example, the x-axis and the z-axis direction) intersecting with the first direction The sectional area of each of the outlets OH may be smaller than the plane of the first opening OP1 and larger than the sectional area of the second opening OP2. Alternatively, the cross-sectional area of each of the inlet port IH and the outlet port OH may be larger than that of the first opening OP1, and the cross-sectional area of the second opening OP2 may be smaller than that of the first opening OP1.

Alternatively, the first path of the flow path inlet portion FI and the flow path outlet end portion of the flow path outlet portion (for example, the flow path outlet portion) may be formed in a direction intersecting with the first direction The largest cross-sectional area of each of the second paths of the first openings FO may be smaller than the area of the first openings OP1 and larger than the cross-sectional area of the second openings OP2. Alternatively, the cross-sectional area of each of the inlet port IH and the outlet port OH may be larger than that of the first opening OP1, and the cross-sectional area of the second opening OP2 may be smaller than that of the first opening OP1.

For example, when the x-axis length of each of the inlet IH and the outlet OH is equal to the x-axis length of each of the first opening OP1 and the second opening OP2, the inlet IH and the outlet OH The height D2 in the z-axis direction is smaller than the width D1 in the y-axis direction of the first opening OP1 and larger than the height D4 in the z-axis direction of the second opening OP2 .

For example, when the flow path inlet portion FI, the flow path outlet portion FO, and the second opening portion OP2 each have a circular cross-sectional shape and the first opening portion OP1 has a circular planar shape, The diameter D2 of each of the inlet port IH and the outlet port OH may be smaller than the diameter D1 of the first opening OP1 and larger than the diameter D4 of the second opening OP2.

The height (or diameter) D2 of the inlet IH may be from 1 mm to 15 mm, for example from 2 mm to 8 mm, preferably from 3 mm to 4 mm, for example 3.5 mm, Is not limited to this. The height (or diameter) of the outlet OH may also be 5 mm to 25 mm, for example 8 mm to 15 mm, preferably 10 mm to 12 mm, for example 11 mm, But is not limited thereto.

Or, for example, when the x-axis length of each of the inlet IH and the outlet OH is equal to the x-axis length of each of the first opening OP1 and the second opening OP2, The highest height in the z-axis direction of each of the paths may be greater than the width D1 in the y-axis direction of the first opening OP1 and greater than the height D4 in the z-axis direction of the second opening OP2.

For example, when each of the flow path inlet portion FI, the flow path outlet portion FO and the second opening portion OP2 has a circular cross-sectional shape and the first opening portion OP1 has a circular planar shape, The largest diameter in each of the first path and the second path may be larger than the diameter D1 of the first opening OP1 and larger than the diameter D4 of the second opening OP2.

Meanwhile, the light receiving unit 130 may have various structures in order to accurately detect light scattered by the particles P. The light receiving unit 130A shown in FIGS. 3, 5, and 7 corresponds to the light receiving unit 130 shown in FIG.

9 is an enlarged cross-sectional view of the portion 'B' shown in FIG.

3 and 9, the light receiving unit 130A may include a light transmitting member 132 and a light sensing unit 134. [ The light receiving portion 130A may further include a light guide portion 136A, but in some cases, the light guide portion 136A may be omitted.

Correlated features of the units 132, 134, and 136A are as follows.

The light-transmissive member 132 may be formed of a material capable of transmitting light, and may be embodied as glass, for example. The light transmitting member 132 may include a first surface 132-1 and a second surface 132-2. The first surface 132-1 corresponds to the top surface (i.e., the top surface) of the light transmitting member 132 facing the scattering section SS and the second surface 132-2 corresponds to the first surface 132-1. (That is, the bottom surface) of the light transmitting member 132 as the opposite surface of the light transmitting member 132. [

The light sensing part 134 and the light guide part 136A may be disposed around the optical axis of the light transmitting member 132. [ The light sensing part 134 and the light guide part 136A may be disposed on mutually opposing surfaces of the light transmitting member 132. [ 9, the light sensing part 134 is disposed on the second surface 132-2 of the light transmissive member 132, and the light guiding part 136A is disposed on the second surface 132-2 of the light transmissive member 132. [ And may be disposed on the first surface 132-1. 9, the light sensing portion 134 is disposed on the first surface 132-1 of the light transmitting member 132 and the light guiding portion 136A is disposed on the second surface 132-1 of the light transmitting member 132, May be disposed on the surface 132-2. 9, the light sensing portion 134 is disposed on the second surface 132-2 of the light transmissive member 132, and the light guide portion 136A is disposed on the second surface 132-2 of the light transmissive member 132, Plane 132-1, but in the opposite case, the following description can be applied.

The light sensing unit 134 is disposed around the optical axis LX under the light transmissive member 132 and is scattered by the particles P at the scattering unit SS and then incident on the light receiving unit OP3 through the light receiving unit OP3. Can be sensed. The light receiving incidence portion will be described later.

FIG. 10 shows a planar shape of an embodiment 134A of the light sensing part 134 shown in FIG.

Referring to FIG. 10, the light sensing unit 134A may include a center portion 134-1 and a photodiode 134-2. The central portion 134-1 may be formed of a material having a light transmitting property and located on the optical axis LX so as to pass the main light passing through the scattering portion SS to the light absorbing portion 140. [ For example, the central portion 134-1 may be made of glass.

Further, the central portion 134-1 may cover the light entrance OPL of the light absorbing portion 140. As described above, when the center portion 134-1 covers the light entrance OPL, the penetration of foreign matter into the light absorbing portion 140 can be prevented, and the particles P passing through the scattering portion SS absorb light The flow of the particles P in the flow path portion 120 can be smooth and the measurement error can also be reduced.

In addition, when the photodiode 134-2 is disposed on the second surface 132-2 of the light transmitting member 132, damage to the photodiode 132-2 due to foreign matter can be prevented.

The photodiode 134-2 is disposed around the center portion 134-1 and serves to sense the light scattered by the particles P. [ The photodiode 134-2 corresponds to an active region for absorbing light in the structure of a general photodiode.

For example, the photodiode 134-2 can detect light in the 380 nm to 1100 nm wavelength band, but the embodiment is not limited to a specific wavelength band that can be detected by the photodiode 134-2. The photodiode 134-2 may have a sensitivity of 0.4 A / W at a wavelength band of 660 nm or a sensitivity of 0.3 A / W at 450 nm so that scattered light can be well sensed, Is not limited to this.

10, the width W1 of the light sensing portion 134A may be between 5 mm and 20 mm, for example between 7 mm and 15 mm, preferably between 8 mm and 10 mm, It does not.

The width W2 of the central portion 134-1 may be 3 mm to 18 mm, for example, 5 mm to 13 mm, and preferably 7 mm to 9 mm, but the embodiment is not limited to this.

In addition, the width W3 of the photodiode 134-2 on the plane may be 0.1 mm to 5 mm, for example, 1 mm to 3 mm, preferably 1.5 mm to 2.5 mm, Do not.

FIGS. 11-13 illustrate planar shapes of various embodiments 134B, 134C, and 134D of the light sensing portion 134 shown in FIG.

The planar shape of the photodiode 134-2 shown in Fig. 10 is circular, but the embodiment is not limited to this. For example, if the light sensing portion 134 can include the central portion 134-1, the photodiode 134-2 can have various planar shapes.

For example, as shown in Figs. 11 to 13, the planar shape of the photodiode 134-2 may be a polygonal annular shape. The planar shape of the photodiode 134-2 shown in Fig. 11 is a rectangular ring shape, the planar shape of the photodiode 134-2 shown in Fig. 12 is a square ring shape, and the photodiode 134-2 shown in Fig. 134-2 may have a triangular ring shape. Alternatively, although not shown, the planar shape of the photodiode 134-2 may be an elliptical annular shape.

Fig. 14 shows a planar shape of another embodiment 134E of the light sensing part 134 shown in Fig.

