Portable nondestructive testing Fourier transform infrared spectrometer

Abstract

The invention provides a portable nondestructive testing Fourier transform infrared spectrometer, and relates to the technical field of spectral imaging. A sampling window is arranged on one side surface of the infrared spectrometer box body; an infrared light beam generated by the light source is divided into transmission light and reflection light through the beam splitter, the transmission light and the reflection light form an optical path difference, then the infrared light beam with the optical path difference enters a sample from the sampling window through the crystal, and the infrared light beam returned from the sample is acquired by the infrared signal detector. The position of a sampling outlet is arranged on the side surface of the instrument, and a forward probe is designed, so that nondestructive testing is realized, and sampling damage caused by infrared spectrum testing of a service material is avoided. In addition, the swing type parallel reflecting mirror group is adopted, so that a moving mirror motion control mechanism is simplified, and miniaturization and portability of the case are realized.

Description

Technical Field

[0001] The invention belongs to the technical field of spectral imaging, and in particular relates to a portable Fourier transform infrared spectrometer. Background Art

[0002] As an important tool in modern analytical chemistry, the core principle of Fourier transform infrared spectrometer is based on the infrared absorption spectrum produced by the transition of molecular vibration energy levels. The instrument can provide rich information on molecular structure and chemical composition by scanning the absorption of samples in the infrared light region. Since its advent, Fourier transform infrared spectrometer has been widely used in many fields such as materials, chemistry, chemical engineering, environment, textile, biomedicine, and pharmacy due to its advantages such as fast scanning rate, high resolution, stable results, and low sample requirements.

[0003] With the continuous development of technology, Fourier transform infrared spectrometers have gradually developed a variety of test modes, such as transmission, attenuated total reflection, infrared polarization, gas pool, liquid pool, etc., to meet the testing needs of different sample types. However, although these test modes perform well in laboratory environments, in practical applications, especially at engineering sites, existing Fourier transform infrared spectrometers still face many challenges. Among them, the most prominent problem is that sampling and testing methods need to be adopted. The sample is placed on the surface of the infrared spectrometer, and the infrared light is focused on the surface of the ATR (attenuated total reflectance) accessory. The infrared light enters the sample surface and returns. The ATR accessory measures the infrared characteristic spectrum of the sample surface. At the same time, if the sample is not tightly fitted with the ATR accessory, the infrared characteristic spectrum of the sample cannot be measured. Therefore, a press is required on the sample to fit the sample to the ATR accessory through the press. However, it is impossible to sample the service material at the engineering site, and it is even more difficult to place a press for non-destructive testing of the service material. In addition, due to the complex optical path design, the traditional Fourier transform infrared spectrometer is bulky and inconvenient to carry, and cannot meet the needs of fast and convenient infrared spectrum detection at the engineering site. Summary of the invention

[0004] Therefore, the technical problem to be solved by the present invention is to provide a portable non-destructive testing Fourier transform infrared spectrometer, which can realize non-destructive testing of service materials.

[0005] The portable non-destructive testing Fourier transform infrared spectrometer disclosed in the present invention is in the shape of a box, and a sampling window is arranged on one side of the box; the infrared light beam generated by a light source is divided into transmitted light and reflected light by a beam splitter, an optical path difference is formed between the transmitted light and the reflected light, and then the infrared light beam with the optical path difference passes through a crystal and enters a sample from the sampling window, and the infrared light beam returned from the sample is acquired by an infrared signal detector.

[0006] Furthermore, the crystal is prism-shaped, and one end of the prism-shaped crystal protrudes out of the sampling window.

[0007] Furthermore, the protrusion distance of the crystal is 0 to 1 mm.

[0008] Furthermore, the crystal is a diamond crystal.

