Fluorescence sensor for detecting concentration of object to be detected

Abstract

The utility model discloses a fluorescence sensor for detecting the concentration of an object to be detected, the lower part of a shell is a hollow structure with a certain thickness, the inner side of the upper end of the shell is provided with an accommodating cavity, the accommodating cavity and the hollow structure at the lower part are arranged in an isolating manner, and a sensing film is fixed at the bottom in the accommodating cavity; the first PCB is provided with a through hole for fluorescent light generated by the sensing film to pass through, and the LED is arranged at the upper part of the first PCB; an optical signal collector is arranged on the second PCB; the support is arranged on the inner side of the shell, the first PCB is arranged on the upper portion of the support, the second PCB is arranged on the lower portion of the support, and an optical filter is arranged between the first PCB and the second PCB. And the bottom shell is arranged at the lower part of the bracket. The device is simple in structure and convenient to install, manual welding procedures are reduced, production cost is reduced, and automatic and large-scale production is facilitated.

Description

Technical Field

[0001] This utility model relates to the field of sensor technology, and in particular to a fluorescence sensor for detecting the concentration of an analyte. Background Technology

[0002] Currently, commonly used fluorescent sensors use a plug-in connection to fix a ball-head focusing LED and a photodiode (PD) for light signal acquisition onto a PCB. This fixing method requires precise fixation of the LED angle and PD position within a very limited space, demanding a high level of technical skill from the installers. Furthermore, the LED's illumination range is limited, only illuminating a portion of the sensor's sensing film, which can easily lead to photobleaching of the illuminated area, affecting the film's lifespan. More importantly, fluorescent sensors typically require an excitation filter to filter the LED light into a narrower wavelength and purer color, while an emission filter is needed before the PD to filter LED light and other stray light. Since the filters need to be installed perpendicularly to the LED or PD at a 90-degree angle, machining mounting slots for the excitation filter on the bracket, avoiding interference between the excitation and emission filters, and effectively fixing the two filters become particularly difficult when the LED is installed at an angle. This poses significant challenges to the processing and production of fluorescent sensors, hindering automated mass production and increasing production costs.

[0003] Therefore, those skilled in the art urgently need to develop a fluorescent sensor that is simple in structure, easy to assemble, has few optical components, can be reliably fixed, and can be mass-produced automatically. Utility Model Content

[0004] The purpose of this invention is to address the technical problems existing in the background art by proposing a fluorescence sensor for detecting the concentration of an analyte.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A fluorescence sensor for detecting the concentration of an analyte, comprising at least:

[0007] The outer shell has a hollow structure with a certain thickness at its lower part and a cavity provided on the inner side of the upper end of the outer shell. The cavity is isolated from the lower hollow structure, and the sensing membrane is fixed to the bottom of the cavity.

[0008] The first PCB has a through hole for the fluorescence generated by the sensing film to pass through, and the LED is disposed on the upper part of the first PCB.

[0009] The second PCB is equipped with an optical signal collector.

[0010] A bracket is disposed inside the housing. The first PCB is disposed on the upper part of the bracket, and the second PCB is disposed on the lower part of the bracket. A filter is disposed between the first PCB and the second PCB. The fluorescence generated by the sensing film can reach the optical signal collector through the filter to complete signal acquisition.

[0011] A bottom shell is disposed at the lower part of the bracket, and the outer side of the bottom shell is configured to cooperate with the inner side of the outer shell.

[0012] In one embodiment, the LED's emission angle is between 30 and 160°.

[0013] In one embodiment, the LED is fixedly mounted on the first PCB using a surface mount method.

[0014] In one embodiment, the support is provided with structural members for placing the filter.

[0015] In one embodiment, a focusing lens is also disposed below the filter.

[0016] In one embodiment, the outer side of the bracket is configured to mate with the inner side of the housing.

[0017] In one embodiment, the first PCB and the second PCB are fixedly mounted on the bracket by fasteners.

[0018] In one embodiment, the upper end of the bracket is provided with a first engaging structure that engages with the first PCB, and the lower end of the bracket is provided with a second engaging structure that engages with the second PCB.

[0019] In one embodiment, the sensing membrane is fixedly disposed within the cavity by means of bonding.

[0020] In one embodiment, a threaded structure is provided on the outer side of the upper end of the housing, and the threaded structure is sealed to the wall of the container or pipe containing the medium.