The photodiode 134-2 may include a plurality of sensing segments spaced apart from one another on the same plane. For example, as illustrated in FIG. 14, photodiode 134-2 may include a plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 spaced from one another .

Figs. 15 to 17 show planar shapes of still another embodiment (134F to 134H) of the light sensing part 134 shown in Fig.

A light sensing portion 134F having a rectangular annular plane as shown in Fig. 15, a light sensing portion 134G having a regular annular plane as shown in Fig. 16, a triangular annular planar surface 134G shown in Fig. 17, Each of the light sensing portions 134H having a plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 spaced apart from each other.

In addition, the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 illustrated in FIGS. 14 to 17 may be spaced apart at equal intervals or at different intervals. For example, the larger the spaced distance G of the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24, the higher the signal level and the greater the degree of design freedom. For example, the spacing G may be from 0.01 mm to 1 mm, for example from 0.1 mm to 0.5 mm, preferably from 0.15 mm to 0.25 mm, although the embodiments are not limited in this respect.

In addition, the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 may have the same planarity with each other, or may have different planarities.

In addition, the light sensing portions 134A to 134H illustrated in Figs. 10 to 17 may be arranged symmetrically on a plane, but the embodiments are not limited thereto. According to another embodiment, the light sensing portions 134A to 134H may be arranged asymmetrically in a plane.

Further, the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 may be arranged symmetrically or asymmetrically on a plane.

The widths W1, W2, and W3 shown in Figs. 11 to 17 may be those described in Fig.

For example, like the photodiode 134-2, each of the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 can detect light in the 380 nm to 1100 nm wavelength band , The embodiment is not limited to a specific wavelength band that can be detected in the plurality of sensing segments 134-21, 134-22, 134-23, 134-24. Each of the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 has a sensitivity of 0.4 A / W in a wavelength band of 660 nm, or a sensitivity of 0.4 Nm to 0.3 A / W, but the embodiment is not limited to this.

As illustrated in FIGS. 14 to 17, when the photodiode 134-2 is spaced apart from the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24, The controller 160 can predict the shape of the particle using the relative magnitude of the sensed result in each of the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24.

18A and 18B are views for explaining the prediction of the shape of the particles P using the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24.

18A, when the shape of the particles P is a symmetrical shape, for example, a spherical shape, the intensities of scattered light detected in the plurality of sensing segments 134-21, 134-22, 134-23, same. When the intensities of the light sensed by the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 are equal to each other, the information analysis unit 160 determines that the particles P have a symmetric shape .

On the other hand, referring to FIG. 18B, when the shape of the particles P is an asymmetric shape, for example, an unshaped shape, scattered light detected in the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 The strength of each is different. When the intensity of light sensed by the plurality of sensing segments 134-21, 134-22, 134-23, and 134-24 is different from each other, the information analysis unit 160 determines that the particle P has an asymmetric shape .

It goes without saying that, in order to predict various shapes of the particles, the number of the divided shapes of the plurality of sensing segments may vary.

The packaging form of the photodiodes 134-2 and 134-21 to 134-24 of the light receiving unit 130A described above may be implemented as an SMD type or a lead type as in the light source 112A of the light emitting unit 110A. However, the embodiment is not limited to the specific packaging form of the photodiodes 134-2, 134-21 to 134-24.

 19A and 19B show planar shapes of the light L incident on the photodiode 134. FIG.

For example, when the planar shape of the photodiode 134 is a rectangle as shown in FIG. 11, 12, 15, or 16, the planar shape of the light incident on the photodiodes 134B, 134C, 134F, As shown in Fig. 19A. Alternatively, when the planar shape of the photodiode 134 is circular as shown in Figs. 10, 14, 18A, or 18B, the planar shape of the light L incident on the photodiodes 134A, And may be circular as shown in FIG. 19B. 19A or 19B, the shape of at least one lens included in the lens portion 114 or the shape of at least one of the lenses of the first opening OP1 And the planar shape.

On the other hand, the light receiving incidence portion is disposed between the scattering portion SS and the light receiving portion 130A, and can adjust the amount of light incident on the light receiving portion 130A. 3, 5, and 7, the light receiving incidence portion may include a third opening OP3 disposed on the optical axis LX.

The third opening OP3 is an area suitable for entering 20% to 80% of the total amount of light scattered by the particles P in the scattering part SS to the light receiving part 130A Axial area).

For example, in the light scattered by the particles P from the scattering unit SS, the distance from the center of the scattering unit SS to the fifth opening OP5, which will be described later, with respect to the optical axis LX is 12 degrees , That is, 20% of the total light scattered in the particles P can be incident on the light receiving portion 130A when the predetermined angle? Shown in FIGS. 3, 5 and 7 is 24 °, 50% of the total light scattered in the particles P can be incident on the light receiving portion 130A when the angle? is 60 degrees (i.e., left and right 30 degrees with respect to the optical axis LX). In consideration of this, in the third opening OP3, the left angle of the light scattered by the particles P with respect to the optical axis LX, that is, the predetermined angle? Is 24 ° to 60 ° The light receiving portion 130A can have an area suitable for the light in the range of 30 degrees to the left and right with respect to the optical axis LX. As described above, it can be seen that the amount of light incident on the light receiving portion 130A can be adjusted by adjusting the area of the third opening OP3.

4, 6, and 8, the planar area (for example, the area in the x-axis and the y-axis direction) of the third opening OP3 is set to be planar (for example, the area in the x-axis direction and the y-axis direction). For example, when the third opening OP3 has a circular planar shape and the diameter D3 of the third opening OP3 is larger than 10 mm, the photodiodes 134-2, 134-21 to 134-24, Scattered light may be introduced into the photodiode, resulting in light noise. Further, when the diameter D3 of the third opening OP3 is smaller than 2 mm, the amount of scattered light received by the photodiodes 134-2 and 134-21 to 134-24 is reduced and the photodiodes 134-2 and 134-21 To 134-24 may be small in size. Therefore, the diameter D3 of the third opening OP3 may be from 1 mm to 12 mm, for example from 1 mm to 6 mm, preferably from 2 mm to 4 mm, for example 3 mm, It is not limited.

Referring again to FIG. 9, the light guide unit 136A guides the light scattered by the scattering unit SS to the light sensing unit 134. Referring to FIG. For this purpose, for example, the light guide portion 136A may include inner side walls 136-1 and 136-2 and outer side walls 136-3 and 136-4. If the inner partitions 136-1 and 136-2 have a circular planar shape, the inner partitions 136-1 and 136-2 are integral, and the outer partitions 136-3 and 136-4 are circular, The outer side walls 136-3 and 136-4 may be integral with each other.

The inner side walls 136-1 and 136-2 have a fourth opening OP4 overlapping the light entrance OPL of the light absorbing portion 140 in a direction parallel to the optical axis LX Can be defined. The scattered light having passed through the third opening OP3 proceeds to the fifth opening OP5 and the main light passing through the third opening OP3 passes through the third opening OP3, Lt; RTI ID = 0.0 &gt; OP1. &Lt; / RTI &gt; That is, the inner partitions 136-1 and 136-2 serve to separate the main light and the scattered light.

The height H1 of the inner side walls 136-1 and 136-2 may be 1 mm to 15 mm, for example, 2 mm to 10 mm, preferably 3 mm to 6 mm, for example, 5 mm, Examples are not limited to these.

The outer side walls 136-3 and 136-4 are connected to the fifth opening OP5 overlapping the photodiode 134-2 in the direction parallel to the optical axis LX -1, 136-2).

The width W4 of the fifth opening OP5 may be 0.1 mm to 6 mm, for example, 0.5 mm to 3 mm, preferably 0.8 mm to 1.5 mm, for example, 1 mm, Do not.