[0009] Furthermore, the infrared light beam generated by the light source enters the beam splitter via the first parabolic reflector; the reflected light returns to the beam splitter via the first plane reflector; the transmitted light returns to the beam splitter via the parallel reflector group and the fourth plane reflector; the parallel reflector group swings to make the infrared light beam generate an optical path difference that changes with the swing angle; the beam splitter merges the two returning infrared light beams, and the beam splitter merges the two returning infrared light beams, and the beams enter the reflector group after being reflected by the fifth plane reflector;

[0010] The reflector group is arranged at the sampling window position; the reflector group consists of a first reflector group and a second reflector group, the first reflector group consists of a sixth plane reflector and a second parabolic reflector, and the second reflector group consists of a seventh plane reflector and a third parabolic reflector; the infrared light beam reflected by the fifth plane reflector passes through the sixth plane reflector and the second parabolic reflector successively, and then enters the sample through the sampling window, and the infrared light beam returned from the sample passes through the third parabolic reflector and the seventh plane reflector respectively and then is acquired by the infrared signal detector.

[0011] The infrared spectrometer according to claim 5 is characterized in that the parallel reflector group includes a swing shaft, a second plane reflector and a third plane reflector; the second plane reflector and the third plane reflector are connected by a connecting rod and kept parallel, and the swing shaft is set at the center of the outer side of the second plane reflector.

[0012] Furthermore, the swing shaft swings at a constant speed, and the swing angle is 90°.

[0013] Furthermore, the included angle between the second plane reflector and the connecting rod is 45°.

[0014] Furthermore, the infrared signal detector is connected to a data acquisition card, and the data collected by the data acquisition card is converted and then transmitted to the outside by a radio signal transmitter.

[0015] Furthermore, a handle is provided on the other side of the infrared spectrometer housing opposite to the sampling window.

[0016] Beneficial effects:

[0017] The reflector group of the present invention adjusts the sampling outlet position to the front side of the instrument and adopts a forward probe design to realize non-destructive testing and avoid sampling damage caused by infrared spectrum testing of service materials.

[0018] Since the sampling outlet is set on the front side of the instrument, when in use, one side of the instrument sampling outlet is pressed onto the horizontally placed engineering service material. The machine's own weight can achieve a close fit between the sample and the detection window, thereby ensuring the stability of the infrared spectrum acquisition data and reducing data noise.

[0019] By using prismatic diamond crystals, there is no need to set up a press. Under the pressure of its own weight, the sample and the crystal can still achieve close contact, reducing the spectral signal noise.

[0020] In addition, the use of a swinging parallel mirror group simplifies the moving mirror motion control mechanism, realizes the miniaturization and portability of the chassis, and is convenient for use on engineering sites. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0022] Figure 1 This is a schematic diagram of the structure of the infrared spectrometer according to Example 1 of the present invention.

[0023] In the figure, 1: light source, 2: first parabolic reflector, 3: beam splitter, 4: first plane reflector, 5: parallel reflector group, 501: swing axis, 502: second plane reflector, 503: third plane reflector, 6: fourth plane reflector, 7: fifth plane reflector, 8: first reflector group, 801: sixth plane reflector, 802: second parabolic reflector, 9: second reflector group, 901: seventh plane reflector, 902: third parabolic reflector, 10: crystal, 11: sample, 12: infrared signal detector, 13: data acquisition card, 14: radio signal transmitter, 15: infrared spectrometer box, 16: handle. DETAILED DESCRIPTION

[0024] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. The principles and features of the present invention are described below in combination with the accompanying drawings. It should be noted that the embodiments in this application and the features in the embodiments can be combined with each other without conflict. The embodiments are only used to explain the present invention and are not used to limit the scope of the present invention.

[0025] Example 1

[0026] In order to solve the technical problem pointed out in the background technology that it is impossible to sample the service materials at the engineering site and it is impossible to implement non-destructive testing of the service materials, the design ideas of the present invention are as follows:

[0027] like Figure 1 As shown, unlike the prior art in which the sampling window is arranged on the upper surface of the infrared spectrometer, the sampling window is arranged on a side surface (front side surface) of the infrared spectrometer housing 15 in this embodiment.

[0028] The infrared light beam generated by the light source 1 is divided into transmitted light and reflected light by the beam splitter 3, and the transmitted light and the reflected light form an optical path difference. Then the infrared light beam with the optical path difference passes through the crystal 10 and enters the sample 11 from the sampling window. The infrared light beam returned from the sample 11 is acquired by the infrared signal detector 12.

