LED optical fiber coupling system with high NA value

Abstract

The utility model discloses an LED optical fiber coupling system with a high NA value, and relates to the technical field of optical fiber coupling. The system comprises a first lens, a second lens and a third lens which are sequentially and coaxially arranged from front to back. The first lens is an aspheric plano-convex lens L1, the second lens is an aspheric plano-convex lens L2, and the third lens is a plano-convex lens L3. Meanwhile, f1lt is met; f2lt; f2lt; f1 is the focal length of the first lens, f2 is the focal length of the second lens, and f3 is the focal length of the third lens. The LED optical fiber coupling system provided by the utility model can avoid the loss of light rays and ensure that high-efficiency coupled light beams enter the optical fiber, thereby effectively improving the illumination efficiency of a microscopic system.

Description

Technical Field

[0001] The utility model relates to the technical field of optical fiber coupling, and particularly relates to a high-NA LED optical fiber coupling system. Background Art

[0002] With the rapid development of the semiconductor industry, the microscopic system is also constantly updated and iterated. Since the microscopic system needs illumination during microscopic imaging, in recent years, various requirements have been put forward for the illumination of the microscopic system. Such as luminous efficiency, usage cost, and color system are all important parameters for evaluating the performance of the illumination system.

[0003] Luminous efficiency is the top priority of lighting technology, but the utilization rate of the light source in the microscopic system is low. The reasons often involve the parameters of the lens and the optical fiber. The numerical aperture (NA) of the optical fiber in the microscopic system is the sine product of the refractive index (n) of the medium between the front lens of the objective and the object to be inspected and half of the aperture angle (2α), and it is an important indicator for judging the performance of the lens. However, due to the limitation of the light collection angle of the system and the optical fiber material, the size of the numerical aperture of the optical fiber is restricted, resulting in the defect that the microscopic system cannot ensure its illumination efficiency. Summary of the Utility Model

[0004] Aiming at the technical problems of low light source utilization rate and inability to ensure illumination efficiency in the existing microscopic system, the present application proposes a high-NA LED optical fiber coupling system, which can achieve efficient aggregation of light beams and improve the optical fiber coupling efficiency and the luminous efficiency of the microscopic system.

[0005] The technical solution adopted by the utility model is as follows:

[0006] A high-NA LED optical fiber coupling system is proposed, including a first lens, a second lens, and a third lens; the first lens is an aspherical plano-convex lens L1, the second lens is an aspherical plano-convex lens L2, and the third lens is a plano-convex lens L3; the focal length of the first lens is f1, the focal length of the second lens is f2, and the focal length of the third lens is f3, where f1 < f2 < f3. The type and focal length of the lens provide a certain condition basis for maximizing the beam coupling efficiency.

[0007] Further, the thickness from the front end face to the rear end face of L1 is 14 mm to 15 mm, the thickness from the front end face to the rear end face of L2 is 25 mm to 28 mm, and the thickness from the front end face to the rear end face of L3 is 15 mm to 18 mm. By controlling the optical thickness of the lens, the propagation path of the light beam is optimized, and the transmission efficiency and stability of the optical fiber coupling system are improved.

[0008] Further, the curvature radius of the light-emitting surface of the aspherical plano-convex lens L1 facing away from the lamp bead is -10 mm to -12 mm.

[0009] Further, the radius of curvature of the aspherical plano-convex lens L2 on the light-emitting surface facing away from the lamp bead is -18 mm to -20 mm.

[0010] Further, the radius of curvature of the light-receiving surface of the plano-convex lens L3 facing the lamp bead is 24 mm to 26 mm. By adjusting the radius of curvature of the lens, the focusing effect and divergence of the light beam are achieved, thereby further optimizing the performance of the fiber optic coupling system.

[0011] Further, the materials of the first lens and the second lens are B270 glass.

[0012] Further, the material of the third lens is H-K9L glass. Only two materials are used in this coupling system, and the material procurement is relatively simple.