When the inner partitions 136-1 and 136-2 and the outer partitions 136-3 and 136-4 are disposed as described above, as indicated by the arrow in FIG. 3, the third part OP3 The main scattered light can proceed to the photodiode 134-2 of the light sensing part 134 and the main light incident on the third opening OP3 can travel toward the light absorbing part 140. [

Meanwhile, the light receiving portion 130A may further include the sensing support portion 138, but in some cases, the sensing support portion 138 may be omitted.

The sensing support portion 138 serves to support the light sensing portion 134 and may be implemented separately from the bottom portion 176 of the housing 170 as shown in FIG. And the bottom portion 176 of the first embodiment.

3, the light absorbing part 140 may include an absorption case 142 and a protrusion 144. The light absorbing part 140 may be formed of a transparent material. The absorption case 142 defines a light entrance OPL through which the light passing through the light receiving unit 130A is incident and serves to receive the main light passing through the light receiving unit 130A. The width (for example, the width in the y-axis direction) of the light entrance OPL may be 2 mm to 15 mm, for example, 3 mm to 10 mm, preferably 4 mm to 6 mm, However, the embodiment is not limited to this.

To this end, the inner wall of the absorption case 142 can be coated with a material having a light absorbing property. In the case of FIG. 3, the absorption case 142 and the bottom portion 176 of the housing 170 are illustrated as being distinct, but the embodiment is not limited in this respect. That is, as in the particle sensing device 100D described later, the bottom portion 176 of the housing 170 and the absorption case 142 may be integrated. That is, the bottom portion 176 of the housing 170 can also serve as the absorption case 142.

In addition, the protruding portion 144 may have a shape protruding from the bottom surface of the absorption case 142 toward the light inlet OPL. Further, the width of the protrusion 144 may become narrower from the bottom surface of the absorption case 142 toward the light inlet OPL. For example, as illustrated in FIG. 3, projections 144 may have a circular cross-sectional shape, but embodiments are not limited in this respect. When the protrusion 144 is disposed, the main light incident on the light entrance OPL is prevented from being reflected by the inner wall of the absorption case 142 and escaping to the light entrance OPL, The absorption of the main light incident on the light entrance OPL can be improved by reflecting the main light incident through the light entrance OPL to the inner wall of the absorption case part 142. [

Fig. 20 shows a cross-sectional view of another embodiment of the particle sensing apparatus 100 shown in Fig. 1, 100D, Fig. 21 shows a side view of the particle sensing apparatus 100D shown in Fig. 20, 20 shows an upper perspective view of the particle sensing device 100D shown in Fig. 20, Fig. 23 shows a left perspective view of the particle sensing device 100D shown in Fig. 20, Fig.

20 to 24, only the portions other than those shown in Figs. 3 to 18B will be described. Therefore, it is a matter of course that the description of FIGS. 3 to 18B can be applied to portions other than those described below and not described with reference to FIGS. 20 to 23. FIG.

In the particle sensing apparatuses 100A, 100B and 100C shown in Figs. 3, 5 and 7, the packaging form of the light source unit 112A is the SMD type, while the particle sensing apparatus 100D shown in Figs. The light source portion 112A may be a dome-shaped (or Through hole type) LED, but the embodiment is not limited thereto. For example, the diameter φ of the dome type light emitting portion 110B may be 3 mm to 5 mm, and the view angle may be 20 ° or less, but the embodiment is not limited thereto.

In addition, the operating temperature of the photodiode 134 may be between -10 ° C and 50 ° C, but the embodiment is not limited to the specific operating temperature of the photodiode 134.

The lens portion 114A of the particle sensing devices 100A, 100B, and 100C shown in Figs. 3, 5, and 7 includes only one lens, whereas the particle sensing device 100D shown in Figs. The lens portion 114B of the first lens 114B-1 may include first and second lenses 114B-1 and 114B-2. The first lens 114B-1 serves to convert the light emitted from the light source portion 112B into parallel light and the second lens 114B-2 serves to convert the parallel light emitted from the first lens 114B- And can condense light to the first opening OP1.

In the case of the particle sensing apparatuses 100A, 100B and 100C shown in Figs. 3, 5 and 7, the tower portion 172 of the housing 170 is different from the light emitting case 116, In the case of the particle sensing device 100D shown, the top portion 172 of the housing 170 and the light emitting case 116 are integral. That is, it can be seen that the top portion of the housing 170 serves as the light emitting case 116.

The flow path portion 120C of the particle sensing device 100D shown in FIGS. 20 to 23 may have the structure of the double nozzle DN like the flow path portion 120C shown in FIG. 7 and FIG. Therefore, the description of the flow path portion 120C shown in Figs. 20 to 23 is replaced by the description of the flow path portion 120C shown in Figs. 7 and 8.

20, the minimum width D5 of the second flow path middle portion FII2 is in the range of 1 mm to 15 mm, for example, 2 mm to 8 mm, preferably 3 mm to 5 mm, for example, 4 mm But the embodiment is not limited thereto.

25 is an enlarged cross-sectional view of a portion 'C' shown in FIG.

25, the light receiving incidence portion 190 may include a light guiding portion 192, a cover transparent portion 194, and a light blocking portion 196. [

The light guide portion 192 may be disposed between the scattering portion SS and the light receiving portion 130B to define a third opening OP3. Here, the characteristic of the third opening OP3 may be the same as the characteristic of the third opening OP3 described above with reference to Fig. That is, the third opening OP3 is formed in such a manner that 20% to 80% of the total amount of light scattered by the particles P in the scattering section SS is an area suitable for entering the light receiving section 130B Direction and a width in the y-axis direction). In the light scattered by the particles P, the predetermined angle? From the center of the scattering portion SS to the fifth opening OP5 with respect to the optical axis LX is 24 ° to 60 ° The third opening OP3 may have an area such that the light in the range of 60 DEG is suitable for being incident on the light receiving portion 130B. As described above, it is understood that the amount of light incident on the light-receiving portion 130B can be adjusted by adjusting the area of the third opening OP3.

The area of the third opening OP3 may be different from the area of the first opening OP1. For example, the area of the first opening OP1 may be larger than the area of the third opening OP3. In this case, the focal point of the light emitted from the light emitting portion 110B is formed to be farther from the center of the scattering portion SS, so that a measurement error due to the main beam can be reduced.

The light blocking portion 196 may be disposed between the scattering portion SS and the light guide portion 192 to define a sixth opening OP6. It is possible to prevent the main light from being incident on the photodiode 134 by adjusting the width W5 of the sixth opening OP6 or to adjust the amount of the main light incident on the light receiving portion 130B and proceeding to the light absorbing portion 140 .

The width W5 of the sixth opening OP6 may be, for example, 1 mm to 15 mm, for example, 2 mm to 8 mm, preferably 3 mm to 4 mm, for example 3.5 mm, Do not.

By disposing the light intercepting portion 196 as described above, the main light can be prevented from proceeding to the photodiode 134 of the light sensing portion 134 through the fifth opening OP5. Here, the light sensing unit 134 may be implemented in a module form.

Further, the cover transparent portion 194 may be disposed between the third opening OP3 and the sixth opening OP6. The cover transparent portion 194 serves to prevent foreign matter from entering the light receiving portion 130B. The arrangement of the cover transparent portion 194 prevents the particles P passing through the scattering portion SS from penetrating into the light receiving portion 130B so that the flow of the particles P in the flow path portion 120C can be smooth And the measurement error can be reduced. In this case, even if the photodiodes 134-2 and 134-21 to 134-24 are formed on either the first surface 132-1 or the second surface 132-2 of the light transmitting member 132, The damage of the photodiodes 134-2 and 134-21 to 134-24 can also be prevented.

26 is an enlarged cross-sectional view of the portion 'D' shown in FIG.

