Optical detection assembly

Abstract

This invention discloses an optical detection component, relating to the field of gas detection technology. The optical detection component is applied to a gas chamber structure, which has a gas cavity filled with gas. The optical detection component includes: a laser emitter disposed in the gas chamber structure, used to emit a laser beam into the gas cavity; a laser receiver disposed in the gas chamber structure and opposite to the laser emitter; and a lens module disposed between the laser emitter and the laser receiver, used to receive the laser beam emitted by the laser emitter and focus it towards the laser receiver. The incident light surface of the lens module and the emitting light surface of the laser emitter are inclined relative to each other, causing the laser light reflected from the incident light surface of the lens module to deviate from the laser emitter. The technical solution provided by this invention prevents the laser light from being reflected back to the laser emitter, improving the accuracy of the detection results and avoiding damage to the laser emitter.

Description

Technical Field

[0001] This invention relates to the field of detection technology, and in particular to an optical detection component. Background Technology

[0002] In the field of gas detection technology, the selective absorption characteristics of gas molecules to specific wavelengths of laser light are usually used to achieve highly sensitive detection of the concentration of target gas in the environment. If a certain gas is present in the environment, when the laser passes through the chamber or environment containing the gas, the gas molecules will absorb the laser photons that match its characteristic absorption spectrum, resulting in attenuation of the transmitted light intensity. The higher the gas concentration, the stronger the absorption and the more severe the light intensity attenuation. The attenuated light signal is then received by a laser receiver, and the laser intensity before and after gas absorption is compared to determine the gas concentration in the chamber or environment.

[0003] In existing structures, to ensure laser transmission from the transmitter to the receiver, a lens is typically used to focus the laser beam emitted by the laser transmitter onto the laser receiver. The incident light surface of the lens refracts and reflects the laser emitted by the laser transmitter. When the reflected light reaches the laser transmitter, it may cause problems such as higher-order modes, affecting the accuracy of gas concentration detection results. Over time, this can even burn the laser transmitter, affecting its lifespan.

[0004] Similarly, when detecting the concentration of dust and other microparticles in a gas, although the dust concentration is detected by dust scattering laser, the same instability problem mentioned above can be encountered, leading to inaccurate dust concentration detection results. Summary of the Invention

[0005] The main objective of this invention is to propose an optical detection component that addresses the technical problem of how the reflection of laser light from a lens onto a laser emitter affects the accuracy of gas concentration detection.

[0006] To achieve the above objectives, the present invention proposes an optical detection component applied to a gas chamber structure, wherein the gas chamber structure has a gas cavity filled with gas, and the optical detection component includes:

[0007] A laser emitter is disposed in the gas chamber structure, and the laser emitter is used to emit a laser beam toward the gas chamber;

[0008] A laser receiver is disposed in the gas chamber structure and is positioned opposite to the laser emitter;

[0009] A lens module is disposed between the laser emitter and the laser receiver. The lens module is used to receive the light beam emitted by the laser emitter and focus the light towards the laser receiver.

[0010] The incident light surface of the lens module and the emitting light surface of the laser emitter are inclined to each other, so that the laser reflected from the incident light surface of the lens module deviates from the laser emitter.

[0011] In one embodiment, the lens module includes:

[0012] A first lens is disposed close to the laser emitter, and the incident light surface of the first lens and the emitting light surface of the laser emitter are inclined relative to each other.

[0013] The second lens is disposed between the first lens and the laser receiver, and is positioned close to the laser receiver.

[0014] In one embodiment, the output surface of the laser emitter is not perpendicular to the optical axis of the beam focused by the lens module;

[0015] And / or, the detection surface of the laser receiver and the optical axis of the beam focused by the lens module are not perpendicular.

[0016] In one embodiment, when the output light surface of the laser emitter is not perpendicular to the optical axis of the beam focused by the lens module, at least one of the incident light surface and the output light surface of the first lens is a freeform surface.

[0017] And / or, when the detection light surface of the laser receiver and the optical axis of the beam focused by the lens module are not perpendicular, at least one of the incident light surface and the emitting light surface of the second lens is a freeform surface.

[0018] In one embodiment, the gas chamber includes a first substrate having a first mounting surface facing the laser emitter. The first mounting surface is inclined, and the light emission surface of the laser emitter is parallel to the first mounting surface, such that the light emission surface of the laser emitter is not perpendicular to the optical axis direction of the light beam collimated by the first lens.

