CN112763735A

CN112763735A - Light-tight detection device

Info

Publication number: CN112763735A
Application number: CN202110159899.1A
Authority: CN
Inventors: 邹继华; 柳旸; 谢小恒; 徐星存
Original assignee: Ningbo Medical System Biotechnology Co Ltd
Current assignee: Ningbo Medical System Biotechnology Co Ltd
Priority date: 2021-02-05
Filing date: 2021-02-05
Publication date: 2021-05-07

Abstract

The invention discloses a light-tight detection device which comprises a box body, wherein an inner light-tight chamber, an outer light-tight chamber and a driving mechanism for driving a reaction tube to pass through an avoidance through hole to reciprocate between liquid feeding stations in the outer light-tight chamber and the inner light-tight chamber are arranged in the box body, and a detection hole is formed in the side wall of the inner light-tight chamber; be equipped with liquid feeding mechanism and be used for the luminous detection mechanism of light quantum count on the box, be equipped with the secret light subassembly that is used for sheltering from the inspection hole in the interior secret light room, when transport mechanism drives the reaction tube and transports the liquid feeding station that corresponds with liquid feeding mechanism in the interior secret light room, the shelter from the inspection hole is removed to the secret light subassembly for luminous detection mechanism realizes the luminous value detection of reaction tube through the inspection hole. The light-tight detection device disclosed by the invention has the advantages that the sample is conveyed quickly and stably, the conveying process is in a light-tight environment, in addition, the light-tight detection device is completely light-tight in the non-working state of the photon counter, the influence of external light is avoided, and the detection precision is improved.

Description

Light-tight detection device

Technical Field

The invention relates to the technical field of medical instruments, in particular to a light-tight detection device.

Background

The detection of the immune luminescence type is to use the principle of luminescence (including self luminescence, electroluminescence or chemiluminescence) of a substance to be detected, count the detection of the luminescence process, and convert the result into the concentration of the substance to be detected, thereby determining the detection result. The sample to be detected needs to be centrifuged, mixed and incubated for reaction in the early stage of the detection process, and the luminescent substance needs to be detected in the later stage of the detection process. Probing is typically performed in a closed light environment.

On a semi-automatic or full-automatic instrument, the placing in and taking out of a tube to be tested, and the addition of reagents such as an exciting liquid are all carried out in an open environment, so that the problems of insufficient instrument density, high background value and the like are caused, and the consistency and the accuracy of a detection result are influenced. In the existing full-automatic immune luminescence analyzer, an in-situ detection structure is mostly adopted, namely, a certain dense light structure and a detection device are additionally arranged at a certain position on an annular disc or a chain after a sample and a special reagent are subjected to incubation reaction. Due to the limitation of the test tube density and the in-out clearance, the detection sensitivity is reduced due to the defects of reduced density performance, higher detection background value and the like.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: the defect of the prior art is overcome, a light-tight detection device is provided, a sample is conveyed quickly and stably, the conveying process is in a light-tight environment, in addition, the light is completely tight in the non-working state of a photon counter, the influence of external light is avoided, and the detection precision is improved.

The technical scheme adopted by the invention is as follows: the light-tight detection device comprises a box body, wherein an inner light-tight chamber and an outer light-tight chamber are respectively arranged on two sides of an inner cavity of the box body, and an avoidance through hole is formed in one side, close to the outer light-tight chamber, of the inner light-tight chamber;

the box body is provided with a liquid feeding mechanism communicated with the inner dense-light chamber; the box body is also internally provided with a support frame for placing the reaction tube and a driving mechanism for driving the support frame to pass through the avoidance through hole to reciprocate between the outer dense light chamber and the inner dense light chamber;

a light-emitting detection mechanism is further arranged at a position, corresponding to the inner light-tight chamber, on the outer side of the box body, and a detection hole communicated with the light-emitting detection mechanism is formed in the side wall of the inner light-tight chamber; the interior secret light indoor is equipped with the secret light subassembly that is used for sheltering from the inspection hole, works as actuating mechanism drives the reaction tube and transports to interior secret light room and when being located the below of liquid feeding mechanism, the sheltering from to the inspection hole is removed to the secret light subassembly for luminous detection mechanism realizes the luminous value detection of reaction tube through the inspection hole.

