Raman probe with built-in calibration light source and spectrum detection device

Abstract

The invention provides a Raman probe with a built-in calibration light source. The Raman probe comprises a dichroscope, an exciting light emitting module, a calibration light generating module, a signal light input end and a signal light output end, the exciting light emitting module outputs exciting light and the exciting light is reflected to the signal light input end through the dichroscope; the calibration light emitting module outputs calibration light and the calibration light is reflected to the signal light output end through the dichroscope; the signal light input end collects signal light, transmits the signal light to the dichroscope and then transmits the signal light to the signal light output end; and the signal light output end uniformly outputs the signal light and the calibration light. The invention also provides a spectrum detection device which comprises a spectrograph and a Raman probe with a built-in calibration light source, and the spectrograph is connected with the light output end of the Raman probe and completes self-calibration through the received calibration light. According to the invention, the calibration light source is arranged in the Raman probe by using the existing detection light path element, and the calibration light source and corresponding optical components do not need to be manually debugged by depending on the reflection output of the dichroscope, so that the spectrum calibration can be efficiently completed in real time.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of spectral detection, in particular to a Raman probe with built-in calibration light source and spectral detection device. BACKGROUND

[0002] When light irradiates to medium, part of the light is scattered, including Rayleigh scattering and Raman scattering. Rayleigh scattering belongs to elastic scattering, and the photon only changes the direction of motion after colliding with the molecule, and the energy remains unchanged. Raman scattering belongs to inelastic scattering, and the photon exchanges energy with the molecule, resulting in a change in the frequency of scattered light. Raman spectroscopy is a kind of scattering spectrum, which can reflect the vibration information of the molecules of the substance, and has good chemical specificity, so it is widely used in the fields of chemistry, polymer materials, geology, life science, etc. The intensity of Raman scattering is about times of Rayleigh scattering, which is times of the intensity of incident light, so the Raman spectrometer usually has a very high detection signal-to-noise ratio.

[0003] In order to ensure the accuracy and repeatability of Raman spectroscopy, corresponding calibration work must be carried out. At present, the conventional calibration method is to add a standard spectral signal below the objective lens as a calibration light source, and through the corresponding optical path structure in the Raman spectrometer, the standard spectral signal enters the imaging spectrometer, thereby performing the corresponding subsequent calibration work. This method needs to repeatedly disassemble and assemble the calibration light source and adjust its position to maintain the consistency of the optical path once calibration is needed, which makes the calibration process complex and time-consuming.

[0004] Therefore, how to design a Raman spectrometer which is simple to operate and can be calibrated in real time has become one of the technical problems to be solved by the technical personnel in the field.

[0005] It should be noted that the above introduction to the technical background is only to facilitate the clear and complete description of the technical scheme of the present application, and to facilitate the understanding of the technical personnel in the field. The above technical scheme cannot be considered as known to the technical personnel in the field only because it is described in the background section of the present application. SUMMARY

[0006] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a Raman probe with built-in calibration light source and spectral detection device, which solves the problem of complex and time-consuming calibration of the Raman spectrometer in the prior art.

[0007] ​​To achieve the above object and other related objects, the present application provides a Raman probe with built-in calibration light source, which comprises at least a dichroic mirror, an excitation light emitting module, a signal light input end, a calibration light generating module and a signal light output end; the excitation light emitting module and the signal light input end are located at a first side of the dichroic mirror, and the calibration light generating module and the signal light output end are located at a second side of the dichroic mirror; wherein the first side and the second side of the dichroic mirror are opposite; the excitation light emitting module comprises a laser and a first filter; the laser emits excitation light, which passes through the first filter and is reflected by a first surface of the dichroic mirror to enter the signal light input end; the signal light input end comprises a signal light collector; the excitation light is transmitted along an optical axis of the signal light collector to a sample to be detected, the sample to be detected generates signal light, the signal light is collected by the signal light collector and transmitted to the dichroic mirror, and then is transmitted to the signal light output end through the dichroic mirror; the calibration light generating module comprises a calibration light source; the calibration light source generates calibration light, which is reflected by a second surface of the dichroic mirror to the signal light output end; the propagation direction of the calibration light after being reflected by the dichroic mirror is parallel to the optical axis of the signal light collector; wherein the calibration light and the signal light are in the same wave band; the signal light output end comprises a filter; the signal light and the calibration light pass through the filter to filter out stray light, and then are output to outside of the Raman probe with built-in calibration light source.

