Compact hyperspectral light source structure

Abstract

The utility model provides a compact hyperspectral light source structure, and designs a novel light source structure aiming at the requirement of spectrum uniformity in an LED hyperspectral imaging system so as to overcome the limitation of the traditional light guide tube design. The structure comprises a light tube, a single-color LED light source and a diffuse reflection plate. The light tube is a cuboid shell with two open ends, the diffuse reflection plate is located at one end, the monochromatic LED light source is arranged on the edge of the inner wall of the other end, wavelengths are different, and the half-width of adjacent wavelengths is overlapped. The structure further comprises a controller and a digital-to-analog conversion module which are used for controlling on-off and brightness of the LED light source. The spectral range of the monochromatic LED light source is 400-1000 nanometers, and the device is suitable for hyperspectral measurement of fruits. By increasing the light path length and the scattering degree, the light field uniformity is improved, and meanwhile the spectral resolution and the number of light sources are guaranteed. The design overcomes the defects of a traditional light guide pipe structure, is suitable for an industrial production environment with a limited space, and improves the uniform emission and spectral selectivity of light.

Description

Technical Field

[0001] The utility model relates to a compact hyperspectral light source structure, belonging to the technical field of hyperspectral technology. Background Art

[0002] To ensure spectral uniformity in LED hyperspectral imaging systems, all LEDs must provide consistent and uniform illumination on the target plane. Traditional light pipe designs, such as those in Chinese Patent 2020226295306 (An Optical Device for Uniform Flux and Hyperspectral Selective Illumination), utilize a light source installed within one section of a square light pipe. Multiple reflections of the light source within the pipe allow uniform illumination from the other end. This design requires a light guide length-to-width ratio of at least 1:6 to ensure sufficient light diffusion and uniform light emission. This results in an overly large light pipe structure, making it unsuitable for industrial production environments with limited space. Summary of the Invention

[0003] The technical problem to be solved by the utility model is to provide a compact high-spectrum light source structure to overcome the deficiencies of the prior art.

[0004] The technical solution of the utility model is: a compact hyperspectral light source structure, which includes a light pipe, a monochromatic LED light source and a diffuse reflection plate;

[0005] The light tube is a rectangular shell with openings at both ends. The diffuse reflection plate is arranged on the opening at one end of the light tube. The monochromatic LED light source includes one or more, each monochromatic LED light source has a different wavelength, and the monochromatic LED light source is arranged on the inner wall edge of the other end opening opposite to the diffuse reflection plate.

[0006] Furthermore, the inner wall edge of the opening at the other end opposite to the diffuse reflection plate is provided with an annular rib, and the monochromatic LED light source is arranged on the annular rib so that the monochromatic LED light source is located in the inner cavity of the light tube.

[0007] Furthermore, the half-widths of the wavelengths of two monochromatic LED lamps with adjacent wavelengths in the monochromatic LED light source overlap.

[0008] Furthermore, it also includes a controller and a digital-to-analog conversion module;

[0009] The controller is used to input a switch control signal and an intensity signal of each monochromatic LED light source;

[0010] The digital-to-analog conversion module is electrically connected to the controller and is used to convert the digital signal of the controller into an analog signal that matches the monochromatic LED light source.

[0011] Furthermore, the included angle between the central axis of one side of the illumination surface of the monochromatic LED light source and the inner wall of the light tube is an acute angle.

[0012] Furthermore, the spectrum range of the monochromatic LED light source is 400-1000 nanometers.

[0013] The beneficial effects of the present invention are: compared with the prior art,

[0014] 1) The present invention uses one or more monochromatic LED light sources to emit light of different wavelengths. A portion of the light is reflected by the inner wall of the light pipe until it reaches a diffuse reflector. After reaching the diffuse reflector, the light from the light source is scattered in all directions, increasing the light propagation range. These scattered light rays are then reflected by the walls of the light pipe cavity until they are emitted from the outlet at the end where the monochromatic LED light source is located. Another portion of the light from the light source is directly reflected by the diffuse reflector, causing the light from the light source to be scattered in all directions. This portion of the scattered light rays is then reflected by the walls of the light pipe cavity until they are emitted from the outlet at the end where the monochromatic LED light source is located. Compared with traditional light pipe structures, the optical path length of the light reflected within the light pipe of this patent is doubled, increasing the optical path length and the degree of scattering. As a result, under the same aspect ratio of the light pipe structure, the emitted light field of this patent is more uniform than that of traditional light pipe structures.

[0015] 2) The present invention achieves sufficient resolution of the spectrum emitted by the device while ensuring that a sufficient number of monochromatic LED light sources can be arranged within the same spectral range by overlapping the half-widths at half-maximum of the wavelengths of two monochromatic LED lights with adjacent wavelengths in the monochromatic LED light source;

[0016] 3) The utility model generates signals through the controller to control the digital-to-analog conversion module to generate analog signals to control the switching and brightness of the monochromatic LED light source, thereby enabling the device to produce uniform light output of a specific wavelength;

[0017] 4) The present invention makes the angle between the central axis of the illumination surface of the monochromatic LED light source and the inner wall of the light pipe acute, thereby increasing the angle between the monochromatic LED light source and the light pipe wall. This causes a larger portion of the monochromatic LED light source to be reflected from the light pipe before being reflected by the diffuse reflector, reducing the portion of light directly irradiated by the diffuse reflector. This increases the optical path and scattering degree of most monochromatic LED light sources, further improving the uniformity of light output under the same aspect ratio of the light pipe structure.

