KR20230037866A - Testing device and method of detectability of colloidal crystal-based colorimetric sensor - Google Patents

Abstract

The present invention relates to a device and a method configured to enable a photonic crystal-based gas detection sensor to be positioned in a chamber and inspect a detection ability of the sensor while allowing a gaseous substance to be detected to flow inside the chamber. The present invention provides the device and the method for inspecting the detection ability of the sensor by exposing the photonic crystal-based sensor to gaseous VOCs.

Description

Testing device and method of detectability of colloidal crystal-based colorimetric sensor}

It relates to an apparatus and method for testing the detection ability of a sensor for detecting a gaseous substance by photonic crystal-based color change.

Mass spectrometry or gas chromatography has conventionally been used to detect harmful substances emitted in gaseous form, such as volatile organic compounds (VOCs). This conventional detection method takes time for measurement and requires expensive and large equipment, so there is a problem in that gaseous harmful substances cannot be easily detected in real time.

Accordingly, as sensors capable of rapidly measuring VOCs, metal-organic frameworks-based sensors, quartz crystal microbalance-based sensors, and photonic crystal-based sensors have been developed.

The double photonic crystal-based color change sensor is small in size, portable, easy to manufacture, and can visually check the detection of VOCs concentration without power. A photonic crystal is also called a photonic bandgap crystal and is a crystal having a periodic structure. Light incident on a periodic array of crystals diffracts, which can be explained by Bragg's law.

Due to the periodic structure, the photonic crystal reflects only light of a specific wavelength, resulting in a structural color, and thus a photonic bandgap, a specific region through which light cannot pass. When the photonic crystal material sensor absorbs VOCs and expands, the periodic arrangement of the photonic crystal changes, so the wavelength of the reflected light changes, resulting in a shift in the photonic bandgap and a change in structural color. With this principle, a photonic crystal-based color change sensor can monitor VOCs, and the sensor's ability to detect VOCs can be evaluated by measuring a bandgap shift.

Research on a photonic crystal-based sensor for detecting VOCs gas is being conducted, but there is no protocolized method for evaluating the sensing performance by actually exposing the developed sensor to gaseous VOCs. Performance evaluation studies on conventional VOCs detection sensors measured the change in wavelength of the sensor by exposing the sensor to a VOCs solution or VOCs vapor generated from the VOCs solution. This conventional evaluation method has a problem in that it is difficult to quantitatively evaluate the sensing ability because the color of the sensor surface does not evenly change due to the non-uniform concentration of VOCs.

An object of the present invention is to provide a device and method capable of inspecting the sensing ability of a sensor by exposing a photonic crystal-based sensor to gaseous VOCs.

The present invention, a chamber configured to test the sensing ability of a photonic crystal-based color change sensor while flowing a gas to be sensed; a measuring probe electrically connected to a light source and a spectrometer and installed in the chamber to measure a color change of the sensor; a supply pipe connected to the chamber; a discharge pipe connected to the chamber; a suction pump connected to the discharge pipe; and a controller controlling the operation of the pump to adjust the flow rate of the target gas flowing in the chamber.

As an example, the measurement probe may measure an initial reflected light wavelength of the sensor stored in the chamber during an initial time during which the pump is not operated. The controller may supply the target gas to the chamber at a first gas flow rate for a first time after the initial time has elapsed, and supply the target gas to the chamber at a second gas flow rate for a second time thereafter. can control. The measuring probe may measure a reflected light wavelength of the sensor housed in the chamber during the second time period.

As an embodiment, a supply-side concentration meter coupled to the supply pipe to measure the concentration of the target gas to be detected in the supply pipe, and a discharge-side concentration meter to be coupled to the discharge pipe to measure the concentration of the target gas to be detected in the discharge pipe may further include.

As an embodiment, the first time may be a time taken until both the concentration measured by the supply-side concentration meter and the concentration measured by the exhaust gas concentration meter reach a predetermined concentration.

As an example, the flow rate of the second gas may be slower than the flow rate of the first gas.

As one embodiment, the supply pipe may further include a valve installed in the supply pipe so as to selectively communicate fluidly with a source of the target gas or an air compressor.

