TW201809630A - Gas detection device and method for detecting gas concentration - Google Patents

Abstract

The instant disclosure provides a gas detection device and method for detecting gas concentration. The gas detection device includes a chamber module, a light module, an optical sensing module, and a light splitting module. The chamber module includes a light guide chamber, a first sampling chamber, and a second sampling chamber. The light module disposed on the light guide chamber to generate a projection light beam. The optical sensing module includes a first optical sensing unit which disposed in the first sampling chamber, and a second optical sensing unit which disposed in the second sampling chamber. The light splitting module disposed in the chamber module. The projection light beam splitting by the light splitting module to generate a first splitting light beam and a second splitting light beam.

Description

Gas measuring device and gas concentration measuring method

The invention relates to a gas measuring device and a gas concentration measuring method, in particular to a gas measuring device and a gas concentration measuring method capable of simultaneously measuring different gas concentrations.

First of all, the carbon dioxide detection devices or carbon dioxide analyzers currently on the market almost all use the non-dispersive infrared (NDIR) absorption method to detect the gas concentration, which is mainly based on the Beer-Lambert law. Beer-Lambert law) for calculations. Its principle is to use a gas to absorb the specific wavelength of infrared rays and the concentration of gas is proportional to the amount of absorption to detect a specific gas concentration. For example, carbon monoxide has the strongest absorption of 4.7 micrometer (μm) wavelength and carbon dioxide to infrared light having a wavelength of 4.3 micrometers (μm).

However, the measurement accuracy of the gas concentration measuring device currently on the market is still limited by the structural design of the gas sampling chamber, and it is only possible to measure the gas in a specific concentration range. In terms of non-dispersive infrared absorption method to detect gas concentration, the absorption intensity of gas by infrared rays will be proportional to the length and concentration. However, the length of the gas sampling chamber of the existing gas concentration measuring device is only a single and fixed length. In the case where the sampling chamber length is too long and the gas concentration to be measured is high, the high concentration gas will be excessively absorbed and emitted. The infrared energy generated by the unit causes the light sensing unit to receive no signal and cannot measure a high concentration of gas. In addition, in the case where the length of the sampling chamber is too short and the gas concentration to be measured is low, it will be due to the low concentration of gas to the infrared. The absorption of the line is extremely small, and the distance from the infrared energy generated by the light-emitting unit to the light-sensing unit is short, and the infrared energy is projected onto the light-sensing unit with little absorption. Moreover, when the infrared energy received by the light sensing unit is too low, it is easy to cause an inaccurate measurement accuracy due to noise interference.

Further, the gas concentration measuring device currently available on the market can only measure one gas and cannot measure at the same time for a plurality of gases.

Therefore, how to provide an environment capable of measuring a plurality of different gases or measuring a gas having a large difference between high and low concentrations to overcome the above-mentioned defects has become an important subject to be solved by the technology.

The technical problem to be solved by the present invention is to provide a gas measuring device and a gas concentration measuring method for the deficiencies of the prior art. The gas measuring device and the gas concentration measuring method provided by the invention can simultaneously measure a plurality of different gases by using one light emitting module corresponding to a plurality of light sensing units, or can be suitable for measuring an environment with a large difference between high and low gas concentrations.

One of the technical solutions adopted by the present invention is to provide a gas measuring device, which comprises a cavity module, a light emitting module, a light sensing module and a beam splitting module. The cavity module includes a light guiding cavity, a first sampling cavity connected to the light guiding cavity, and a second sampling cavity connected to the light guiding cavity. The light emitting module is disposed in the light guiding cavity, and the light emitting module is configured to generate a projected light beam. The light sensing module includes a first light sensing unit disposed in the first sampling cavity and a second light sensing unit disposed in the second sampling cavity. The beam splitting module is disposed in the cavity module. The projection light beam generated by the light emitting module is split by the light splitting module to form a first split light beam directed to the first light sensing unit and a second light sensing unit The second beam of light.

Another technical solution adopted by the present invention is to provide a gas concentration measuring method, the gas concentration measuring method comprising: providing a light emitting module, the light emitting The module generates a first split beam that is projected through a first sampling cavity onto a first photo sensing unit, and the illumination module generates a second sampling cavity to project to a second light. a second beam splitting beam on the sensing unit, wherein a size of the first sampling cavity is larger than a size of the second sampling cavity, the first sampling cavity has a first gas, and the second sampling Having a second gas in the cavity; calculating a first tangential slope of the first beam splitting beam energy received by the first light sensing unit relative to a first curve equation, and calculating the second light a second tangential slope of the second split beam energy received by the sensing unit relative to a second curve equation; and determining whether an absolute value of the first tangential slope is greater than an absolute value of the second tangential slope Wherein, when an absolute value of the first tangent slope is greater than an absolute value of the second tangent slope or an absolute value of the first tangent slope is equal to an absolute value of the second tangent slope, an output Concentration of the first gas ; Wherein, when the absolute value of the slope is less than the first tangent line tangent slope of the second absolute value, the output of the second gas concentration.

Another technical solution adopted by the present invention is to provide a gas concentration measuring method, the gas concentration measuring method comprising: providing a light emitting module, wherein the light emitting module generates a first sampling cavity to project to a first a first beam splitting light on a light sensing unit, and the light emitting module generates a second splitting light beam that is projected through a second sampling cavity onto a second light sensing unit, wherein the first sampling The size of the cavity is larger than the size of the second sampling cavity; and the concentration of a first gas in the first sampling cavity is calculated according to a first beam splitting energy received by the first photo sensing unit, And calculating a concentration of a second gas in the second sampling cavity according to a second beam splitting energy received by the second photo sensing unit; and determining a concentration of the first gas and the second Whether the concentration of the gas is greater than a predetermined threshold; wherein, when the concentration of the first gas and the concentration of the second gas are greater than the predetermined threshold, the concentration of the second gas is output; wherein Dang Concentration of the first gas and the second gas concentration less than the preset threshold value or is equal to the preset threshold, the output of the first gas concentration.