[0008] Optionally, the excitation light emitting module further comprises a collimating mirror; the collimating mirror is arranged in an optical path between the laser and the dichroic mirror, and is used for collimating the excitation light.

[0009] Optionally, the signal light collector is any one of a lens, an arc-shaped mirror or a compound parabolic concentrator.

[0010] Optionally, the calibration light generating module further comprises a light homogenizing plate; the light homogenizing plate is arranged in an optical path between the calibration light source and the dichroic mirror, and is used for homogenizing the light intensity of the calibration light and widening the spot size of the calibration light.

[0011] Optionally, the calibration light generating module further comprises a third lens; the third lens is arranged in an optical path between the calibration light source and the dichroic mirror, and is used for collimating the calibration light.

[0012] Optionally, the calibration light generating module further comprises a third filter; the third filter is arranged in an optical path between the calibration light source and the dichroic mirror, and is used for filtering out stray light in the calibration light.

[0013] Optionally, the signal light output end further comprises a second lens, which is arranged in the light path between the dichroic mirror and the filter or in the light path after the filter, and is used for coupling the signal light and the calibration light.

[0014] Optionally, the reflectivity of the second surface of the dichroic mirror to the calibration light is 1%-10%.

[0015] Optionally, the Raman probe with the built-in calibration light source further comprises a shell; the dichroic mirror, the excitation light emitting module, the signal light input end, the calibration light generating module and the signal light output end are all located in the shell; a first light transmission hole is arranged at the position of the shell corresponding to the signal light input end; a second light transmission hole is arranged at the position of the shell corresponding to the signal light output end.

[0016] To achieve the above object and other related objects, the present application further provides a spectral detection device, which at least comprises: a spectrometer and the Raman probe with the built-in calibration light source; the spectrometer is used for receiving the calibration light and the signal light output by the Raman probe with the built-in calibration light source; the spectrometer performs spectral detection based on the signal light and performs spectral calibration based on the calibration light.

[0017] Optionally, when the calibration light generating module comprises a light homogenizing sheet, the spectral detection device further comprises an optical fiber bundle; the optical fiber bundle is connected between the Raman probe with the built-in calibration light source and the spectrometer, and is used for transmitting the signal light and the calibration light output by the Raman probe with the built-in calibration light source into the spectrometer.

[0018] More optionally, the optical fiber bundle comprises n light-transmitting optical fibers and m non-light-transmitting dark cores, wherein n is a natural number greater than or equal to 1, and m is an integer greater than or equal to 0; when n is equal to 1, m is 0; when n is greater than or equal to 2, m is greater than or equal to 0; at one end of the optical fiber bundle connected to the Raman probe with the built-in calibration light source, the n light-transmitting optical fibers and the m non-light-transmitting dark cores are arranged in concentric circles; at the other end of the optical fiber bundle connected to the spectrometer, the n light-transmitting optical fibers and the m non-light-transmitting dark cores are arranged in a linear shape.

[0019] As described above, the Raman probe with the built-in calibration light source and the spectral detection device of the present application have the following beneficial effects:

[0020] 1. The present application sets the calibration light source inside the Raman probe, relies on the dichroic mirror to reflect and output, so that the Raman probe with the built-in calibration light source can efficiently and timely output the calibration light. The present application does not need to manually adjust the calibration light source which is independent of the original optical system, nor does it need to move the components in the original optical system.