As an embodiment, the controller controls the valve so that the supply pipe is in fluid communication with the supply source of the gas to be detected during the first time and the second time, and the supply pipe for a third time after the second time has elapsed. The valve may be controlled so that air without a target gas to be sensed flows into the supply pipe through fluid communication with the air compressor, and operation of the pump may be stopped during the third time period.

As an embodiment, the measuring probe may measure the reflected light wavelength of the sensor housed in the chamber during the third time period.

In one embodiment, the chamber is made of a material containing aluminum and is opaque.

As an example, a sensor seating tray received in the chamber and positioning the sensor relative to the measurement probe may be further included.

In another aspect of the present invention, in a chamber in which a photonic crystal-based color change sensor is accommodated and a measuring probe electrically connected to a spectrometer and a light source is installed, measuring the wavelength of an initial reflected light of the sensor during an initial time before a gas to be detected is supplied to the chamber ; supplying a target gas to the chamber at a first gas flow rate for a first time after the initial time has elapsed; and measuring a reflected light wavelength of the sensor while supplying the target gas to the chamber at a second gas flow rate for a second time after the first time has elapsed.

As an embodiment, the first time may be a time taken until both the concentration in the supply pipe of the target gas supplied to the chamber and the concentration in the discharge pipe of the target gas discharged from the chamber reach a predetermined concentration. .

As an example, the flow rate of the second gas may be slower than the flow rate of the first gas.

As an example, the second time may be a time taken until the wavelength of the reflected light of the sensor does not change any more in a state in which the sensor is exposed to the target gas flowing at the second gas flow rate.

As an embodiment, the method further includes stopping supply of the target gas for a third time after the lapse of the second time and measuring the reflected light wavelength of the sensor while supplying air without the target gas to the chamber. can

As an example, the method may further include analyzing a bandgap shift of the sensor by comparing wavelengths of reflected light of the sensor before and after being exposed to the target gas.

As an embodiment, the step of measuring the wavelength of the initial reflection light of the sensor may include measuring the wavelength of the initial reflection light n times or more at equal time intervals, supplying the target gas to the chamber at a second gas flow rate, and measuring the wavelength of the reflected light of the sensor. In the measuring step, the reflected light wavelength of the sensor may be measured m or more times at equal time intervals during the second time period.

As an example, in the step of analyzing the bandgap shift of the sensor, the bandgap shift may be analyzed based on an average value of n initial reflected light wavelengths and an average value of m reflected light wavelengths measured for a second time.

As an example, in the step of analyzing the bandgap shift of the sensor, the bandgap shift may be analyzed by performing a weighted arithmetic average of m reflected light wavelengths measured for the second time period with an intensity as a weight.

As an example, the gas to be sensed may be a volatile organic compound (VOCs) gas, and the sensor may be a photonic crystal-based color change sensor in which an array of photonic crystals changes when exposed to the VOCs gas.

According to the present invention, since the sensing ability of the sensor can be tested in a state of being exposed to gaseous VOCs, the sensing ability can be quantitatively and accurately tested.

1 is a diagram for explaining the gas detection principle of a photonic crystal-based color change sensor. FIG. 1 (a) shows a photonic crystal arrangement inside the sensor before being exposed to VOCs gas, and FIG. It shows the photonic crystal arrangement inside the sensor after being exposed to gas, and FIG. 1(c) is a graph measuring the reflected light wavelength of the sensor before and after being exposed to VOCs gas with a spectrometer,
2 is a schematic configuration diagram of an apparatus for testing the sensing ability of a sensor according to an embodiment of the present invention;
3 is an enlarged perspective view of part A of FIG. 2;
4 is an exploded perspective view of the chamber shown in FIG. 3;
5 is a flowchart of a method for inspecting the sensing ability of a sensor according to an embodiment of the present invention;
6 is a graph obtained by measuring and analyzing the reflected light wavelength of the sensor exposed to 100 ppm of o -Xylene gas over time, and FIG. 6(b) is a graph according to the 'center spectrum method' in which intensity is applied as a weight.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to components of each drawing, it should be noted that the same components have the same numerals as much as possible even if they are displayed on different drawings. In addition, if it is determined that the subject matter of the present invention may be obscured, the detailed description thereof will be omitted. In addition, embodiments of the present invention will be described below, but the technical idea of the present invention is not limited or limited thereto and can be practiced by those skilled in the art.

