Reflection spectrum measurement light path

Abstract

The utility model discloses a reflection spectrum measurement light path, which relates to the technical field of reflection spectrum measurement, and comprises a spectrograph, an optical fiber and a reflector, illumination light emitted by a light source is irradiated on the reflector and is reflected by the reflector to enable the illumination light to irradiate vertically and downwards, a pipeline is arranged below the reflector, and the spectrograph is connected with the optical fiber. An optical fiber is arranged in the pipeline, the light inlet end of the optical fiber is located above the sample, the light outlet end of the optical fiber is connected to the spectrograph, and the optical fiber is used for collecting light carrying spectral information and diffusely reflected from the sample and transmitting the light to the spectrograph for analysis. According to the utility model, the central axis of the illumination light beam and the central axis of the acquisition cone angle coincide by installing the reflector and the corner pipeline, so that the problem that the illumination area and the spectrum acquisition area of the traditional reflection spectrum acquisition device at different working distances do not coincide is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of reflection spectrum measurement, especially to a reflection spectrum measurement light path. BACKGROUND

[0002] Reflection spectrum measurement is one of the most common applications of spectrometer, and its basic structure is that a light source irradiates an object, then a spectrometer receives the light diffusely reflected by the object, and the spectrometer analyzes the collected light.

[0003] The mainstream reflection spectrum measurement light path in the market currently mainly adopts the ways of inclined illumination and inclined collection, vertical illumination and inclined collection or inclined illumination and vertical collection, and these illumination and collection ways have two relatively large defects:

[0004] Firstly, the illumination area and the collection area cannot coincide at different working distances, and the non-coincidence of the illumination area and the collection area not only causes the waste of illumination energy, but also may cause the spectrometer to collect the information of the area not illuminated by the specified light source, thereby affecting the accuracy of the spectrum data.

[0005] Secondly, the illumination light is not uniform, and after an uniform illumination light source is inclined, the light power density on the side close to the light source is higher, and the light power density on the side far from the light source is lower.

[0006] Increasing the number of illumination light sources from different directions can increase the uniformity of the light beam to a certain extent, but it is still difficult to achieve uniform illumination of the entire illumination area in theory.

[0007] Thirdly, the placement position of the reference calibration plate is limited, and in the traditional inclined illumination or inclined collection device, because the illumination area and the spectrum collection area do not coincide, the reference calibration white plate must also be placed at the same working distance as the sample, which requires that the reference calibration plate must be larger than the sample in size.

[0008] The reference calibration plate must be at the same working distance as the sample, which results in that except for the spectrum measurement device for small samples, most devices cannot integrate the reference calibration plate in the system, thereby failing to realize the automation of collection. UTILITY MODEL CONTENT

[0009] The utility model aims to provide a reflection spectrum measurement light path, which can avoid the situation that the illumination area and the collection area cannot coincide at different working distances.

[0010] The utility model provides a reflectance spectrum measurement optical path, which includes a spectrometer, an optical fiber and a reflector. The illumination light emitted by the light source hits the reflector, and after being reflected by the reflector, the illumination light is irradiated vertically downward. A pipe is provided below the reflector, and an optical fiber is built into the pipe. The light input end of the optical fiber is located near the sample, and the light output end of the optical fiber is connected to the spectrometer. The optical fiber is used to collect light carrying spectral information diffusely reflected from the sample and transmit the light to the spectrometer for analysis.

[0011] Preferably, the reflector is a plane mirror.

[0012] Preferably, a coupling lens is installed at the lower end of the pipe, and the coupling lens is located in front of the light input end of the optical fiber. The coupling lens is used to adjust the optical fiber collection angle.

[0013] Preferably, after the coupling lens parameters are determined, a suitable coupling lens focal length is selected according to the illumination area requirements to achieve long-distance matching between the illumination beam and the collection area.

[0014] Preferably, the method further comprises installing the reflector in the pipe at an angle of 45 degrees, and placing the coupling lens in front of the reflector.

[0015] Preferably, the method further comprises placing a coupling lens behind the reflector after the reflector is installed in the pipe at an angle of 45 degrees.

[0016] Preferably, a collimating lens is installed at the lower end of the pipe, and the other end of the pipe is extended and installed with a coupling lens, and the collimating lens is located in front of a reflector obliquely installed inside the pipe.

[0017] Preferably, the illumination light is coaxial with the reflected light of the collection signal formed by the optical fiber.