[0021] 2、The present application sets the fiber bundle between the Raman probe and the spectrometer, on one hand, the Raman probe is coupled with the round end of the fiber bundle, on the other hand, the spectrometer is coupled with the linear end of the fiber bundle, thus the present application greatly improves the transmission efficiency and quality of the signal light and the calibration light between the Raman probe and the spectrometer. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The first structure diagram of the Raman probe with the built-in calibration light source of the present application.

[0023] Figure 2 The orientation diagram of the dichroic mirror of the present application.

[0024] Figure 3 The structure diagram of the calibration light generation module of the present application.

[0025] Figure 4 The second structure diagram of the Raman probe with the built-in calibration light source of the present application.

[0026] Figure 5 The first structure diagram of the spectral detection device of the present application.

[0027] Figure 6 The second structure diagram of the spectral detection device of the present application.

[0028] Figure 7 The spectral data diagram of the calibration light of each channel acquired by the spectrometer of the present application before calibration.

[0029] Figure 8 The spectral data diagram of the calibration light of each channel acquired by the spectrometer of the present application after calibration.

[0030] Figure 9 The structure diagram of the two ends of the fiber bundle of the present application.

[0031] Figure 10 The structure diagram of the first end of the fiber bundle of the present application.

[0032] Figure 11 The structure diagram of the second end of the fiber bundle of the present application.

[0033] Element Number Explanation

[0034] DETAILED DESCRIPTION

[0035] Following, specific embodiments of the present application are illustrated by way of specific examples, and other advantages and effects of the present application can be easily understood by those skilled in the art from the disclosure of the present specification. The present application can also be implemented or applied by other different specific embodiments, and various modifications or changes can be made to the details in the present specification based on different views and applications without departing from the spirit of the present application.

[0036] Please refer to Figures 1-11 It should be noted that the diagrams provided in the present embodiment only schematically illustrate the basic concept of the present application, and thus only the components related to the present application are shown in the diagrams, rather than being drawn according to the number, shape and size of the components in actual implementation. The actual implementation of each component may be arbitrarily changed in terms of shape, number and ratio, and the layout pattern of the components may also be more complex.

[0037] After the Raman light enters the spectrometer, there is a significant spectral drift problem of the Raman light in each channel, which will lead to an undesirable detection result of the spectrometer, and thus the spectrometer needs to be calibrated. Adding a calibration light source in the Raman spectrometer is a conventional idea, but as described in the background art, the conventional idea has the disadvantages of complexity and time-consuming, because the signal acquisition light path structure in the spectrometer is already fixed, and the addition of an external calibration light source needs to be constantly debugged to maintain the consistency of the signal acquisition light path during calibration. The improvement idea is put into the entire imaging spectrometer device, and since the Raman probe has the advantages of simple structure and flexible modification, the calibration light source can be set in the Raman probe, but adding the calibration light source in the Raman probe also has the problem of needing to debug the movable elements.

[0038] Therefore, in order to solve the above problems, the present application proposes a Raman probe with a built-in calibration light source and a spectrum detection device, and the specific technical solutions are as follows:

[0039] Embodiment one

[0040] As shown in Figure 1 , the present embodiment provides a Raman probe 1 with a built-in calibration light source, which comprises a dichroic mirror 15, an excitation light emitting module 11, a signal light input end 12, a calibration light generating module 13 and a signal light output end 14.

[0041] As shown in Figure 1 , the excitation light emitting module 11 and the signal light input end 12 are located on the first side of the dichroic mirror 15, and the calibration light generating module 13 and the signal light output end 14 are located on the second side of the dichroic mirror 15; wherein the first side and the second side of the dichroic mirror 15 are opposite.