The detecting ability testing apparatus and testing method according to the present invention target a photonic crystal-based colorimetric sensor. Hereinafter, VOCs gas will be illustratively described as a gas to be detected, but the present invention is not limited thereto, and when exposed to a specific gaseous material, the color changes according to a change in the photonic crystal array, and any photonic crystal base capable of measuring bandgap shift The concept of the present invention can also be applied to a color change sensor.

Fig. 1 (a) shows the periodic arrangement of particulates in the sensor 1a before being exposed to VOCs gas, and Fig. 1 (b) shows the periodic arrangement of particulates in the sensor 1b exposed to VOCs gas. shows the structure. In the photonic crystal-based color change sensor, when exposed to VOCs gas, particles inside the sensor absorb VOCs and swell, so the distance between particle layers after exposure (d ₂ ) is greater than the distance between particle layers before exposure (d ₁ ). do. Therefore, the sensor exposed to VOCs changes the diffraction angle of the incident light and shifts the wavelength of the reflected light. Figure 1 (c) is a graph measuring the intensity (intensity) according to the wavelength of reflected light with a spectrometer before (blue solid line) and after (red solid line) exposure to VOCs, showing the bandgap shift after exposure to VOCs can confirm that

The present invention relates to an apparatus and method for inspecting the detection capability of a photonic crystal-based VOCs detection sensor operating on the above-described principle in a state in which it is exposed to gaseous VOCs. Referring to FIG. 2 , an apparatus for inspecting the sensing ability of a sensor according to an embodiment of the present invention will be described in detail.

An apparatus for testing the detection ability of a sensor according to an embodiment includes a chamber 200, a supply pipe 110 connected to the chamber, a discharge pipe 120 connected to the chamber, a measuring probe 130 installed on the upper part of the chamber, and a suction pump connected to the discharge pipe ( 140), and a controller 150 for controlling the suction pump. The measurement probe 130 is connected to the light source 30 to radiate light into the chamber 200, and is connected to the spectrometer 50 to measure a color change of a sensor stored in the chamber 200. The spectrometer 50 transmits data measured by the measurement probe 130 to an arithmetic device 70 such as a computer or laptop computer.

FIG. 3 is an enlarged perspective view of part A of FIG. 2 , and FIG. 4 is an enlarged exploded perspective view of the chamber 200 of FIG. 2 . The chamber 200 is configured to test the detection ability of the photonic crystal-based color change sensor in a state where VOCs gas flows inside the chamber. Specifically, the chamber 200 includes a chamber body 210 forming an inner space 201, a sensor seating tray 230 accommodated in the inner space 201, and a chamber cover 250 sealing the upper opening of the chamber body. ).

The chamber 200 is made of an aluminum alloy material that does not absorb VOCs gas. The chamber 200 may include an inner wall 215 having a thickness of at least 15 mm or more within the outer wall 214 of the chamber body 210 so as not to be affected by air flowing in or out at a high flow rate. Although referred to as an outer wall and an inner wall for convenience of description, the chamber body 210 is substantially integrally formed.

In the chamber body 210, a gas inlet through hole 211 is formed on one of the two facing side walls and a gas outlet through hole 216 is formed on the other side wall. The gas inlet through-hole 211 and the gas outlet through-hole 216 are disposed not to face each other so that the VOCs gas supplied to the chamber 200 evenly fills the inner space 201 and is then discharged. The inlet through hole 211 may be positioned close to the right corner of the chamber 200 and the gas outlet through hole 216 may be positioned close to the left corner of the chamber 200 to be offset from the gas inlet through hole 211 .

The inner space 201 of the chamber 200 has a minimum volume required for accommodating the sensor so that it can be quickly saturated with VOCs. For example, the external size of the chamber 200 may be 128 mm in width, 70 mm in length, and 40 mm in height, and the size of the inner space 201 is 88 mm in width, 30 mm in length, and 25 mm in height. can be

The gas inlet through hole 211 is coupled to the supply pipe 110 and the gas outlet through hole 216 is coupled to the discharge pipe 120 . The supply pipe 110 may be in selective fluid communication with the VOCs gas supply source 10 to supply VOCs to the chamber 200 . The discharge pipe 120 is connected to the suction pump 140 to discharge the VOCs gas passing through the chamber 200. The controller 150 may control the operation of the pump to adjust the flow rate of the VOCs gas flowing through the inner space 201 of the chamber.