[0019] And / or, the gas chamber includes a second substrate having a second mounting surface facing the laser receiver, the second mounting surface being inclined, and the detection surface of the laser receiver being parallel to the second mounting surface, such that the detection surface of the laser receiver and the optical axis direction of the beam collimated by the first lens are not perpendicular.

[0020] In one embodiment, the first lens includes an optical section for light processing. The emitting surface of the laser emitter is perpendicular to the optical axis of the beam focused by the lens module. One end of the optical section is inclined, and the curvature of the emitting surface of the optical section away from the laser emitter is greater than the curvature of the end closer to the laser emitter.

[0021] In one embodiment, the divergence angle of the laser emitted by the laser emitter is set to 2α degrees, and one end of the optical part is tilted so that the incident light surface of the optical part is tilted relative to the laser emitter, forming a tilt angle of β degrees, and there is a relationship of β > α between the tilt angle and the divergence angle of the laser emitted by the laser emitter.

[0022] In one embodiment, the receiving full angle of the second lens is greater than or equal to the diverging full angle of the first lens.

[0023] In one embodiment, the inner wall of the air chamber structure is provided with a light-absorbing coating;

[0024] And / or, the inner wall of the air chamber structure is made of black resin or a black film layer.

[0025] In one embodiment, the inner wall of the air chamber structure is provided with a serrated structure.

[0026] In the technical solution of this invention, a laser emitter and a laser receiver are respectively arranged on opposite sides of the inner wall of the gas chamber. A first lens is arranged between the laser emitter and the laser receiver, with the first lens positioned close to the laser emitter. The laser emitter emits a laser beam directionally toward the interior of the gas chamber. The incident light surface of the first lens is close to the laser emitter and receives all the laser beam emitted by the laser emitter, converting the divergent laser beam into a focused beam for emission toward the laser receiver. By analyzing the light intensity received by the laser receiver and the laser intensity emitted by the laser emitter, the gas concentration is calculated using the Beer-Lambert law. Furthermore, the incident light surface of the first lens and the emission light surface of the laser emitter are inclined relative to each other, so that when the laser emitter emits laser toward the first lens, the laser reflected from the incident light surface of the first lens deviates from the laser emitter, thereby preventing the laser from being reflected back to the laser emitter. This avoids burning the laser emitter, increases the service life of the device, and also avoids affecting the laser emitted by the laser emitter, improving the accuracy of the laser detection results. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of the first embodiment of the optical detection component provided by the present invention;

[0029] Figure 2 This is a schematic diagram of the structure of the second embodiment of the optical detection component provided by the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of the third embodiment of the optical detection component provided by the present invention;

[0031] Figure 4 This is a schematic diagram of the structure of the fourth embodiment of the optical detection component provided by the present invention;

[0032] Figure 5 This is a schematic diagram of the structure of the fifth embodiment of the optical detection component provided by the present invention;

[0033] Figure 6 This is a schematic diagram of the structure of the sixth embodiment of the optical detection component provided by the present invention;

[0034] Figure 7 A schematic diagram showing the relationship between the tilt angle of the first lens and the divergence angle of the laser emitter in the optical detection assembly provided by the present invention;

[0035] Figure 8 This is a schematic diagram of the structure of the first lens in the optical detection assembly provided by the present invention.

[0036] Explanation of icon numbers:

[0037] 10. Air chamber; 101. Air cavity; 11. First substrate; 12. Second substrate;

[0038] 20. Data processing module;

[0039] 100. Laser emitter;

[0040] 200, Lens module; 210, First lens; 211, Connecting part; 212, Optical part; 220, Second lens;

[0041] 300. Laser receiver.

[0042] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0043] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0044] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0045] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0046] In the field of gas detection technology, the selective absorption characteristics of gas molecules to specific wavelengths of laser light are usually used to achieve highly sensitive detection of the concentration of target gas in the environment. If a certain gas is present in the environment, when the laser passes through the chamber or environment containing the gas, the gas molecules will absorb the laser photons that match its characteristic absorption spectrum, resulting in attenuation of the transmitted light intensity. The higher the gas concentration, the stronger the absorption and the more severe the light intensity attenuation. The attenuated light signal is then received by a laser receiver, and the laser intensity before and after gas absorption is compared to determine the gas concentration in the chamber or environment.