[0029] Adjust the infrared beam outlet to the front side of the instrument, and directly contact the sample to be tested through the front side sampling window to achieve non-destructive testing of the infrared spectrum of structures and materials. Adjusting to the front side can detect scenes such as the ground where there is no way to take samples or where sampling will cause structural damage. This solves the problem that the existing technology cuts a piece of sample, then places it on the upper surface of the instrument, and presses it with a press for testing, which is not suitable for the above-mentioned scenes that cannot be damaged.

[0030] As a preferred embodiment, the crystal 10 is prismatic, and the front end of the crystal 10 slightly protrudes out of the sampling window.

[0031] Preferably, the crystal 10 is a diamond crystal, and the protrusion distance of the crystal 10 is 0-1 mm.

[0032] The use of prismatic diamond crystals and the instrument's own weight ensure that the sample and crystal can still achieve close contact without setting a press, reducing spectral signal noise.

[0033] In order to more conveniently use the infrared spectrometer of the present invention at the construction site, the present invention also discloses a technical solution for generating an optical path difference between the transmitted light and the reflected light, which can realize the miniaturization and portability of the chassis, as follows:

[0034] The infrared spectrometer of this embodiment includes a light source 1, a first parabolic reflector 2, a beam splitter 3, a first plane reflector 4, a parallel reflector group 5, a fourth plane reflector 6, a fifth plane reflector 7 and an infrared signal detector 12. The infrared light beam generated by the light source 1 is incident on the beam splitter 3 via the first parabolic reflector 2, and the beam splitter 3 divides the infrared light beam into a transmitted light and a reflected light. The reflected light returns to the beam splitter 3 via the first plane reflector 4, and the transmitted light returns to the beam splitter 3 via the parallel reflector group 5 and the fourth plane reflector 6. The beam splitter 3 merges the two returning lights.

[0035] The parallel reflector group 5 is used to make the infrared light beam produce an optical path difference that changes with the swing angle during the test. The parallel reflector group 5 includes a swing shaft 501, a second plane reflector 502 and a third plane reflector 503. The parallel reflector group 5 is connected by a connecting rod, and the swing shaft 501 is set at the center of the outer side of the second plane reflector 502. The second plane reflector 502 is parallel to the third plane reflector 503, and the second plane reflector 502 swings at a constant speed through the swing shaft 501. The swing shaft 501 rotates around its own axis, driving the parallel reflector group 5 to rotate.

[0036] Preferably, the included angle between the second plane reflector 502 and the connecting rod is 45°, and the swing angle of the swing shaft 501 is 90°, which can not only meet the volume requirement of miniaturization of the instrument, but also meet the accuracy requirement because it does not require full rotation.

[0037] The prior art usually uses parallel movement to generate optical path difference. The present invention uses a swinging parallel plane mirror group 5, which only relies on the uniform swing of the swing shaft 501 to generate the optical path difference of the infrared light beam that changes with the swing angle during the test. In comparison, rotation is the control of angular velocity, which is easier to achieve uniform speed than linear velocity control, greatly reduces the motion control accuracy requirements for the moving mirror, and has a simple structure and is easy to implement. At the same time, this solution realizes the miniaturization and portability of the spectrometer.

[0038] A reflector group is arranged in the infrared spectrometer housing 15 at a position corresponding to the sampling window. The reflector group is composed of a first reflector group 8 and a second reflector group 9. The first reflector group 8 is composed of a sixth plane reflector 801 and a second parabolic reflector 802, and the second reflector group 9 is composed of a seventh plane reflector 901 and a third parabolic reflector 902. The infrared beam reflected by the fifth plane reflector 7 passes through the sixth plane reflector 801 and the second parabolic reflector 802 successively, and then enters the sample 11 through the sampling window. The infrared beam returned from the sample 11 passes through the third parabolic reflector 902 and the seventh plane reflector 901 respectively and is acquired by the infrared signal detector 12.