A supply side concentration meter 117 capable of measuring the concentration of VOCs gas flowing through the supply pipe 110 is installed in the supply pipe 110 . A discharge side concentration meter 127 capable of measuring the concentration of VOCs gas flowing through the discharge pipe 120 is installed in the discharge pipe 120 .

As an embodiment, a valve 160 for selective fluid communication with the VOCs gas supply source 10 is further installed in the supply pipe 110. The VOCs gas supply source 10 may be connected to the supply pipe 110 through a valve. In this case, the controller 150 controls the opening and closing of the valve 160 so that the supply pipe 110 is selectively supplied with VOCs gas.

In addition, in order to selectively supply air without VOCs gas to the supply pipe 110, an air compressor 20 may be further connected to the valve 160. In this case, the controller 150 may control the opening and closing of the valve 160 so that the supply pipe 110 receives clean air instead of VOCs gas.

A probe through-hole 251 is formed in the center of the chamber cover 250 so that the measurement probe 130 can be inserted therein. The chamber cover 250 is coupled to the opening of the chamber body 210 so that its lower surface comes into contact with the upper surface of the inner wall 250 . 4, the height of the outer wall 214 of the chamber body 210 is higher than the height of the inner wall 250, and the chamber cover 250 is placed in the space above the upper surface of the inner wall 250 caused by the height difference. . A plurality of bolt fasteners 212 are formed on the upper surface of the inner wall 250 , and a plurality of bolt insertion holes 252 are formed at positions corresponding to the bolt fasteners 212 in the chamber cover 250 . When the chamber cover 250 is fixed to the chamber body 210 with bolts, the cover rim is surrounded by the outer wall 214 of the chamber body 210 .

The chamber 200 further includes a sealing member 270 sealing between the chamber body 210 and the chamber cover 250 . The sealing member 270 is elastic and is configured not to absorb VOCs gas.

The sensor seating tray 230 has a size accommodated in the inner space 201 of the chamber and facilitates sensor replacement. A sensor may be seated on a tray to position the sensor relative to the measurement probe 130 fixed to the chamber cover 250 . The sensor seating tray 230 includes handles 233 and 234 so that the tested sensor can be easily taken out of the chamber 200 . In order to increase the accuracy of measuring the reflected light wavelength of the sensor, the sensor seating tray 230 is made of a black aluminum material.

The controller 150 may control the operation of the suction pump 140 to adjust the flow rate of the VOCs gas flowing through the inner space 201 of the chamber. Hereinafter, specific functions of the controller 150 will be described in detail along with a method for inspecting the sensing ability of a sensor according to an embodiment of the present invention.

5 is a flowchart of a method for inspecting the sensing ability of a sensor according to an embodiment of the present invention. In the method for testing the detection ability of a sensor according to an embodiment of the present invention, the step of measuring the initial reflected light wavelength (W _initial ) of the VOCs detection sensor (S110), and then supplying VOCs gas into the chamber for a first time ( S120), measuring the reflected light wavelength (W _exposed ) of the sensor while supplying VOCs gas to the chamber for a second time after the lapse of the first time (S130), stopping the supply of VOCs gas and removing VOCs gas for a third time Measuring the reflected light wavelength (W _return ) of the sensor while supplying air to the chamber (S140), and analyzing the bandgap shift of the VOCs detection sensor based on the measurement data (S150).

However, the step of selectively measuring the reflected light wavelength (W _return ) for the third time (S140) can be omitted.

First, in order to test the detection ability of the VOCs detection sensor, after fixing the sensor on the sensor mounting tray 230, placing the tray in the inner space 201 of the chamber, and fixing the chamber cover 250 to the chamber body 210 with bolts. do.

In the step of measuring the initial reflected light wavelength (W _initial ) (S110), the measuring probe 130 measures the initial reflected light wavelength of the sensor for an initial time before the VOCs gas is supplied to the chamber 200. For example, the initial time may be 50 seconds. In addition, the measurement probe 130 may measure the wavelength multiple times by measuring the initial reflected light wavelength (W _initial ) of the sensor once per second. In the initial time, the pump does not operate because VOCs gas is not supplied.

