Dual photoelectric detector with reference gas chamber

Abstract

The utility model provides a dual photoelectric detector with a reference gas chamber, which comprises a shell, a main path detector, a reference detector, a light splitting assembly and a reference gas chamber, wherein the main path detector, the reference detector and the light splitting assembly are arranged in the shell; the reference gas chamber is used for sealing to-be-detected target gas with certain concentration; a window mirror for transmitting detection laser is arranged at the upper part of the shell; the main path detector is arranged corresponding to the window mirror so as to receive the transmitted detection laser and output an electric signal for gas concentration detection; the light splitting assembly is used for splitting reference detection laser from the detection laser and irradiating the reference detection laser to the reference gas chamber; and the reference detector is arranged corresponding to the reference gas chamber so as to receive the reference detection laser absorbed by the reference gas chamber and output an electric signal for laser wavelength calibration. According to the utility model, the main path photoelectric detector, the reference gas chamber and the reference photoelectric detector are coupled in one shell, so that the main path detector, the reference gas chamber and the reference detector are in the same physical environment, the influence of factors such as the external environment is reduced, and the stability of the system is further improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor laser gas detection, in particular to a double photoelectric detector with a reference gas chamber. Background Art

[0002] Tunable Diode Laser Absorption Spectroscopy (TDLAS) leverages the narrow linewidth and wavelength of tunable semiconductor lasers, which change with the injected current, to measure the absorption lines that characterize gas molecules. By analyzing the light absorbed by the gas, it accurately determines the type and concentration of the gas under test, demonstrating high-resolution absorption spectroscopy.

[0003] To achieve precise and accurate measurements, the laser wavelength must cover the absorption wavelength of the gas being measured. Laser wavelength drift can occur due to influences such as circuit noise and the external environment, causing optical power to fluctuate, leading to measurement errors. Currently, wavelength calibration is achieved using a reference gas chamber containing a sealed concentration of the target gas and a reference photodetector. This approach involves using a spectroscopic device (such as a beamsplitter or fiber optic splitter) to split the laser beam. One beam passes through the primary gas chamber and illuminates the primary photodetector for gas concentration detection, while the other beam passes through the reference gas chamber and illuminates the reference photodetector for laser wavelength calibration. Harmonic signals extracted through lock-in amplification technology and processed using a differential algorithm can eliminate measurement errors caused by factors such as optical power variations and the external environment. However, the components used in these systems are often discrete, and the primary and reference gas chambers are bulky. The primary and reference detectors may be located in different physical environments, and the photoelectric characteristics of the photodetectors (such as thermal noise and temperature coefficient) vary with temperature, leading to measurement errors.

[0004] In order to solve the above problems, people have been seeking a better technical solution. Summary of the Invention

[0005] In order to solve the problems existing in the prior art, the main path detector, reference gas chamber and reference detector are placed in the same physical environment, the influence of external environmental factors and other factors is reduced, and the stability of the system is further improved. The utility model proposes a dual photoelectric detector with a reference gas chamber, which couples the main path photoelectric detector, reference gas chamber and reference photoelectric detector inside a shell.

[0006] The technical solution adopted in this utility model is:

[0007] The utility model provides a kind of double photoelectric detector with reference gas chamber, comprising: shell, and main road detector, reference detector, light splitting component and the reference gas chamber of sealing certain concentration target gas to be measured being arranged in the shell inside;

[0008] The upper portion of the shell is provided with a window mirror for transmitting detection laser;

[0009] The main road detector is arranged corresponding to the window mirror to receive the transmitted detection laser, and output electrical signal for gas concentration detection;

[0010] The light splitting component is used for splitting the detection laser transmitted from the window mirror into reference detection laser and irradiating the reference gas chamber;

[0011] The reference detector is arranged corresponding to the reference gas chamber to receive the reference detection laser absorbed by the reference gas chamber, and output electrical signal for laser wavelength calibration.

[0012] Based on the above, the main road detector and the reference detector both include heat sink and photosensitive surface integrated on the heat sink and used for photosensing.

[0013] Based on the above, the heat sink of the main road detector is arranged at the bottom of the shell, and the heat sink of the reference detector is arranged at the side wall of the shell.