[0018] 5) The utility model sets the spectral range of the monochromatic LED light source to 400-1000 nanometers, making the utility model suitable for hyperspectral measurement of fruits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural diagram of the utility model;

[0020] Figure 2 This is the principle diagram of the utility model;

[0021] Figure 3 This is the wavelength distribution diagram of the monochromatic LED light source of the utility model;

[0022] Figure 4 This is a circuit structure diagram of the utility model. DETAILED DESCRIPTION

[0023] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0024] Implementation Example 1: Reference Figure 1 , a compact hyperspectral light source structure, the structure includes a light pipe 1, a monochromatic LED light source 3 and a diffuse reflection plate 2;

[0025] The light tube 1 is a rectangular shell with openings at both ends. The diffuse reflection plate 2 is arranged on the opening at one end of the light tube 1. The monochromatic LED light source 3 includes one or more, each monochromatic LED light source 3 has a different wavelength, and the monochromatic LED light source 3 is arranged at the inner wall edge of the other end opening opposite to the diffuse reflection plate 2.

[0026] Through the above design, the optical path in the present invention is extended due to the reflection of the diffuse reflection plate 2. Figure 2 As you can see, the actual size of the light pipe 1 is L, but because the light path reflected by the diffuse reflector 2 is extended to 2L, the theoretical position of the reflector is located at the mirror image position of the actual test plate due to the extended light path. Therefore, for the same size, the optical path from the light source to the light outlet is longer.

[0027] In order to facilitate the installation of the monochromatic LED light source 3 and avoid light leakage at the installation point of the monochromatic LED light source 3, this embodiment also includes a ring-shaped rib 4 on the inner wall edge of the opening at the other end opposite to the diffuse reflection plate 2. The monochromatic LED light source 3 is arranged on the ring-shaped rib 4 so that the monochromatic LED light source 3 is located in the inner cavity of the light tube 1.

[0028] In order to ensure that the spectrum has sufficient resolution while ensuring that enough monochromatic LED light sources 3 can be set in the same spectral range, the half-widths of the wavelengths of two monochromatic LED lights with adjacent wavelengths in the monochromatic LED light source 3 overlap. The wavelengths of the monochromatic LED light source 3 are set as follows: Figure 3 shown.

[0029] In order to facilitate the control of the monochromatic LED light source 3, refer to Figure 4 , also includes a controller 6 and a digital-to-analog conversion module 7; the controller 6 is used to input the switch control signal and intensity signal of each monochromatic LED light source 3; the digital-to-analog conversion module 7 is electrically connected to the controller 6, and is used to convert the digital signal of the controller 6 into an analog signal that matches the monochromatic LED light source 3.

[0030] In order to further increase the uniformity of light output, the included angle between the central axis of the illumination surface of the monochromatic LED light source 3 and the inner wall of the light pipe 1 is an acute angle.

[0031] In order to be used for hyperspectral observation of fruits, the spectral range of the monochromatic LED light source 3 is 400-1000 nanometers.

[0032] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A compact hyperspectral light source structure, characterized in that: The structure comprises a light pipe (1), a monochromatic LED light source (3) and a diffuse reflection plate (2); The light pipe (1) is a rectangular parallelepiped shell with openings at both ends; the diffuse reflection plate (2) is arranged on an opening at one end of the light pipe (1); the monochromatic LED light source (3) comprises one or more, each monochromatic LED light source (3) having a different wavelength; and the monochromatic LED light source (3) is arranged on the inner wall edge of the other opening opposite to the diffuse reflection plate (2).

2. The compact hyperspectral light source structure according to claim 1, characterized in that: The invention also includes an annular rib (4) provided on the inner wall edge of the opening at the other end opposite to the diffuse reflection plate (2), and a monochromatic LED light source (3) is arranged on the annular rib (4) so ​​that the monochromatic LED light source (3) is located in the inner cavity of the light pipe (1).

3. The compact hyperspectral light source structure according to claim 1, characterized in that: The half-widths of wavelengths of two monochromatic LED lights with adjacent wavelengths in the monochromatic LED light source (3) overlap.

4. The compact hyperspectral light source structure according to claim 1, characterized in that: It also includes a controller (6) and a digital-to-analog conversion module (7); The controller (6) is used to input a switch control signal and an intensity signal of each monochromatic LED light source (3); The digital-to-analog conversion module (7) is electrically connected to the controller (6) and is used to convert the digital signal of the controller (6) into an analog signal that matches the monochromatic LED light source (3).

5. The compact hyperspectral light source structure according to claim 1, characterized in that: The included angle between the central axis of one side of the illumination surface of the monochromatic LED light source (3) and the inner wall of the light tube (1) is an acute angle.

6. The compact hyperspectral light source structure according to claim 1, characterized in that: The spectrum range of the monochromatic LED light source (3) is 400-1000 nanometers.

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