[0047] In existing structures, to ensure that the laser is transmitted from the transmitter to the receiver, a lens is generally used to focus the laser beam emitted by the laser transmitter onto the laser receiver. The incident light surface of the lens refracts and reflects the received laser at the same time. When the reflected light is reflected back to the laser transmitter, it will cause problems such as higher-order modes, resulting in lasers of other frequencies or wavelengths, which will affect the accuracy of gas concentration detection results. In fact, if this continues for a long time, it will burn the laser transmitter and affect its service life.

[0048] Similarly, when detecting the concentration of dust and other microparticles in a gas, although the dust concentration is detected by dust scattering laser, the same instability problem mentioned above can be encountered, leading to inaccurate dust concentration detection results.

[0049] This invention proposes an optical detection component.

[0050] Please see Figure 1 and Figure 2 In one embodiment of the present invention, the optical detection component is applied to a gas chamber 10 structure, the gas chamber 10 structure having a gas cavity 101 filled with gas, and the optical detection component includes:

[0051] A laser emitter 100 is disposed in the gas chamber 10 structure, and the laser emitter 100 is used to emit a laser beam toward the gas chamber 101;

[0052] A laser receiver 300 is located in the gas chamber 10 structure and is positioned opposite to the laser emitter 100.

[0053] The lens module 200 is disposed between the laser emitter 100 and the laser receiver 300. The lens module 200 is used to receive the light beam emitted by the laser emitter 100 and focus the light towards the laser receiver 300.

[0054] The incident light surface of the lens module 200 and the emitting light surface of the laser emitter 100 are inclined to each other, so that the laser reflected from the incident light surface of the lens module 200 deviates from the laser emitter 100.

[0055] In the technical solution of this invention, a laser emitter 100 and a laser receiver 300 are respectively arranged on opposite sides of the inner wall of the gas chamber 10. A lens module 200 is arranged between the laser emitter 100 and the laser receiver 300, with the lens module 200 positioned close to the laser emitter 100. The laser emitter 100 emits a laser beam directionally toward the interior of the gas chamber 10. The incident light surface of the lens module 200 is close to the laser emitter 100 and receives all the laser beam emitted by the laser emitter 100, focusing the laser beam toward the laser receiver 300. The light intensity received by the laser receiver 300 is analyzed. The gas concentration is calculated using the Beer-Lambert law based on the laser intensity emitted by the laser emitter 100. Furthermore, the incident light surface of the lens module 200 and the emitting light surface of the laser emitter 100 are tilted relative to each other. This ensures that when the laser emitter 100 emits laser light towards the lens module 200, the laser light reflected from the incident light surface of the lens module 200 deviates from the laser emitter 100, thus preventing the laser light from being reflected back to the laser emitter 100. This avoids burning the laser emitter 100, extends the lifespan of the device, and also prevents problems such as higher-order modes affecting the laser light emitted by the laser emitter 100, thereby improving the accuracy of laser detection results.

[0056] The solution proposed in this application is not limited to detecting gas concentration, but can also be used to detect the concentration of microparticles in gas. When microparticles are scattered in the gas chamber 10, a laser emitter 100 emits a beam of light into the gas chamber 10. The beam hits the microparticles and scatters the light. The intensity of the scattered light is detected by the laser receiver 300 to judge the particle concentration. It should be noted that if the concentration of microparticles is being detected, since the microparticles scatter the light beam in all directions, the laser receiver 300 is not placed in a position opposite to the laser emitter 100, but is placed on the upper or lower wall of the gas chamber 10 as shown in the figure. This will not be described in detail here.

[0057] In this embodiment, the lens module 200 is disposed within the air cavity 101 and adjacent to the emitting surface of the laser emitter 100. It receives the laser beam emitted by the laser emitter 100 and converts the laser beam into a focused beam. The optical axis of the focused beam can be horizontal, vertical, or tilted, without limitation, as long as the emitted direction can be received by the laser receiver 300. The lens module 200 can be an aspherical lens. In particular, when the lens module 200 and the laser emitter 100 are tilted relative to each other in this embodiment, the lens module 200 can be a freeform surface. Through the reasonable design of the freeform surface, the focused beam can be better received by the laser receiver 300.

