LED integrated photoacoustic cavity structure

Abstract

The utility model discloses a light-emitting diode (LED) integrated photoacoustic cavity structure, which comprises an acousto-optic cavity shell, an acousto-optic cavity body is arranged in the acousto-optic cavity shell, gas is filled in the acousto-optic cavity body, and a quartz tuning fork base is arranged at the top of the acousto-optic cavity shell; the quartz tuning fork is clamped in the quartz tuning fork base, and the quartz tuning fork is inversely arranged in the cavity body of the acousto-optic cavity downwards along the longitudinal direction, so that the structure is compact, and the occupied space is reduced; a lens is installed in the side wall of the acousto-optic cavity shell, an LED lamp is installed in the acousto-optic cavity shell, the LED lamp directly faces the lens, the LED lamp is small in size, and the occupied space is reduced. Light emitted by the LED lamp is focused by the lens and then irradiated to gas in the cavity of the acousto-optic cavity to generate a photoacoustic signal, and the quartz tuning fork absorbs the photoacoustic signal.

Description

Technical Field

[0001] The utility model belongs to the technical field of photoacoustic cavities, and particularly relates to a photoacoustic cavity structure integrated with an LED. Background Art

[0002] A sample sealed in a photoacoustic cell is irradiated with a monochromatic light beam with adjustable intensity. The sample absorbs the light energy and de-excites by releasing heat energy. The released heat energy causes the sample and the surrounding medium to be periodically heated according to the modulation frequency of the light, thereby causing the medium to generate periodic pressure fluctuations. Such pressure fluctuations can be detected by a sensitive microphone or a piezoelectric ceramic microphone and amplified to obtain a photoacoustic signal, which is the photoacoustic effect.

[0003] Photoacoustic detection technology is a spectral sensing technology based on the photoacoustic effect, which can realize the detection and analysis of sample components and concentrations. The photoacoustic cavity is the most critical component affecting the detection performance, and the geometric structure of the photoacoustic cavity has an important influence on the sensitivity. According to the working mode of the photoacoustic cavity, it can be divided into a resonant type and a non-resonant type. The resonant photoacoustic cavity utilizes the resonance enhancement characteristic of sound waves to achieve higher detection sensitivity.

[0004] In the entire photoacoustic cavity structure, a quartz tuning fork (acoustic sensor) is also required, and a preamplifier circuit is arranged outside the photoacoustic cavity structure. The preamplifier circuit is used to amplify the current signal converted by the quartz tuning fork, which results in a large size and volume of the photoacoustic cavity structure. Content of the Utility Model

[0005] The purpose of the utility model is to provide a photoacoustic cavity structure integrated with an LED. By inverting the quartz tuning fork and using an LED lamp as the light source, the volume of the photoacoustic cavity structure can be reduced.

[0006] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0007] A photoacoustic cavity structure integrated with an LED includes a photoacoustic cavity housing. An acoustic-optical cavity is provided inside the photoacoustic cavity housing, and a gas is filled in the acoustic-optical cavity. A quartz tuning fork base is installed on the top of the photoacoustic cavity housing;

[0008] The quartz tuning fork is clamped in the quartz tuning fork base, and the quartz tuning fork is inverted longitudinally downward in the acoustic-optical cavity to make the structure compact and reduce the occupied space; a lens is installed inside the side wall of the photoacoustic cavity housing, and an LED lamp is installed inside the photoacoustic cavity housing. The LED lamp is directly opposite to the lens. The LED lamp has a small volume and reduces the occupied space; the light emitted by the LED lamp is focused by the lens and then irradiates into the gas inside the acoustic-optical cavity to generate a photoacoustic signal, and the quartz tuning fork absorbs the photoacoustic signal.

[0009] Preferably, a receiving groove is formed at the bottom of the acousto-optic cavity housing, and the preamplifier circuit is installed in the receiving groove to reduce the space occupied by the photoacoustic cavity structure.

[0010] Preferably, a top cover is installed at the top of the acousto-optic cavity housing, and the top cover is used to fix the quartz tuning fork base and seal the upper port of the acousto-optic cavity.

[0011] Preferably, a base is installed at the bottom of the acousto-optic cavity housing, and the base is used to seal the lower port of the acousto-optic cavity.

[0012] Preferably, screws are used to detachably install the quartz tuning fork base, the top cover and the base respectively.