The utility model has the beneficial effects that the gas measuring device and the gas concentration measuring method provided by the embodiments of the invention utilize the technical features of the “splitting module”, so that the projection beam generated by the light emitting module can be split by the beam splitting module. And forming a first split beam directed to the first photo sensing unit and a second split beam directed to the second photo sensing unit. Meanwhile, the first light sensing unit can be used to measure the properties of the first gas, the second sensing unit can be used to measure the properties of the second gas, and further, through the first light sensing unit and the second light sensing unit The first split beam and the second split beam generated by the projection beam can be applied to an environment where the difference between the high and low concentrations of the gas is measured. In other words, the projected beam generated by the light emitting module forms at least two or more splitting beams to respectively correspond to at least two of the light sensing units.

For a better understanding of the features and technical aspects of the present invention, reference should be made to the accompanying drawings.

Q, Q’‧‧‧ gas measuring device

1,1'‧‧‧ cavity module

11‧‧‧Lighting cavity

111‧‧‧Light guiding space

112‧‧‧reflecting surface

12‧‧‧First sampling chamber

121‧‧‧First sampling space

122‧‧‧First accommodation space

123‧‧‧First gas diffusion tank

13‧‧‧Second sampling chamber

131‧‧‧Second sampling space

132‧‧‧Second accommodation space

133‧‧‧Second gas diffusion tank

14‧‧‧ third sampling chamber

141‧‧‧ third sampling space

142‧‧‧ third accommodating space

143‧‧‧ Third gas diffusion tank

15‧‧‧four sampling chamber

151‧‧‧fourth sampling space

152‧‧‧ fourth accommodating space

153‧‧‧fourth gas diffusion tank

2‧‧‧Lighting module

21‧‧‧Lighting unit

22‧‧‧Connecting line

3‧‧‧Light sensing module

31‧‧‧First light sensing unit

32‧‧‧Second light sensing unit

33‧‧‧ Third Light Sensing Unit

34‧‧‧Fourth light sensing unit

35‧‧‧Connecting line

4‧‧‧Distribution Module

41‧‧‧The first specular surface

42‧‧‧Second specular surface

43‧‧‧The third specular surface

44‧‧‧ fourth specular surface

5‧‧‧Substrate module

51‧‧‧ arithmetic unit

52‧‧‧Display unit

T‧‧‧projection beam

T1‧‧‧first split beam

T11‧‧‧first projection beam

T12‧‧‧First reflected beam

T13‧‧‧first incident beam

T2‧‧‧Second split beam

T21‧‧‧second projection beam

T22‧‧‧second reflected beam

T23‧‧‧second incident beam

F‧‧‧ focus

P‧‧‧ optical axis

I‧‧‧ center axis

L1‧‧‧First preset length

L2‧‧‧Second preset length

X, Y, Z‧‧ Direction

S102~S110, S202~S210‧‧‧ steps

X1, x2, x3, x4‧‧‧ concentration values

X5‧‧‧Preset threshold

1 is a schematic perspective view of one of the gas measuring devices of the first embodiment of the present invention.

2 is a perspective exploded view of the gas measuring device of the first embodiment of the present invention.

3 is a block diagram of a module of a gas measuring device according to a first embodiment of the present invention.

Figure 4 is a cross-sectional view taken along line IV-IV of Figure 1.

Fig. 5 is a schematic view showing a light beam projection of the gas measuring device according to the first embodiment of the present invention.

Fig. 6 is a schematic view showing another beam projection of the gas measuring device of the first embodiment of the present invention.

Fig. 7 is a schematic cross-sectional view taken along line VII-VII of Fig. 1;

Figure 8 is a side cross-sectional view showing another embodiment of the gas measuring device of the first embodiment of the present invention.

Figure 9 is a perspective assembled view of a gas measuring device according to a second embodiment of the present invention.

Fig. 10 is a cross-sectional view taken along line X-X of Fig. 9.

Figure 11 is a flow chart showing one of the gas concentration measuring methods of the third embodiment of the present invention.

Figure 12 is a schematic diagram of one of the curve equations of the third embodiment of the present invention.

Figure 13 is a schematic diagram of another curve equation according to a third embodiment of the present invention.

Figure 14 is a flow chart showing another flow of the gas concentration measuring method according to the third embodiment of the present invention.

Figure 15 is a flow chart showing a gas concentration measuring method according to a fourth embodiment of the present invention.

The following is a description of an embodiment of the present invention relating to a "gas measuring device and a gas concentration measuring method" by a specific specific example, and those skilled in the art can understand the advantages and effects of the present invention from the contents disclosed in the present specification. The present invention may be carried out or applied in various other specific embodiments, and various modifications and changes can be made without departing from the spirit and scope of the invention. In addition, the drawings of the present invention are merely illustrative and are not intended to be construed in terms of actual dimensions. The following embodiments will further explain the related technical content of the present invention, but the disclosure is not intended to limit the technical scope of the present invention.

First embodiment

First, referring to FIG. 1 to FIG. 4, a first embodiment of the present invention provides a gas measuring device Q for measuring a concentration of a gas, which includes a cavity module 1, a light emitting module 2, and a The light sensing module 3, a light splitting module 4, and a substrate module 5. The light-emitting module 2 and the light-sensing module 3 are electrically connected to the substrate module 5, and the substrate module 5 includes a display unit 52 for displaying the concentration value of the gas and an operation for calculating the gas concentration. Unit 51. Further, the computing unit 51 is electrically connected to the display unit 52, the light emitting module 2, and the light sensing module 3. In addition, for example, the light-emitting module 2 can be an infrared illuminator that generates an infrared light source, and the light sensing module 3 It is an infrared light sensor, for example, a single-channel infrared light sensor or a two-channel infrared light sensor (one infrared collection window can be used to detect gas concentration, and another infrared collection window can be used to detect infrared light). Whether the light source is aging or not, and the function of mutual correction is also included, but the invention is not limited thereto.

Therefore, the gas measuring device Q provided by the embodiment of the present invention can measure the concentration of the gas to be detected or other properties. Incidentally, the gas to be detected may be a combination of carbon dioxide, carbon monoxide or carbon dioxide and carbon monoxide, and the present invention does not wait for The detection gas is a limitation. In other words, different gases to be detected can be measured by different light-emitting modules 2 and light-sensing modules 3. For example, in order to measure different gas concentrations, different wavelengths of the gas to be detected can be measured by changing the wavelength filter (filter) on the light sensing module 3.