[0058] Specifically, a gas chamber 101 is formed inside the gas chamber 10 structure. The gas chamber 10 can be rectangular, cylindrical, or spherical, without limitation. The gas chamber 101 can be closed or semi-closed. If it is semi-closed, an air inlet and an air outlet are provided on one side of the gas chamber 10, which can realize dynamic gas renewal or continuous sampling. The gas in the gas chamber 101 can be one or more of methane, ethane, propane, acetylene, or carbon monoxide, without limitation. Different gases absorb different laser wavelengths. For example, methane mainly absorbs laser wavelengths around 1650nm. Preferably, 101 is the most suitable gas for this purpose. For detecting methane, the laser emitter 100 emits a 1653nm laser. Similarly, ethane mainly absorbs lasers with wavelengths of 1682nm-1684nm, preferably 1683nm. Therefore, when detecting ethane concentration, the laser emitter 100 emits a 1683nm laser. Propane mainly absorbs lasers with wavelengths of 1500nm-1700nm, preferably 1690nm. Carbon monoxide mainly absorbs lasers with wavelengths of 1567nm, 2.3μm, and 4.6μm. These will not be described in detail here.

[0059] The laser emitter 100 can be any one of a DFB (tunable semiconductor laser), an ICL (interband cascaded laser), an FP-LD, or a QCL (quantum cascaded laser), without limitation. The laser emitter 100 is positioned on one side within the gas cavity 101 and emits a laser of a specific wavelength with a certain divergence angle towards the interior of the gas cavity 101. The divergence angle is not limited here, but is typically 5°-15°. DFB lasers are generally used for the detection of gases such as methane, ethane, and carbon monoxide. ICL lasers operate in the 3-6 μm band and are suitable for the detection of propane, acetylene, and some hydrocarbons. FP-LD lasers can be used for preliminary screening with low precision, or for wavelength selection in conjunction with filters or gratings. QCL lasers operate in the 4-12 μm band, exhibiting high absorption intensity and high detection sensitivity. In one embodiment, different laser emitters 100 can be used to emit light signals of at least one wavelength, with different wavelengths used to detect different gas components in the gas.

[0060] The laser receiver 300 is positioned opposite the laser emitter 100 and can employ a high-sensitivity photodetector such as an InGaAs PIN photodiode or an avalanche photodiode (APD), with no particular limitation. Preferably, the detection surface of the laser receiver 300 is provided with an anti-reflection coating to reduce the reflection of the converged beam.

[0061] The gas concentration is calculated from the laser intensity emitted by laser emitter 100 and the laser intensity received by laser receiver 300. This can be done manually or using data processing module 20. Data processing module 20 is communicatively connected to both laser emitter 100 and laser receiver 300, receiving data from both and calculating the concentration using Beer-Lambert's law. .

[0062] Where, I0: the intensity of the incident laser;

[0063] I: The intensity of the projected laser is the same as the intensity received by the laser receiver 300;

[0064] α(ν): Absorption coefficient of gas at laser frequency ν (or wavelength λ) (unit: cm) - ¹·ppm - ¹ or cm² / molecule);

[0065] c: Gas concentration (unit: ppm, %vol or molecule / cm³);

[0066] L: Effective optical path length (the path length of the laser beam through the gas cavity 101, in cm or m)

[0067] That is, based on I0 and I, and the known α(ν) and L, the gas concentration c is obtained. .

[0068] In one embodiment, the lens module 200 may include only a focusing lens. The incident light surface of the focusing lens is close to the laser emitter 100 and receives all the light beam emitted by the laser emitter 100, focusing the laser beam towards the laser receiver 300. When the lens module 200 uses a focusing lens, it includes an integrally formed optical assembly and a connecting assembly. The connecting assembly is used to fix the optical assembly in the gas chamber 10. The optical assembly is opposite to the laser emitter 100 and is used to receive the light emitted by the laser emitter 100. It should be noted that the cross-sectional dimension of the optical assembly is larger than the divergence angle of the laser emitter 100 to receive all the light emitted by the laser emitter 100 and avoid light loss. The connecting assembly is made of high-strength, corrosion-resistant material to ensure stable fixation of the optical assembly in the complex environment of the gas chamber 10 and to ensure the normal operation of the optical detection component.

[0069] like Figure 1 As shown, the focusing lens rotates, causing the incident light surface of the optical group of the focusing lens to tilt relative to the laser emitter 100. (The text then repeats itself.) Figure 2As shown, the laser emitter 100 is tilted so that its incident light surface is tilted relative to the optical group of the focusing lens, and the tilting method of the focusing lens is not restricted.

[0070] It should be noted that the lens module 200 uses a focusing lens. When the focusing lens receives the light beam emitted by the laser emitter 100 and reflects it toward the laser receiver 300, the emitted light is the focused light. In the path of the emitted light, there is a position where the light beam is focused into a point. The distance between the laser receiver 300 and the lens module 200 must be greater than the distance between the reflecting surface of the focusing lens and the focusing point to avoid the reflected light from burning the laser receiver 300.