Compared with the prior art, the invention has the following advantages:

1) the inner sealed light chamber and the outer sealed light chamber are separated in the operating box body, the whole conveying assembly is arranged in the outer sealed light chamber, the PMT structure corresponds to the inner sealed light chamber, the conveying mechanism arranged in the outer sealed light chamber can rapidly achieve the in and out of a detection sample, meanwhile, excitation liquid is accurately added in a sealed light environment, and the detection efficiency is improved.

2) The compact light assembly corresponding to the detection hole is arranged in the inner compact light chamber, and the PMT detection hole is automatically shielded or separated from the PMT detection hole according to the running position of the transportation mechanism, so that the PMT can be in a power-on state for a long time, and the stability and the detection speed of a detection result are improved; meanwhile, the PMT cannot be failed due to strong ambient light irradiation when not being detected.

3) The novel detection device is simple in detection structure, does not need other complex light-tight control structures, improves detection efficiency, and reduces cost and failure rate.

Furthermore, a dense-light cover plate is arranged on the support frame, and when the driving mechanism drives the support frame to move to a liquid feeding station in the inner dense-light chamber, the circumferential outer edge of the dense-light cover plate is matched with the inner wall of the avoiding through hole. In the structure, the extinction structure is additionally arranged at the communication position of the inner light-tight chamber and the outer light-tight chamber, so that the light can be more effectively blocked, and the light-tight environment of the inner light-tight chamber is ensured.

Still further, the driving assembly comprises a driving motor and a conveying belt, the driving motor is in transmission connection with the conveying belt, and the conveying belt is arranged along the length direction of the box body; the lower end of the support frame is connected with a transmission belt. Simple structure, the conveying is accurate, stable.

As an improvement, a guide sliding rail extending along the length direction of the bottom plate of the inner cavity of the box body is arranged on the bottom plate of the inner cavity of the box body, a sliding block is arranged on the guide sliding rail in a sliding mode, and the lower end of the supporting frame is connected with the sliding block. This improves the setting of structure for the operation of support frame is more stable, can both pass smoothly at every turn and dodge the through-hole, can not take place the interference collision at edge.

And the lower end of the support frame is also provided with a light chopping sheet, and a detection optocoupler is arranged in the outer dense light chamber and used for detecting whether the conveying mechanism conveys the reaction tube to a set position in the inner dense light chamber. In the improved structure, the judgment of the movement stroke of the support frame is realized by detecting the optocoupler and the chopper, the structure is simple, the response is sensitive, and the position judgment is accurate; when the support frame moves to the inner dense light chamber and stops, the reaction tube on the support frame can be accurately positioned at the liquid adding station, the subsequent liquid adding process is more accurate and rapid, and the detection efficiency is improved.

Preferably, the light-tight component comprises a light-tight and smooth block, and a sliding groove in sliding fit with the light-tight and smooth block is formed in the inner side wall of the inner light-tight chamber along the length direction of the inner side wall; and an elastic piece is arranged between the dense and smooth block and the side wall of one end of the inner dense and smooth chamber, which is far away from the avoidance through hole, so that the dense and smooth block always has the tendency of moving towards the avoidance through hole.

And in addition, one end of the sliding chute, which is close to the avoiding through hole, is provided with a limiting boss. The improved mechanism is used for limiting the motion stroke of the dense-smooth block and avoiding the dense-smooth block from being separated from the inner dense-smooth chamber under the action of the elastic force of the elastic piece.

And the support frame is further improved, a baffle parallel to the detection hole is further arranged on the support frame, a light hole is formed in the baffle, and the aperture of the light hole is smaller than that of the detection hole. The arrangement of the improved structure can ensure the consistency of the detection area of the light-emitting part when each time of light quantum detection is carried out, namely, the detection area of each time is the area of the light hole.

And a reflector is arranged on the side wall of one end of the inner dense light chamber, which is far away from the detection hole, and corresponds to the detection hole. The improved structure is additionally provided with the reflector, so that the photon intensity of reaction light in the reaction tube can be effectively increased, and the detection accuracy can be improved under the condition that the photon is weak.

And the matching part of the light-tight cover plate and the avoiding through hole is a circular stepped assembling structure. The improved structure adopts a stepped matching design to more effectively realize light sealing, and adopts a circular outer contour so that the potential light leakage boundary is only an arc line, and compared with other polygons, the improved structure is not easy to leak light at corners and has better light sealing effect; therefore, a sufficient light-tight environment in the inner light-tight chamber is ensured, and the influence of ambient light on a detection result is avoided.