[0042] Specifically, in the present embodiment, as shown in Figure 2As shown, in order to meet the reflection of excitation light, the transmission of signal light and the reflection of calibration light, on the one hand, the excitation light emitting module 11 and the signal light input end 12 are located on one side of the dichroic mirror 15, and the calibration light generating module 13 and the signal light output end 14 are located on the other side of the dichroic mirror 15; on the other hand, the light emitted by the excitation light emitting module 11 and the calibration light generating module 13 are parallel to the first direction, and the signal light path between the signal light input end 12 and the signal light output end 14 is parallel to the second direction, and the first direction and the second direction are axially symmetric about the normal line of the dichroic mirror 15, and the included angle with the dichroic mirror 15 is greater than 0 degrees and less than 90 degrees, including but not limited to 15 degrees, 30 degrees, 45 degrees, 60 degrees and 75 degrees. , Further, by selecting a suitable dichroic mirror 15, the dichroic mirror 15 reflects the signal light in the excitation light band and transmits the signal light in the target signal light band. In actual application, different wave bands of dichroic mirror 15 are selected according to needs, which will not be specifically described here.

[0043] As shown in the embodiment, Figure 1 The excitation light emitting module 11 includes a laser 1a and a first optical filter 1c, the laser 1a emits excitation light, the excitation light passes through the first optical filter 1c and is reflected by the first surface of the dichroic mirror 15 into the signal light input end 12.

[0044] Specifically, in the embodiment, as shown in the embodiment, Figure 1 The excitation light emitted by the laser 1a is transmitted to the first optical filter 1c, the first optical filter 1c is used to filter out stray light in the excitation light, and the purified excitation light is transmitted to the first surface of the dichroic mirror 15 and reflected by the first surface of the dichroic mirror 15 to the signal light input end 12. Further, as shown in the embodiment, Figure 1 The excitation light emitting module 11 further includes a collimating mirror 1b, which is arranged in the light path between the laser 1a and the dichroic mirror 15 and is used to collimate the excitation light. As an example, the laser 1a is selected from any one of a solid-state laser, a gas laser and a semiconductor laser, and the first optical filter 1c is selected from a band-pass optical filter with a center wavelength equal to the wavelength of the excitation light. In actual application, the specific types of the laser 1a and the first optical filter 1c are selected according to needs, which are not limited to the embodiment.

[0045] As shown in the embodiment, Figure 1 The signal light input end 12 includes a signal light collector 1d; the excitation light is transmitted to the sample to be detected along the optical axis of the signal light collector 1d, the sample to be detected generates signal light under excitation, the signal light is collected by the signal light collector 1d and transmitted to the dichroic mirror 15, and then transmitted to the signal light output end 14 through the dichroic mirror 15.

[0046] Specifically, in the embodiment, as shown in the embodiment, Figure 1As shown in the figure, the excitation light is transmitted to the surface of the sample to be detected through the optical axis of the signal light collector 1d, the sample to be detected is excited and generates Raman signal light, since the signal light is scattered by the sample to be detected, the signal light needs to be collected by the signal light collector 1d, and based on the transmission of the dichroic mirror 15 to the target waveband, the signal light is transmitted to the signal light output end 14 through the dichroic mirror 15. As an example, the signal light collector 1d is any one of a lens, a curved mirror or a compound parabolic concentrator, which is used to collimate or focus the Raman signal light. In actual application, the specific type of the signal light collector 1d is set according to the need, which is not limited by the embodiment.

[0047] As shown in the figure, Figure 1 and Figure 3 The calibration light generating module 13 includes a calibration light source 1e, which generates calibration light. The calibration light is reflected by the second surface of the dichroic mirror 15 to the signal light output end 14. After being reflected by the dichroic mirror 15, the propagation direction of the calibration light is parallel to the optical axis of the signal light collector 1d. The calibration light and the signal light are in the same waveband.