[0013] Preferably, a wire passing hole is formed in the side wall of the acousto-optic cavity housing, and a power line passes through the wire passing hole and is arranged inside the acousto-optic cavity housing to supply power to the LED lamp.

[0014] Preferably, an air flow hole is formed in the side wall of the acousto-optic cavity housing, and air flow is circulated inside and outside through the air flow hole.

[0015] The beneficial effects of the present utility model are as follows:

[0016] The quartz tuning fork is clamped in the quartz tuning fork base, and the quartz tuning fork is longitudinally inverted and placed in the acousto-optic cavity. By longitudinally accommodating the quartz tuning fork in the acousto-optic cavity housing, the space occupied by the structures of the quartz tuning fork and the acousto-optic cavity housing in the longitudinal direction is reduced, so that the structure of the photoacoustic cavity is compact and the occupied space is reduced. The LED lamp is used to replace the laser, and the LED lamp has a small volume, reducing the occupied space. The preamplifier circuit is arranged inside the acousto-optic cavity housing, which can reduce the volume of the photoacoustic cavity structure after assembly and reduce the overall occupied space. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is an exploded view of the photoacoustic cavity structure observed from one side;

[0018] Figure 2 is an exploded view of the photoacoustic cavity structure observed from the other side;

[0019] Figure 3 is an exploded view of the photoacoustic cavity structure observed from the side.

[0020] Reference Signs:

[0021] 1. First screw; 2. Top cover; 3. LED lamp; 4. Quartz tuning fork; 5. Quartz tuning fork base; 6. Second screw; 7. Lens; 8. Base; 9. Third screw; 10. Photoacoustic cavity housing, 11. Wire passing hole; 12. Air flow hole. Detailed implementation manner

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0023] In the entire photoacoustic cavity structure, a quartz tuning fork (acoustic sensor) is also required, and a preamplifier circuit is provided outside the photoacoustic cavity structure. The preamplifier circuit is used to amplify the current signal converted by the quartz tuning fork, which results in a large size and volume of the photoacoustic cavity structure and is convenient to use.

[0024] For the above technical problems, referring to Figure 1 , Figure 2 and Figure 3 , this embodiment provides a photoacoustic cavity structure integrated with an LED, including a photoacoustic cavity housing 10. An acoustic-optical cavity is provided inside the photoacoustic cavity housing 10, and a gas is filled in the acoustic-optical cavity. The gas can be methane, carbon dioxide, carbon monoxide, etc.

[0025] The quartz tuning fork base 5 is installed on the top of the photoacoustic cavity housing 10.

[0026] The quartz tuning fork 4 is clamped in the quartz tuning fork base 5. The quartz tuning fork 4 is inverted longitudinally downward in the acoustic-optical cavity. By accommodating the quartz tuning fork 4 longitudinally in the photoacoustic cavity housing 10, the space occupied by the structure of the quartz tuning fork 4 and the photoacoustic cavity housing 10 in the longitudinal direction is reduced, so that the structure of the photoacoustic cavity is compact and the occupied space is reduced.

[0027] A lens 7 is installed inside the side wall of the photoacoustic cavity housing 10, and an LED lamp 3 is installed inside the photoacoustic cavity housing 10. The LED lamp 3 faces the lens 7. The light source of the existing photoacoustic cavity structure uses a fiber laser or a laser, which occupies a large volume.

[0028] The internal material of the photoacoustic cavity is TC4 titanium alloy, which is more corrosion-resistant and can make the photoacoustic cavity have a longer service life.

[0029] In this embodiment, the LED lamp is used to replace the laser. The LED lamp 3 has a small volume and reduces the occupied space.

[0030] The light emitted by the LED lamp 3 is focused by the lens 7 and then irradiates the gas inside the acousto-optic cavity to generate an optoacoustic signal, and the quartz tuning fork absorbs the optoacoustic signal to achieve optoacoustic detection.

[0031] A receiving groove is provided at the bottom of the acousto-optic cavity housing 10, and the preamplifier circuit is installed in the receiving groove. In the prior art, the preamplifier circuit or the amplifier is arranged outside the acousto-optic cavity housing 10. In this embodiment, the preamplifier circuit is arranged inside the acousto-optic cavity housing 10, which can reduce

[0032] the volume of the assembled optoacoustic cavity structure and reduce the overall occupied space.

[0033] A top cover 2 is installed at the top of the acousto-optic cavity housing 10. The top cover 2 is used to fix the quartz tuning fork base 5, and the top cover 2 is closely attached to the upper port of the acousto-optic cavity to seal the upper port of the acousto-optic cavity and improve the airtightness.