[0014] The light splitting component includes a beam splitter arranged in the light path of the detection laser transmitted from the window mirror.

[0015] The detection laser transmitted from the window mirror irradiates the photosensitive surface of the main road detector, the beam splitter splits the detection laser into reference detection laser and irradiates the reference gas chamber, and the reference detection laser transmitted from the reference gas chamber irradiates the photosensitive surface of the reference detector.

[0016] Based on the above, the heat sink of the main road detector and the heat sink of the reference detector are both arranged at the bottom of the shell.

[0017] The light splitting component includes a mirror and a beam splitter arranged in the light path of the detection laser transmitted from the window mirror.

[0018] The detection laser transmitted from the window mirror irradiates the photosensitive surface of the main road detector, the beam splitter splits the detection laser into reference detection laser, and the split reference detection laser irradiates the reference gas chamber after being reflected by the mirror, and the reference detection laser transmitted from the reference gas chamber irradiates the photosensitive surface of the reference detector.

[0019] Based on the above, the heat sink of the main road detector and the heat sink of the reference detector are the same heat sink.

[0020] In a second aspect, the utility model provides a dual photoelectric detector with a reference gas chamber, comprising: a housing, and a main detector, a reference detector, and a reference gas chamber sealed with a certain concentration of a target gas to be measured, arranged inside the housing;

[0021] The upper portion of the housing is provided with a window mirror for transmitting the detection laser;

[0022] The main detector is arranged corresponding to the window mirror to receive the transmitted detection laser and output an electrical signal for gas concentration detection;

[0023] The reference detector is arranged corresponding to the reference air chamber, and the reference air chamber is arranged corresponding to the window mirror;

[0024] The reference detector receives the detection laser after being absorbed by the reference gas chamber, and outputs an electrical signal for laser wavelength calibration.

[0025] Based on the above, the reference air chamber is provided with a light leakage prevention structure.

[0026] Based on the above, the main detector and the reference detector both include a heat sink and a photosensitive surface integrated on the heat sink and used for sensing light; the heat sink of the main detector and the heat sink of the reference detector can be the same heat sink or different heat sinks.

[0027] In a third aspect, the present invention provides a dual photoelectric detector with a reference gas chamber, comprising: a housing, a main detector, and a reference detector;

[0028] The interior of the housing is provided with two sealed chambers, namely a main detection sealed chamber and a reference sealed chamber; the reference sealed chamber is sealed with a certain concentration of the target gas to be measured;

[0029] The main path detector is arranged in the main path detection sealed cavity, and the reference detector is arranged in the reference sealed cavity;

[0030] The upper portion of the housing is provided with a window mirror for transmitting the detection laser;

[0031] The main detector is arranged corresponding to the window mirror to receive the transmitted detection laser and output an electrical signal for gas concentration detection;

[0032] The reference detector is arranged corresponding to the window mirror, receives the detection laser after being absorbed by the gas in the reference sealed cavity, and outputs an electrical signal for laser wavelength calibration.

[0033] Based on the above, the main detector and the reference detector both include a heat sink and a photosensitive surface integrated on the heat sink and used for sensing light; the heat sink of the main detector and the heat sink of the reference detector can be the same heat sink or different heat sinks.

[0034] The present invention has substantial features and advancements over the prior art. Specifically:

[0035] 1. The dual photoelectric detector of the utility model seals the reference gas chamber and the photosensitive surfaces of the main and reference detectors inside the same housing. The environments are the same, so that the photoelectric characteristics of the photosensitive surfaces of the main and reference detectors change in the same way with temperature. When the phase-locked amplification technology is used to extract the harmonic signal for differential algorithm data processing, the measurement errors caused by factors such as changes in laser light power and the external environment can be eliminated.

[0036] 2. The dual photoelectric detector of the present invention has a simple structure, is conducive to large-scale production, and greatly improves the performance stability and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of the structure of the dual photodetector with a reference gas chamber in Example 1.

[0038] Figure 2 Schematic diagram of the structure of the dual photodetector with a reference gas chamber in Example 2.

[0039] Figure 3 Schematic diagram of the structure of the dual photodetector with a reference gas chamber in Example 3.