[0048] Specifically, in the embodiment, the calibration light is reflected by the second surface of the dichroic mirror 15 to the signal light output end 14. The calibration light source 1e is a standard spectral signal added in the Raman probe 1, which is used to calibrate the spectral data of the signal light obtained by the spectrometer 2. Since the calibration light generated by the calibration light source 1e and the excitation light generated by the laser 1a are both in the first direction, the reflected calibration light is parallel to the signal light. Further, as shown in the figure, Figure 3 The calibration light generating module 13 also includes a light homogenizing plate 1h, which is arranged in the optical path between the calibration light source 1e and the dichroic mirror 15, and is used to uniform the light intensity of the calibration light and widen the spot size of the calibration light. The calibration light generating module 13 also includes a third lens 1g, which is arranged in the optical path between the calibration light source 1e and the dichroic mirror 15, and is used to collimate the calibration light. The calibration light generating module 13 also includes a third filter 1f, which is arranged in the optical path between the calibration light source 1e and the dichroic mirror 15, and is used to filter out stray light in the calibration light. The stray light refers to the light signal outside the waveband of the calibration light and the signal light. Further, as shown in the figure, Figure 3 When the calibration light generating module 13 includes the light homogenizing plate 1h, the third lens 1g and the third filter 1f, the third lens 1g and the third filter 1f should be arranged in the optical path after the light homogenizing plate 1h. As an example, when the wavelength of the excitation light generated by the laser 1a is 785 nm, the waveband of the signal light is about 800-930 nm, and the calibration light source 1e selects a NeAr lamp whose main spectrum is also located in the waveband of 800-930 nm, the third filter 1f adopts a long-pass filter with a cutoff wavelength of 800 nm. In actual application, the specific types of the calibration light source 1e and the third filter 1f are selected according to the need, which are not limited by the embodiment.

[0049] As shown in Figure 1 , the signal light output end 14 comprises a filter 1j, and the signal light and the calibration light pass through the filter 1j to filter out stray light, and then are output to the Raman probe 1 with the built-in calibration light source.

[0050] Specifically, in the embodiment, as shown in Figure 1 , the filter 1j receives the signal light and the calibration light, and is used to filter out the excitation light mixed therein, and the signal light and the calibration light pass through the filter 1j and then are output to the Raman probe 1, and as an example, the filter 1j can be selected as a long-pass filter, and in actual application, a specific type of filter 1j is selected according to the needs, which is not limited to the embodiment. Further, the signal light output end 14 further comprises a second lens 1i, which is arranged in the optical path between the dichroic mirror 15 and the filter 1j or in the optical path after the filter 1j, and is used to couple the signal light and the calibration light, and the second lens 1i can be selected as any one of a lens for reducing the divergence angle, a collimating lens and a focusing lens, which is not specifically described herein.

[0051] Specifically, in the embodiment, as shown in Figure 4 , the Raman probe 1 with the built-in calibration light source further comprises a housing 16, and the dichroic mirror 15, the excitation light emitting module 11, the signal light input end 12, the calibration light generating module 13 and the signal light output end 14 are all located in the housing 16; wherein the housing 16 is made of light-proof material, and can shield the internal optical system from external stray light. Further, in order to output the excitation light to the sample to be detected and collect the signal light of the sample to be detected, the signal light optical path should be provided with a first light transmission hole 1m at the position of the housing corresponding to the side of the signal light input end 12, and in order to output the signal light and the calibration light, the signal light optical path and the calibration light optical path should be provided with a second light transmission hole 1n at the position of the housing corresponding to the side of the signal light output end 14.

[0052] It should be noted that since the calibration light and the signal light are in the same waveband, the dichroic mirror 15 mainly transmits the signal light and the calibration light in the target waveband. Generally, the higher the transmittance of the dichroic mirror in the target waveband, the better. In a conventional case, the dichroic mirror needs to be coated with an anti-reflection film to make its transmittance in the target signal light waveband reach 99% or more, which means that its reflectance is less than 1%. However, in order to avoid the trouble of constantly adjusting the calibration light source 1e as an independent optical element, the embodiment reverses the process, using a specially designed dichroic mirror 15 or a dichroic mirror 15 without an anti-reflection film, which has a small but non-negligible reflectance in the target signal light waveband, i.e. the reflectance of the second surface of the dichroic mirror 15 to the calibration light is 1%-10%, including but not limited to 3%, 5%, 7%, 9%. In actual application, the reflectance of the second surface of the dichroic mirror 15 to the calibration light is set according to the needs, not limited to the embodiment. The calibration light source 1e is placed on the second side of the dichroic mirror 15, and the small reflectance of the second surface of the dichroic mirror 15 to the calibration light is used to transmit the calibration light to the spectrometer 2 to calibrate the spectrometer 2, so that the Raman probe can output signal light and calibration light at the same time. On the other hand, the low reflectance may cause the calibration light to be too weak, which can be solved by increasing the light intensity of the calibration light source 1e or prolonging the detection integration time, thereby achieving the purpose of the embodiment of simple operation and real-time calibration of the spectrometer 2.