[0021] Compared with the prior art, the above-mentioned technical solution of this utility model has the following beneficial technical effects:

[0022] The above-mentioned structural design of this utility model, since the sensing film is fixedly set in the cavity by bonding, not only facilitates mass automated production, but also effectively reduces the dead volume of the sensor, which is conducive to realizing the rapid response of the sensor.

[0023] Since LEDs can be directly mounted onto the first PCB through automated production processes, with the LED's emitting surface directly facing the sensing film, production eliminates the need for manual adjustment of LED angles and manual soldering, effectively reducing production difficulty and improving product consistency. More importantly, this new structural design effectively avoids spectral broadening caused by LED light scattering, thus eliminating the need for excitation filters, reducing the use of expensive optical filters, lowering product production costs, and simultaneously solving the processing challenge of machining filter fixing grooves at specific angles on the support structure.

[0024] The design of the structural components for placing the filters not only reduces the number of filters required (only a single emission filter is needed), facilitating automated production, but also reduces installation difficulty and improves installation efficiency because the emission filter is sandwiched between two PCBs.

[0025] Since the two PCBs are fixed to the bracket with screws, the filter can be securely fixed between the two PCBs, preventing the filter from becoming loose. At the same time, the first PCB in this sandwich structure also serves to shield the light, effectively preventing the excitation light emitted by the LED from leaking through the edge of the light-emitting filter onto the optical signal collector (PD), thereby minimizing interference caused by excitation light leakage onto the PD.

[0026] The sealing structure between the outer side of the upper end of the housing and the medium container allows the sensor to be used not only for measuring the concentration of the target gas in a gas, but also for measuring the target substance in a liquid, thus expanding the range of applications of the sensor and further improving the economic efficiency of the structure. Attached Figure Description

[0027] Figure 1 This is an exploded structural diagram of an embodiment of the present invention.

[0028] Figure 2 This is a partial cross-sectional structural schematic diagram of an embodiment of the present invention.

[0029] Figure 3 This is a schematic diagram of the connection between the mechanism and the medium container according to an embodiment of the present invention. Detailed Implementation

[0030] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0031] The embodiments of this utility model will be further described below with reference to the accompanying drawings. Those skilled in the art should understand that the embodiments described herein are merely exemplary. The embodiments of this utility model will now be described with reference to the accompanying drawings.

[0032] like Figures 1 to 3 As shown, this utility model provides a fluorescence sensor for detecting the concentration of an analyte. In one embodiment, as... Figure 1 As shown, the optical sensor includes at least a housing 2, a first PCB (Printed Circuit Board) 3, a second PCB 6, a bracket 5, and a bottom shell 7.

[0033] The lower part of the outer shell 2 is a hollow structure with a certain thickness. A cavity 21 is provided on the inner side of the upper end of the outer shell 2. The cavity 21 is isolated from the lower hollow structure; that is, the cavity 21 and the lower hollow structure are not connected. The sensing membrane 1 is disposed at the bottom of the cavity 21. The sensing membrane 1 is fixedly disposed in the cavity 21 by bonding, which not only facilitates mass automated production but also effectively reduces the dead volume of the sensor, thus promoting rapid sensor response.

[0034] The first PCB3 has a through-hole for the fluorescence generated by the sensing film to pass through. The through-hole is preferably smaller than the size of the filter. The LED8 is located on the upper part of the first PCB3. The second PCB6 is equipped with a PD (optical signal collector) 9.

[0035] In order to generate uniform excitation light that evenly illuminates the entire sensing film and thus produces stronger fluorescence, the emission angle of the LED (light-emitting diode) is preferably 30-160°.

[0036] like Figure 2 As shown, the bracket 5 is located inside the outer shell 2, and the outer side of the bracket 5 is matched with the inner side of the outer shell 2.

[0037] The first PCB3 is located on the upper part of the bracket 5, and the second PCB6 is located on the lower part of the bracket 5. A filter 4 is provided between the first PCB3 and the second PCB6. The fluorescence generated by the sensing film 1 can reach the optical signal collector 9 through the filter 4 to complete the signal acquisition.

[0038] Ideally, the sensing film, LED, and vias on the first PCB, along with the optical signal collector, should be located on a central axis from top to bottom to effectively reduce light loss and improve the collection efficiency of the optical signal.

[0039] The first PCB3 and the second PCB6 are fixedly mounted on the bracket by fasteners.

[0040] In other embodiments, the first PCB and the second PCB can also be fixed to the bracket by other means, such as pasting or soldering.