As shown in FIG. 2 to FIG. 4 , the cavity module 1 includes a light guiding cavity 11 , a first sampling cavity 12 connected to the light guiding cavity 11 , and a first connecting cavity 11 connected to the light guiding cavity 11 . The second sampling chamber 13 , that is, the light guiding cavity 11 is disposed between the first sampling cavity 12 and the second sampling cavity 13 , but the invention is not limited thereto. It is to be noted that, in order to be able to measure an environment in which the difference between the high and low concentrations of the same gas is large, the size of the first sampling chamber 12 and the size of the second sampling chamber 13 are different from each other, in the embodiment of the present invention, The size of the sampling chamber 12 is greater than the size of the second sampling chamber 13 , that is, the length of the first sampling chamber 12 is greater than the length of the second sampling chamber 13 , but the invention is not limited thereto. It should be noted that, in other implementation manners, the size of the first sampling cavity 12 may not be limited to be the same as or different from the size of the second sampling cavity 13 as long as the first light sensing unit 31 and the second light are caused. The sensing unit 32 is respectively adapted to measure a first gas and a second gas that are different from each other. In other words, the first light sensing unit 31 can be adapted to measure the properties of a first gas, and the second light sensing unit 32 can be adapted to measure the properties of a second gas, and both the first gas and the second gas Different from each other. Thereby, one light-emitting module 2 can be used to correspond to two or more light sensing units to measure an environment that causes a difference in the height difference between the same gas, or simultaneously measure the properties of different gases.

For example, in the embodiment of the present invention, the longitudinal direction (X direction) of the first sampling cavity 12 and the longitudinal direction (Y direction) of the light guiding cavity 11 are substantially perpendicular to each other, and the second sampling cavity 13 is provided. The longitudinal direction (X direction) and the longitudinal direction (Y direction) of the light guiding cavity 11 are substantially perpendicular to each other, but the invention is not limited thereto. In other words, in other embodiments, the length direction of the first sampling cavity 12 and the length direction of the second sampling cavity 13 may also be in the Z direction (for example, the second embodiment provides Both the longitudinal direction of the three sampling chambers 14 and the longitudinal direction of the fourth sampling chamber 15 are disposed along the Z direction. In addition, it should be noted that in another embodiment, the longitudinal direction of the first sampling cavity 12 and the longitudinal direction of the second sampling cavity 13 may also be substantially parallel to the longitudinal direction of the light guiding cavity 11 ( Not shown in the drawing, that is, the longitudinal direction of the light guiding cavity 11, the longitudinal direction of the first sampling cavity 12, and the longitudinal direction of the second sampling cavity 13 are all disposed along the Y direction.

Next, as shown in FIG. 4, the light guiding cavity 11 has a light guiding space 111 and a reflecting surface 112. The first sampling cavity 12 has a first sampling space 121 and a first receiving space 122, and the second sampling. The cavity 13 has a second sampling space 131 and a second accommodating space 132. The light guiding space 111, the first sampling space 121 and the second sampling space 131 communicate with each other. In addition, the light-emitting module 2 can be disposed in the light-guiding cavity 11 , and the light-emitting module 2 can include a light-emitting unit 21 and a connecting line 22 electrically connected to the substrate module 5 (the connecting line 22 is not shown) The substrate module 5 is connected to provide electrical energy to cause the illumination unit 21 to generate a projection beam T (see FIGS. 5 and 6), such as infrared light. In addition, the light sensing module 3 includes a first light sensing unit 31 and a second light sensing unit 32. The first light sensing unit 31 can be disposed in the first receiving space 122, and the second light sensing unit The unit 32 can be disposed in the second accommodating space 132 to receive the projected light beam T generated by the light emitting unit 21. The connection line 35 of the light sensing module 3 (the connection line 35 of the first light sensing unit 31 and the connection line 35 of the second light sensing unit 32) can be electrically connected to the substrate module 5 (not shown in the figure) The connection line 35 is connected to the substrate module 5). It should be noted that the present invention is not limited to whether the light guiding space 111, the first sampling space 121, and the second sampling space 131 are connected to each other.

The first sampling space 121 of the first sampling chamber 12 and the second sampling space 131 of the second sampling chamber 13 may have a rectangular shape, such as a rectangular shape, but the invention is not limited thereto. Each surface inside the first sampling cavity 12 and the second sampling cavity 13 may be provided with a reflective layer (not shown), and the reflective layer may be formed by metal plating or plastic plating. The reflective layer may be composed of a gold-containing metal, a nickel metal, or a mixture of a gold metal and a nickel metal. Thereby, the first sampling cavity 12 and the second sampling cavity 13 of a rectangular shape are like the same rectangular optical integrator, whereby the projection beam T generated by the illumination module 2 passes through the reflective layer in the first sampling space. 121 and the second sampling space 131 are reflected back and forth, so that the projection light beams T generated by the light-emitting module 2 are superimposed on each other, so that the superimposed light can be evenly distributed. It is worth mentioning that a reflective layer can also be disposed on the reflective surface of the light guiding cavity 11 to improve the reflection efficiency and increase the amount of light that the light emitting module 2 projects onto the beam splitting module 4.

Then, as shown in FIG. 4 to FIG. 6 , the beam splitting module 4 can be disposed between the first sampling cavity 12 and the second sampling cavity 13 , and the projection beam T generated by the light emitting module 2 passes through the beam splitting module 4 . The light is split to form a first split light beam T1 directed to the first light sensing unit 31 and a second split light beam T2 directed to the second light sensing unit 32. For example, the beam splitting module 4 includes a first beam splitting surface 41 and a second beam splitting surface 42. Thereby, the projected light beam T generated by the light emitting unit 21 can be formed by the first light splitting surface 41 and the second light splitting surface 42 to be projected onto the first light splitting beam T1 on the first light sensing unit 31, and projected to the first The second beam splitting beam T2 on the second light sensing unit 32. It should be noted that the beam splitting module 4 is not limited to the prism shown in the drawing. In other embodiments, the beam splitting module 4 may also be a projection beam T generated by the light emitting unit 21 by using a plurality of beam splitters. A first beam splitting beam T1 and a second beam splitting beam are formed.

