Collimating optical system and collimating lens
By using a positive power ultralens and micro-nano structure in the collimation optical system, the problems of high cost and insufficient collimation of collimation lenses in the prior art are solved, and high collimation and low cost optical systems are realized.
Patent Information
- Application Number
- CN202421878195.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-05
- Publication Date
- 2025-05-02
- Estimated Expiration
- 2034-08-05
AI Technical Summary
The existing collimating lenses and collimating optical systems have high costs and insufficient collimation due to the use of multi-piece lenses and aspherical lenses.
The superlens is used as the main optical component. The superlens has a positive power and is equipped with a micro-nano structure on the substrate. It is manufactured through a semiconductor process to reduce production costs.
The optical effects of high collimation and small distortion are achieved, while reducing production costs, providing better collimation effects and economical production solutions.
Smart Images
Figure CN222825751U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of optical systems, and in particular to a collimating optical system and a collimating lens. Background Art
[0002] Collimating lenses are commonly used in laser radar, fiber optic communications, laser processing and other fields. Collimating lenses adjust the light beam emitted by the light source into a parallel beam to ensure that the laser beam has a high degree of directionality and a small divergence angle.
[0003] In the prior art, the collimating optical system corresponding to the collimating lens usually uses multiple lenses to improve the collimation degree, and the multiple lenses also include a certain number of aspherical lenses, which leads to the problem of high cost of the collimating optical system and the collimating lens. Utility Model Content
[0004] In view of the above technical problems, the embodiments of the present application provide a collimating optical system and a collimating lens, aiming to provide a collimating optical system and a collimating lens with high collimation and low cost.
[0005] According to one aspect of an embodiment of the present application, a collimating optical system is disclosed, the collimating optical system being used to collimate light emitted by a light source and project the light onto an illuminated object; the collimating optical system comprising: a superlens, the optical focal length of the superlens being positive, the superlens comprising a substrate and a micro-nano structure, at least one of a surface of the substrate close to the light source and a surface of the substrate away from the light source being provided with the micro-nano structure;
[0006] Wherein, the collimating optical system satisfies: Among them, the L 1 is the distance from the light source to the surface of the metalens close to the light source on the optical axis, and f is the effective focal length of the collimating optical system.
[0007] In some embodiments, the collimating optical system satisfies: Among them, the θ 1max is the difference between the phase value of the metalens at the effective semi-aperture and the phase value at the center of the metalens, and the R m1 is the effective semi-aperture of the superlens.
[0008] In some embodiments, the collimating optical system satisfies: Among them, θ 1max / 2 is the difference between the phase value of the metalens at half of the effective semi-aperture and the phase value at the center of the metalens, and the R m1 is the effective semi-aperture of the superlens.
[0009] In some embodiments, the collimating optical system satisfies: Among them, y F1 is the radius of the circumscribed circle of the area enclosed by the light source, θ F1 is the image-side emission angle corresponding to the radius of the circumscribed circle of the area enclosed by the light source itself, and the δ F1 is the divergence half angle of the light source, and the d F1 is the spot radius of the light emitted by the light source on the target surface, and the target surface is the first surface of the superlens provided with the micro-nano structure along the direction from the light source to the illuminated object along the optical axis.
[0010] In some embodiments, the collimating optical system satisfies: Wherein, the TTL is the total optical length of the collimating optical system.
[0011] In some embodiments, the collimating optical system satisfies: Wherein, the TTL is the total optical length of the collimating optical system, and the D out It is the diameter of the light spot of the collimating optical system in the direction from the light source to the illuminated object along the optical axis, at the center field of view of the surface of the last lens away from the light source.
[0012] In some embodiments, the collimating optical system further comprises a spherical lens, which is disposed in the optical path, has a positive optical focal length, and a surface of the spherical lens away from the light source is convex toward the illuminated object.
[0013] In some embodiments, the collimating optical system satisfies: Among them, the f m is the focal length of the superlens, and the f g is the focal length of the spherical lens.
[0014] In some embodiments, the light source includes at least one sub-light source, and the sub-light source is a point light source.
[0015] A second aspect of the embodiments of the present application provides a collimating lens, wherein the collimating lens comprises a collimating optical system as described in any one of the above items.
[0016] The collimating optical system provided in the present application is used to collimate the light emitted by the light source and project it onto the illuminated object; the collimating optical system comprises: a metalens, the optical focal length of the metalens is positive, the metalens comprises a substrate and a micro-nano structure, and at least one of the surface of the substrate close to the light source and the surface of the substrate away from the light source is provided with a micro-nano structure. Among them, the collimating optical system satisfies: Among them, L 1is the distance from the light source to the surface of the metalens close to the light source on the optical axis, and f is the effective focal length of the collimating optical system. The collimating optical system provided by the present application has a high degree of collimation and a small distortion, and a good collimation effect. The collimating optical system includes a metalens, which can be manufactured by semiconductor technology. The cost of a single metalens is low in mass production. Therefore, the collimating optical system provided by the present application has a good collimation effect and a low production cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] The above and other objects, features and advantages of the present application will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings.