[0071] Please refer to Figure 3 In an embodiment of the present invention, the lens module 200 includes:

[0072] A first lens 210 is disposed close to the laser emitter 100, and the incident light surface of the first lens 210 and the emitting light surface of the laser emitter 100 are inclined to each other.

[0073] The second lens 220 is disposed between the first lens 210 and the laser receiver 300, and is positioned close to the laser receiver 300.

[0074] Specifically, the first lens 210 is configured as a collimating lens. The collimating lens receives the diverging laser beam emitted by the laser emitter 100 and is used to focus the diverging laser beam into a collimated beam. This allows it to focus a diverging beam with a large divergence angle emitted by the laser emitter 100 into a parallel beam with a smaller divergence angle. It should be noted that, for example... Figure 3 and Figure 8 As shown, the first lens 210 has an integrally formed optical part 212 and a connecting part 211. The connecting part 211 is used to fix the optical part 212 in the air chamber 10. The optical part 212 is used to process light, that is, to receive the light emitted by the laser emitter 100 and refract the light towards the laser receiver 300. The optical part 212 has an incident light surface facing the laser emitter 100 and an exit light surface facing the laser receiver 300. The incident light surface of the optical part 212 of the first lens 210 and the exit light surface of the laser emitter 100 are inclined to each other, so that when the incident light surface of the first lens 210 reflects the light beam, the reflected light beam can deviate from the laser emitter 100, thereby avoiding burning the laser emitter 100 and avoiding affecting the detection accuracy. The second lens 220 is configured as a focusing lens to converge the collimated parallel beam onto the detection surface of the laser receiver 300. The focusing lens can be a plano-convex lens or a biconvex lens, and its focal length and light receiving angle need to be selected according to the beam diameter to ensure that the parallel beam can be effectively converged onto the laser receiver 300.

[0075] In one embodiment, the reflecting surface of the second lens 220 and the detecting surface of the laser receiver 300 are inclined relative to each other, such as... Figure 4 As shown, when the reflective surface of the second lens 220 is tilted relative to the detection surface of the laser receiver 300, most of the laser reflected from the detection surface of the laser receiver 300 will not return to the laser emitter 100 along the opposite path of the incident laser. This can further avoid affecting the detection results, improve the accuracy of the detection results, and also extend the service life of the equipment.

[0076] It should be noted that the second lens 220 is the same as the first lens 210, and also includes optical components and connecting components. The optical components are used to receive the light emitted by the optical part 212 of the first lens 210 and refract it towards the laser receiver 300. The connecting components are used to install the optical components on the inner wall of the gas chamber 10. Since the first lens 210 is closer to the laser emitter 100, the light reflected by the second lens 220 will not directly affect the laser emitter 100. Therefore, the structure of the second lens 220 will not be described in detail, and the second lens 220 is only represented by the optical components.

[0077] In an embodiment of the present invention, the emitting surface of the laser emitter 100 is not perpendicular to the optical axis of the beam focused by the lens module 200. If the beam focused by the first lens 210 is emitted with its optical axis oriented horizontally, the emitting surface of the laser emitter 100 is tilted, which can achieve the following: Figure 5 As shown, the mounting base of the laser emitter 100 is set to be inclined relative to the optical axis direction. Alternatively, the mounting base can be perpendicular to the optical axis direction, while the laser emitter 100 itself is installed at an angle, making it inclined relative to the horizontal direction (not shown). No restriction is imposed here.

[0078] In one embodiment, such as Figure 5 As shown, the output light surface of the laser emitter 100 is tilted, and at least one of the incident light surface and the output light surface of the first lens 210 is a freeform surface. This ensures that the laser light reflected from the incident light surface and the output light surface of the first lens 210 will not be reflected back to the laser emitter 100. By adjusting the curvature of the output light surface of the first lens 210, the output laser light can not only be completely received by the laser receiver 300, but its optical axis direction can also be horizontal. Specifically, simulation and debugging can be performed using simulation software such as ZEMAX and LightTools to obtain suitable curvatures for the incident light surface and the output light surface of the first lens 210.