[0013] Further, the first lens, the second lens, and the third lens are coaxially arranged in sequence along the direction of the light beam emitted by the lamp bead. The first lens, the second lens, and the third lens efficiently converge the light beam, and the light collection rate is high, so as to be transmitted to the optical terminal through the optical fiber.

[0014] Further, the system is arranged between the object plane and the image plane, the object plane is the surface of the lamp bead, and the image plane is the surface of the optical fiber.

[0015] Further, the numerical aperture NA of the optical fiber is greater than or equal to 0.516. When the spectral range is within 400 nm to 700 nm, the fiber coupling efficiency of each wavelength is as high as 100%.

[0016] The beneficial effects of the LED fiber optic coupling system provided by this application are as follows:

[0017] The object space NA value of the LED fiber optic coupling system provided by the present utility model is 0.866, that is, the light collection angle of this system can reach 120°. When calculating the fiber coupling efficiency using an optical fiber with an NA value of 0.52 for transmission, the fiber coupling efficiency of each wavelength within the spectral range of 400 nm to 700 nm is as high as 100%. This system collects light to the maximum extent, tries to avoid light loss, and ensures that the highly efficient coupled light beam enters the optical fiber. Its light collection performance and optical effect are both excellent. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the high-NA value LED fiber optic coupling system described in the present utility model.

[0019] Figure 2 It is an analysis report diagram of the ZEMAX system in the embodiment of the present utility model.

[0020] Figure 3Schematic diagram of the fiber coupling efficiency of the LED fiber coupling system in the present embodiment of the utility model at wavelengths from 400 nm to 700 nm. Detailed implementation manners

[0021] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0022] In a microscopic system, the utilization rate of the light source is relatively low. The size of the numerical aperture (NA) is restricted by the light collection angle of the system and the fiber material, and it is impossible to ensure the illumination efficiency. By designing and adjusting the parameters of the LED fiber coupling system, the above-mentioned defects can be compensated, thereby realizing the efficient aggregation of the light beam and improving the fiber coupling efficiency. In practical applications, the higher the fiber coupling efficiency, the farther the optical signal can be transmitted, the smaller the signal loss, and ultimately the luminous efficiency of the microscopic system can be improved.

[0023] Figure 1 The structural schematic diagram of the LED fiber coupling system with a high NA value according to the present utility model is shown. As Figure 1 shown, the present utility model provides a high-NA LED fiber coupling system, which includes a first lens, a second lens, and a third lens that are sequentially arranged on the light-emitting path of the lamp bead 1 and are coaxially arranged. Among them, the first lens is an aspherical plano-convex lens L1, the second lens is an aspherical plano-convex lens L2, and the third lens is a plano-convex lens L3. The three lenses collect the light beam emitted by the lamp bead 1 to the maximum extent, minimize the loss of light, and ensure that the light beam with high-efficiency coupling enters the optical fiber 2.

[0024] More specifically, the focal length of the first lens (aspherical plano-convex lens L1) is f1, the focal length of the second lens (aspherical plano-convex lens L2) is f2, and the focal length of the third lens (plano-convex lens L3) is f3, and f1 < f2 < f3 is satisfied.

[0025] In the present utility model, the detailed parameters of the LED fiber coupling system are shown in Table 1:

[0026]

[0027]

[0028] Table 1

[0029] In Table 1, surface numbers 0 to 7 are the object plane (lamp bead 1), the front end surface of the aspheric plano-convex lens L1, the rear end surface of the aspheric plano-convex lens L1, the front end surface of the aspheric plano-convex lens L2, the rear end surface of the aspheric plano-convex lens L2, the front end surface of the plano-convex lens L3, the rear end surface of the plano-convex lens L3, and the image plane (optical fiber 2). The thickness of surface number 1 is 14 mm to 15 mm, which means that the thickness from surface number 1 to surface number 1 to surface number 2 is 14 mm to 15 mm, that is, the thickness from the front end surface of the aspheric plano-convex lens L1 to the rear end surface of the aspheric plano-convex lens L1 is 14 mm to 15 mm. The material of surface number 0 is air, which means that the material from surface number 0 to surface number 1 is air, and the thickness and material of other surfaces are similar.