As shown in FIG. 5, preferably, the reflecting surface 112 of the light guiding cavity 11 is a paraboloid, the parabolic mask has a focus F, and the light emitting unit 21 is disposed corresponding to the focus F, that is, the light emitting unit 21 can be disposed on the focus F and the focus. F coincides. By means of parabolic design A first projection beam T11 and a second projection beam T21 projected by the illumination unit 21 on the light guiding cavity 11 can be uniformly reflected by the paraboloid onto the beam splitting module 4. In addition, in order to improve the reflection efficiency of the paraboloid, the parabolic surface may be provided with the reflection layer described above.

In the above, specifically, the projection beam T includes a first projection beam T11 and a second projection beam T21 projected onto the light guiding cavity 11, and the first projection beam T11 can be reflected by the paraboloid of the light guiding cavity 11. To form a first reflected light beam T12 that is projected onto the first light splitting surface 41 of the beam splitting module 4, the first reflected light beam T12 is reflected by the first light splitting surface 41 to form a projection onto the first light sensing unit 31. The first beam splitting beam T1. In addition, the second projection beam T21 is reflected by the light guiding cavity 11 to form a second reflected light beam T22 projected to the second beam splitting surface 42 of the beam splitting module 4, and the second reflected beam T22 passes through the second beam splitting surface 42. Reflecting to form a second beam splitting beam T2 projected onto the second photo sensing unit 32.

In addition, as shown in FIG. 6 , the projection light beam T generated by the light-emitting unit 21 further includes a first incident light beam T13 directly projected on the first light-splitting surface 41 of the beam splitting module 4 , and directly projected on the beam splitting module 4 . A second incident beam T23 of the second beam splitting surface 42. The first incident light beam T13 is reflected by the first light splitting surface 41 to form a first split light beam T1 projected onto the first light sensing unit 31, and the second incident light beam T23 is reflected by the second light splitting surface 42 to form A second beam splitting beam T2 projected onto the second photo sensing unit 32.

In other words, the projected light beam T generated by the light emitting unit 21 includes a first split light beam T1 projected onto the first light sensing unit 31 and a second split light beam T2 projected onto the second light sensing unit 32. The first split light beam T1 projected onto the first light sensing unit 31 may be formed by the first projected light beam T11, the first reflected light beam T12, and the first incident light beam T13. The second split light beam T2 projected onto the second light sensing unit 32 may be formed by the second projected light beam T21, the second reflected light beam T22, and the second incident light beam T23. It should be noted that, in the case where the light guiding cavity 11 is not provided with the reflecting surface 112, the first beam splitting light beam T1 projected onto the first light sensing unit 31 may be straight. The first incident light beam T13 is formed by the first incident light beam T13, and the second split light beam T2 projected onto the second light sensing unit 32 can be directly formed by the second incident light beam T23.

In addition, the first sampling cavity 12 is further provided with a first gas diffusion groove 123, and the second sampling cavity 13 is further provided with a second gas diffusion groove 133. In addition, the first gas diffusion groove 123 and the second gas diffusion groove 133 may have a rectangular shape. The cross-sectional shape of the first gas diffusion groove 123 and the second gas diffusion groove 133 may be a V as shown in FIGS. 5 to 7 . The shape of the glyph causes the gas to be detected to pass through the Bernoulli's principle, and allows the gas to flow through the V-shaped first gas diffusion groove 123 and the second gas diffusion groove 133, due to the size of the V-shaped shape. Change, and let the gas flow rate get faster, so that the gas spreads faster and the measurement time is shortened. It is worth mentioning that a gas filtering membrane (not shown) may be further disposed on the first gas diffusion tank 123 and the second gas diffusion tank 133. For example, the gas filtration membrane may be a waterproof gas permeable membrane. The suspended particles of the gas to be detected can be prevented from entering the first sampling space 121 and the second sampling space 131, causing internal pollution or affecting measurement accuracy.

It should be noted that, in the embodiment of the present invention, in order to be able to measure an environment with a large difference between high and low gas concentrations, the first sampling cavity 12 has a first preset length L1, and the second sampling cavity 13 has a second. The first predetermined length L1 of the first sampling cavity 12 may be greater than the second preset length L2 of the second sampling cavity 13 by a preset length L2. Thereby, the first sampling cavity 12 is compared with the second sampling cavity 13, the first sampling cavity 12 is suitable for measuring a lower concentration of gas, and the second sampling cavity 13 is suitable for measuring a higher concentration. gas. At the same time, since the first splitting light beam T1 and the second splitting light beam T2 respectively received by the first light sensing unit 31 and the second light sensing unit 32 are generated by the same light emitting unit 21, the error value is measured. Smaller.

Referring to FIG. 5, FIG. 6 and FIG. 8 together, it can be seen from comparison between FIG. 8 and FIG. 5 that in other embodiments, the position of the spectroscopic module 4 can be adjusted to adjust the first light sensing. The light energy that the unit 31 and the second light sensing unit 32 can receive. Specifically, as shown in FIG. 5 and FIG. 6, the light guiding cavity 11 includes a reverse The beam 112 and the optical axis P of a focus F passing through the reflecting surface 112, the beam splitting module 4 has a central axis I between the first beam splitting surface 41 and the second beam splitting surface 42, and the central axis I passes through the light guiding space 111, and both the optical axis P and the central axis I coincide with each other. In addition, as shown in FIG. 8, the optical axis P of the light guiding cavity 11 may not coincide with the central axis I of the beam splitting module 4. In addition, in the present embodiment, since the projection beam T and the first beam splitting beam T1 are perpendicular to each other, and the projection beam T and the second beam splitting beam T2 are perpendicular to each other, the first beam splitting surface 41 is There is an angle of 45 degrees with the central axis I, and the angle between the second beam splitting surface 42 and the central axis I is 45 degrees, but the invention is not limited thereto.