[0040] Figure 4 Schematic diagram of the structure of the dual photodetector with a reference gas chamber in Example 4.

[0041] Figure 5 Schematic diagram of the structure of the dual photodetector with a reference gas chamber in Example 5.

[0042] Figure 6 Schematic diagram of the structure of the dual photodetector with a reference gas chamber in Example 6.

[0043] In the figure: tube cap 1; tube base 2; first heat sink 3; window mirror 4; first photosensitive surface 5; second photosensitive surface 6; spectrometer 7; reflector 8; reference gas chamber 9; second heat sink 10; tube pin 11; reference gas chamber fixing base 12; partition 13; main detection sealed chamber A; reference sealed chamber B. DETAILED DESCRIPTION

[0044] In order to more clearly understand the above-mentioned objectives, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other without conflict.

[0045] Example 1

[0046] This embodiment provides a dual photodetector with a reference gas chamber, such as Figure 1 As shown, the dotted line in the figure represents the optical path, which includes: a housing composed of a tube cap 1 and a tube base 2, a window mirror 4 for transmitting the detection laser, a main path detector composed of a first heat sink 3 and a first photosensitive surface 5, a reference detector composed of a second photosensitive surface 6 and a second heat sink 10, a spectroscope 7 arranged in the detection laser light path transmitted from the window mirror 4, a reference gas chamber 9, and a tube pin 11; wherein,

[0047] The reference gas chamber 9 is sealed with a target gas to be measured at a certain concentration;

[0048] The window mirror 4 is fixed on the tube cap 1, and the tube cap 1 and the tube pin 11 are fixed on the tube base 2;

[0049] The first heat sink 3 is fixed on the tube base 2. The tube base 2 is designed with a support column extending upward along the side wall of the tube cap 1. The second heat sink 10 is fixed on the support column. The first photosensitive surface 5 and the second photosensitive surface 6 are respectively fixed on the first heat sink 3 and the second heat sink 10.

[0050] The beam splitter 7 is placed between the first photosensitive surface 5 and the window mirror 4, forming a certain angle with the first photosensitive surface 5, and the reflected light is irradiated onto the second photosensitive surface 6 through the reference gas chamber 9. In particular, the reference gas chamber 9 is placed between the beam splitter 7 and the second photosensitive surface 6, close to the second photosensitive surface 6, and away from the first photosensitive surface 5, to prevent light from passing through the reference gas chamber 9 and irradiating the first photosensitive surface 5.

[0051] When the dual photoelectric detector of this embodiment is in use, the detection laser containing the "fingerprint" absorption peak of the target gas to be measured is irradiated into the interior of the dual photoelectric detector through the window mirror 4, and is directly irradiated or transmitted through the spectrometer 7 to the first photosensitive surface 5 and converted into an electrical signal output. The light reflected by the spectrometer is absorbed by the gas in the reference gas chamber 9 and then irradiated to the second photosensitive surface 6 and converted into an electrical signal output.

[0052] Those skilled in the art will appreciate that the electrical signal output by the primary detector, after being processed by a filter and amplifier circuit, can be collected by a microprocessor. Lock-in amplification technology is then used to extract harmonic information of the target gas contained in the light, and combined with interpolation operations, the gas concentration can be calculated. The electrical signal output by the reference detector, after being processed by a filter and amplifier circuit, can be collected by a microprocessor. Lock-in amplification technology is then used to extract harmonic information of the target gas to be measured in the reference gas chamber. By determining whether the position of the harmonic information exceeds a set position range, if so, the laser temperature is controlled using a PID algorithm to achieve laser wavelength calibration.

[0053] The dual photoelectric detector in this embodiment seals the first photosensitive surface 5, the reference gas chamber 9, and the second photosensitive surface 6 inside the same housing and is in the same environment, so that the photoelectric characteristics of the first photosensitive surface 5 and the second photosensitive surface 6 change in the same way with temperature. When the phase-locked amplification technology is used to extract the harmonic signal for differential algorithm data processing, the measurement errors caused by factors such as changes in laser light power and the external environment can be eliminated.