Drawings

Fig. 1 is a schematic structural view of a photodetection device according to the present invention.

Fig. 2 is a schematic structural view of the light-tight detection device of the present invention in a non-detection state with the casing removed.

Fig. 3 is a schematic view showing a detection state of the light-tight detection device of the present invention with the casing removed.

Fig. 4 is a longitudinal sectional view of the non-detection state of the light-tight detection device of the present invention.

Fig. 5 is a longitudinal sectional view showing a detection state of the light-tight detection device of the present invention.

Fig. 6 is a transverse sectional view of the non-detection state of the light-tight detection device of the present invention.

Fig. 7 is a transverse sectional view showing a detection state of the light-tight detection device of the present invention.

Wherein shown in the figure: 100-reaction tube, 01-inner dense light chamber, 02-outer dense light chamber, 03-liquid adding mechanism, 04-luminescence detection mechanism;

the detection device comprises a box body 1, a bypass through hole 2, a detection hole 3, a support frame 4, a light-tight cover plate 5, a step bulge 5.1, a driving motor 6, a conveying belt 7, a guide sliding rail 8, a sliding block 9, a light chopping block 10, a detection optical coupler 11, a light-tight sliding block 12, a sliding chute 13, an elastic part 14, a limiting boss 15, a baffle 16, a light transmission hole 16.1, a reflector 17, an operation hole 18, a driving wheel 19, an inductor 20, a mounting block 21, a mounting hole 22 and a fixing block 23.

Detailed Description

The invention is further described with reference to the following figures and detailed description.

In the description of the present invention, it should be noted that the terms "inside, outside", "bottom plate", "outside wall", "lower end", "below", "upper end", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the term "connected" is to be interpreted broadly, e.g. as a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1 and 2, the invention provides a light-tight detection device, which comprises a rectangular box body 1, wherein an inner light-tight chamber 01 is arranged in the box body 1 and is arranged at one end of the length direction of an inner cavity of the box body 1; the outer dense light chamber 02 is arranged at the other end of the box body 1 in the length direction, and an avoidance through hole 2 is arranged at one side, close to the outer dense light chamber 02, of the inner dense light chamber 01; specifically, in the present embodiment, an installation block 21 is disposed at one end of an inner cavity of the box body 1, an accommodation cavity for accommodating the support frame 4 is disposed in the installation block 21, the accommodation cavity forms an inner light-tight chamber 01, an outer light-tight chamber 02 is formed in a region between the outside of the installation block and the inner side wall of the box body 1 in the box body 1, and the avoidance through hole 2 is disposed on a side wall of the accommodation cavity near one end of the outer light-tight chamber 02;

the box body 1 is also provided with a liquid feeding mechanism 03, particularly the liquid feeding mechanism 03 is arranged at the upper end of the box body 1, a liquid feeding pipe of the liquid feeding mechanism 03 extends into the inner cavity of the inner dense-light chamber 01, and the position, corresponding to the liquid feeding mechanism 03, in the inner dense-light chamber is a liquid feeding station; when the reaction tube 100 moves to the liquid adding station, the liquid adding mechanism can add the corresponding excitation liquid for the luminous reaction into the reaction tube 100;

the box body 1 is also internally provided with a support frame 4 for placing the reaction tube 100 and a driving mechanism for driving the reaction tube 100 to pass through the avoidance through hole 2 and reciprocate between liquid adding stations in the outer dense-light chamber 02 and the inner dense-light chamber 01;

the outer side of the box body 1 is also provided with a light-emitting detection mechanism 04, the light-emitting detection mechanism 04 is arranged at a position corresponding to the inner light-tight chamber 01 on one side wall of the box body 1 in the width direction, a detection hole 3 is arranged on the side wall of the inner light-tight chamber 01, the position of the detection hole 3 corresponds to the detection end of the light-emitting detection mechanism 04, and the light-emitting detection mechanism 04 in the structure is a photon counter (PMT);

the inner dense light chamber 01 is also provided with a dense light assembly for shielding the detection hole 3, and when the driving mechanism drives the reaction tube 100 to be conveyed to a liquid adding station in the inner dense light chamber 01, the dense light assembly releases the shielding of the detection hole 3, so that the luminous value detection of the reaction tube 100 is realized by the luminous detection mechanism 04 through the detection hole 3; the structure fully ensures that the light-emitting detection mechanism 04 is in a sealed light environment in a detection state or a non-use state, and ensures the detection precision.