Second embodiment

First, referring to FIG. 9 and FIG. 10, a second embodiment of the present invention provides a gas measuring device Q'. As can be seen from a comparison between FIG. 9 and FIG. 1, the greatest difference between the second embodiment and the first embodiment is that: The cavity module 1' provided by the second embodiment further includes a third sampling cavity 14 connected to the light guiding cavity 11 and a fourth sampling cavity 15 connected to the light guiding cavity 11. The third sampling chamber 14 has a third sampling space 141 and a third accommodating space 142. The fourth sampling chamber 15 has a fourth sampling space 151 and a fourth accommodating space 152. The light guiding space 111, the third sampling space 141, and the fourth sampling space 151 are in communication with each other. In other words, the third sampling space 141 and the fourth sampling space 151 are both in communication with the first sampling space 121 and the second sampling space 131. However, it should be noted that the present invention is not limited to whether the sampling spaces are connected to each other, in other words, as long as the projection light beams T are formed to be respectively projected to the plurality of light sensing units (for example, the first light sensing units 31 and the second The plurality of split light beams (for example, the first split light beam T1 and the second split light beam T2) on the light sensing unit 32) may be used. In addition, the third sampling cavity 14 and the fourth sampling cavity 15 may further be provided with a third gas diffusion groove 143 and a fourth gas diffusion groove 153 as described above, so that the gas diffusion is faster and the measurement time is allowed. shorten.

In the above, the beam splitting module 4 further includes a third beam splitting surface 43 and a first The light-sensing module 3 further includes a third light sensing unit 33 and a fourth light sensing unit 34. The third light sensing unit 33 is disposed in the third receiving space 142. The four-light sensing unit 34 is disposed in the fourth accommodating space 152. Thereby, the projection beam can further form a third beam splitting beam (not shown) directed to the third photo sensing unit through the splitting of the beam splitting module 4, and a projection to the fourth photo sensing unit. The fourth split beam (not shown).

In the above, the projection beam may include a third projection beam (not shown) projected onto the light guiding cavity 11 and a fourth projection beam (not shown), and the third projection beam may pass through the light guiding cavity. The parabolic reflection of the body 11 forms a third reflected beam (not shown) projected onto the third beam splitting surface 43 of the beam splitting module 4, and the third reflected beam passes through the reflection of the first beam splitting surface 41 to form The third split light beam projected onto the third light sensing unit 33. In addition, the fourth projection beam can be reflected by the light guiding cavity 11 to form a fourth reflected beam (not shown) projected onto the fourth beam splitting surface 44 of the beam splitting module 4, and the fourth reflected beam passes through The reflection of the quarter plane 44 forms a fourth beam split that is projected onto the fourth photo sensing unit 34.

In addition, the projection beam T further includes a third incident beam (not shown) directly projected on the third beam splitting surface 43 of the beam splitting module 4, and is directly projected on the fourth beam splitting surface 44 of the beam splitting module 4. A fourth incident beam (not shown). The third incident light beam is reflected by the third light splitting surface 43 to form a third split light beam projected onto the third light sensing unit 33, and the fourth incident light beam is reflected by the fourth light splitting surface 44 to form a projection to The fourth beam splitting light on the fourth light sensing unit 34.

In addition, it should be noted that other structural features provided by the second embodiment of the present invention (eg, the light guiding cavity 11, the first sampling cavity 12, the second sampling cavity 13, the light emitting module 2, the light splitting module 4) And the projection beam T, etc., is similar to the embodiment described above, and will not be described again here. Thereby, by the arrangement of the third sampling cavity 14 and the fourth sampling cavity 15, the measurement range of the gas high and low concentration can be increased, or the properties of various gases (such as the concentration of different gases, etc.) can be increased.

Third embodiment

First, please refer to FIG. 5, FIG. 6 and FIG. 11 simultaneously. The third embodiment of the present invention provides a gas concentration measuring method, and the gas concentration measuring method comprises the following steps. As shown in step S102, a first beam splitting beam T1 is projected through a first sampling chamber 12 onto a first photo sensing unit 31, and a second sampling chamber 13 is provided to project through a second sampling chamber 13. The second beam splitting beam T2 on the second light sensing unit 32. In detail, a light-emitting module 2 can be provided to generate a projection beam T, and the projection beam T can generate a first beam splitting beam T1 and a second beam splitting beam T2 through a beam splitting module 4. It should be noted that, in order to measure the environment where the difference between the high and low concentration of the gas is large, the size of the first sampling cavity 12 is larger than the size of the second sampling cavity 13 . In other words, the length of the first sampling cavity 12 is greater than the second sampling. The length of the cavity 13. For example, in the third embodiment, the first preset length L1 of the first sampling cavity 12 is 4 times longer than the second preset length L2 of the second sampling cavity 13, that is, L1=4L2, where L1 is the first A preset length L1, L2 is a second preset length L2. In addition, it should be noted that in the third embodiment, the projection beam T may be an infrared beam, the first sampling chamber 12 has a first gas, and the second sampling chamber 13 has a second gas. It should be noted that the first gas and the second gas in the third embodiment are described by the same gas (for example, carbon dioxide, CO ₂ ), but the invention is not limited thereto.

Next, as shown in step S104, calculating a first tangent slope of the first split beam energy received by the first light sensing unit 31 with respect to a first curve equation, and calculating the second light sensing unit 32. A second tangential slope of the received second split beam energy relative to a second curve equation. In general, in order to measure the concentrations of the first gas and the second gas, the calculation unit 51 in the substrate module 5 can be used to calculate according to the Beer-Lambert law. If I ₀ is assumed to be the energy of the infrared incident light (the initial energy before the infrared ray is absorbed by the gas); I _t is the infrared energy received by the infrared light sensing unit (after the infrared ray is absorbed by the gas, the infrared light sensing unit receives Energy is); K is the absorption coefficient, that is, the absorption coefficient of the gas to the light; L is the total light path length through which the gas absorbs light; C is the concentration of the gas. Therefore, according to the formula of Beer-Lambert's law, the following relationship can be obtained: I _t = I ₀ × exp ×(-( L × K × C ))

Next, referring to FIG. 12 and FIG. 13 together, according to the Beer-Lambert law, f ₁ (x) is defined as a first received by the first light sensing unit 31 in the first sampling cavity 12. A split beam energy, f ₂ (x), is defined as a second split beam energy received by the second photo sensing unit 32 in the second sampling cavity 13. x is the concentration of the first gas or the second gas. In this embodiment, the first preset length L1 of the first sampling cavity 12 is 4 times longer than the second preset length L2 of the second sampling cavity 13 , and therefore, the first in the first sampling cavity 12 The calculation of the concentration of the gas and the calculation of the concentration of the second gas in the second sampling chamber 13 can be defined as the following relationship: f ₁ ( x ) = I ₀ × exp × (-(4 L × k × x )) . .. (hereinafter referred to as the first curve equation)

f ₂ ( x )= I ₀ × exp ×(-(1 L × k × x ))... (hereinafter referred to as the second curve equation)

In the above, in more detail, the first curve equation and the second curve equation satisfy the Beer-Lambert law, and the operation unit 51 can receive a first beam splitting energy and a first according to the first light sensing unit 31. A curve equation calculates a concentration of a first gas in the first sampling cavity 12, and the computing unit 51 can also calculate a second beam splitting energy received by the second light sensing unit 32 and a second curve equation. The concentration of a second gas in the second sampling chamber 13. By obtaining the slopes of the first curve equation and the second curve equation, it can be determined which of the first light sensing unit 31 or the second light sensing unit 32 can obtain a larger infrared energy change in the same concentration interval.