For accurate measurement, a VOCs gas supply source is not connected to the supply pipe 110. In the case of the embodiment in which the valve 160 is installed in the supply pipe 110, the operation of the valve is controlled by the controller 150 to cut off the connection with the VOCs gas supply source.

In the step of supplying VOCs gas into the chamber for the first time (S120), after the initial time has elapsed, the controller 150 controls the operation of the suction pump 140 to supply the VOCs gas to the chamber 200 at a first gas flow rate. supplied with The first time may be a time required for the concentrations of the VOCs gas measured by the supply-side concentration meter 117 and the discharge-side concentration meter 127 to be equal to or greater than a predetermined concentration. Here, the predetermined concentration may be at least the same as the concentration of VOCs gas in the target inner space 201 of the chamber. Also, the predetermined temperature may be determined based on a minimum concentration for measuring the sensitivity of the sensor.

Additionally or alternatively, the first time may be a time required for the concentration of VOCs gas measured by the supply-side concentration meter 117 and the discharge-side concentration meter 127 to be the same or almost similar.

Measuring the reflected light wavelength (W _exposed ) of the sensor while supplying VOCs gas to the chamber for a second time after the lapse of the first time (S130) is a controller to maintain a uniform VOCs gas concentration in the chamber for a second time ( 150 controls the operation of pump 140 to flow VOCs gas at a second gas flow rate. In addition, the measurement probe 130 may measure the wavelength multiple times during the second time by measuring the reflected light wavelength (W _exposed ) of the sensor once per second.

Here, the second gas flow rate is slower than the first gas flow rate. For example, the first gas flow rate may be 10 L/min and the second gas flow rate may be 0.5 L/min. However, it is not limited thereto, and the first gas flow rate may be any speed required to saturate the inner space 201 of the chamber to a specific gas concentration in a short time. Also, the second gas flow rate may be any rate that can keep the concentration of the VOCs gas saturated in the chamber 200 constant for the second time period. And the second time may be a time taken until the reflected light wavelength of the sensor does not change any more in a state in which the sensor is exposed to the VOCs gas flowing at the second gas flow rate.

Stopping the supply of VOCs gas and supplying air without VOCs gas to the chamber for a third time and measuring the reflected light wavelength (W _return ) of the sensor (S140), first after the second time has elapsed, the controller 150 stops the operation of the pump 140 so that the supply of VOCs gas is stopped. In addition, the valve of the supply pipe 110 connected to the VOCs gas supply source is closed, and an air compressor is connected to the supply pipe 110 instead to supply clean air without VOCs air to the chamber inner space 201, and the reflected light wavelength (W _return ) of the sensor to measure

As described above, the valve 160 may be further configured so that the supply pipe 110 is automatically in fluid communication with the VOCs gas supply source 10 and the air compressor 20 selectively and fluid communication is released. In addition, the controller 150 may control the valve so that the supply pipe 110 is selectively in fluid communication with only one of the VOCs gas supply source and the air compressor.

Analyzing the bandgap shift of the VOCs detection sensor based on the measurement data (S150) will be described in detail in the following experimental examples.

Experimental example

In order to prepare the VOCs source 10 with a certain concentration to be exposed to the sensor, after filling a 30L tedlar bag with air with an air compressor, a liquid VOCs solution (benzene, toluene, o -xylene, acetone) It was injected to a target concentration (ppm). The Tedlar bag was put in a constant temperature stirrer and stirred at 120 (rpm) at 25 ° C for 12 hours or more to sufficiently vaporize the liquid VOCs. After that, the tedler bag was connected to the supply pipe 110 through the valve.

The VOCs detection sensor was fabricated using a photonic crystal structure and PDMS (polydimethylsiloxane) material.

The change in wavelength of the sensor was measured using a digital spectrometer (HRP-S250, Ocean Optics Inc., USA) and a light source (HL-2000-FHS, Ocean Optics Inc., USA), electrically connected to the spectrometer and light source. The connected measuring probe 130 was installed on the chamber lid 250. The laptop computer was wired or wirelessly connected to the spectrometer, and the reflected light wavelength of the sensor was measured multiple times at 1-second intervals.