[0018] Preferably, a switchable reference calibration plate is built into the bottom of the optical fiber pipeline.

[0019] Preferably, the reference calibration plate is located below the coupling lens.

[0020] Compared with the prior art, the present invention provides a reflectance spectrum measurement optical path:

[0021] 1. The present invention makes the central axis of the illumination beam coincide with the central axis of the collection cone angle by installing a reflector. As long as the focal lengths of the reflector front lens and the fiber front coupling lens are appropriately selected, the illumination angle and the collection angle can be similar or even identical. In this case, no matter how the sample is placed at a working distance, there will be no overlap between the illumination area and the collection area. This greatly extends the working distance of the reflective spectrometer and overcomes the problem of non-overlap between the illumination area and the spectrum collection area at different working distances in traditional reflective spectrum collection devices.

[0022] 2. The present invention adopts a vertical lighting method to avoid the problem of uneven lighting that occurs in oblique lighting. At the same time, the collection optical fiber is also perpendicular to the sample surface, so the problem of unevenness in oblique collection can also be avoided.

[0023] 3. The utility model makes the central axis of the illumination beam coincide with the optical axis of the collection angle, so that the two axes will not be separated at any distance. This means that we do not need to place the reference calibration plate at the sample position for collection. Instead, the reference calibration plate can be placed very close to the lens and built into the equipment, thereby realizing automatic calibration. At the same time, the placement of the reference calibration plate becomes more flexible, and it is no longer necessary to place the reference plate in the same area as the sample, thereby realizing the integration of the reference calibration plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the utility model;

[0026] Figure 2 This is a schematic diagram of the pipeline and coupling lens structure of an embodiment of the utility model;

[0027] Figure 3 This is a schematic diagram of the structure of the pipeline, coupling lens, and reflector in an embodiment of the utility model;

[0028] Figure 4 This is a schematic structural diagram of the coupling lens in an installed state according to an embodiment of the utility model;

[0029] Figure 5 This is a schematic diagram of the structure of the collimating lens and other embodiments of the present utility model;

[0030] Figure 6 This is a schematic cross-sectional view of the pipeline structure of an embodiment of the utility model;

[0031] Figure 7 This is a schematic plan view of the structure of the spectrometer, optical fiber, reflector, etc. of an embodiment of the utility model;

[0032] Figure 8 This is a schematic diagram of the coaxial state of illumination light and signal collection reflection in an embodiment of the present utility model.

[0033] Reference numerals:

[0034] 1. Spectrometer; 2. Optical fiber; 3. Reflector; 4. Pipe; 5. Reference calibration plate; 6. Coupling lens; 7. Collimating lens. DETAILED DESCRIPTION

[0035] The following embodiments of the present invention are described in detail with reference to the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0036] Example 1

[0037] Please refer to Figure 1 The embodiment of the present invention provides a reflective spectrum measurement optical path, including a spectrometer 1, an optical fiber 2 and a reflector 3. The illumination light emitted by the light source hits the reflector 3, and after being reflected by the reflector 3, the illumination light is irradiated vertically downward. The reflector 3 can be a plane mirror, a concave mirror or a convex mirror, etc. The schematic diagram takes a plane mirror as an example.

[0038] Furthermore, a pipe 4 is provided below the reflector 3, and an optical fiber 2 is built into the pipe 4. The light input end of the optical fiber 2 is located above the sample, and the light output end of the optical fiber 2 is connected to the spectrometer 1. The illumination light hits the sample to be tested, forming diffuse reflection. The diffusely reflected light carries the spectral information of the sample and enters the optical fiber 2 placed in the pipe 4, and is transmitted to the spectrometer 1 for analysis by the optical fiber 2.

[0039] Example 2

[0040] like Figure 2 As shown, a coupling lens 6 is installed at the lower end of the pipe 4. The coupling lens 6 is located in front of the light input end of the optical fiber 2. The function of the coupling lens 6 is to control the collection angle of the optical fiber 2 according to the requirements of different applications. After the parameters of the coupling lens 6 are determined, the appropriate focal length of the coupling lens 6 is selected according to the requirements of the illumination area to achieve long-distance matching between the illumination beam and the collection area, wherein the illumination light is coaxial with the reflected light of the collection signal of the optical fiber 2, which greatly enhances the working distance.