As shown in FIG. 12, for convenience of explanation, the following description will be first made using the concentration interval, and x1, x2, x3, and x4 in FIG. 12 represent different density values, respectively. For example, the concentration value x1 is 15,000 ppm (parts per million), the concentration value x2 is 20,000 ppm, the concentration value x3 is 30,000 ppm, and the concentration value x4 is 40,000 ppm. When the operation unit 51 calculates the concentration of the first gas measured by the first light sensing unit 31 and the concentration of the second gas measured by the second light sensing unit 32 is between the concentration values x1 and x2, The first light sensing can be determined by calculating a first tangent slope between the concentration values x1 and x2 of the first curve equation and calculating a second tangent slope between the concentration values x1 and x2 of the second curve equation. Which of the unit 31 or the second light sensing unit 32 can obtain a more accurate measurement.

In detail, when the concentration of the first gas and the concentration of the second gas are between the concentration values x1 and x2, the first curve equation has more infrared energy than the second curve equation. The change can resolve the concentration of the first gas having a concentration between the concentration values x1 and x2. In other words, when the change in infrared energy is large, it is easier to measure the correct concentration value. Thereby, it is more suitable to use the first sampling cavity 12 for measurement between the concentration values x1 and x2.

In addition, when the operation unit 51 calculates the concentration of the first gas measured by the first light sensing unit 31 and the concentration of the second gas measured by the second light sensing unit 32 is between the density values x3 and x4 The first light sensation can be determined by calculating a first tangent slope between the concentration values x3 and x4 of the first curve equation and calculating a second tangent slope between the concentration values x3 and x4 of the second curve equation. Which of the measuring unit 31 or the second light sensing unit 32 can obtain a more accurate measurement value. Further, as shown in FIG. 12, when the concentration of the first gas and the concentration of the second gas are between the concentration values x3 and x4, the first curve equation and the second curve equation are compared, the second curve equation There are more changes in the infrared energy that can resolve the concentration of the second gas having a concentration between the concentration values x3 and x4. Thereby, it is more suitable to use the second sampling chamber 13 for measurement between the concentration values x3 and x4.

From the above, as shown in FIG. 13, at a specific concentration value (x5 as shown in the figure), the first tangent slope of the first curve equation will be equal to the second tangent slope of the second curve equation. In other words, the concentration value (x5 as shown in the figure) will be a judgment value for judging whether the first sampling chamber 12 or the second sampling chamber 13 should be used. Thereby, the concentration value (x5 as shown in the figure) is a preset threshold, that is, in the case of the concentration value (x5 as shown in the figure), the first tangent slope and the second tangent slope are the same. . It should be noted that the preset threshold x5 will be described later in the fourth embodiment. In addition, the first tangent slope of the first curve equation and the second tangent slope of the second curve equation can be calculated by the differential method. After differentiation, the following relationship can be met:

Next, referring to FIG. 11 again, as shown in step S106, it is determined whether the absolute value of the first tangent slope is greater than the absolute value of the second tangent slope. In detail, by determining the first tangent slope of the first curve equation and the second tangent slope of the second curve equation, which of the first sampling cavity 12 and the second sampling cavity 13 can be determined The body is more suitable for measuring the current gas concentration.

Next, as shown in step S108, the concentration of the first gas is output. Specifically, when the absolute value of the first tangent slope is greater than the absolute value of the second tangent slope, the concentration of the first gas will be less than the preset threshold x5, and the operation unit 51 may output the concentration of the first gas to the display. On unit 52, to display the current concentration value of the first gas. In other words, it means that the currently measured gas is suitable for the measurement of the concentration using the first sampling chamber 12. It is worth noting that when the absolute value of the first tangent slope is equal to the absolute value of the second tangent slope, the concentration of the first gas can also be output.

Next, as shown in step S110, the concentration of the second gas is output. Specifically, when the absolute value of the first tangent slope is smaller than the absolute value of the second tangent slope, the concentration of the second gas is output. That is, when the absolute value of the first tangent slope is less than or equal to the absolute value of the second tangent slope, the concentration of the second gas will be greater than the preset threshold x5, and the arithmetic unit 51 may output the concentration of the second gas to the display unit. 52 to display the current concentration value of the second gas. In other words, it means that the currently measured gas is suitable for the measurement of the concentration using the second sampling chamber 13.

The method for measuring the gas concentration provided by the third embodiment of the present invention further includes the step S105 of calculating the first gas in the first sampling cavity 12, as shown in FIG. The concentration, and the concentration of the second gas in the second sampling chamber 13 are calculated. For example, according to the first light sensing unit 31 The received first beam splitting beam energy and a first curve equation calculate the concentration of the first gas in the first sampling chamber 12. At the same time, the concentration of the second gas in the second sampling cavity 13 can also be calculated according to the second beam splitting beam energy received by the second light sensing unit 32 and the second curve equation. Thereby, the concentration of the first gas in the first sampling chamber 12 or the concentration of the second gas in the second sample chamber 13 is selectively outputted onto the display unit 52.

It should be noted that although step S105 in FIG. 14 is after step S104, the present invention is not limited to the priority order of step S105 and step S104. In other words, step S105 may be in the step of calculating the first tangent slope and the second tangent slope, calculating the first tangent slope and the second tangent slope, or calculating the first tangent slope and the second tangent After the step of the slope. In other words, the progress of step S105 and step S104 may be independent of each other. In addition, the first sampling cavity 12, the second sampling cavity 13, the light-emitting module 2, the light sensing module 3, and the substrate module 5 provided by the third embodiment and the foregoing implementation are described. The example is similar and will not be repeated here.