[0034] A base 8 is installed at the bottom of the acousto-optic cavity housing 10. The base 8 is closely attached to the lower port of the acousto-optic cavity. The base 8 is used to seal the lower port of the acousto-optic cavity and improve the airtightness.

[0035] The detachable installation of the quartz tuning fork base 5, the top cover 2 and the base 8 is realized by screws respectively. Specifically, the second screw 6 is used to detachably install the quartz tuning fork base 5 on the acousto-optic cavity housing 10, the first screw 1 is used to detachably install the top cover 2 on the acousto-optic cavity housing 10, and the third screw 9 is used to detachably install the base 8 at the bottom of the acousto-optic cavity housing 10.

[0036] A wire passing hole 11 is provided in the side wall of the acousto-optic cavity housing 10, and the power line passes through the wire passing hole 11 and is arranged inside the acousto-optic cavity housing 10 to supply power to the LED lamp 3.

[0037] An air flow hole 12 is provided in the side wall of the acousto-optic cavity housing 10, and the air flow realizes internal and external circulation through the air flow hole 12.

[0038] Working principle:

[0039] The quartz tuning fork 4 is clamped within the quartz tuning fork base 5. The quartz tuning fork 4 is placed longitudinally downward within the acousto-optic cavity. By longitudinally accommodating the quartz tuning fork 4 within the acousto-optic cavity housing 10, the space occupied by the structures of the quartz tuning fork 4 and the acousto-optic cavity housing 10 in the longitudinal direction is reduced, making the structure of the photoacoustic cavity compact and reducing the occupied space. The laser is replaced with the LED lamp. The LED lamp 3 is small in size, reducing the occupied space. The pre-amplification circuit is arranged inside the acousto-optic cavity housing 10, which can reduce the volume of the assembled photoacoustic cavity structure and the overall occupied space.

[0040] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An LED integrated photoacoustic cavity structure, comprising a photoacoustic cavity shell (10), wherein a photoacoustic cavity body is provided inside the photoacoustic cavity shell (10), and the photoacoustic cavity body is filled with gas, characterized in that , a quartz tuning fork base (5) is mounted on the top of the acousto-optic cavity housing (10); The quartz tuning fork (4) is clamped in the quartz tuning fork base (5), and the quartz tuning fork (4) is placed upside down in the acoustic-optical cavity along the longitudinal direction, so as to make the structure compact and reduce the occupied space; A lens (7) is installed in the side wall of the acoustic-optical cavity housing (10); the LED lamp (3) is installed inside the acoustic-optical cavity housing (10); the LED lamp (3) is directly opposite the lens (7); the LED lamp (3) is small in size, and occupies less space; The light emitted by the LED lamp (3) is focused by the lens (7) and irradiated into the gas inside the acousto-optic cavity to generate a photoacoustic signal, and the quartz tuning fork absorbs the photoacoustic signal.

2. According to the LED integrated photoacoustic cavity structure of claim 1, it is characterized in that A receiving groove is provided at the bottom of the acousto-optic cavity housing (10), and the preamplifier circuit is installed in the receiving groove to reduce the space occupied by the acousto-optic cavity structure.

3. According to the LED integrated photoacoustic cavity structure of claim 1, it is characterized in that A top cover (2) is installed on the top of the acousto-optic cavity housing (10), and the top cover (2) is used to fix the quartz tuning fork base (5) and to seal the upper port of the acousto-optic cavity body.

4. According to claim 3, the LED integrated photoacoustic cavity structure is characterized in that A base (8) is installed at the bottom of the acousto-optic cavity housing (10), and the base (8) is used to seal the lower port of the acousto-optic cavity.

5. According to claim 4, the LED integrated photoacoustic cavity structure is characterized in that , screws are used to respectively realize the detachable installation of the quartz tuning fork base (5), the top cover (2) and the base (8).

6. According to claim 1, the LED integrated photoacoustic cavity structure is characterized in that A wire-passing hole (11) is provided in the side wall of the acousto-optic cavity housing (10); a power line is passed through the wire-passing hole (11) and arranged inside the acousto-optic cavity housing (10) to supply power to the LED lamp (3).

7. According to claim 1, the LED integrated photoacoustic cavity structure is characterized in that An air flow hole (12) is provided in the side wall of the acousto-optic cavity housing (10), and air flows inside and outside through the air flow hole (12).

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