A laser detection instrument capable of detecting ammonia

Abstract

The utility model discloses a kind of laser detection instruments capable of measuring ammonia, it is related to gas detection technical field, including laser, optical spectrometer, detection gas chamber, detection module and control processing unit, laser is used to emit wavelength range as 1512.2-1512.3nm laser in optical path direction;Optical spectrometer is located in one side of laser along optical path direction, optical spectrometer light inlet is connected with laser light outlet, and it is used to divide laser into two different road measurement light and reference light;Detection gas chamber is located in one side of optical spectrometer away from laser, detection gas chamber light inlet is connected with the measurement light light outlet of optical spectrometer, and detection gas chamber is equipped with air inlet and air outlet;Detection module includes first detection unit and second detection unit, first detection unit light inlet is connected with the light outlet of detection gas chamber, and second detection unit light inlet is connected with the reference light light outlet of optical spectrometer.The technical scheme provided by the utility model solves the problem of low detection precision of existing detector.

Description

Technical Field

[0001] This utility model relates to the field of gas detection technology, and in particular to a laser detection instrument capable of detecting ammonia. Background Technology

[0002] The Importance of Ammonia Detection: In industrial production and environmental monitoring, the accurate detection of ammonia concentration, as an important chemical substance, is crucial for ensuring production safety, improving product quality, and protecting the environment. Excessive ammonia concentration not only affects the stability of the production process but may also pose hazards to human health and the environment.

[0003] Currently, most ammonia detection instruments on the market are based on the laser detection principle, which to some extent meets the needs of ammonia concentration detection. However, traditional ammonia laser detectors typically use a single measuring light for detection, which can lead to low detection accuracy. Utility Model Content

[0004] The main purpose of this invention is to propose a laser detection instrument for measuring ammonia, aiming to solve the problem of low detection accuracy in existing detectors.

[0005] To achieve the above objectives, this utility model proposes a laser detection instrument for measuring ammonia, comprising: A laser used to emit laser light with a wavelength range of 1512.2-1512.3 nm in the direction of the optical path; A beam splitter is disposed on one side of the laser along the optical path direction. The light inlet of the beam splitter is connected to the light outlet of the laser, and is used to split the laser into two different paths: a measurement beam and a reference beam. A detection gas chamber is located on the side of the beam splitter opposite to the laser. The light inlet of the detection gas chamber is connected to the measurement light outlet of the beam splitter. The detection gas chamber has an inlet and an outlet, which are used for the entry and exit of the gas to be measured, respectively. The detection module includes a first detection unit and a second detection unit. The light inlet of the first detection unit is connected to the light outlet of the detection chamber to convert the optical signal of the measurement light into an electrical signal. The light inlet of the second detection unit is connected to the reference light outlet of the beam splitter to convert the optical signal of the reference light into an electrical signal. The control processing unit is electrically connected to both the first detection unit and the second detection unit to convert the electrical signals detected by the first detection unit and the second detection unit into ammonia concentration values.

[0006] In one embodiment, the laser detection instrument for measuring ammonia further includes a reflector, which is disposed at the light outlet of the detection chamber, and the light outlet of the detection chamber is connected to the light inlet of the reflector via a light beam, and the light outlet of the reflector is connected to the light inlet of the first detection unit via a light beam.

[0007] In one embodiment, the reflector is a concave mirror.

[0008] In one embodiment, the laser detection instrument for measuring ammonia further includes a collimating lens, which is disposed between the laser and the beam splitter along the optical path direction. The light inlet and light outlet of the collimating lens are respectively connected to the light outlet of the laser and the light inlet of the beam splitter. The collimating lens is used to collimate the laser emitted by the laser into a parallel beam.

[0009] In one embodiment, the central axis of the laser and the central axis of the beam splitter both coincide with the central axis of the collimating lens.

[0010] In one embodiment, the air inlet and the air outlet are disposed opposite to each other on the upper and lower sides of the optical path direction.

[0011] In one embodiment, both the first detection unit and the second detection unit are photodetectors.

[0012] In one embodiment, the laser is a tunable semiconductor laser.

[0013] In one embodiment, the control processing unit includes a signal processing circuit and a microprocessor. The signal processing circuit processes electrical signals from the first detection unit and the second detection unit, and the microprocessor calculates the concentration value of ammonia based on the processed signals.

[0014] In one embodiment, the laser detection instrument for measuring ammonia further includes a display unit, which is electrically connected to the control and processing unit and is used to display the detection results.