Fourth embodiment

First, referring to FIG. 15 , a fourth embodiment of the present invention provides a gas concentration measuring method. As can be seen from a comparison between FIG. 15 and FIG. 14 , the fourth embodiment and the third embodiment have the greatest difference in that: the fourth embodiment The gas concentration measurement method is provided by directly determining whether the concentration of the first gas and the concentration of the second gas are greater than a predetermined threshold to determine the concentration of the first gas or the concentration of the second gas.

Referring to FIG. 13 and FIG. 15 simultaneously, the gas concentration measuring method provided by the fourth embodiment includes the following steps. As shown in step S202, a first beam splitting beam T1 is projected through a first sampling cavity 12 onto a first photo sensing unit 31, and a second sampling cavity 13 is provided to project through a second sampling cavity 13. The second beam splitting beam T2 on the second light sensing unit 32. It should be noted that step S202 is similar to step S102 described above, and details are not described herein again.

Next, as shown in step S204: calculating a first in the first sampling cavity 12 The concentration of the gas and the concentration of a second gas in the second sampling chamber 13 are calculated. In detail, the concentration of a first gas in the first sampling cavity 12 can be calculated according to the energy of a first beam splitting beam received by the first light sensing unit 31, and can be determined according to the second light sensing unit 32. The received second beam splitting beam energy calculates the concentration of a second gas in the second sampling chamber 13. Further, as described in the foregoing third embodiment, the concentration of the first gas may be calculated according to the first split beam energy and a first curve equation, and the concentration of the second gas may be based on the second split beam energy and A second curve equation is calculated, and the first curve equation and the second curve equation satisfy the Beer-Lambert law.

Next, as shown in step S206, it is determined whether the concentration of the first gas and the concentration of the second gas are greater than a predetermined threshold x5. In detail, the setting of the preset threshold x5 can be obtained from the first tangent slope and the second tangent slope mentioned in the third embodiment. In other words, the preset threshold x5 is a concentration of the second gas that satisfies the concentration of the first gas at or near (or close to the error value that can be omitted in the calculation), and satisfies the concentration of the first gas relative to the first curve equation. A first tangential slope is equal to or close to the second tangential slope of the second gas equation. For example, as shown in FIG. 13, at 23,000 ppm, the first tangential slope is equal to or close to the second tangential slope, whereby the preset threshold x5 may be 23,000 ppm, although the invention is not limited thereto. It should be noted that, in other embodiments, the first preset length L1 may be 3 centimeters (cm) to 6 centimeters for measuring carbon dioxide having a concentration value of 0 to 50,000 ppm, and the second preset length L2. It can be from 2 cm to 3 cm for carbon dioxide with a concentration value of 50,000 ppm or more. In other words, the preset threshold x5 can be changed by adjusting the first predetermined length L1 of the first sampling chamber 12 and the second preset length L2 of the second sampling chamber 13. Thereby, an environment in which the difference between the high and low concentrations of the gas is measured is large.

Next, as shown in step S208, the concentration of the second gas is output. In detail, when the concentration of the first gas and the concentration of the second gas are greater than a preset threshold x5, the concentration of the second gas is output. In other words, the absolute value of the first tangent slope is less than the first The absolute value of the second tangent slope, the second sampling chamber 13 is more suitable for measuring the current gas concentration, therefore, the operation unit 51 can output the concentration of the second gas to the display unit 52 to display the current concentration value of the second gas. .

Next, as shown in step S210, the concentration of the first gas is output. In detail, when the concentration of the first gas and the concentration of the second gas are less than a preset threshold or equal to the preset threshold, the concentration of the first gas is output. In other words, the absolute value of the slope of the first tangent is greater than the absolute value of the slope of the second tangent, and the first sampling chamber 12 is more suitable for measuring the current gas concentration. Therefore, the arithmetic unit 51 can output the first gas. The concentration is applied to the display unit 52 to display the current concentration value of the first gas.

Advantages of the embodiment

In summary, the present invention has the beneficial effects that the gas measuring device (Q, Q') and the gas concentration measuring method provided by the embodiments of the present invention utilize the technical features of the "splitting module 4" to make the light emitting module The generated projection beam T can be split by the beam splitting module 4 to form a first beam splitting beam T1 directed to the first photo sensing unit 31 and a second beam splitting beam T2 directed to the second photo sensing unit 32. Thereby, the first light sensing unit 31 can be used to measure the properties of the first gas, and the second light sensing unit 32 can be used to measure the properties of the second gas, and further, through the first light sensing unit 31 and the first The first light sensing unit 32 cooperates with the first beam splitting beam T1 and the second beam splitting beam T2 generated by the projection beam T, and can also be applied to an environment in which the difference between the high and low concentration of the gas is measured.

Thereby, the projected light beam T generated by the light-emitting module 2 forms at least two or more split light beams (the first split light beam T1 and the second split light beam T2) to respectively correspond to at least two light sensing units (first The light sensing unit 31 and the second light sensing unit 32). The plurality of split light beams (the first split light beam T1 and the second split light beam T2) formed by the same light emitting module 2 can make the gas concentration measurement value higher in accuracy and reduce the cost. In addition, when the size of the first sampling cavity 12 is larger than the size of the second sampling cavity 13, when the gas concentration to be measured is low, the first one with a longer size can be selected. In the sample cavity 12, when the gas concentration to be measured is high, the first sampling cavity 12 having a shorter size can be selected, and when the gas concentration to be measured is equal to or close to the preset threshold value x5, the first dimension is selected. A sampling chamber 12 (since the received infrared energy is large).

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Therefore, all equivalents of the present invention are included in the scope of the present invention.