[0054] Example 2

[0055] The difference between this embodiment and embodiment 1 is that:

[0056] like Figure 2 As shown, the spectroscopic component is increased with a reflector 8, the first heat sink 3 and the second heat sink 10 are made into the same heat sink and fixed on the tube base 2, the first photosensitive surface 5 and the second photosensitive surface 6 are respectively fixed on the heat sink, and the reference gas chamber 9 is located between the reflector 8 and the second photosensitive surface 6, away from the first photosensitive surface 5, to prevent light from passing through the reference gas chamber 9 to irradiate the first photosensitive surface 5.

[0057] The light reflected by the beam splitter 7 is reflected by the reflector 8 , absorbed by the reference gas chamber 9 , and then irradiated onto the second photosensitive surface 6 and converted into an electrical signal.

[0058] The dual photodetector in this embodiment has a simple structure and is easy to implement in terms of process by adding a reflector and fixing the first photosensitive surface 3 and the second photosensitive surface 6 on a heat sink, thereby further improving the stability of the system.

[0059] Example 3

[0060] This embodiment provides a dual photodetector with a reference gas chamber, such as Figure 3 As shown, the dotted line in the figure represents the optical path, which includes: a housing composed of a tube cap 1 and a tube base 2, a window mirror 4 for transmitting and detecting laser light, a main detector composed of a first heat sink 3 and a first photosensitive surface 5, a reference detector composed of a second photosensitive surface 6 and the first heat sink 3, a reference gas chamber 9, and a tube pin 11; wherein,

[0061] The reference gas chamber 9 is sealed with a certain concentration of the target gas to be measured;

[0062] The window mirror 4 is fixed on the cap 1 and corresponds to the first light-sensitive surface 5 and the second light-sensitive surface 6, and the cap 1 and the pin 11 are fixed on the tube base 2;

[0063] The first heat sink 3 is fixed on the tube base 2, and the first light-sensitive surface 5 and the second light-sensitive surface 6 are respectively fixed on the first heat sink 3;

[0064] The reference gas chamber 9 is provided with a reference gas chamber fixing seat 12, which is fixed on the first heat sink 3, and the reference gas chamber 9 is fixed in the reference gas chamber fixing seat 12. The reference gas chamber fixing seat 12 cannot leak light, preventing light from the reference gas chamber 9 from shining on the first light-sensitive surface 5.

[0065] In use, the detection laser containing the absorption peak of the "fingerprint" of the target gas to be measured is irradiated into the double photoelectric detector through the window mirror 4, part of the light is irradiated onto the first light-sensitive surface 5 and converted into an electrical signal output; another part of the light is irradiated onto the second light-sensitive surface 6 after being absorbed by the gas in the reference gas chamber 9 and converted into an electrical signal output.

[0066] As can be understood by those skilled in the art, the electrical signal output by the main path detector can be collected by a microprocessor after being processed by a filter and amplifier circuit, and the harmonic information of the target gas contained in the light can be extracted using a phase-locked amplification technology. The gas concentration can be calculated by combining interpolation operation. The electrical signal output by the reference detector can be collected by a microprocessor after being processed by a filter and amplifier circuit, and the harmonic information of the target gas to be measured in the reference gas chamber can be extracted using a phase-locked amplification technology. By judging whether the position of the harmonic information exceeds the set position range, if it exceeds the set range, the laser temperature can be controlled by a PID algorithm, thereby realizing the calibration of the laser wavelength.

[0067] In the double photoelectric detector, the first light-sensitive surface 5, the reference gas chamber 9, and the second light-sensitive surface 6 are sealed in the same housing, and the environment is the same, so that the photoelectric properties of the first light-sensitive surface 5 and the second light-sensitive surface 6 change with temperature in the same way. When the harmonic signal is extracted using a phase-locked amplification technology for differential algorithm data processing, the measurement error caused by factors such as laser optical power change and external environment can be eliminated. Moreover, the first light-sensitive surface 3 and the second light-sensitive surface 6 are fixed on a heat sink, which is simple in structure and easy to implement, and further improves the stability of the system.