In this embodiment, preferably, the light-tight assembly includes a light-tight slider 12, and a sliding groove 13 slidably engaged with the light-tight slider 12 is formed on an inner side wall of the inner light-tight chamber 01 along a length direction thereof; and an elastic part 14 is arranged between the dense and smooth block 12 and the side wall of one end of the inner dense and smooth chamber 01, which is far away from the avoidance through hole 3, so that the dense and smooth block 12 always has the tendency of moving towards the avoidance through hole 2, the light shielding of the detection hole 3 is ensured, the light-emitting detection mechanism 04 is in a dense and smooth environment, and the detection precision and accuracy are ensured.

In an improved mode, a limiting boss 15 is arranged at one end, close to the avoiding through hole 3, of the sliding groove 13 and used for limiting the movement stroke of the light sealing sliding block 12 and avoiding the separation of the light sealing sliding block 12 and the inner light sealing chamber 01 under the elastic force action of the elastic piece 14, so that the next detection is influenced. In this embodiment, the elastic member 14 is preferably a cylindrical spring, and the dense-smooth block 12 is provided with a corresponding spring hole 12.1, as shown in fig. 4, one end of the cylindrical spring is fitted in the spring hole 12.1, and the other end of the cylindrical spring abuts against the side wall of the inner dense-smooth chamber 01 far away from the end of the avoiding through hole 2, in order to ensure that the dense-smooth block 12 slides more stably, the number of the cylindrical springs in this embodiment is two, and the two cylindrical springs are vertically distributed.

In this embodiment, as shown in fig. 2, the supporting frame 4 is provided with an insertion hole for placing the reaction tube 100, and the driving mechanism is in transmission connection with the supporting frame 4 and is used for driving the supporting frame 4 to reciprocate along the length direction of the box body 1. In addition, the light-tight cover plate 5 is arranged on the support frame 4 in the structure, when the driving mechanism drives the support frame 4 to move to the liquid adding station in the inner light-tight chamber 01, the outer side wall of the light-tight cover plate 5 is matched with the inner side wall of the avoiding through hole 2, so that the detection environment of absolute light in the inner light-tight chamber 01 is ensured, and the detection precision is improved. Because in this structure, the top of the outer dense light chamber 02 is provided with an operation hole 18 for taking and placing the reaction tube 100, so that a small amount of external light can enter the outer dense light chamber 02, and a corresponding dense light cover plate 5 structure is added in this structure, when the reaction tube 100 enters the inner dense light chamber 01 for detection, the dense light cover plate 5 is in dense light fit in the avoiding through hole 2, so that the influence of a small amount of external light in the outer dense light chamber 02 on the detection structure is avoided, and the detection precision is ensured.

In the structure, as shown in fig. 5, the matching part of the light-tight cover plate 5 and the avoiding through hole 2 is in a stepped assembling structure, so that light is sealed, the light-tight environment in the inner light-tight chamber is ensured, and the influence of ambient light on the detection result is avoided. Specifically, an annular stepped assembling groove 2.1 is arranged on the inner side wall of the avoiding through hole 2, and a step bulge 5.1 corresponding to the assembling groove 2.1 is correspondingly arranged on one side of the light-tight cover plate 5 close to the inner light-tight chamber 01. In addition, the stepped assembling structure in the structure is a circular structure, namely, the step protrusion 5.1 and the assembling groove 2.1 are both circular structures, so that the latent light leakage boundary of the matched edge position is only an arc line after the step protrusion and the assembling groove are arranged, compared with other polygons, the light leakage at the edge is not easy to occur, and the light-tight effect is better.

More specifically, the driving mechanism in this embodiment includes a driving motor 6 and a conveying belt 7, the driving motor 6 is in transmission connection with the conveying belt 7, and the conveying belt 7 is arranged along the length direction of the box body 1; the lower end of the support frame 4 is connected with a transmission belt 7. Preferably, the driving motor 6 is a stepping motor, so that the driving is more stable and the step pitch is accurate.