Claims (15)

A gas measuring device includes: a cavity module, the cavity module includes a light guiding cavity, a first sampling cavity connected to the light guiding cavity, and a light connecting to the light guiding body a second sampling cavity of the cavity; a light emitting module, the light emitting module is disposed in the light guiding cavity, the light emitting module is configured to generate a projection beam; and a light sensing module is The light sensing module includes a first light sensing unit disposed in the first sampling cavity and a second light sensing unit disposed in the second sampling cavity; and a beam splitting module, The beam splitting module is disposed in the cavity module; wherein the projection beam generated by the light emitting module is split by the beam splitting module to form a first beam to the first light sensing unit a beam splitting beam and a second beam splitting beam directed to the second photo sensing unit. The gas measuring device of claim 1, wherein the size of the first sampling chamber and the size of the second sampling chamber are different from each other. The gas measuring device of claim 1, wherein the first photo sensing unit is adapted to measure a property of a first gas, and the second photo sensing unit is adapted to measure a property of a second gas, The first gas and the second gas are different from each other. The gas measuring device according to claim 1, wherein the light guiding cavity comprises a reflecting surface, the reflecting surface is a paraboloid, the parabolic mask has a focus, and the light emitting unit corresponds to the focus. The gas measuring device according to claim 1, wherein a length direction of the first sampling cavity and a longitudinal direction of the light guiding cavity are substantially perpendicular to each other, and a length direction of the second sampling cavity is The longitudinal direction of the light guiding cavity is substantially perpendicular to each other. The gas measuring device of claim 1, wherein the light guiding cavity has a light guiding space, the first sampling cavity has a first sampling space and a first receiving space, and the second The sampling cavity has a second sampling space and a second accommodating space, the first light sensing unit is disposed in the first accommodating space, and the second light sensing unit is disposed in the second In the accommodating space, the beam splitting module is disposed between the first sampling cavity and the second sampling cavity, and the beam splitting module includes a first beam splitting surface and a second beam splitting surface. The gas measuring device of claim 6, wherein the projected light beam comprises a first projected light beam projected onto the light guiding cavity and a second projected light beam, the first projected light beam passing through the light guiding light Reflecting the cavity to form a first reflected beam projected onto the first beam splitting surface of the beam splitting module, the first reflected beam passing through the reflection of the first beam splitting surface to form a projection to the The first beam splitting beam on the first light sensing unit, the second projection beam passing through the light guiding cavity to form a first projection surface projected to the second beam splitting surface of the beam splitting module a second reflected light beam, the second reflected light beam being reflected by the second light splitting surface to form the second split light beam projected onto the second light sensing unit. The gas measuring device according to claim 6, wherein the projected light beam includes a first incident light beam projected onto the first light splitting surface of the light splitting module and the first portion projected on the light splitting module a second incident beam of the dichroic surface, the first incident beam passing through the reflection of the first beam splitting surface to form the first beam splitting beam projected onto the first photo sensing unit, the first The two incident beams are reflected by the second beam splitting surface to form the second beam splitting beam projected onto the second photo sensing unit. The gas measuring device of claim 6, wherein the cavity module further comprises a third sampling cavity connected to the light guiding cavity and a fourth connected to the light guiding cavity a sampling chamber, the third sampling cavity has a third sampling space and a third receiving space, and the fourth sampling cavity has a fourth The light-splitting module further includes a third beam splitting surface and a fourth beam splitting surface, and the light sensing module further includes a third light sensing unit and a first The fourth light sensing unit is disposed in the third accommodating space, and the fourth light sensing unit is disposed in the fourth accommodating space. The gas measuring device of claim 1, wherein the light guiding cavity comprises a reflecting surface and an optical axis passing through a focus of the reflecting surface, and the beam splitting module has a first splitting light a central axis between the face and the second beam splitting surface, the central axis passing through the light guiding space, the optical axis and the central axis coincide with each other, or the optical axis and the central axis The two do not overlap each other. A gas concentration measuring method, the gas concentration measuring method comprising: providing a light emitting module, wherein the light emitting module generates a first splitting light beam that is projected through a first sampling cavity onto a first light sensing unit And the light emitting module generates a second split light beam that is projected through a second sampling cavity onto a second light sensing unit, wherein the size of the first sampling cavity is larger than the second sampling cavity a first gas in the first sampling cavity, a second gas in the second sampling cavity, and a first beam splitter received by the first light sensing unit a first tangential slope of the energy relative to a first curve equation, and a second tangential slope of the second beam splitting beam received by the second light sensing unit relative to a second curve equation; And determining whether an absolute value of the slope of the first tangent is greater than an absolute value of a slope of the second tangent; wherein, when an absolute value of the slope of the first tangent is greater than or equal to an absolute value of a slope of the second tangent Time The concentration of the first gas output; wherein, when the absolute value of the slope is less than the first tangent line tangent slope of the second absolute value, the output of the second gas concentration. The gas concentration measuring method of claim 11, further comprising: calculating the first sampling cavity according to the first beam splitting beam energy received by the first light sensing unit and the first curve equation Calculating the concentration of the first gas in the body, and calculating the number in the second sampling cavity according to the second beam splitting beam energy received by the second photo sensing unit and the second curve equation The concentration of the two gases. The method for measuring a gas concentration according to claim 11, wherein a projection beam generated by the illumination module passes through a splitting module to form the first split beam and the second split beam, The first curve equation and the second curve equation satisfy the Beer-Lambert law. A method for measuring a gas concentration, comprising: providing a light emitting module, wherein the light emitting module generates a first split light beam that is projected through a first sampling cavity onto a first light sensing unit, and the light emitting The module generates a second split beam that passes through a second sampling cavity to be projected onto a second photo sensing unit, wherein the size of the first sampling cavity is larger than the size of the second sampling cavity; Calculating a concentration of a first gas in the first sampling chamber by a first beam splitting energy received by the first light sensing unit, and a first received according to the second light sensing unit Dichotomizing the beam energy to calculate a concentration of a second gas in the second sampling chamber; and determining whether the concentration of the first gas and the concentration of the second gas are greater than a predetermined threshold; wherein, when When the concentration of the first gas and the concentration of the second gas are greater than the predetermined threshold, outputting the concentration of the second gas; wherein, the concentration of the first gas and the concentration of the second gas Less than the preset threshold Who is equal to the preset threshold, the output of the first gas concentration. The gas concentration measuring method according to claim 14, wherein the first gas The concentration is calculated according to the first beam splitting beam energy and a first curve equation, and the concentration of the second gas is calculated according to the second beam splitting beam energy and a second curve equation, the first curve The equation and the second curve equation satisfy the Beer-Lambert law, and the preset threshold value satisfies the concentration of the first gas equal to or close to the concentration of the second gas, and satisfies the concentration of the first gas A first tangential slope with respect to the first curve equation is equal to or close to a second tangential slope of the second gas.