[0068] Embodiment 4

[0069] The difference between this embodiment and embodiment 3 is that, as shown in FIG. 4, the first light-sensitive surface 5 and the second light-sensitive surface 6 are fixed on the same heat sink 3, and the reference gas chamber 9 is fixed on the heat sink 3. Figure 4As shown, a second heat sink 10 is added, the first heat sink 3 and the second heat sink 10 are respectively fixed on the tube base 2, and the second photosensitive surface 6 is fixed on the second heat sink 10; the reference air chamber fixing seat 12 is optimized and fixed on the tube base 2.

[0070] Example 5

[0071] The utility model provides a dual photoelectric detector with a reference gas chamber, such as Figure 5 As shown, the dotted line in the figure represents the optical path, which includes: a housing composed of a tube cap 1 and a tube base 2, a window mirror 4 for transmitting and detecting laser light, a main detector composed of a first heat sink 3 and a first photosensitive surface 5, a reference detector composed of a second photosensitive surface 6 and the first heat sink 3, and a tube pin 11; wherein,

[0072] The first heat sink 3 is fixed on the tube base 2, and the first photosensitive surface 5 and the second photosensitive surface 6 are respectively fixed on the first heat sink 3;

[0073] The interior of the housing is divided into two sealed chambers by a partition 13, namely a main detection sealed chamber A and a reference sealed chamber B. The partition 13 is located between the first photosensitive surface 5 and the second photosensitive surface 6 and is fixed to the first heat sink 3. The partition 13 needs to be sealed to prevent gas flow inside the two sealed chambers and to prevent light from being reflected between the two sealed chambers. A certain concentration of the target gas to be measured is sealed in the reference sealed chamber B to form a reference gas chamber.

[0074] The window mirror 4 is fixed on the tube cap 1 and is arranged corresponding to the first photosensitive surface 5 and the second photosensitive surface 6 . The tube cap 1 and the tube pin 11 are fixed on the tube base 2 .

[0075] When the dual photoelectric detector of this embodiment is in use, the detection laser containing the "fingerprint" absorption peak of the target gas to be measured is irradiated into the interior of the dual photoelectric detector through the window mirror 4. Part of the light is irradiated onto the first photosensitive surface 5 and converted into an electrical signal output; the other part of the light is absorbed by the gas in the reference gas chamber and then irradiated onto the second photosensitive surface 6 and converted into an electrical signal output.

[0076] Those skilled in the art will appreciate that the electrical signal output by the primary detector, after being processed by a filter and amplifier circuit, can be collected by a microprocessor. Lock-in amplification technology is then used to extract harmonic information of the target gas contained in the light, and combined with interpolation operations, the gas concentration can be calculated. The electrical signal output by the reference detector, after being processed by a filter and amplifier circuit, can be collected by a microprocessor. Lock-in amplification technology is then used to extract harmonic information of the target gas to be measured in the reference gas chamber. By determining whether the position of the harmonic information exceeds a set position range, if so, the laser temperature is controlled using a PID algorithm to achieve laser wavelength calibration.

[0077] The dual photodetector in this embodiment seals the first photosensitive surface 5, reference gas chamber 9, and second photosensitive surface 6 within the same housing. These surfaces are exposed to the same environment, resulting in their photoelectric properties changing in the same manner with temperature. This eliminates measurement errors caused by factors such as laser power variations and the external environment when using lock-in amplification technology to extract harmonic signals for differential data processing. Furthermore, the first and second photosensitive surfaces 3 and 6 are secured to a single heat sink, resulting in a simple structure and easy manufacturing, further enhancing the system's stability.

[0078] Example 6

[0079] The difference between this embodiment and embodiment 5 is that: Figure 6 As shown, a second heat sink 10 is added, the first heat sink 3 and the second heat sink 10 are respectively fixed on the tube base 2, and the second photosensitive surface 6 is fixed on the second heat sink 10; the partition 13 is optimized, the partition 13 is located between the first photosensitive surface 5 and the second photosensitive surface 6, and is directly fixed on the tube base 2 or is directly composed of the tube base 2.