The light sensing part 134 and the light guide part 136B shown in Fig. 26 may be disposed around the optical axis of the light transmitting member 132. [ The light sensing part 132 and the light guide part 136B may be disposed on mutually opposing surfaces of the light transmitting member 132. [ 26, the light sensing portion 134 is disposed on the second surface 132-2 of the light transmitting member 132, and the light guide portion 136B is disposed on the second surface 132-2 of the light transmitting member 132 And may be disposed on the first surface 132-1. 26, the light sensing portion 134 is disposed on the first surface 132-1 of the light transmissive member 132 and the light guiding portion 136B is disposed on the second surface 132-1 of the light transmissive member 132, May be disposed on the surface 132-2. Here, the first surface 132-1 and the second surface 132-2 are as defined in the above description of FIG. The light sensing portion 134 is disposed on the second surface 132-2 of the light transmissive member 132 and the light guiding portion 136B is disposed on the first surface 132-1 of the light transmissive member 132 The following explanation can be applied to the case of the reverse.

Except that the structures of the inner side walls 136-1 and 136-2 are different, the cross section shown in Fig. 26 is the same as the cross section shown in Fig. Therefore, the same reference numerals are used for the same parts as those shown in Fig. 9, and a brief explanation will be given below.

The scattered light having passed through the third opening OP3 proceeds to the fifth opening OP5 and the main light passing through the sixth opening OP6 passes through the fourth opening Lt; RTI ID = 0.0 &gt; (OP4). &Lt; / RTI &gt; For example, the height H2 may be from 1 mm to 15 mm, for example from 2 mm to 10 mm, preferably from 3 mm to 6 mm, e.g., 5 mm, although the embodiment is not limited in this respect.

Each of the inner side walls 136-1 and 136-2 extends from the inner side 136-11 and 136-21 defining the fourth opening OP4 and the inner side 136-11 and 136-21, -3, 136-4, and a lateral portion 136-12, 136-22 defining a fifth opening OP5. The diameter of the fourth opening OP4 having a circular planar shape should be larger than the focusing size of the main beam. If the diameter of the fourth opening OP4 is smaller than 1 mm, the entire main beam can not pass through the fourth opening OP4 and is incident on the photodiodes 134-2 and 134-21 to 134-24, Scattered light may not be sensed in the diodes 134-2 and 134-21 to 134-24. Further, when the diameter of the fourth opening OP4 is larger than 8 mm, it may be difficult to realize the slit. Thus, the diameter of the fourth opening OP4 may be from 1 mm to 8 mm, for example from 1 mm to 5 mm, preferably from 1 mm to 3 mm, for example, 2 mm, although embodiments are not limited in this respect .

The width W4 of the fifth opening OP5 may be larger than the width W6 of the outer side portions 136-12 and 126-22. The width W6 of the outer portions 136-12 and 126-22 may be 0.1 mm to 5 mm, for example, 0.4 mm to 2 mm, preferably 0.6 mm to 1 mm, for example, 1 mm, Is not limited to this. For example, when the width W4 of the fifth opening OP5 is 1.1 mm, the width W6 of the outer portions 136-12, 136-22 may be 0.8 mm, but the embodiment is not limited thereto .

The outer side portions 136-12 and 136-22 and the inner side portions 136-11 and 136-21 of the inner side walls 136-1 and 136-2 may be integrally formed.

It is preferable that at least one of the outer side portions 136-12 and 136-22 or the inner side portions 136-11 and 136-21 from the first surface 132-1 to the third opening portion OP3 of the transparent substrate 132 The cross-sectional width can be reduced. That is, the distinction between the inner portions 136-11 and 136-21 and the outer portions 136-12 and 136-22 is such that the scattered light is incident on the photodiode 134 at an angle, Lt; / RTI &gt;

The area of the fourth opening OP4 shown in Fig. 26 (for example, the area in the x-axis and the y-axis direction) is larger than the area of the sixth opening OP6 shown in Fig. 25 And the area in the y-axis direction), but the embodiment is not limited to this. As described above, when the area of the sixth opening OP6 is made larger than the area of the fourth opening OP4, the progress of the main beam to the photodiode 134-2 can be further blocked.

On the other hand, the scattering section SS can contact the plurality of openings. That is, the scattering portion SS communicates with the light emitting portion 110A through the first opening OP1, and the first flow path middle portion FII1 (or the second flow path middle portion FII2) and the second opening portion OP2 and communicates with the light receiving portions 130A, 130B through the third opening OP3 or the sixth opening OP6.

Referring to FIG. 1, the signal processing unit 150 may process an electrical signal input from the light receiving unit 130, and output the processed signal to the information analysis unit 160. In some cases, the signal processing unit 150 may be omitted, and the light receiving unit 130 may serve as the signal processing unit 150. In this case, the electrical signal output from the light receiving unit 130 may be provided to the information analysis unit 160.

The information analyzing unit 160 may use at least one of the number, density, size, or shape of the particles P by using the electrical signal provided from the signal processing unit 150 (or the light receiving unit 130 when the signal processing unit 150 is omitted) One can analyze.

Hereinafter, the measurement of the concentration of particles performed in the particle sensing apparatus 100 shown in FIG. 1 will be described with reference to the accompanying drawings.

27 is a view showing a part of the particle sensing apparatus 100 shown in Fig.

The lens portion 114, the light emitting case 116, the flow path portion 120, the light receiving portion 130, and the bottom portion 176 of the housing 170 shown in FIG. 27 correspond to the lens portion 114, The light emitting case 116, the flow path portion 120, the light receiving portion 130, and the bottom portion 176 of the housing 170, respectively, and the same reference numerals are used, and redundant description will be omitted. The first opening OP1, the scattering part SS, the third opening part OP3, the light transmitting member 132, and the light sensing part 134 shown in Fig. 27 are similar to those shown in Figs. 3 to 9, The same reference numerals are used for the first opening OP1, the scattering portion SS, the third opening OP3, the light transmitting member 132, and the light sensing portion 134 shown in FIG. 21, .

Referring to FIG. 27, the particle sensing apparatus 100 according to the embodiment may be configured such that the particles P contained in the air flowing into the flow path portion 120 are scattered by the light emitted from the scattering portion SS from the lens portion 114 L). &Lt; / RTI &gt; This is to obtain an electrical signal (i.e., one pulse) for one particle P at any one time in time. The width W7 in the first direction (e.g., the y-axis direction) in which the air of the light irradiated to the scattering part SS out of the light L indicated by the shade emitted from the lens part 114 flows, Or the height (or diameter) D6 of the scattering portion SS can be determined as follows.

For example, when the width W7 in the first direction (e.g., the y-axis direction) of the light L irradiated by the scattering section SS is larger than 6 mm, The probability that a plurality of particles P enter the region of the light L represented by shading can be increased. When the width W7 of the light L in the first direction is smaller than 2 mm, light may not be scattered in the particles P when the flow velocity of the particles P is fast. The flow rate of the particles P may be between 1 and 10 전 as described above, but the embodiment is not limited to a specific flow rate. For example, the width W7 may be from 2 mm to 6 mm, for example from 2 mm to 4 mm, although the embodiment is not limited in this respect. The shape of the lens portion 114 or the size of the first opening OP1 (that is, the area in the x-axis and the y-axis direction) is preferably in the range of 2 mm to 6 mm in the first direction, But the embodiment is not limited thereto.

The minimum height D6 of the scattering section SS in the second direction (e.g., the z-axis direction) parallel to the optical axis from the light emitting section 110 to the light receiving section 130 corresponds to the first The width W7 in the direction indicated by the arrow A in Fig. If the flow path portion 120 has a circular cross-sectional shape, the minimum diameter D6 of the scattering portion SS may be smaller than the width W7 in the first direction. The minimum height (or diameter) D6 of the scattering section SS may be 1 mm to 2 mm, for example 2 mm, but the embodiment is not limited to this.

27, the distance D7 in the direction of the optical axis from the lens portion 114 to the flow path portion 120 may be 1 mm to 4 mm. The distance D8 in the optical axis direction from the flow path portion 120 to the upper surface of the light transmitting member 132 may be 1 mm to 4 mm.