First, the wavelength (W _initial ) was measured for 50 seconds, which is the initial time not exposed to VOCs. Then, VOCs were injected into the inner space 201 of the chamber at a first gas flow rate of 10 L/min for 10 seconds. That is, the pump 140 is operated by the controller 150 so that VOCs gas is supplied into the chamber at a flow rate of 10 L/min. 10 seconds is the time taken for both the VOCs gas concentration in the supply pipe and the VOCs gas concentration in the discharge pipe to reach 100 ppm.

Then, the pump 140 is operated by the controller 150 to supply VOCs gas into the chamber at a second gas flow rate of 0.5 L/min, maintaining the VOCs gas concentration inside the chamber for several minutes while reflecting light from the sensor exposed to the VOCs gas The wavelength (W _exposed ) was measured. Depending on the reaction speed of the sensor, it takes 3 to 6 minutes.

When there is no longer a change in the wavelength of the sensor, the operation of the pump 140 is stopped to stop the supply of VOCs gas, and an air compressor is connected to the supply pipe 110 instead of the tetherer bag to inject clean air without VOCs gas. Measure the reflected light wavelength (W _return ) of the sensor every second while injecting clean air for more than 3 minutes. The measurement ends when the sensor's reflected light wavelength does not change any more.

6 is a graph obtained by measuring and analyzing the wavelength of reflected light of a sensor exposed to 100 ppm o -Xylene gas over time. In this graph, the wavelength of the reflected light of the sensor is continuously measured even while supplying o -Xylene gas at a rate of 10 L/min to saturate the chamber with VOCs gas, and the wavelength is displayed for all times. In the intensity data for each wavelength measured with a spectrometer, the peak wavelength, which is the wavelength value with the highest intensity per time, was calculated using MATLAB (MathWorks, USA), and the detection ability of the sensor was analyzed as shown in FIG. 6 (a). . o -The average of 30 wavelength measurements before injecting xylene gas is set as the initial reflected light wavelength (W _initial ), and the average of 100 wavelength measurements before air injection is set as the reflected light wavelength (W _exposed ), o - The bandgap shift (nm) of the sensor exposed to xylene gas was analyzed.

To evaluate the precision of the sensor, five or more consecutive experiments were conducted for the same VOCs gas. As shown in Equation 1, the precision was calculated through the relative standard deviation (%RSD), and the smaller the value, the higher the precision.

s: standard deviation, x: mean

When exposed to low-concentration o -Xylene gas around 100ppm, there was difficulty in quantitative evaluation due to the noise of the spectrometer. Therefore, instead of finding the wavelength with the highest intensity and deriving the peak wavelength and arithmetic average, the weighted arithmetic average with intensity applied as a weight-factor was analyzed with MATLAB. Using a spectral analysis method that finds the spectral centroid using weighted arithmetic average, amplifies the signal to noise ratio (SNR) generated from a small amount of change to determine the change in wavelength by o -Xylene gas, that is, the band Gap movement could be analyzed separately from noise. 6(b) is a graph obtained by analyzing the sensing ability of the sensor by the 'center spectrum method' using the weighted arithmetic mean. As shown in (a) of FIG. 6, it can be seen that the band gap shift, which was difficult to confirm by the park wavelength method, can be confirmed by analyzing according to the center spectrum method.

The results of analyzing the band gap shift through a total of five experiments are shown in Table 1 below.

In the above, the preferred embodiments of the present invention have been described in detail, but the technical scope of the present invention is not limited to the above-described embodiments and should be interpreted according to the claims. At this time, those skilled in the art should consider that many modifications and variations are possible without departing from the scope of the present invention.

Claims (16)