[0018] Figure 1 A schematic diagram of the architecture layout of a collimating optical system in an embodiment of the present application is shown.
[0019] Figure 2 A schematic diagram of the light divergence angle of the collimating optical system in one embodiment of the present application is shown.
[0020] Figure 3 A schematic diagram showing the light spot size and position of a collimating optical system in an embodiment of the present application is shown.
[0021] Figure 4 A schematic diagram of the architecture layout of a collimating optical system in an embodiment of the present application is shown.
[0022] Figure 5 A schematic diagram of the light divergence angle of the collimating optical system in one embodiment of the present application is shown.
[0023] Figure 6 A schematic diagram showing the light spot size and position of a collimating optical system in an embodiment of the present application is shown.
[0024] Figure 7 A schematic diagram of the architecture layout of a collimating optical system in an embodiment of the present application is shown.
[0025] Figure 8 A schematic diagram of the light divergence angle of the collimating optical system in one embodiment of the present application is shown.
[0026] Fig. 9 A schematic diagram showing the light spot size and position of a collimating optical system in an embodiment of the present application is shown.
[0027] Fig.10 A schematic diagram of the architecture layout of a collimating optical system in an embodiment of the present application is shown.
[0028] Fig.11 A schematic diagram of the light divergence angle of the collimating optical system in one embodiment of the present application is shown.
[0029] Fig.12 A schematic diagram showing the light spot size and position of a collimating optical system in an embodiment of the present application is shown.
[0030] Fig.13 A schematic diagram of the architecture layout of a collimating optical system in an embodiment of the present application is shown.
[0031] Fig.14 A schematic diagram of the light divergence angle of the collimating optical system in one embodiment of the present application is shown.
[0032] Fig.15 A schematic diagram showing the light spot size and position of a collimating optical system in an embodiment of the present application is shown.
[0033] Reference numerals
[0034] 100. Collimating optical system;
[0035] 10. Super lens; 110. Substrate; 120. Micro-nano structure;
[0036] 20. Spherical lens;
[0037] 30. Aperture;
[0038] 40. Refractive lens;
[0039] A, object plane; B, image plane; S, optical axis. DETAILED DESCRIPTION
[0040] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that the description of the present application will be more comprehensive and complete and the concepts of the example embodiments will be fully conveyed to those skilled in the art. The accompanying drawings are only schematic illustrations of the present application and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and thus their repeated description will be omitted.
[0041] In addition, the described features, structures or characteristics may be combined in one or more example embodiments in any suitable manner. In the following description, many specific details are provided to provide a full understanding of the example embodiments of the present application. However, those skilled in the art will appreciate that the technical solution of the present application may be practiced while omitting one or more of the specific details, or other modules, components, etc. may be adopted. In other cases, known structures, methods, implementations or operations are not shown or described in detail to avoid obscuring the present application and making the various aspects of the present application obscure.
[0042] See also Figure 1 , Figure 1FIG. 1 is a schematic diagram of the structure layout of a collimating optical system 100 in an embodiment of the present application. The collimating optical system 100 is used to collimate the light emitted by the light source and project it onto the illuminated object, wherein the optical axis S is the center line of the light beam emitted by the light source. Figure 1 In the collimating optical system 100, the light source (not shown) is placed on the left side of the collimating optical system 100, and the right side of the light source is the light-emitting side. In this application, the light-emitting surface of the light source is recorded as the object surface A. The illuminated object (not shown) is placed on the right side of the collimating optical system 100, and the surface of the illuminated object is the illuminated surface. In this application, the illuminated surface is recorded as the image surface B. Therefore, in this application, the direction from the light source to the illuminated object along the optical axis S is consistent with the direction from the object surface A to the image surface B along the optical axis S.
[0043] The optical focal length of the metalens 10 is positive. The metalens 10 includes a substrate 110 and a micro-nano structure 120. At least one of the surface of the substrate 110 close to the light source and the surface of the substrate 110 away from the light source is provided with the micro-nano structure 120. The micro-nano structure 120 is a sub-wavelength structure. According to the phase modulation method adopted, the corresponding phase modulation formula can be adaptively used to configure the various parameters of the micro-nano structure 120, so that the metalens 10 has the expected optical performance.
[0044] The collimating optical system 100 satisfies conditional equation 1: Among them, L 1 is the distance from the light source to the surface of the metalens 10 close to the light source on the optical axis S, f is the effective focal length of the collimating optical system 100, L 1 It has the same dimension as f, which is a unit of length, such as millimeters.
[0045] Conditional expression 1 indicates that the metalens 10 is outside the principal plane of the collimating optical system 100 , and the upper and lower limits of conditional expression 1 can ensure that the metalens 10 is in the optimal position.
[0046] The collimating optical system 100 provided in the present application has a high degree of collimation and a small distortion, and has a good collimation effect. The metalens 10 can be manufactured by semiconductor technology, and the cost of a single metalens 10 is low in mass production. Therefore, the collimating optical system 100 provided in the present application has a good collimation effect and a low production cost.
[0047] In some embodiments, the micro-nano structure 120 is disposed on a surface of the substrate 110 close to the light source.