[0015] In this invention, the laser emits a wavelength range of 1512.2-1512.3 nm, which matches the absorption spectrum of ammonia gas, enabling precise detection of ammonia concentration with high sensitivity and selectivity. The beam splitter, composed of an optical beam splitter, divides the emitted laser into two paths: one for measurement and the other for reference. The measurement light enters the detection chamber and interacts with the gas to be measured. Part of the laser light is absorbed by the gas, while the remaining portion is received by the first detection unit and converted into an electrical signal. The reference light is directly received by the second detection unit and converted into an electrical signal. The control processing unit processes both electrical signals, comparing the intensity changes of the measurement and reference lights and considering the absorption characteristics of ammonia gas to calculate the concentration of the gas to be measured. By setting a reference optical path, the influence of light source fluctuations and environmental factors on the measurement results is effectively compensated, improving detection accuracy. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of an embodiment of a laser detection instrument for measuring ammonia provided by this utility model.

[0018] Explanation of icon numbers: 100. A laser detection instrument for measuring ammonia; 1. Laser; 2. Spectrometer; 3. Detection chamber; 31. Inlet; 32. Outlet; 4. Detection module; 41. First detection unit; 42. Second detection unit; 5. Control and processing unit; 6. Reflector; 7. Collimating lens; 8. Display unit; 9. Housing.

[0019] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present utility model.

[0021] It should be noted that if the embodiments of this utility model 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.

[0022] Furthermore, if the embodiments of this utility model 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. Therefore, 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 utility model.

[0023] Currently, most ammonia detection instruments on the market are based on the laser detection principle, which to some extent meets the needs of ammonia concentration detection. However, traditional ammonia laser detectors typically use a single measuring light for detection, which can lead to low detection accuracy.

[0024] This invention proposes a laser detection instrument capable of measuring ammonia.

[0025] Please see Figure 1 In one embodiment of this utility model, the laser detection instrument 100 capable of measuring ammonia includes: Laser 1 is used to emit laser light with a wavelength range of 1512.2-1512.3 nm in the direction of the optical path; Beam splitter 2 is located on one side of laser 1 along the optical path direction. The light inlet of beam splitter 2 is connected to the light outlet of laser 1 and is used to split the laser into two different paths: a measurement beam and a reference beam. A detection chamber 3 is located on the side of the beam splitter 2 facing away from the laser 1. The light inlet of the detection chamber 3 is connected to the measurement light outlet of the beam splitter 2. The detection chamber 3 has an inlet 31 and an outlet 32, which are used for the entry and exit of the gas to be measured, respectively. The detection module 4 includes a first detection unit 41 and a second detection unit 42. The light inlet of the first detection unit 41 is connected to the light outlet of the detection chamber 3 to convert the optical signal of the measurement light into an electrical signal. The light inlet of the second detection unit 42 is connected to the reference light outlet of the beam splitter 2 to convert the optical signal of the reference light into an electrical signal. The control processing unit 5 is electrically connected to both the first detection unit 41 and the second detection unit 42, so as to convert the electrical signals detected by the first detection unit 41 and the second detection unit 42 into the concentration value of ammonia.

[0026] In this invention, the laser 1 emits a laser with a wavelength range of 1512.2-1512.3 nm, which matches the absorption spectrum of ammonia gas, enabling precise detection of ammonia concentration with high sensitivity and selectivity. The beam splitter 2, composed of an optical beam splitter, divides the laser emitted by the laser 1 into two paths: one as a measurement beam and the other as a reference beam. The measurement beam enters the detection chamber 3 and interacts with the gas to be measured. Part of the laser light is absorbed by the gas, and part of the measurement beam is received by the first detection unit 41 and converted into an electrical signal. The reference beam is directly received by the second detection unit 42 and converted into an electrical signal. The control processing unit 5 processes the two electrical signals, comparing the intensity changes of the measurement beam and the reference beam, and calculating the concentration of the gas to be measured based on the absorption characteristics of ammonia gas. By setting a reference optical path, the influence of light source fluctuations and environmental factors on the measurement results is effectively compensated, improving detection accuracy.

[0027] Specifically, laser 1 can be a semiconductor laser 1, employing indium gallium arsenide phosphide (InGaAsP) or indium gallium arsenide (InGaAs) quantum well structures to emit laser light in the wavelength range of 1512.2-1512.3 nm. Beam splitter 2 can be composed of optical beam splitters, such as fiber optic beam splitters 2 or polarization beam splitting cubes, as long as a suitable splitting ratio can be selected according to the intensity requirements of the measurement light and reference light. Detection chamber 3 can be a hollow shell with an inlet 31 and an outlet 32 ​​communicating with its interior for the entry and exit of the gas to be measured. Additionally, transparent windows can be provided at the inlet and outlet of detection chamber 3. These transparent windows can reduce laser scattering and reflection on the inner wall of the chamber, ensuring that the laser light can uniformly illuminate the gas to be measured, enhancing the interaction between light and gas, and thus improving detection sensitivity. The first detection unit 41 and the second detection unit 42 are photodetectors, such as silicon photodiodes or indium gallium arsenide photodiodes, used to convert optical signals into electrical signals.