[0041] To further simplify filter installation and enable automated production, a structural component for holding filter 4 is incorporated into bracket 5. This filter arrangement not only reduces the number of filters required, facilitating automated production, but also reduces installation difficulty and improves efficiency by simply clamping the filter between two PCBs.

[0042] Furthermore, since the two PCBs are fixed to the structural components with screws used as fasteners, the filter can be securely fixed between the two PCBs, preventing the filter from loosening. Moreover, because the through-holes are smaller than the filter, this sandwich structure allows the first PCB to act as a light shield, effectively preventing excitation light from leaking through the edges of the filter onto the optical signal collector (PD), thus minimizing interference caused by excitation light leakage onto the PD.

[0043] The bottom shell 7 is located at the lower part of the bracket 5, and the outer side of the bottom shell 7 is matched with the inner side of the outer shell 2.

[0044] In one embodiment, for ease of installation, a first engagement structure for engaging with the first PCB snap-fit ​​3 is provided at the upper end of the bracket 5, and a second engagement structure for engaging with the second PCB snap-fit ​​6 is provided at the lower end of the bracket 5.

[0045] In other embodiments, for ease of installation, the bracket can also be designed to cooperate with the first PCB and the second PCB using other existing structural methods (foolproof design).

[0046] In one embodiment, in order to improve light collection efficiency and effectively collect fluorescence signals onto the PD, a condenser lens is also installed below the filter.

[0047] like Figure 3 As shown, a threaded structure is provided on the outer side of the upper end of the housing 2 to facilitate the formation of a sealed environment between the sensor and the medium container. This structural design allows the sensor to be used not only for measuring the concentration of the analyte in a gas but also for measuring the analyte in a liquid, expanding the sensor's application range and further improving the economic efficiency of the structure.

[0048] In other embodiments, a sealed connection may also be achieved between the sensor and the medium container in other ways.

[0049] The LEDs and PDs in this sensor are connected using a surface-mount method, which simplifies component installation and fixation, and facilitates mass production and automation.

[0050] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited thereto. Various changes can be made within the scope of knowledge possessed by those skilled in the art without departing from the spirit of the present invention.

Claims

1. A fluorescence sensor for detecting the concentration of an analyte, characterized in that, At least including: The outer shell has a hollow structure with a certain thickness at its lower part and a cavity provided on the inner side of the upper end of the outer shell. The cavity is isolated from the lower hollow structure, and the sensing membrane is fixed to the bottom of the cavity. The first PCB has a through hole for the fluorescence generated by the sensing film to pass through, and the LED is disposed on the upper part of the first PCB. The second PCB is equipped with an optical signal collector. A bracket is disposed inside the housing. The first PCB is disposed on the upper part of the bracket, and the second PCB is disposed on the lower part of the bracket. A filter is disposed between the first PCB and the second PCB. The fluorescence generated by the sensing film can reach the optical signal collector through the filter to complete signal acquisition. A bottom shell is disposed at the lower part of the bracket, and the outer side of the bottom shell is configured to cooperate with the inner side of the outer shell.

2. The fluorescent sensor for detecting concentration of an object according to claim 1, wherein, The beam angle of LEDs is between 30 and 160°.

3. The fluorescent sensor for detecting concentration of an object according to claim 2, wherein, The LEDs are fixedly mounted on the first PCB using a surface mount method.

4. The fluorescence sensor for detecting concentration of an object according to claim 1, wherein, The support frame is equipped with structural components for placing the filters.

5. The fluorescence sensor for detecting concentration of an object according to claim 3, wherein, A focusing lens is also provided below the filter.

6. The fluorescence sensor for detecting concentration of an object according to claim 1, wherein, The outer side of the bracket is fitted to the inner side of the outer shell.

7. The fluorescence sensor for detecting concentration of an object according to claim 1, wherein, The first PCB and the second PCB are fixedly mounted on the bracket by fasteners.

8. The fluorescent sensor for detecting concentration of an analyte according to claim 6, wherein, The upper end of the bracket is provided with a first engaging structure that engages with the first PCB, and the lower end of the bracket is provided with a second engaging structure that engages with the second PCB.

9. The fluorescence sensor for detecting concentration of an object according to claim 1, wherein, The sensing membrane is fixedly installed in the cavity by bonding.

10. The fluorescence sensor for detecting concentration of an object according to claim 1, wherein, The outer side of the upper end of the outer shell is provided with a threaded structure, which is sealed to the wall of the container or pipe containing the medium.

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