[0053] It should be further noted that the Raman probe 1 with a built-in calibration light source in the embodiment not only completes the task of exciting and outputting signal light, but also completes the task of outputting calibration light with the help of existing optical elements. It does not need to manually separate the calibration light source 1e from the original Raman probe 1 optical system or the spectrometer 2 optical system, nor does it need to move the components in the corresponding optical system. It has the advantages of simple structure and high system integration.

[0054] Embodiment Two

[0055] As shown in Figure 5 , the embodiment provides a spectrum detection device, which includes a spectrometer 2 and a Raman probe 1 with a built-in calibration light source. The spectrometer 2 is used to receive the calibration light and the signal light output by the Raman probe 1 with a built-in calibration light source. The spectrometer 2 performs spectrum detection based on the signal light and performs spectrum calibration based on the calibration light.

[0056] Specifically, in the embodiment, since the Raman probe 1 outputs signal light and calibration light at the same time, the spectrometer 2 calibrates the obtained signal light spectrum in real time. Further, as shown in Figure 5 , the spectrometer 2 can be directly located behind the optical path of the Raman probe 1 and receive the signal light and the calibration light through spatial light transmission. As shown in Figure 6 , the spectrometer 2 can also receive the calibration light and the signal light output by the Raman probe 1 through the optical fiber bundle 3. As an example, as shown inFigure 7 As shown in FIG. 6, the spectrum in the spectrum diagram of the calibration light obtained by the spectrometer 2 has a more obvious drift, and as shown in FIG. 7, the spectrum drift in the spectrum diagram of the calibration light obtained by the spectrometer 2 based on the Raman probe 1 with the built-in calibration light source of the present embodiment is greatly improved, and the same applies to the spectrum data of the signal light obtained by the spectrometer 2 of the present embodiment, which will not have an obvious drift, and the result of the Raman light detection will be more accurate. Figure 8 As shown in FIG. 6, the spectrum in the spectrum diagram of the calibration light obtained by the spectrometer 2 has a more obvious drift, and as shown in FIG. 7, the spectrum drift in the spectrum diagram of the calibration light obtained by the spectrometer 2 based on the Raman probe 1 with the built-in calibration light source of the present embodiment is greatly improved, and the same applies to the spectrum data of the signal light obtained by the spectrometer 2 of the present embodiment, which will not have an obvious drift, and the result of the Raman light detection will be more accurate.