[0028] The specific working principle is as follows: The laser emitted by laser 1 is collimated by collimating lens 7 and then split into two paths by beam splitter 2: a measurement beam and a reference beam. The measurement beam enters the detection chamber 3 and interacts with the ammonia gas to be measured, with some of the laser light being absorbed by the gas. Finally, the measurement beam is received by the first detection unit 41 and converted into an electrical signal. The reference beam is directly received by the second detection unit 42 and converted into an electrical signal. The control processing unit 5 processes the two electrical signals, and by comparing the intensity changes of the measurement beam and the reference beam, combined with the absorption characteristics of ammonia gas, calculates the concentration of the gas to be measured.

[0029] In the embodiments of this utility model, please refer to Figure 1 A laser detection instrument 100 for measuring ammonia gas also includes a reflector 6. The reflector 6 is located at the light outlet of the detection gas chamber 3, and the light outlet of the detection gas chamber 3 is connected to the light inlet of the reflector 6 via a light beam. The light outlet of the reflector 6 is connected to the light inlet of the first detection unit 41 via a light beam. The reflector 6, installed at the light outlet of the detection gas chamber 3, can reflect the measurement light back to the detection gas chamber 3, extending the optical path, enhancing the gas absorption effect, and improving the detection sensitivity. The reflector 6 can efficiently reflect the measurement light back to the gas chamber, reducing light loss, improving light utilization, and enhancing signal strength.

[0030] In the embodiments of this utility model, please refer to Figure 1 The reflector 6 is a concave mirror, typically spherical or parabolic in shape. It can focus parallel light to a point or reflect light rays emitted from the focal point into a parallel beam, which then returns to the detection chamber 3, enhancing the absorption effect. Finally, the measurement light is received by the first detection unit 41 and converted into an electrical signal.

[0031] In the embodiments of this utility model, please refer to Figure 1 A laser detection instrument 100 for measuring ammonia gas also includes a collimating lens 7, which is disposed between the laser 1 and the beam splitter 2 along the optical path. The inlet and outlet of the collimating lens 7 are connected to the outlet of the laser 1 and the inlet of the beam splitter 2, respectively. The collimating lens 7 is used to collimate the laser emitted by the laser 1 into a parallel beam. The collimating lens 7 can be a convex lens or an aspherical lens, which can collimate the diverging beam emitted by the laser 1 into a parallel beam, improve the quality and directionality of the beam, ensure that the beam remains stable during transmission, and reduce light divergence and loss.

[0032] In the embodiments of this utility model, please refer to Figure 1The central axes of laser 1 and beam splitter 2 are both aligned with the central axis of collimating lens 7. This alignment ensures that the measurement and reference beams have highly consistent spot sizes and shapes after beam splitting, guaranteeing precise alignment of the optical path, reducing offset and scattering, and improving the quality and stability of the optical signal.

[0033] In the embodiments of this utility model, please refer to Figure 1 The air inlet 31 and the air outlet 32 ​​are respectively located on the upper and lower sides of the optical path direction. That is, the air inlet 31 and the air outlet 32 ​​are respectively located at the top and bottom of the detection chamber 3, and the light inlet and the light outlet are respectively located on the left and right sides of the detection chamber 3. This allows the gas to flow in the detection chamber 3 in a direction perpendicular to the optical path, avoiding direct interference of the gas flow to the optical path, reducing optical path offset and light spot jitter caused by the gas flow, and improving the stability and reliability of the optical signal.

[0034] In this embodiment of the invention, the laser 1 is a tunable semiconductor laser 1. Using a tunable semiconductor laser 1 allows for adjustment of the emitted laser wavelength as needed, precisely matching the absorption spectrum of ammonia gas, thus improving detection sensitivity and selectivity. The tunable laser 1 can optimize wavelength settings according to different detection environments and gas concentrations, further improving detection accuracy and reliability.

[0035] In the embodiments of this utility model, please refer to Figure 1 A laser detection instrument 100 for measuring ammonia gas also includes a control and processing unit 5. The first detection unit 41 and the second detection unit 42 are both electrically connected to the control and processing unit 5 to convert the electrical signals detected by the first detection unit 41 and the second detection unit 42 into ammonia concentration values. The control and processing unit 5 can automatically process and analyze the acquired electrical signals, converting the electrical signals detected by the first detection unit 41 and the second detection unit 42 into ammonia concentration values, thus realizing intelligent and automated detection. By accurately processing the two electrical signals, the control and processing unit 5 can effectively compensate for the influence of light source fluctuations and environmental changes on the measurement results, improving the accuracy and reliability of the detection.