a chamber configured to test the sensing ability of the photonic crystal-based color change sensor while flowing a gas to be sensed;
a measurement probe electrically connected to a light source and a spectrometer and installed in the chamber to measure a color change of the sensor;
a supply pipe connected to the chamber;
a discharge pipe connected to the chamber;
a suction pump connected to the discharge pipe; and
Including a controller for controlling the operation of the pump to adjust the flow rate of the gas to be sensed flowing in the chamber,
A device for inspecting the detectability of a sensor. According to claim 1,
The measurement probe measures the initial reflected light wavelength of the sensor housed in the chamber during an initial time when the pump is not operated,
The controller may supply the target gas to the chamber at a first gas flow rate for a first time after the initial time has elapsed, and supply the target gas to the chamber at a second gas flow rate for a second time thereafter. to control,
The measuring probe measures the reflected light wavelength of the sensor housed in the chamber during the second time,
A device for inspecting the detectability of a sensor. According to claim 2,
a supply-side concentration meter coupled to the supply pipe to measure the concentration of the target gas to be detected in the supply pipe; and
Further comprising a discharge side concentration meter coupled to the discharge pipe and capable of measuring the concentration of the gas to be detected in the discharge pipe,
The first time is the time taken until both the concentration measured by the supply-side concentration meter and the concentration measured by the exhaust gas concentration meter reach a predetermined concentration,
A device for inspecting the detectability of a sensor. According to claim 2,
The second gas flow rate is slower than the first gas flow rate,
A device for inspecting the detectability of a sensor. According to claim 2,
Further comprising a valve installed in the supply pipe so that the supply pipe is in selective fluid communication with a source of the gas to be sensed or an air compressor,
The controller,
Control the valve so that the supply pipe is in fluid communication with the supply source of the gas to be sensed during the first time and the second time,
After the second time has elapsed, the supply pipe is in fluid communication with the air compressor for a third time to control the valve so that air without a target gas to be sensed flows into the supply pipe,
Stop the operation of the pump for the third time,
The measuring probe,
Measuring the reflected light wavelength of the sensor housed in the chamber during the third time,
A device for inspecting the detectability of a sensor. According to claim 1,
The chamber is made of a material containing aluminum and is opaque,
A device for inspecting the detectability of a sensor. According to claim 1,
Further comprising a sensor seating tray accommodated in the chamber and positioning the sensor relative to the measurement probe.
A device for inspecting the detectability of a sensor. According to any one of claims 1 to 7,
The gas to be detected is a volatile organic compound (VOCs) gas,
The sensor is a photonic crystal-based color change sensor in which a photonic crystal arrangement changes when exposed to VOCs gas,
A device for inspecting the detectability of a sensor. In a chamber in which a photonic crystal-based color change sensor is housed and a measurement probe electrically connected to a spectrometer and a light source is installed, measuring an initial reflected light wavelength of the sensor for an initial time before a target gas is supplied to the chamber;
supplying a target gas to the chamber at a first gas flow rate for a first time after the initial time has elapsed; and
Measuring a reflected light wavelength of the sensor while supplying a target gas to the chamber at a second gas flow rate for a second time after the first time has elapsed,
How to test the detectability of a sensor. According to claim 9,
The first time is the time taken until both the concentration in the supply pipe of the target gas supplied to the chamber and the concentration in the discharge pipe of the target gas discharged from the chamber reach a predetermined concentration,
How to test the detectability of a sensor. According to claim 9,
The second gas flow rate is slower than the first gas flow rate,
How to test the detectability of a sensor. According to claim 9,
The second time is the time taken until the reflected light wavelength of the sensor does not change any more in a state in which the sensor is exposed to the target gas flowing at the second gas flow rate,
How to test the detectability of a sensor. According to claim 9,
Stopping the supply of the target gas for a third time after the second time has elapsed and measuring the reflected light wavelength of the sensor while supplying air without the target gas to the chamber,
How to test the detectability of a sensor. According to claim 9,
Further comprising analyzing the bandgap shift of the sensor by comparing wavelengths of reflected light of the sensor before and after being exposed to the gas to be detected,
In the step of measuring the wavelength of the initial reflection light of the sensor, the wavelength of the initial reflection light is measured n or more times at equal time intervals;
In the step of measuring the reflected light wavelength of the sensor while supplying the target gas to the chamber at a second gas flow rate, measuring the reflected light wavelength of the sensor m or more times at equal time intervals during a second time,
Analyzing the bandgap shift of the sensor,
Analyzing the bandgap shift based on the average value of n initial reflected light wavelengths and the average value of m reflected light wavelengths measured for a second time,
How to test the detectability of a sensor. According to claim 14,
Analyzing the bandgap shift of the sensor,
Analyzing the bandgap shift by weighting arithmetic average of the m reflected light wavelengths measured during the second time with the intensity as a weight,
How to test the detectability of a sensor. According to any one of claims 9 to 15,
The gas to be detected is a volatile organic compound (VOCs) gas,
The sensor is a photonic crystal-based color change sensor in which a photonic crystal arrangement changes when exposed to VOCs gas,
How to test the detectability of a sensor.

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