[0057] Specifically, in the present embodiment, when the calibration light generating module 13 includes the light homogenizing sheet 1h, the spectrum detection device further includes the fiber bundle 3, since the light homogenizing sheet 1h can expand the light beam of the calibration light, so that the calibration light output by the Raman probe 1 can match the size of the fiber bundle 3. Further, the fiber bundle 3 is connected between the Raman probe 1 and the spectrometer 2, and is used to transmit the signal light and the calibration light output by the Raman probe 1 to the spectrometer 2, since the fiber bundle 3 can not only transmit the light signal but also perform spatial filtering, therefore, the transmission quality and transmission efficiency of the signal light and the calibration light can be greatly improved. Still further, the fiber bundle 3 includes n light-transmitting optical fibers 3a and m non-light-transmitting dark cores 3b, in order to better protect the fiber bundle 3, each light-transmitting optical fiber 3a and each non-light-transmitting dark core 3b can be wrapped by a non-light-transmitting cladding 3c; wherein n is a natural number greater than or equal to 1, and m is an integer greater than or equal to 0. As an example, when n is equal to 1, m is 0, that is, there is one light-transmitting optical fiber 3a connected between the Raman probe 1 and the spectrometer 2. As another example, when n is greater than or equal to 2, m is greater than or equal to 0, such as Figure 9 、 Figure 10 and Figure 11 As shown in FIG. 8, in order to adapt to the shape of the Raman light, at the end of the fiber bundle 3 connected to the Raman probe 1 (the first end of the fiber bundle 3), the n light-transmitting optical fibers 3a and the m non-light-transmitting dark cores 3b are arranged in concentric circles, the offset of the signal light at the center of the circle is 0, and the offsets of the signal light on the same circle are equal; in order to adapt to the shape of the entrance slit of the spectrometer 2, at the end of the fiber bundle 3 connected to the spectrometer 2 (the second end of the fiber bundle 3), the n light-transmitting optical fibers 3a and the m non-light-transmitting dark cores 3b are arranged in a linear shape, and the non-light-transmitting dark cores 3b separate the light-transmitting optical fibers 3a with different offsets such as zero offset, first offset and second offset in the linear arrangement. In actual application, the specific arrangement shape of the fiber bundle 3 can be set as needed, which is not limited by the present embodiment.

[0058] In summary, the Raman probe with built-in calibration light source of the present application comprises a dichroic mirror, an excitation light emitting module, a signal light input end, a calibration light generating module and a signal light output end; the excitation light emitting module emits excitation light, which is reflected by the first surface of the dichroic mirror and then enters the signal light input end; the signal light input end generates signal light, which is transmitted by the dichroic mirror and then enters the signal light output end; the calibration light generating module generates calibration light, which is reflected by the second surface of the dichroic mirror and then enters the signal light output end; and the signal light output end outputs the signal light and the calibration light together to outside of the Raman probe with built-in calibration light source. The spectral detection device of the present application comprises a spectrometer and a Raman probe with built-in calibration light source; the spectrometer receives the calibration light and the signal light output by the Raman probe; the spectrometer performs spectral detection based on the signal light and completes self-spectral calibration based on the calibration light. The Raman probe with built-in calibration light source of the present application utilizes the existing detection optical path components, sets the calibration light source inside the Raman probe, and outputs the calibration light by reflection of the dichroic mirror, so that the spectral detection device of the present application does not need to manually adjust the calibration light source which is independent of the original Raman probe optical system and the spectrometer optical system, and does not need to move the components in the original optical system, and can efficiently and timely complete the purpose of self-spectral calibration, and has the advantages of low cost, simple operation and high system integration. Therefore, the present application effectively overcomes the various shortcomings in the prior art and has high industrial utilization value.

[0059] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not used to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes completed by those skilled in the art without departing from the spirit and technical thought disclosed by the present application should be covered by the claims of the present application.

Claims

1. A Raman probe with a built-in calibration light source, characterized in that, The Raman probe with built-in calibration light source includes at least: a dichroic mirror, an excitation light emission module, a signal light input terminal, a calibration light generation module, and a signal light output terminal; The excitation light emission module and the signal light input terminal are located on the first side of the dichroic mirror, and the calibration light generation module and the signal light output terminal are located on the second side of the dichroic mirror; wherein the first side and the second side of the dichroic mirror are opposite to each other; The excitation light emitting module includes a laser and a first filter; the laser emits excitation light, which passes through the first filter and is then reflected by the first surface of the dichroic mirror into the signal light input terminal; The signal light input terminal includes a signal light collector; the excitation light is transmitted to the sample to be tested along the optical axis of the signal light collector, the sample to be tested is excited to generate signal light, the signal light is collected by the signal light collector and transmitted to the dichroic mirror, and then transmitted to the signal light output terminal through the dichroic mirror. The calibration light generation module includes a calibration light source; the calibration light source generates calibration light, which is reflected by the second surface of the dichroic mirror to the signal light output terminal; the direction of propagation of the calibration light after reflection by the dichroic mirror is parallel to the optical axis of the signal light collector; wherein, the calibration light and the signal light are in the same wavelength band. The signal light output terminal includes a filter; the signal light and the calibration light pass through the filter to remove stray light, and are then jointly output to the Raman probe of the built-in calibration light source.