[0041] Example 3

[0042] like Figure 3 As shown, the reflector 3 is also installed in the pipe 4 at an angle of 45 degrees, and the coupling lens 6 is placed in front of the reflector 3. When collecting the light diffusely reflected from the sample, according to the actual situation of the optical fiber 2, the reflector 3 placed at a 45-degree angle can be selected to rotate the direction of the optical axis so that the illumination light and the collection signal reflected light formed by the optical fiber 2 are coaxial.

[0043] Example 4

[0044] like Figure 4As shown, after the reflector 3 is installed at a 45-degree angle in the pipe 4, the coupling lens 6 is placed behind the reflector 3. At this time, the optical fiber 2 is not bent. Through the use of the coupling lens 6 and the reflector 3, the illumination light and the collection signal reflection light formed by the optical fiber 2 are made coaxial.

[0045] Example 5

[0046] like Figures 5 to 7 As shown, a collimating lens 7 is installed at the lower end of the pipe 4. The other end of the pipe 4 is extended and equipped with a coupling lens 6. The collimating lens 7 is located in front of the reflector 3 installed obliquely inside the pipe 4. At this time, you can choose not to use the reflector 3 but directly rotate the optical fiber 2 90 degrees.

[0047] Figure 8 This is a schematic diagram of the coaxiality of the illumination light and the reflected light of the collection signal formed by the optical fiber 2. Regardless of whether the reflector 3 is used or the optical fiber 2 is directly rotated, it has a simple structure and is easy to operate, which reduces the difficulty of use for users. The above provides a variety of options through different implementation plans. Users can choose the most appropriate configuration according to actual needs, thereby enhancing the flexibility of the system.

[0048] Example 6

[0049] A switchable reference calibration plate 5 is built into the optical fiber 2 pipeline. The reference calibration plate 5 is located below the coupling lens 6 and can be switched manually or automatically.

[0050] The above is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A reflective spectrum measurement optical path, comprising a spectrometer (1), an optical fiber (2) and a reflector (3), characterized in that: The illumination light emitted by the light source hits the reflector (3), and after being reflected by the reflector (3), the illumination light is vertically irradiated downward. A pipe (4) is provided below the reflector (3), and an optical fiber (2) is built into the pipe (4). The light input end of the optical fiber (2) is located above the sample, and the light output end of the optical fiber (2) is connected to the spectrometer (1). The optical fiber (2) is used to collect light carrying spectral information diffusely reflected from the sample and transmit the light to the spectrometer (1) for analysis.

2. The reflectance spectrum measurement optical path according to claim 1, characterized in that: The reflector (3) is a plane mirror.

3. The reflectance spectrum measurement optical path according to claim 2, characterized in that: A coupling lens (6) is installed at the lower end of the pipe (4). The coupling lens (6) is located in front of the light input end of the optical fiber (2). The coupling lens (6) is used to adjust the collection angle of the optical fiber (2).

4. The reflectance spectrum measurement optical path according to claim 3, characterized in that: After the parameters of the coupling lens (6) are determined, a suitable focal length of the coupling lens (6) is selected according to the requirements of the illumination area to achieve long-distance matching between the illumination beam and the collection area.

5. The reflectance spectrum measurement optical path according to claim 4, characterized in that: The method further comprises installing the reflector (3) in the pipe (4) at an angle of 45 degrees, and placing a coupling lens (6) in front of the reflector (3).

6. The reflectance spectrum measurement optical path according to claim 5, characterized in that: The method further comprises placing a coupling lens (6) behind the reflector (3) after the reflector (3) is installed in the pipe (4) at an angle of 45 degrees.

7. The reflectance spectrum measurement optical path according to claim 6, characterized in that: The invention also includes installing a collimating lens (7) at the lower end of the pipe (4), and the other end of the pipe (4) is extended and installed with a coupling lens (6). The collimating lens (7) is located in front of a reflector (3) obliquely installed inside the pipe (4).

8. The reflectance spectrum measurement optical path according to claim 1, characterized in that: The illumination light is coaxial with the collection signal reflection light formed by the optical fiber (2).

9. The reflectance spectrum measurement optical path according to claim 8, characterized in that: A switchable reference calibration plate (5) is built-in below the optical fiber (2) pipeline.

10. The reflectance spectrum measurement optical path according to claim 9, characterized in that: The reference calibration plate (5) is located below the coupling lens (6).

Images