[0080] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A dual photoelectric detector with a reference gas chamber, characterized in that: The device comprises a housing, a main detector, a reference detector, a spectrometer component and a reference gas chamber sealing a target gas to be measured at a certain concentration, which are arranged inside the housing; The upper portion of the housing is provided with a window mirror for transmitting the detection laser; The main detector is arranged corresponding to the window mirror to receive the transmitted detection laser and output an electrical signal for gas concentration detection; The light splitting component is used to split the detection laser transmitted from the window mirror into a reference detection laser and irradiate the reference gas chamber; The reference detector is arranged corresponding to the reference gas chamber to receive the reference detection laser after being absorbed by the reference gas chamber and output an electrical signal for laser wavelength calibration.

2. The dual photoelectric detector with a reference gas chamber according to claim 1, characterized in that: The main detector and the reference detector both include a heat sink and a photosensitive surface integrated on the heat sink and used for light sensing.

3. The dual photoelectric detector with a reference gas chamber according to claim 2, characterized in that: The heat sink of the main detector is arranged at the bottom of the housing, and the heat sink of the reference detector is arranged on the side wall of the housing; The light splitting component includes a light splitter arranged in the light path of the detection laser transmitted from the window mirror; The detection laser transmitted from the window mirror is irradiated onto the photosensitive surface of the main detector. The spectroscope splits the detection laser into a reference detection laser and irradiates it onto the reference gas chamber. The reference detection laser transmitted from the reference gas chamber is irradiated onto the photosensitive surface of the reference detector.

4. The dual photoelectric detector with a reference gas chamber according to claim 2, characterized in that: The heat sink of the main detector and the heat sink of the reference detector are both arranged at the bottom of the housing; The light splitting component includes a reflector and a light splitter arranged in the light path of the detection laser transmitted from the window mirror; The detection laser transmitted from the window mirror is irradiated onto the photosensitive surface of the main detector, the spectrometer splits the detection laser into a reference detection laser, the split reference detection laser is reflected by the reflector and irradiated onto the reference gas chamber, and the reference detection laser transmitted from the reference gas chamber is irradiated onto the photosensitive surface of the reference detector.

5. The dual photoelectric detector with a reference gas chamber according to claim 4, characterized in that: The heat sink of the main detector and the heat sink of the reference detector are the same heat sink.

6. A dual photoelectric detector with a reference gas chamber, characterized in that: The device comprises a housing, a main detector, a reference detector and a reference gas chamber which seals a target gas to be measured at a certain concentration and is arranged inside the housing; The upper portion of the housing is provided with a window mirror for transmitting the detection laser; The main detector is arranged corresponding to the window mirror to receive the transmitted detection laser and output an electrical signal for gas concentration detection; The reference detector is arranged corresponding to the reference air chamber, and the reference air chamber is arranged corresponding to the window mirror; The reference detector receives the detection laser after being absorbed by the reference gas chamber, and outputs an electrical signal for laser wavelength calibration.

7. The dual photoelectric detector with a reference gas chamber according to claim 6, characterized in that: The reference air chamber is provided with a light leakage prevention structure.

8. The dual photoelectric detector with a reference gas chamber according to claim 6 or 7, characterized in that: The main detector and the reference detector both include a heat sink and a photosensitive surface integrated on the heat sink and used for sensing light; the heat sink of the main detector and the heat sink of the reference detector can be the same heat sink or different heat sinks.

9. A dual photoelectric detector with a reference gas chamber, characterized in that: include: Housing, main detector and reference detector; The interior of the housing is provided with two sealed chambers, namely a main detection sealed chamber and a reference sealed chamber; The reference sealed cavity is sealed with a target gas to be measured at a certain concentration; The main path detector is arranged in the main path detection sealed cavity, and the reference detector is arranged in the reference sealed cavity; The upper portion of the housing is provided with a window mirror for transmitting the detection laser; The main detector is arranged corresponding to the window mirror to receive the transmitted detection laser and output an electrical signal for gas concentration detection; The reference detector is arranged corresponding to the window mirror, receives the detection laser after being absorbed by the gas in the reference sealed cavity, and outputs an electrical signal for laser wavelength calibration.

10. The dual photodetector with a reference gas chamber according to claim 9, characterized in that: The main detector and the reference detector both include a heat sink and a photosensitive surface integrated on the heat sink and used for sensing light; the heat sink of the main detector and the heat sink of the reference detector can be the same heat sink or different heat sinks.

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