[0036] In this embodiment of the invention, the control processing unit 5 includes a signal processing circuit and a microprocessor. The signal processing circuit processes the electrical signals from the first detection unit 41 and the second detection unit 42, and the microprocessor calculates the ammonia concentration based on the processed signals. The signal processing circuit amplifies and filters the electrical signals from the first detection unit 41 and the second detection unit 42, effectively removing noise and improving signal quality and stability, thereby providing more accurate data for subsequent concentration calculations. The microprocessor accurately calculates the ammonia concentration based on the processed signals and the absorption characteristics of ammonia, and displays the results through the display unit 8. The microprocessor can also record detection data for subsequent data analysis and trend prediction. The control processing unit 5 may also include a storage unit to amplify, filter, calculate, and store the acquired electrical signals.

[0037] In the embodiments of this utility model, please refer to Figure 1 A laser detector 100 for measuring ammonia also includes a display unit 8, which is electrically connected to a control and processing unit 5 and is used to display the detection results. The display unit 8 can be a liquid crystal display (LCD) or an organic light-emitting diode display (OLED). By connecting to the microprocessor in the control and processing unit 5, it can display ammonia concentration values, instrument status information, historical data, etc.

[0038] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A laser detection instrument for measuring ammonia, characterized in that, include: A laser used to emit laser light with a wavelength range of 1512.2-1512.3 nm in the direction of the optical path; A beam splitter is disposed on one side of the laser along the optical path direction. The light inlet of the beam splitter is connected to the light outlet of the laser, and is used to split the laser into two different paths: a measurement beam and a reference beam. A detection gas chamber is located on the side of the beam splitter away from the laser. The light inlet of the detection gas chamber is connected to the light output port of the beam splitter. The detection gas chamber has an inlet and an outlet, which are used for the gas to be tested to enter and exit, respectively. The detection module includes a first detection unit and a second detection unit. The light inlet of the first detection unit is connected to the light outlet of the detection chamber to convert the optical signal of the measurement light into an electrical signal. The light inlet of the second detection unit is connected to the reference light outlet of the beam splitter to convert the optical signal of the reference light into an electrical signal. The control processing unit is electrically connected to both the first detection unit and the second detection unit to convert the electrical signals detected by the first detection unit and the second detection unit into ammonia concentration values.

2. The laser detection instrument for measuring ammonia as described in claim 1, characterized in that, The laser detection instrument for measuring ammonia also includes a reflector, which is located at the light outlet of the detection chamber. The light outlet of the detection chamber is connected to the light inlet of the reflector via a light beam, and the light outlet of the reflector is connected to the light inlet of the first detection unit via a light beam.

3. The laser detection instrument for measuring ammonia as described in claim 2, characterized in that, The reflector is a concave mirror.

4. The laser detection instrument for measuring ammonia as described in claim 1, characterized in that, The laser detection instrument for measuring ammonia also includes a collimating lens, which is disposed between the laser and the beam splitter along the optical path. The inlet and outlet of the collimating lens are connected to the outlet of the laser and the inlet of the beam splitter, respectively. The collimating lens is used to collimate the laser emitted by the laser into a parallel beam.

5. The laser detection instrument for measuring ammonia as described in claim 4, characterized in that, The central axis of the laser and the central axis of the beam splitter both coincide with the central axis of the collimating lens.

6. The laser detection instrument for measuring ammonia as described in claim 1, characterized in that, The air inlet and the air outlet are positioned opposite each other on the upper and lower sides of the optical path direction.

7. The laser detection instrument for measuring ammonia as described in claim 1, characterized in that, Both the first detection unit and the second detection unit are photodetectors.

8. The laser detection instrument for measuring ammonia as described in claim 1, characterized in that, The laser is a tunable semiconductor laser.

9. A laser detection instrument for measuring ammonia as described in any one of claims 1 to 8, characterized in that, The control processing unit includes a signal processing circuit and a microprocessor. The signal processing circuit processes the electrical signals from the first detection unit and the second detection unit, and the microprocessor calculates the concentration value of ammonia based on the processed signals.

10. A laser detection instrument for measuring ammonia as described in claim 9, characterized in that, The laser detection instrument for measuring ammonia also includes a display unit, which is electrically connected to the control and processing unit and is used to display the detection results.

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