As described above, when the width W7 and the height (or diameter) D6 are determined, light is scattered by one particle in the scattering section SS, so that one electrical signal per particle (i.e., a pulse) And it is possible to accurately measure the concentration of the particles P in the information analyzer 160 by using an electrical signal at a later time. In addition, when at least one of the height (or diameter) D6 or the width W7 of the flow path portion 120 is determined as described above, two particles in the direction parallel to the optical axis (for example, in the z- It is possible to reduce the probability that the scattered light P passes through the scattering unit SS. If the two particles P overlap each other and pass the scattering unit SS, the pulse shape of the electric signal of the light incident on the light receiving unit 130 may be a bimodal shape in which two pulses are superimposed. When using an electrical signal having such a deformed shape, the concentration of the particles can not be accurately measured. However, according to the embodiment, at least one of the height (or the diameter) D6 or the width W7 of the flow path portion 120 is determined as described above, so that one pulse for one particle is received by the light receiving portion 130, So that the concentration of the particles can be accurately measured by the information analyzing unit 160. FIG. In addition, even when the pulses overlap, the concentration of the particles can be accurately measured by separating them. This will be described in more detail below.

It is also preferable that the particles P contained in the air flowing through the flow path portion 120 pass through a certain position x1, y1, z1 or a certain space? X,? Y,? Z in the scattering portion SS. This is because the intensity of the electrical signal of the light incident on the light receiving unit 130 increases as the size of the particle increases. Even if the particles have the same size, the particle is positioned at a certain point in the space within the scattering unit SS, The intensity of the electrical signal of the light incident on the light receiving unit 130 may vary. For example, when the first and second particles of the same size sequentially pass through the scattering unit SS, the position where the first particle passes through the scattering unit SS is smaller than the position where the second particle passes through the scattering unit SS. 1 opening OP1, the intensity of the electrical signal of the light scattered by the first particle may be greater than the intensity of the electrical signal of the light scattered by the second particle.

The width W7 of the light L in the first direction is smaller than the width W2 at the first position y2 at a point where the particles P pass through the scattering portion SS (for example, z1 or? Z / 2) And the second position y3.

28A and 28B are graphs showing the intensities of light L incident on the scattering unit SS, wherein the vertical axis represents the intensity of light and the horizontal axis represents the position in the y direction. Here, y2 and y3 correspond to the points shown in Fig. 27 in which the width W7 of the light L is measured.

Generally, the intensity distribution of the light L emitted from the lens section 114 and irradiated to the scattering section SS has a Gaussian distribution as shown in FIG. 28A. In this case, the start point and the end point of the electrical signal of the light scattered by the particles P may become non-uniform. In order to prevent this, the intensity of the light L incident on the scattering unit SS may have a constant square shape as shown in FIG. 28B. As described above, when the intensity of the light irradiated to the scattering unit SS is constant in the first direction, the start and end points of the electrical signal of the light scattered by the unit particles can be corrected. For example, if the start and end points of an electrical signal are determined to be valley-to-valley between pulses, as shown in Fig. 35 to be described later, the time point of the electric signal of light scattered by the particle P1 And the end point can be determined.

According to one embodiment, the lens portion 114 may be embodied as a plurality of aspherical lenses, but the embodiments are not limited thereto, so that the light intensity has a square shape as in Fig. 28B.

29A and 29B are graphs showing the state of the particles P passing through the light scattering unit SS at the first speed and the electric signals of the light scattered by the particles at the first speed 30 (a) and 30 (b) show the state of the particles P passing through the scattering section SS at a second velocity of the light L and the electrical signals of the light scattered by the particles Respectively.

When the second velocity of the particle shown in Fig. 30 (a) is larger than the first velocity of the particles shown in Fig. 29 (a), the width T1 of the electric signal shown in Fig. the width T2 of the electrical signal shown in (b) becomes shorter. For example, the width (T1 or T2) may be 0.4 ms to 4 ms. Thus, the width of the electrical signal of the light scattered by the particle P varies according to the speed at which the particle P passes through the scattering portion SS. Considering this, when one particle (P) does not go straight in the scattering part (SS) and physically spreads or diagonally travels, the width of the electrical signal of the light scattered by the particles can accurately reflect the flow rate of the particles I will not. That is, when there are two first and second particles passing through the scattering unit SS at the same speed, it is assumed that the first particle does not proceed diagonally but goes straight and the second particle proceeds diagonally. Considering the velocity expressed by the following equation (1), the first particle can pass in the shortest time in the first direction, while the second particle can pass in the first direction with a time longer than the shortest time.

Therefore, according to the embodiment, the flow path portion 120 has a structure in which the particles P can go straight on the scattering portion SS. Therefore, an electrical signal having widths T1 and T2 accurately reflecting the particle velocity can be obtained, so that the concentration of particles can be accurately measured.

As described above, the light emitted from the light emitting portion 110 and condensed by the lens portion 114 is scattered every time the particles P pass through the scattering portion SS of the flow path portion 120, The light is incident on the light receiving unit 130 and then output to the signal processing unit 150 as an electrical signal. For example, when 100 particles pass through the scattering section (SS), the electrical signal of the scattered light can have 100 pulses.

Meanwhile, the signal processing unit 150 processes the electrical signal input from the light receiving unit 130, and outputs the signal processed result to the information analysis unit 160 as a particle-specific pulse.

Hereinafter, a signal processing unit 150 shown in FIG. 1 according to an embodiment will be described with reference to the accompanying drawings.

FIG. 31 shows a block diagram of an embodiment 150A of the signal processing unit 150. FIG.

31 may include a preprocessing unit 152, a post-processing unit 154, and an analog-to-digital converter (ADC) 156. The signal processing unit 150A shown in FIG.

The preprocessing unit 152 converts the electric signal of the current type supplied from the light receiving unit 130 through the input terminal IN2 into a voltage form, filters the high-frequency components of the converted result, and amplifies the filtered result first do.

The post-processing unit 154 filters the high-frequency components of the signal output from the preprocessing unit 152, secondarily amplifies the filtered result, and outputs the amplified result to the ADC 156 as a particle-specific pulse.

The ADC 156 converts the analog pulses of the particle output from the post-processor 154 into digital form and outputs the converted result to the information analyzer 160 via the output terminal OUT3. Optionally, the ADC 156 may be omitted. In the case of using digital type particle pulses rather than the analog type, the information analyzing unit 160 can more easily perform an operation for analyzing information. For example, each pulse can be sampled at 20 or more in the analog type particle-by-particle pulse output from the post-processor 154, but the embodiment is not limited to a specific number of samples. Also, the sampling rate of the ADC 156 may be greater than or equal to 50 ksps, but the embodiment is not limited to the specific sampling rate of the ADC 156. The sampling of 50,000 times per second corresponds to 0.02 ms divided by 20 ms in terms of a period. This is related to that the minimum value of the pulse widths T1 and T2 shown in Figs. 29 (b) and 30 (b) is 0.4 ms.

32 shows a circuit diagram according to one embodiment of the preprocessing section 152 and the post-processing section 154 shown in Fig. 31. Fig. 33 shows a circuit diagram of the preprocessing section 152 and post-processing section 154 shown in Fig. (V1, V2, V3, V4) at the point.

In Fig. 33, the horizontal axis represents frequency and the vertical axis represents gain.

32, the preprocessing unit 152 includes a current / voltage conversion unit 152A, a first high pass filter (HPF) 152B, a resistor R3, a first operational amplifier OP1, And a first low pass filter (LPF) 152C.

The current / voltage converter 152A converts the electric signal of the current form output from the light receiver 130 into a voltage form, and outputs the converted voltage form signal V1. To this end, the current / voltage conversion unit 152A may include a first resistor R1. The first resistor R1 is connected between the light receiving portion 130 and the reference potential.