[0079] In one embodiment, the gas chamber 10 includes a first substrate 11, the first substrate 11 having a first mounting surface facing the laser emitter 100, the first mounting surface being inclined, and the light emitting surface of the laser emitter 100 being parallel to the first mounting surface, such that the light emitting surface of the laser emitter 100 is not perpendicular to the optical axis direction of the light beam after being focused and collimated by the first lens 210.

[0080] Specifically, the first substrate 11 serves as the mounting base surface for the laser emitter 100. The first substrate 11 has a first mounting surface facing into the gas cavity 101. The first mounting surface is inclined in the vertical direction, thereby causing the laser emitter 100 on the first mounting surface to be inclined, such as... Figure 5 As shown, the distance between the upper end of the first mounting surface and the laser receiver 300 is greater than the distance between the lower end of the first mounting surface and the laser receiver 300. That is, the entire first mounting surface is tilted upward, which means that the light emitting surface of the first mounting surface is tilted upward. The first lens 210 can be a plano-convex mirror or a biconvex mirror, preferably a biconvex mirror. The incident light surface and the exit light surface of the first lens 210 are preferably free-form surfaces, which can prevent the incident light surface of the first lens 210 from reflecting the laser to the laser emitter 100 and affecting the emission of the laser emitter 100.

[0081] In another embodiment, the tilt direction of the first mounting surface can also be opposite, such as the distance between the upper end of the first mounting surface and the laser receiver 300 being less than the distance between the lower end of the first mounting surface and the laser receiver 300. Correspondingly, the first lens 210 is preferably a biconvex lens with a free-form surface.

[0082] In some embodiments, the detection surface of the laser receiver 300 and the optical axis of the beam collimated by the first lens 210 are not perpendicular, such as... Figure 6 As shown, if the optical axis of the collimated parallel beam is horizontal, the detection surface of the laser receiver 300 can be tilted. This can be configured such that the mounting base of the laser receiver 300 is tilted relative to the optical axis, or the mounting base is perpendicular to the optical axis, while the laser receiver 300 itself is tilted relative to the horizontal direction. No restrictions are imposed here.

[0083] In one embodiment, such as Figure 6 As shown, the detection surface of the laser receiver 300 is tilted, and at least one of the incident light surface and the emitting light surface of the second lens 220 is a freeform surface (not shown in the figure). The curvature of the surface can be simulated and adjusted according to the computer ZEMAX or LightTools, so that the second lens 220 can completely receive the parallel beam and emit the focused beam to the laser receiver 300. This can prevent the laser from being reflected back to the laser emitter 100 and ensure that the focused laser can be received by the laser receiver 300.

[0084] In one embodiment, the gas chamber 10 includes a second substrate 12, the second substrate 12 having a second mounting surface facing the laser receiver 300, the second mounting surface being inclined, and the detection light surface of the laser receiver 300 being parallel to the second mounting surface, such that the detection light surface of the laser receiver 300 and the optical axis direction of the beam collimated by the first lens 210 are not perpendicular.

[0085] Specifically, the second substrate 12 serves as the mounting base surface of the laser receiver 300, having a second mounting surface facing into the gas cavity 101, and the second substrate 12 is disposed opposite to the first substrate 11, such as... Figure 6 As shown, the second mounting surface is inclined, and the distance between the upper end of the second mounting surface and the laser emitter 100 can be set to be greater than the distance between the lower end of the second mounting surface and the laser emitter 100, as long as the receiving point of the laser receiver 300 is located at the focusing center of the second lens 220. The second lens 220 can be a biconvex lens or a plano-convex mirror, and preferably a biconvex mirror. The incident light surface and the emitted light surface of the second lens 220 are set as free-form surfaces to prevent the laser from being reflected to the laser emitter 100. The curvature can also be adjusted so that the laser can be focused onto the laser receiver 300 and thus be received by the laser receiver 300.

[0086] In one embodiment, such as Figure 3 and Figure 5 As shown, the detection surface of the laser receiver 300 is perpendicular to the optical axis of the focused and collimated beam. At this time, the detection surface of the laser receiver 300 and the emission surface of the second lens 220 are not tilted. Preferably, the incident surface and the emission surface of the second lens 220 are set as free-form surfaces to avoid the laser being reflected back to the laser emitter 100.

[0087] In one embodiment, the detection surface of the laser receiver 300 is perpendicular to the optical axis of the collimated beam, and one end of the second lens 220 is relatively tilted. The upper end can be tilted away from the laser receiver 300, or it can be as follows: Figure 4 As shown, the lower end of the laser receiver 300 is tilted away from the laser receiver 300, which also prevents the laser reflected by the laser receiver 300 from being reflected back to the laser emitter 100.