[0030] Based on the above parameters, simulation calculation is performed by ZEMAX software. Figure 2 The ZEMAX system analysis report diagram in the embodiment of the utility model is shown as follows: Figure 2 As shown, the object space NA value of the LED fiber coupling system is 0.866, that is, the light receiving angle of the system can reach 120°. It can be seen that the LED fiber coupling system of the utility model can efficiently aggregate the light beam emitted by the lamp bead, reduce the loss of light, and thus improve its light receiving performance.

[0031] In a specific embodiment, the NA value of the output end of the LED fiber coupling system is 0.516. Figure 3 The schematic diagram of the optical fiber coupling efficiency of the LED optical fiber coupling system in the embodiment of the utility model at a wavelength of 400nm to 700nm is shown, as shown in FIG. Figure 3 As shown, when using an optical fiber with an NA value of 0.52 for transmission, the optical fiber coupling efficiency is calculated, and the optical fiber coupling efficiency of each wavelength in the spectral range of 400nm to 700nm can be as high as 100%. It can be seen that the LED optical fiber coupling system described in the utility model fully utilizes the light beam emitted by the lamp bead 1, and has excellent optical effects.

[0032] In summary, the LED fiber coupling system described in the utility model compensates for the limitation of low illumination efficiency in the microscope system by designing and adjusting system parameters, thereby achieving efficient aggregation of light beams and ultimately improving the fiber coupling efficiency and the luminous efficiency of the microscope system.

[0033] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "upper", "lower", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The simple fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to improve. Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. A high-NA LED fiber optic coupling system, characterized in that, It includes a first lens, a second lens and a third lens; the first lens is an aspherical plano-convex lens L1, the second lens is an aspherical plano-convex lens L2, and the third lens is a plano-convex lens L3; the focal length of the first lens is f1, the focal length of the second lens is f2, and the focal length of the third lens is f3, where f1 < f2 < f3.

2. The LED optical fiber coupling system according to claim 1, wherein The thickness from the front end face to the rear end face of L1 is 14 mm to 15 mm, the thickness from the front end face to the rear end face of L2 is 25 mm to 28 mm, and the thickness from the front end face to the rear end face of L3 is 15 mm to 18 mm.

3. The LED optical fiber coupling system according to claim 1, characterized in that The curvature radius of the light-emitting surface of the aspherical plano-convex lens L1 facing away from the lamp bead is -10 mm to -12 mm.

4. The LED optical fiber coupling system according to claim 1, wherein The curvature radius of the light-emitting surface of the aspherical plano-convex lens L2 facing away from the lamp bead is -18 mm to -20 mm.

5. The LED optical fiber coupling system according to claim 1, wherein The curvature radius of the light-collecting surface of the plano-convex lens L3 facing the lamp bead is 24 mm to 26 mm.

6. The LED optical fiber coupling system according to claim 1, wherein, The materials of the first lens and the second lens are B270 glass.

7. The LED optical fiber coupling system according to claim 1, wherein The material of the third lens is H-K9L glass.

8. The LED optical fiber coupling system according to claim 1, characterized in that, The first lens, the second lens and the third lens are coaxially arranged in sequence along the direction of the light beam emitted by the lamp bead.

9. The LED optical fiber coupling system according to claim 1, wherein The system is arranged between the object surface and the image surface, the object surface is the surface of the lamp bead, and the image surface is the surface of the optical fiber.

10. The LED optical fiber coupling system according to claim 1, characterized in that, The numerical aperture NA of the optical fiber is greater than or equal to 0.516.

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