The first high-pass filter 152B filters the high-frequency component of the voltage-converted signal V1 and outputs the filtered result V2 to the non-inverting input terminal of the first operational amplifier OP1. To this end, the first high-pass filter 152B may include a second resistor R2 and a first capacitor C1. The second resistor R2 is disposed between the non-inverting input terminal of the DMS first operational amplifier OP1 and the reference potential and the first capacitor C1 is connected between the output V1 of the current / Inverting input terminals of the operational amplifier OP1. For example, the first high-pass filter 152B can reduce the gain of the DC component of the output V1 of the light-receiving unit 130 and the signal of 1 Hz or less.

The first amplification unit is connected to the first LPF 152C to amplify the output V2 of the first high-pass filter 152B and output the amplified result to the post-processing unit 154. [ To this end, the first amplifying unit may include a first operational amplifier OP1 and a resistor R3. The first operational amplifier OP1 includes a non-inverting input terminal connected to the output of the first HPF 152B, an inverting input terminal connected to the first LPF 152C, an output connected to the output of the preprocessing unit 152, Terminal.

At this time, the third resistor R3 is connected between the inverting input terminal of the first operational amplifier OP1 and the reference potential, and can perform the role of the first LPF 152C and serve as the first amplifier It is possible.

The first low pass filter 152C filters the low frequency component at the output of the first HPF 152B while amplifying the signal V2 together with the first operational amplifier OP1 and outputs the filtered result V3 to the post- (154). To this end, the first low-pass filter 152C may include a fourth resistor R4 and a second capacitor C2. The fourth resistor R4 and the second capacitor C2 may be connected in parallel to each other between the inverting input terminal and the output terminal of the first operational amplifier OP1.

The post-processing unit 154 may include a second high-pass filter 154A and a second amplification unit 154B. The second high-pass filter 154A filters the high-frequency component of the output V3 of the preprocessor 152 and outputs the filtered result to the second amplifier 154B. To this end, the second high-pass filter 154A may include a fifth resistor R5 and a third capacitor C3. The third capacitor C3 is disposed between the output V3 of the preprocessing unit 152 and the second amplifying unit 154B and the fifth resistor R5 is disposed between the second amplifying unit 154B and the reference potential. .

The second amplifying unit 154B can amplify the output of the second high pass filter 154A and output the amplified result V4 to the ADC 156. [ To this end, the second amplifying unit 154B may include a second operational amplifier OP2, sixth and seventh resistors R6 and R7. The sixth resistor R6 is connected between the inverting input terminal of the second operational amplifier OP2 and the reference potential and the seventh resistor R7 is connected between the inverting input terminal and the output terminal of the second operational amplifier OP2 .

Also, the signal processor 150 may remove various noise such as a noise of an electric signal received from the light receiving unit 130, a power noise, and the like. For example, the noise eliminator 158 shown in FIG. 32 serves to eliminate power noise. To this end, the noise canceller 158 may include fourth and fifth capacitors C4 and C5 connected in parallel. Further, the DC power supply V may be arranged for driving the first and second operational amplifiers OP1 and OP2.

The photodetector 130 may be implemented by a photodiode PD, a sixth capacitor C6, an eighth resistor R8 and a current source I connected in parallel to each other. But is not limited to configuration. The output V1 of the light receiving unit 130 is related to the performance of the optical system such as the optical trap and the lens unit 114 due to the crosstalk of the optical system and has a direct current component of 10 ㎂ and an alternating current component of 100 ㎀ But the embodiment is not limited thereto.

32, the transfer function, that is, the gain between the output V1 of the light receiving unit 130 and the output V4 of the second amplifying unit 154B may be 195 dB, but the embodiment is not limited to this. The signal processor 150 can be implemented using operational amplifiers OP1 and OP2 having a high amplification ratio and a short rise and fall time and a slew rate of 0.8 V / It is not limited.

The gain in the high-frequency region may be low in a circuit with a high-speed response, and the rise time and fall time of the pulse may be long. If a pulse with a narrow width is input to such a slow-response circuit, the amplification may start slowly and not be amplified to the desired level. Thus, if the pulse is not amplified to a desired level, the information analyzer 160 may not correctly recognize the electrical signal. For this purpose, the signal processing unit 150 includes a band-pass filter for filtering a frequency band having a constant gain determined according to the narrow pulse width, for example, a frequency band of 100 Hz to 1000 Hz. If the frequency band to be band-pass filtered is increased, even if an electrical signal having various widths is provided from the light-receiving unit 130, the electrical signal can be faithfully amplified. For band pass filtering, the signal processing unit 150 may use at least one low-pass filter and at least one high-pass filter as illustrated in FIG. 32, or may use only one band-pass filter. The signal processing unit shown in Fig. 32 is merely an example. That is, the signal processing unit 150 converts the form of the signal output from the light receiving unit 130 into a voltage, band-pass filters the desired frequency band of 100 Hz to 1000 Hz from the result of the voltage conversion, The embodiment is not limited to the specific circuit configuration of the signal processing unit 150. [

As described above, by filtering the specific frequency band of the signal in the signal processing unit 150, it is possible to amplify the signal having the narrow pulse width provided from the light receiving unit 130, and the information analyzing unit 160, which will be described later, To be analyzed accurately. Since the gain of the signal processing unit 150 is not lowered even in this case, the intensity of the pulse per particle is amplified, so that the information analyzer 160 adjusts the particle concentration So that it can be analyzed accurately.

On the other hand, the information analyzing unit 160 divides the intensity of a level received by the signal processing unit 150 into a plurality of channels, calculates the flow rate of the air, the density of the particles, And the particle size can be used to obtain the concentration of the particles as shown in the following equation (2), and the concentration of the particles can be output through the output terminal OUT2.

Here, PM denotes the concentration of the particles, i denotes the channel number, n denotes a positive integer of 2 or more as the total number of channels, NPi denotes the number of particles having a size belonging to the i-th channel, Vi denotes Ρ is the density of the particles in units of ig / m 3, F is the flow rate of air in units of ㎥ / s, and ri is the i-th channel Represents a particle size (for example, a representative value of the particle size). At this time, the density (rho) of the particles is a fixed value, for example, 1.15 g / cm3 can be substituted.

34A and 34B are graphs showing examples of pulses per particle provided from the signal processor 150 to the information analyzer 160. The horizontal axis indicates time and the vertical axis indicates signal levels of pulses per particle.

The particle-specific pulses supplied from the signal processing unit 150 to the information analysis unit 160 may be in a sinusoidal form, as illustrated in FIG. 34A, or in a square wave form, as shown in FIG. 34B . 34A, when the electrical signal output from the light receiving unit 130 is a sinusoidal curve, the pulse shape of the particle output from the signal processing unit 150 is a sinusoidal shape as shown in FIG. If the electrical signal is in the form of a square wave, it may have a square wave form as shown in FIG. 34B.

34A and 34B are one example for helping understanding of the operation of the information analyzing unit 160. The embodiment is not limited to the type of the signal output from the signal processing unit 150. [

FIG. 35 is a graph showing an enlarged view of a part of the waveform shown in FIG. 34A.

The particle-specific pulses output from the signal processing unit 150 have pulses as many as the number of particles having passed through the scattering unit SS. For example, FIG. 35 is an example of a particle-by-particle pulse having five pulses generated when five particles P1, P2, P3, P4, and P5 are scattered by light at the scattering portion SS. As described above, the particle-by-particle pulses have a continuous form of a plurality of pulses.

Referring to FIG. 35, the larger the particle size, the greater the intensity of the pulse of each particle. For example, since the size of the particle P1 is larger than that of the particle P5, the intensity of the electric signal of the light scattered by the first particle P1 is smaller than that of the electric charge of the light scattered by the fifth particle P5 Is greater than the intensity of the signal.

Hereinafter, an embodiment of the information analysis unit 160 shown in FIG. 1 will be described with reference to the accompanying drawings.

FIG. 36 is a block diagram of an information analyzer 160 according to an embodiment 160A. FIG. 37 is a flowchart for explaining a particle concentration calculation method performed by the information analyzer 160. FIG.