[0088] In the above embodiment, the second substrate 12 can be configured to be perpendicular to the optical axis direction, and the detection surface of the laser receiver 300 can be parallel to the second mounting surface, so that the detection surface of the laser receiver 300 is perpendicular to the optical axis direction.

[0089] In an embodiment of the present invention, the emitting surface of the laser emitter 100 is perpendicular to the optical axis of the beam collimated by the first lens 210. One end of the optical section 212 is inclined, and the curvature of the end of the emitting surface of the optical section 212 away from the laser emitter 100 is greater than the curvature of the end closer to the laser emitter 100. This design facilitates the first lens 210 in tilting the beam towards the side with greater curvature, resulting in a more focused beam that is more easily received by the laser receiver 300. Figure 1 , Figure 3 , Figure 4 and Figure 6 As shown, the first substrate 11 is perpendicular to the optical axis, which makes the laser emitter 100 on the first mounting surface perpendicular to the optical axis. One end of the optical part 212 is tilted, so that the incident light surface of the optical part 212 is tilted relative to the laser emitter 100. It can be understood that the normal of any point on the incident light surface of the optical part 212 is not perpendicular to the emitting light surface of the laser emitter 100. That is, when the laser emitter 100 emits laser light toward the first lens 210, all the light reflected by the first lens 210 deviates from the laser emitter 100.

[0090] In one embodiment, such as Figure 1 , Figure 3 , Figure 4 and Figure 6 As shown, the lower end of the optical section 212 is tilted away from the laser emitter 100. The laser reflected from the incident light surface of the first lens 210 is reflected to the lower left. By adjusting the tilt angle of the first lens 210, when the uppermost tilted beam emitted by the laser emitter 100 reaches the first lens 210 and is reflected, the reflected laser is directed towards the lower end of the laser emitter 100. This ensures that all lasers emitted from the incident light surface of the first lens 210 and reflected can be reflected to the lower part of the laser emitter 100.

[0091] In one embodiment, the upper end of the optical unit 212 is tilted away from the laser emitter 100 (not shown in the figure), that is, the lower end of the optical unit 212 is closer to the laser emitter 100 than the upper end. At this time, it is necessary to adjust the angle so that when the laser emitted from the lowermost end of the laser emitter 100 is emitted to the incident light surface of the first lens 210, the reflected laser is reflected to the upper end of the laser emitter 100, which can ensure that all lasers reflected from the incident light surface of the first lens 210 are deviated from the laser emitter 100.

[0092] Correspondingly, if the emitting surface of the first lens 210 is a symmetrical convex surface, it will cause the parallel beam to tilt, which is not conducive to the reception of the second lens 220. Therefore, by adjusting the curvature of the emitting surface of the optical unit 212, the collimated parallel beam is made to be horizontally oriented towards the second lens 220. Figure 3 , Figure 4 and Figure 6 When the lower end of the optical section 212 is tilted away from the laser emitter 100, the curvature of the lower end of the light-emitting surface of the optical section 212 is set to be greater than the curvature of the upper end. In another embodiment, when the upper end of the optical section 212 is tilted away from the laser emitter 100, the curvature of the upper end of the light-emitting surface of the optical section 212 is set to be greater than the curvature of the lower end. This design will help the first lens 210 to tilt the light beam towards the side with greater curvature, making the light beam more focused and easier for the laser receiver 300 to receive. The specific curvature value is related to the tilt angle of the first lens 210 and can be obtained through simulation using ZEMAX or LightTools software, which will not be described in detail here.

[0093] like Figure 7 As shown, the divergence angle of the laser emitted by the laser emitter 100 is 2α degrees, that is, its half-angle is α degrees. Therefore, one end of the optical section 212 is tilted, causing the incident light surface of the optical section 212 to be tilted relative to the laser emitter 100, forming a tilt angle of β degrees. At least β > α is required to ensure that all the light reflected by the first lens 210 deviates from the laser emitter 100, i.e., as shown... Figure 7 As shown, the light from the top also reflects towards the bottom of the laser emitter 100.