[0039] The infrared signal detector 12 is connected to the data acquisition card 13 , and the collected data is converted and then transmitted to the data receiving device by the radio signal transmitter 14 .

[0040] In addition, a handle 16 is provided at the center of the rear side of the infrared spectrometer housing 15, and the handle 16 and the sampling window are respectively located on opposite sides of the infrared spectrometer housing 15. On the one hand, the handle 16 is convenient for carrying on the project site, and on the other hand, during detection, the position of the infrared spectrometer housing 15 can be adjusted by the handle 16 to accurately align the sampling window with the sample position to be detected.

[0041] The portable non-destructive testing Fourier transform infrared spectrometer disclosed in the present invention has high due value for scenes such as waterproof layers that are not suitable for sampling and testing.

[0042] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A portable non-destructive testing Fourier transform infrared spectrometer, characterized in that: The infrared spectrometer is in the shape of a box, and a sampling window is arranged on one side of the box (15) of the infrared spectrometer; the infrared light beam generated by the light source (1) is divided into transmitted light and reflected light through a beam splitter (3), and an optical path difference is formed between the transmitted light and the reflected light. Then, the infrared light beam with the optical path difference passes through a crystal (10) and enters a sample (11) from the sampling window, and the infrared light beam returned from the sample (11) is acquired by an infrared signal detector (12).

2. The infrared spectrometer according to claim 1, characterized in that The crystal (10) is prism-shaped, and one end of the prism-shaped crystal (10) protrudes out of the sampling window.

3. The infrared spectrometer according to claim 2, characterized in that The protruding distance of the crystal (10) is 0 to 1 mm.

4. The infrared spectrometer according to claim 2, characterized in that: The crystal (10) is a diamond crystal.

5. The infrared spectrometer according to claim 1, characterized in that: The infrared light beam generated by the light source (1) enters the beam splitter (3) via the first parabolic reflector (2); the reflected light returns to the beam splitter (3) via the first plane reflector (4); the transmitted light returns to the beam splitter (3) via the parallel reflector group (5) and the fourth plane reflector (6); the parallel reflector group (5) swings to cause the infrared light beam to generate an optical path difference that changes with the swing angle; the beam splitter (3) merges the two returning infrared light beams, which enter the reflector group after being reflected by the fifth plane reflector (7); The reflector group is arranged at the sampling window position; the reflector group consists of a first reflector group (8) and a second reflector group (9); the first reflector group (8) consists of a sixth plane reflector (801) and a second parabolic reflector (802); the second reflector group (9) consists of a seventh plane reflector (901) and a third parabolic reflector (902); the infrared light beam reflected by the fifth plane reflector (7) passes through the sixth plane reflector (801) and the second parabolic reflector (802) in sequence, and then enters the sample (11) through the sampling window; the infrared light beam returned from the sample (11) passes through the third parabolic reflector (902) and the seventh plane reflector (901) respectively, and is then acquired by the infrared signal detector (12).

6. The infrared spectrometer according to claim 5, characterized in that: The parallel reflector group (5) comprises a swing shaft (501), a second plane reflector (502) and a third plane reflector (503); the second plane reflector (502) and the third plane reflector (503) are connected via a connecting rod and maintained in parallel, and the swing shaft (501) is arranged at the center of the outer side of the second plane reflector (502).

7. The infrared spectrometer according to claim 6, characterized in that: The swing shaft (501) swings at a constant speed, and the swing angle is 90°.

8. The infrared spectrometer according to claim 6, characterized in that: The included angle between the second plane reflector (502) and the connecting rod is 45°.

9. The infrared spectrometer according to any one of claims 1 to 8, characterized in that: The infrared signal detector (12) is connected to a data acquisition card (13), and the data collected by the data acquisition card (13) is converted and then transmitted to the outside by a radio signal transmitter (14).

10. The infrared spectrometer according to any one of claims 1 to 8, characterized in that: A handle (16) is provided on the other side of the infrared spectrometer housing (15) opposite to the sampling window.

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