Hereinafter, the particle concentration calculation method shown in FIG. 37 is described as being performed in the information analysis unit 160A shown in FIG. 36, but the embodiment is not limited to this. That is, it is needless to say that the particle concentration calculation method shown in FIG. 37 can also be performed by the information analysis unit 160 having a configuration other than that of FIG.

The information analyzing unit 160A shown in FIG. 36 is described as performing the particle concentration calculating method shown in FIG. 37, but the embodiment is not limited to this. That is, it goes without saying that the information analyzing unit 160A shown in FIG. 36 can perform the particle concentration calculating method in other steps than those shown in FIG.

The information analysis unit 160A shown in FIG. 36 may include a channel classification unit 161, a particle size determination unit 163, a counting unit 165, a flow rate calculation unit 167, and a concentration calculation unit 169 have.

In operation 210, the channel classifying unit 161 classifies the levels of the pulses output from the signal processor 150 into the first through n-th channels.

To facilitate understanding of the embodiment, the following Table 1 will be described with reference to Figs. 36 and 37 as an example, but the embodiment is not limited to this.

I (V) d (탆) r (탆) i r (ch _i ) (탆) Number (# / s) ri (占 퐉) 0.1 to 1.0 0.3 to 0.5 0.15 to 1.0 One 0.15 NP _0.3 0.19 1.0 to 2.0 0.5 to 1.0 0.1 to 1.0 2 0.25 NP _0.5 0.35 2.0 to 2.5 1.0 to 2.5 0.1 to 1.0 3 0.5 NP _1.0 0.79 2.5 to 5 2.5 to 10 0.1 to 1.0 4 1.25 NP _2.5 2.5

In Table 1, I represents the intensity of a level that the particle-specific pulses output from the signal processing unit 150 can have, d represents the diameter of the particle, r represents the radius of the particle, i represents the channel number , r (ch _i ) denotes a predetermined particle size for the i-th channel, and r _i is a geometric mean value as a representative value of the radius of the particle. Further, in Table 1, the diameter d or the radius r of the particle according to the level intensity I of the particle-specific pulse can be experimentally determined in advance.

For example, suppose that the intensity of the level of pulses shown in Fig. 34A or Fig. 34B provided to the information analysis unit 160 from the signal processing unit 150 may be 0.1 volts (V) to 5 volts , The channel dividing unit 161 allocates a level of 0.1 volt to 1.0 volt to a first channel, assigns a level of 1.0 volts to 2.0 volts to a second channel, and a level of 2.0 volts to 2.5 volts To the third channel, and assigns a level of 2.5 volts to 5 volts to the fourth channel. In this manner, the channel dividing unit 161 divides 0.1 volts to 5 volts into four first through fourth channels (Step 210). For example, the channel classifying unit 161 may perform step 210 using the per-particle pulses supplied from the signal processor 150 through the input terminal IN3, but the present invention is not limited thereto. That is, according to another embodiment, without the aid of the particle-specific pulses provided through the input terminal IN3, the channel classifying unit 161 predicts the intensity of the level of each particle-specific pulse experimentally in advance and performs step 210 You may. That is, in order to perform operation 210, the channel classifying unit 161 may store data corresponding to Table 1 in advance.

After operation 210, the particle size determination unit 163 determines the particle size corresponding to each pulse of the particle-specific pulse that is output from the signal processor 150 and provided through the input terminal IN3 (operation 220). For example, when the particle-specific pulse shown in Fig. 35 is input through the input terminal IN3, the particle-size determining unit 163 determines the particle size of the particles (P1, P2, P3, P4, P1, P2, P3, P4, P5). For example, the particle size determination unit 163 can determine the size of each of the particles (P1, P2, P3, P4, and P5) using the level of each pulse per particle. According to one embodiment, the particle size determination unit 163 can determine the particle size using the following function.

r? f (PA)

Here, PA represents the maximum intensity of each pulse in the particle-specific pulse, and r represents the size of the particle corresponding to each pulse in the particle-specific pulse. This function can be an n-order linear fitting equation or a logarithmic function.

For example, suppose that the maximum intensity of the pulse of light scattered in the particle P1 in the particle-by-particle pulse shown in Fig. 35 is 1.2 volts. At this time, referring to Table 1, when the level I is 1.2 volts, the diameter r of the particles P1 in the second channel is 0.3 mu m. In other words,

0.3? F (1.2)

.

After step 220, the counting unit 165 counts the number of particles NB _{i per a} plurality of channels by using the particle size r corresponding to each pulse in the particle pulses determined by the particle size determination unit 163, (Step 230). According to one embodiment, the counting unit 165 may count the number of particles per a plurality of channels as follows.

r? r (chi) <r <r (chi + 1)

Where r represents the size of the particle determined in operation 220 using the function f (PA), r (chi + 1) represents the size of the particle determined in advance for the i + 1 channel, r chi) represents a predetermined particle size for the i-th channel.

For example, when the size r of the particles P1 is determined to be 0.3 占 퐉 in step 220, 0.3 占 퐉 of r is larger than 0.15 of r (ch1) and smaller than 0.5 of r (ch3) So that the number of particles (NB ₂ ) is counted up. At this time, ri is 0.35 mu m which is the representative value r2 of the second channel ch2.

After performing steps 210 to 230 for all the pulses included in the particle-specific pulses supplied from the signal processing unit 150 to the information analysis unit 160, the flow rate calculation unit 167 calculates the flow rate of the particles The flow rate F of the air is calculated using the pulse (operation 240). For example, the flow rate calculator 167 can calculate the flow rate of air using the width T of a pulse belonging to an arbitrary channel among n channels, as shown in the following equation (3).

Here, a and b represent pre-determined variables.

As an example, a method of obtaining a and b in advance will be briefly described as follows.

The concentration of the particles is measured through a particle concentration meter, the concentration of the measured particles is substituted into the PM equation of the following formula (4), and the inversion , A and b can be obtained.

In this case, a and b can be obtained by plotting a graph obtained by substituting a measured PM value into the y-axis and a and b with the PM equation of Equation (4) as the x axis.

The width of the pulse belonging to any of the channels described above may be plural. At this time, according to the embodiment, it is possible to determine an average value or an intermediate value of a plurality of pulse widths belonging to an arbitrary channel as a width T to be substituted into the equation (3).

Further, the width T of the pulse to be substituted into the equation (4) can be calculated (or determined) in various ways. For example, the width T can be calculated by a full width half maximum (FWHM) or a Lorentzian curve fitting method of a pulse. In particular, a pulse having a bimodal shape may be input through the input terminal IN3. This is a result that light is scattered by a plurality of particles entering the scattering unit SS and a plurality of pulses are overlapped as described above. When a plurality of pulses are overlapped in this way, they may affect each other's waveform, and it may be difficult to accurately know the strength or width of the level of the pulse. Therefore, according to the embodiment, since the intensity and the width of the pulse level can be measured accurately by separating a plurality of waveforms, the concentration of the particles can be accurately derived. For example, a plurality of waveforms can be separated by the Lorenz-type curve fitting method, but the embodiments are not limited thereto.

According to the embodiment, an arbitrary channel includes a first channel (ch ₁ ) corresponding to the smallest level intensity that the particle-specific pulse can have, and an n-th channel (ch _n ) 2 to an (n-1) _th channel (ch ₂ to ch _{n -1} ). This is because, if the first channel (ch ₁ ) or the last channel (ch _n ) is selected, the accuracy of the flow rate F may be lowered.

After step 240, the concentration calculator 169 calculates the number of particles (NB ₁ to NB _n ) counted by the counting unit 165, the number of particles allocated to each of the plurality of channels stored in the channel separator 161 The concentration PM of the particles is calculated by substituting the representative value ri, the density p of the previously stored particles and the flow rate F calculated by the flow rate calculation unit 167 into the equation 2 described above, And the concentration PM of the particles is output through the output terminal OUT2 (operation 250).