[0094] In an embodiment of the present invention, the receiving full angle of the second lens 220 is greater than or equal to the diverging full angle of the first lens 210. That is, the receiving full angle of the second lens 220 is greater than the distance between the two ends of the collimated beam. This ensures that the collimated beam transmitted through the air cavity 101 can be completely captured by the second lens 220 and focused onto the detection surface of the laser receiver 300, avoiding light energy loss and preventing low or unstable concentration measurements. The receiving full angle of the second lens 220 is determined by its focal length f and aperture D, and is twice the receiving half angle. Furthermore, the focal length of the second lens 220 is optimized through simulation using ZEMAX or LightTools so that its focal point falls on the center of the photosensitive area of ​​the laser receiver 300, thereby improving the accuracy of concentration calculation.

[0095] In an embodiment of the present invention, the inner wall of the gas chamber 10 structure is provided with a light-absorbing coating, which can absorb the laser reflected onto the inner wall, preventing the reflected laser from being reflected multiple times on the inner wall of the gas chamber 10 before entering the laser emitter 100 or the laser receiver 300 and affecting normal detection, thereby improving the accuracy of gas concentration detection.

[0096] In one embodiment, the inner wall of the air chamber 10 structure is made of black resin or a black film layer, which has good light absorption performance and low cost.

[0097] In other embodiments, the inner wall of the gas chamber 10 may also be coated with a carbon nanotube coating, which has ultra-black properties and can achieve a laser absorption rate of over 99% in a wide wavelength range. This is not a limitation.

[0098] It should be noted that when selecting a light-absorbing coating, the absorption efficiency of the coating material at the target laser wavelength and its chemical stability under the gas to be measured should be considered to reduce the impact on gas concentration detection.

[0099] In an embodiment of the present invention, the inner wall of the gas chamber 10 is provided with a serrated structure. The serrated structure can increase the surface area of ​​the inner wall of the gas chamber 10, improve the absorption rate of the laser reflected onto the inner wall, avoid affecting normal detection, reduce the impact on gas concentration detection, and make the gas concentration calculation more accurate.

[0100] In one embodiment, the sawtooth structure can be configured as a concave-convex structure or as a continuously arranged arc-shaped groove. There are no restrictions on this, as long as it can increase the surface area of ​​the inner wall of the air chamber 10.

[0101] The above description is merely an exemplary embodiment of the present invention and does not limit the scope of protection of the present invention. Any equivalent structural transformations made based on the technical concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. An optical detection component applied to a gas chamber structure, the gas chamber structure having a gas cavity filled with gas, characterized in that, The optical detection component includes: A laser emitter is disposed in the gas chamber structure, and the laser emitter is used to emit a laser beam toward the gas chamber; A laser receiver is disposed in the gas chamber structure and is positioned opposite to the laser emitter; A lens module is disposed between the laser emitter and the laser receiver. The lens module is used to receive the light beam emitted by the laser emitter and focus the light towards the laser receiver. The lens module includes a first lens disposed close to the laser emitter. The first lens includes an optical section for light processing. The optical section has an incident light surface facing the laser emitter and an emitting light surface facing the laser receiver. The incident light surface of the optical section and the emitting light surface of the laser emitter are inclined to each other, such that the laser reflected from the incident light surface of the first lens deviates from the laser emitter. The laser emitter's emitting surface is perpendicular to the optical axis of the beam focused by the lens module. One end of the optical component is tilted, and the curvature of the emitting surface of the optical component away from the laser emitter is greater than the curvature of the emitting surface. The divergence angle of the laser emitted by the laser emitter is set to 2α degrees, and the incident surface of the optical component is tilted relative to the emitting surface of the laser emitter to form a tilt angle of β degrees. The relationship between this tilt angle and the divergence angle of the laser emitted by the laser emitter is β > α.

2. The optical detection component as described in claim 1, characterized in that, The lens module includes: The second lens is disposed between the first lens and the laser receiver, and is positioned close to the laser receiver.

3. The optical detection component as described in claim 2, characterized in that, The detection surface of the laser receiver and the optical axis of the beam focused by the lens module are not perpendicular.

4. The optical detection component as described in claim 3, characterized in that, At least one of the incident light surface and the emitted light surface of the second lens is a freeform surface.

5. The optical detection component as described in claim 4, characterized in that, The gas chamber includes a second substrate, the second substrate having a second mounting surface facing the laser receiver, the second mounting surface being inclined, and the detection light surface of the laser receiver being parallel to the second mounting surface, such that the detection light surface of the laser receiver and the optical axis direction of the beam collimated by the first lens are not perpendicular.

6. The optical detection component as described in any one of claims 2-5, characterized in that, The receiving angle of the second lens is greater than or equal to the diverging angle of the first lens.

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