2. The Raman probe with a built-in calibration light source according to claim 1, characterized in that: The excitation light emitting module also includes a collimating lens; the collimating lens is disposed in the optical path between the laser and the dichroic mirror, and is used to collimate the excitation light.

3. The Raman probe with a built-in calibration light source according to claim 1, characterized in that: The signal light collector is any one of a lens, an arc-shaped mirror, or a compound parabolic surface condenser.

4. The Raman probe with a built-in calibration light source according to claim 1, characterized in that: The calibration light generation module also includes a light homogenizer; the light homogenizer is disposed in the optical path between the calibration light source and the dichroic mirror, and is used to homogenize the light intensity of the calibration light and widen the light spot size of the calibration light.

5. The Raman probe with a built-in calibration light source according to claim 1, characterized in that: The calibration light generation module further includes a third lens; the third lens is disposed in the optical path between the calibration light source and the dichroic mirror, and is used to collimate the calibration light.

6. The Raman probe with a built-in calibration light source according to claim 1, characterized in that: The calibration light generation module further includes a third filter; the third filter is disposed in the optical path between the calibration light source and the dichroic mirror, and is used to filter out stray light in the calibration light.

7. The Raman probe with a built-in calibration light source according to claim 1, characterized in that: The signal light output terminal also includes a second lens, which is disposed in the optical path between the dichroic mirror and the filter or in the optical path after the filter, for coupling the signal light and the calibration light.

8. The Raman probe with a built-in calibration light source according to any one of claims 1-7, characterized in that: The second surface of the dichroic mirror has a reflectivity of 1%-10% for the calibration light.

9. The Raman probe with a built-in calibration light source according to any one of claims 1-7, characterized in that: The Raman probe with built-in calibration light source also includes a housing; The dichroic mirror, the excitation light emission module, the signal light input terminal, the calibration light generation module, and the signal light output terminal are all located inside the housing; The optical path of the signal light is provided with a first light-transmitting hole at the housing position corresponding to the signal light input end; the optical paths of the signal light and the calibration light are provided with a second light-transmitting hole at the housing position corresponding to the signal light output end.

10. A spectral detection device, characterized in that, The spectral detection device includes at least: a spectrometer and a Raman probe with a built-in calibration light source as described in any one of claims 1-9; The spectrometer is used to receive calibration light and signal light output from the Raman probe of the built-in calibration light source; the spectrometer performs spectral detection based on the signal light and spectral calibration based on the calibration light.

11. The spectral detection device according to claim 10, characterized in that: When the calibration light generation module includes a homogenizer, the spectral detection device further includes an optical fiber bundle; the optical fiber bundle is connected between the Raman probe of the built-in calibration light source and the spectrometer, and is used to transmit the signal light and calibration light output by the Raman probe of the built-in calibration light source to the spectrometer.

12. The spectral detection device according to claim 11, characterized in that: The fiber bundle includes n transparent optical fibers and m opaque dark cores, where n is a natural number greater than or equal to 1 and m is an integer greater than or equal to 0. When n equals 1, m takes the value 0; When n is greater than or equal to 2, m is greater than or equal to 0; at one end of the fiber bundle connected to the Raman probe of the built-in calibration light source, n transparent fibers and m opaque dark cores are arranged in concentric circles; at one end of the fiber bundle connected to the spectrometer, n transparent fibers and m opaque dark cores are arranged in a linear shape.

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