Referring again to FIG. 1, the power supply unit 152 serves to supply power to the light source unit 112 and the fan 180 under the control of the information analysis unit 160. According to the embodiment, the particle sensing apparatus 100 may selectively amplify only an input signal corresponding to a constant incident light frequency. For this, a Lock-In-Amp method can be used. That is, the information analysis unit 160 may control the power supply unit 152 to turn on the light source unit 112 of the light emitting unit 110 at a predetermined frequency to modulate the light emitted from the light emitting unit 112.

The communication unit 154 can communicate with the outside and exchange information under the control of the information analysis unit 160. [ For example, the concentration of the particles calculated by the information analysis unit 160 may be output through the output terminal OUT2 or may be transmitted to the outside through the communication unit 154. [ The data stored in the channel classifying unit 161 as shown in Table 1 may need to be changed depending on the environment in which the particle sensing apparatus 100 is used. At this time, the information analysis unit 160 may receive the data of Table 1 from the outside through the communication unit 154, and may store the received data in the channel classification unit 161. In addition, the communication unit 154 may interface with the information analysis unit 160 to the outside.

The particle sensing apparatuses 100, 100A to 100D according to the above-described embodiments have the following effects.

In general, the particle sensing apparatus measures the concentration (PM ') of a particle using the following equation (5).

Here, F 'is an air flow rate, and can be expressed by the following equation (6).

In Equation (6), the flow rate is a fixed value. Therefore, when the flow rate around a general particle sensing apparatus changes, the concentration of the particles measured by the particle sensing apparatus can not be corrected.

On the other hand, the particle sensing apparatus 100 according to the embodiment corrects the change of the flow velocity by the calculation formula (2) by indirectly measuring and estimating the flow velocity of the equation (6) The concentration of the particles can be measured accurately without the aid of the above-mentioned method. That is, since the particle sensing apparatus 100 receives a small influence of the surrounding wind, it can accurately measure the concentration of the particles in any fluid within a certain range.

The particle sensing apparatus 100 further includes a fan 180 to induce a flow of air such that the air flowing into the flow path inlet FI flows to the flow path outlet FO via the scattering unit SS . Therefore, many particles P contained in the air can flow into the flow path portion 120 and can be sensed, so that the sensing ability of the particles P can be improved. This fan 180 may be needed to calculate the concentration of the particles in the same way as in equations (5) and (6).

However, the particle sensing apparatus 100 according to the embodiment can accurately calculate the concentration of particles without the aid of a heater (not shown) or the fan 180. Thus, the particle sensing apparatus 100 according to the embodiment does not require the fan 180. Therefore, it can be manufactured at a low cost because of the embodiment, so that it is possible to obtain price competitiveness, noise generated by the fan 180 is not generated, measurement accuracy of the particle concentration is deteriorated due to aging of the fan 180, So that long term reliability can be obtained and no electric noise due to the driving of the fan 180 is generated. In addition, the degree of freedom of installation of the particle sensing apparatus 100 according to the embodiment which is not affected by the flow velocity can be improved.

The particle sensing apparatus according to the above embodiments can be applied to home and industrial air cleaners, air purifiers, air cleaners, air coolers, air conditioners, air quality management systems for buildings, It can be applied to an air conditioning system or an indoor air quality measurement apparatus for a vehicle. However, it is needless to say that the particle sensing apparatuses 100, 100A to 100D according to the embodiments are not limited to these examples and can be applied to various fields.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that various modifications and applications are possible. For example, each component specifically shown in the embodiments can be modified and implemented. It is to be understood that all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

100, 100A to 100D: particle sensing devices 110, 110A, 110B:
120, 120A, 120B, 120C: a flow path portion 130, 130A, 130B:
140: light absorbing part 150: signal processing part
152: power supply unit 154:
160: information analysis unit 170: housing

Claims (12)

A light emitting portion for emitting light;
A flow path disposed below the light emitting part in a first direction intersecting the optical axis of the light emitting part and through which air including particles flows;
A light receiving portion disposed on the optical axis below the flow path portion and adapted to inject scattered light for each particle flowing in the flow path portion;
A signal processing unit for receiving and processing an electric signal of light emitted by the particle from the light receiving unit and outputting the signal processed result as a particle-specific pulse; And
Wherein the intensity of the level that the particle-specific pulse can have is divided into a plurality of channels, and the concentration of the particles is determined by using the flow rate of the air, the density of the particles, And an information analyzing section for acquiring the information.

(Where PM denotes the concentration of the particles, i denotes a channel number, n denotes a total number of channels, a positive integer of 2 or more, NP _i denotes the number of particles belonging to the i-th channel , V _i represents the volume of the particle, p represents the density of the particle, F represents the flow rate of the air, and r _i represents the size of the particle belonging to the i-th channel. The apparatus according to claim 1, further comprising a power supply unit for supplying power to the light emitting unit under the control of the information analysis unit,
Wherein the information analyzing unit controls the power supply unit to turn on the light emitting unit at a predetermined frequency to modulate light emitted from the light emitting unit. 2. The apparatus of claim 1, wherein the signal processing unit
A preprocessing unit for converting the electrical signal of the current type received from the light receiving unit into a voltage form, filtering the high-frequency components of the converted result, and firstly amplifying the filtered high-frequency components; And
And a post-processing unit for filtering the high-frequency components of the signal output from the preprocessing unit and then amplifying the high-frequency components of the signal by a second order and outputting the amplified signal as the particle-by-particle pulse. 4. The apparatus of claim 3, wherein the pre-
A current / voltage converting unit for converting an electric signal of a current type outputted from the light receiving unit into a voltage form;
A first high pass filter for filtering high frequency components of the signal converted into the voltage form; And
And a first amplifier for amplifying the output of the first high pass filter. 5. The apparatus of claim 4, wherein the post-processing unit
A second high pass filter for filtering the high frequency component of the result amplified by the first amplifier; And
And a second amplifier for amplifying an output of the second high-pass filter. 2. The apparatus of claim 1, wherein the signal processing unit
And an analog-to-digital converter for converting an analog type particle-by-particle pulse into a digital form and outputting it to the information analysis unit. The apparatus of claim 1, wherein the information analysis unit
A channel classifying unit for classifying intensity levels of the particles-specific pulses output from the signal processing unit into first through n-th channels;
A particle size determination unit that determines a size of the particle corresponding to each pulse in the particle-specific pulse output from the signal processing unit;
A counting unit for counting the number of particles for each of a plurality of channels by using the size of the particles corresponding to each pulse in the particle-by-particle pulses determined by the particle size determining unit;
A flow rate calculation unit for calculating a flow rate of the air; And
Calculating a concentration of the particles by using the number of the counted particles, a representative value (r _i ) of the particle size assigned to each of the plurality of channels, a density (?) Of the particles, And a calculation unit. 8. The particle sensing apparatus of claim 7, wherein the particle size determining unit determines the size of the particle using a function as described below.
r? f (PA)
(Where PA represents the maximum intensity of each pulse in the particle-specific pulse and r represents the size of the particle corresponding to each pulse in the particle-by-particle pulse). 9. The particle sensing apparatus of claim 8, wherein the function is an n-th order linear fitting equation or a logarithmic function. 9. The particle sensing apparatus of claim 8, wherein the counting unit counts the number of particles per a plurality of channels as follows.
r _i? r (ch _i ) <r <r (ch _{i + 1} )
Wherein r represents the size of the particle determined using the function, r (ch _{i + 1} ) represents a predetermined particle size for the i + 1 th channel, and r (ch _i ) Indicates the size of the particle determined beforehand for the channel.) The apparatus according to claim 7, wherein the flow rate calculator
wherein a width of the pulse belonging to an arbitrary channel among the n channels is used to obtain the flow rate of the air as follows.

(Where T represents the width of the pulse corresponding to the arbitrary channel, and a and b represent pre-determined variables). 12. The method of claim 11, wherein the arbitrary channel is a second to an n-th channel except for a first channel corresponding to a lowest level intensity that the per- One of the channels is a particle sensing device.

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