As shown in fig. 2, 3 and 6, in this embodiment, the driving motor 6 is installed on a lower bottom surface of a section of the box body 1 near the outer sealing chamber 02, an output shaft of the driving motor 6 is connected with a driving wheel 19, the driving wheel is installed on the bottom surface of the outer sealing chamber 02, a driven wheel (not shown in the figure) is installed at the other end of the inner cavity of the box body 1, two ends of the conveying belt 7 are respectively matched with the driving wheel 19 and the driven wheel, so that the conveying belt 7 is driven by the driving motor 6 to operate, and the horizontal movement of the supporting frame 4 is realized. As shown in fig. 2, a guide slide rail 8 extending along the length direction is arranged on the bottom plate of the inner cavity of the box body 1, a slide block 9 is arranged on the guide slide rail 8 in a sliding manner, and the lower end of the support frame 4 is connected with the slide block 9, so that the horizontal movement linearity of the support frame 4 is further ensured, the position deviation cannot occur in the movement process, the support frame 4 can smoothly pass through the avoidance through hole 2 every time, and the reaction tube 100 is transported to a liquid feeding station.

In addition, as shown in fig. 2 and 4, a light chopper 10 is further disposed at the lower end of the support frame 4, and a detection optocoupler 11 is disposed below the 02 position in the outer dense light chamber and the 01 position in the inner dense light chamber and is used for detecting whether the transport mechanism accurately transports the reaction tube 100 to a position corresponding to the liquid adding station in the inner dense light chamber 01.

The support frame 4 is also provided with a baffle 16 parallel to the detection hole 3, the baffle 16 is provided with a light hole 16.1, and the aperture of the light hole 16.1 is smaller than that of the detection hole 3.

In this embodiment, as shown in fig. 6, a reflective mirror 17 is disposed on the sidewall of the end of the inner dense light chamber 01 away from the detection hole 03 and corresponding to the detection hole 3, so as to increase the photon intensity after the luminescence reaction of the reaction tube 100 and improve the detection accuracy. Specifically, in this embodiment, the side wall of the accommodating cavity opposite to the detection hole 3 is provided with a mounting hole 22, a corresponding fixing block 23 is inserted into the mounting hole 22, and the end face of the fixing block 23 close to the accommodating cavity is provided with the reflective mirror 17, so that the reflective mirror 17 is convenient to assemble and disassemble.

In the structure, in order to ensure the automation of the detection process, a general controller is further arranged in the detection device, a corresponding inductor 20 is arranged on the support frame 4, the inductor 20 is in signal connection with the controller, and the driving motor 6, the detection optocoupler 11, the photon counter and the liquid adding mechanism 03 are all in signal connection with the controller, so that the automation degree is improved.

The working principle is as follows:

firstly, placing a reaction tube 100 filled with a sample into an insertion hole on a support frame 4, sensing the reaction tube 100 by a sensor 20 at the moment, transmitting a signal to a controller, controlling a driving motor 6 to operate by the controller, driving the support frame 4 to operate towards an inner dense light chamber 01, pushing a dense smooth block 12 to slide towards a direction far away from an avoidance through hole 2 by the end part of the support frame 4 when the support frame 4 enters the inner dense light chamber 01 until a detection optical coupler 11 detects a light chopping sheet 10, stopping the driving motor 6, just moving the support frame 4 to a liquid adding station at the moment, controlling a liquid adding mechanism to carry out liquid adding operation on the reaction tube 100 by the controller, completely exposing a detection hole 3 at the liquid adding station, starting a PMT after waiting for a set time, and detecting the number of photons generated after the luminous reaction of the reaction tube 100 through the detection hole 3; after the detection is finished, the controller controls the driving motor 6 to reset to drive the support frame 4 to reset to the outer light-tight chamber 02, and in the process that the support frame 4 is far away from the inner light-tight chamber 01, because the thrust action of the support frame 4 is lost by the light-tight sliding block 12, the light-tight sliding block 12 resets and slides towards the position of the avoidance through hole 2 under the elastic action of the elastic piece 14 until the outer end face of the light-tight sliding block 12 abuts against the limiting boss 15, at the moment, the light-tight sliding block 12 completely blocks the detection hole 3 again, and the PMT is ensured not to contact with external light and is in a light-tight environment; after the support frame 4 is reset, the reaction tube 100 is taken out, and then the next newly desired reaction tube is placed in for the next period of detection, so that the rapid detection of the sample is realized through the circulation.

The foregoing has described preferred embodiments of the present invention and is not to be construed as limiting the claims. The present invention is not limited to the above embodiments, and the specific structure thereof is allowed to vary, and various changes made within the scope of the independent claims of the present invention are within the scope of the present invention.

Claims

1. A secret light detection device is characterized in that: the light-tight box comprises a box body (1), wherein an inner light-tight chamber (01) and an outer light-tight chamber (02) are respectively arranged on two sides of an inner cavity of the box body (1), and an avoidance through hole (2) is formed in one side, close to the outer light-tight chamber (02), of the inner light-tight chamber (01);

a liquid adding mechanism (03) communicated with the inner dense-light chamber (01) is arranged on the box body (1); the box body (1) is also internally provided with a support frame (4) for placing the reaction tube (100) and a driving mechanism for driving the support frame (4) to pass through the avoidance through hole (2) and to reciprocate between the outer dense light chamber (02) and the inner dense light chamber (01);

a light-emitting detection mechanism (04) is further arranged at a position, corresponding to the inner light-tight chamber (01), on the outer side of the box body (1), and a detection hole (3) communicated with the light-emitting detection mechanism (04) is formed in the side wall of the inner light-tight chamber (01); be equipped with in interior secret light room (01) and be used for sheltering from the secret light subassembly of inspection hole (3), work as actuating mechanism drives reaction tube (100) and transports to interior secret light room (01) and be located the below of liquid feeding mechanism (03), secret light subassembly removes the sheltering from inspection hole (3) for luminous detection mechanism (04) realize the luminous value of reaction tube (100) through inspection hole (3) and detect.

2. The photodetection device according to claim 1, characterized in that: be equipped with on support frame (4) and seal light apron (5), when actuating mechanism drives support frame (4) and moves to interior secret light room (01) and be located the below of liquid feeding mechanism (03), the circumference outward flange of secret light apron (5) with dodge through-hole (2) inner wall and cooperate.

3. The photodetection device according to claim 2, characterized in that: the driving mechanism comprises a driving motor (6) and a conveying belt (7), the driving motor (6) is in transmission connection with the conveying belt (7), and the conveying belt (7) is arranged along the length direction of the box body (1); the lower end of the support frame (4) is connected with a transmission belt (7).

4. The photodetection device according to claim 2, characterized in that: the guide sliding rail (8) extending along the length direction of the bottom plate of the inner cavity of the box body (1), a sliding block (9) is arranged on the guide sliding rail (8) in a sliding mode, and the lower end of the support frame (4) is connected with the sliding block (9).

5. The photodetection device according to claim 4, characterized in that: the lower end of the support frame (4) is also provided with a light chopping sheet (10), and a detection optocoupler (11) is arranged in the outer dense light chamber (02) and used for detecting whether the reaction tube (100) is transported to a set position in the inner dense light chamber (01) by a transport mechanism.

6. The photodetection device according to claim 1, characterized in that: the light-tight component comprises a light-tight sliding block (12), and a sliding groove (13) which is in sliding fit with the light-tight sliding block (12) is formed in the inner side wall of the inner light-tight chamber (01) along the length direction of the inner side wall; and an elastic piece (14) is arranged between the dense and smooth block (12) and the side wall of one end of the inner dense and smooth chamber (01) far away from the avoiding through hole (3), so that the dense and smooth sliding block (12) always has the tendency of moving towards the avoiding through hole (2).

7. The photodetection device according to claim 6, characterized in that: and a limiting boss (15) is arranged at one end of the sliding groove (13) close to the avoiding through hole (3).

8. The photodetection device according to claim 3, characterized in that: the support frame (4) is further provided with a baffle (16) parallel to the detection hole (3), the baffle (16) is provided with a light hole (16.1), and the aperture of the light hole (16.1) is smaller than that of the detection hole (3).

9. The photodetection device according to claim 1, characterized in that: and a reflector (17) is arranged on the side wall of one end of the inner dense light chamber (01) far away from the detection hole (03) and corresponds to the detection hole (3).

10. The photodetection device according to any one of claims 1 to 9, characterized in that: the matching part of the light-tight cover plate (5) and the avoiding through hole (2) is a circular stepped assembling structure.