[0048] In some embodiments, the micro-nano structure 120 is disposed on a surface of the substrate 110 facing away from the light source.
[0049] In some embodiments, the surface of the substrate 110 close to the light source and the surface of the substrate 110 away from the light source are both provided with micro-nano structures 120, so that the superlens 10 has a higher degree of design freedom.
[0050] In some embodiments, the micro-nano structure 120 is a positive micro-nano structure.
[0051] In some embodiments, the micro-nano structure 120 is a negative micro-nano structure.
[0052] In some embodiments, the micro-nano structure 120 is provided with a layer to make the processing technology of the superlens 10 compatible with the existing semiconductor processing technology, which can facilitate the processing and manufacturing of the superlens 10.
[0053] In some embodiments, the micro-nano structure 120 has two or more layers, so that the superlens 10 has a larger and expected optical focal length.
[0054] For the superlens 10, the position of the micro-nano structure 120, the positive and negative positions of the micro-nano structure 120, and the number of layers of the micro-nano structure 120 can be freely combined as long as the superlens 10 has the expected performance.
[0055] In some embodiments, the phase distribution of the metalens 10 satisfies the following formula:
[0056]
[0057]
[0058] Wherein, r is the distance from the center of the superlens 10 to any micro-nanostructure 120, λ is the central wavelength of the working band of the superlens 10, is the phase constant, (x, y) is the two-dimensional coordinate of the surface of the metalens 10, a i and b i is a real coefficient, f m is the focal length of the superlens 10.
[0059] Furthermore, in some embodiments, the collimating optical system 100 satisfies Conditional Formula 2: Among them, L 1 is the distance from the light source to the surface of the metalens 10 close to the light source on the optical axis S, f is the effective focal length of the collimating optical system 100, L 1 The dimension of is the same as f, which is a length unit, such as millimeter. Conditional expression 2 more accurately limits the range of the optimal position of the metalens 10.
[0060] In some embodiments, the collimating optical system 100 satisfies Condition 3: Among them, D m1 is the effective semi-aperture of the superlens 10, D m1 The unit is a length unit, such as millimeter. The effective aperture of the metalens 10 refers to the diameter of the circumscribed circle of the maximum light-transmitting area of the metalens 10, and the effective semi-aperture of the metalens 10 is half of the effective aperture of the metalens 10. 1maxis the difference between the phase value of the metalens 10 at the effective semi-aperture and the phase value at the center of the metalens 10. Specifically, θ 1max The difference between the phase value at the effective half-aperture of the superlens 10 and the phase value of the superlens 10 is taken as the origin at the center of the superlens 10, θ 1max The unit is 2πrad.
[0061] Conditional expression 3 limits the metalens 10 to a specific numerical aperture range. Conditional expression 3 can ensure the phase gradient trend of the metalens 10 with a specific numerical aperture within the full aperture, thereby ensuring that the aberration correction effect of the metalens 10 can be maximized.
[0062] In some embodiments, the collimating optical system 100 satisfies Condition 4: Among them, R m1 is the effective semi-aperture of the superlens 10, R m1 The unit of is a length unit, such as millimeters. 1max / 2 is the difference between the phase value of the metalens 10 at half of the effective half-aperture and the phase value at the center of the metalens 10. The definition of the effective half-aperture of the metalens 10 can be referred to above and will not be elaborated here. 1max / 2 The unit is 2πrad.
[0063] Conditional expression 4 limits the metalens 10 to a specific numerical aperture range. Conditional expression 4 can ensure the phase gradient trend of the metalens 10 with a specific numerical aperture within the half aperture, thereby ensuring that the aberration correction effect of the metalens 10 can be maximized.
[0064] In some embodiments, the collimating optical system 100 satisfies Condition 5: Among them, y F1 is the radius of the circumscribed circle of the area enclosed by the light source, y F1 The unit of is a length unit, such as millimeters. F1 is the image-side emission angle corresponding to the radius of the circumscribed circle of the area enclosed by the light source itself, δ F1 is the half angle of divergence of the light source, θ F1 ,δ F1 The unit of d is degree. F1 is the spot radius of the light emitted by the light source on the target surface, and the target surface is the first surface of the metalens 10 provided with the micro-nano structure 120 along the optical axis S from the light source to the illuminated object. Specifically, when the micro-nano structure 120 is provided on the surface of the substrate 110 away from the light source, d F1 is the spot radius of the light emitted by the light source on the surface of the super lens 10 away from the light source; when the micro-nano structure 120 is disposed on the surface of the substrate 110 close to the light source, d F1is the spot radius of the light emitted by the light source on the surface of the superlens 10 close to the light source; when the surface of the substrate 110 facing the light source and the surface of the substrate 110 facing away from the light source are both provided with the micro-nano structure 120, d F1 is the spot radius of the light emitted by the light source on the surface of the super lens 10 close to the light source, d F1 The unit is a length unit, such as millimeters.
[0065] Conditional expression 5 indicates that the superlens 10 is outside the principal plane of the collimating optical system 100 and does not occupy the main optical focal length. The upper and lower limits of conditional expression 5 are used to ensure that the superlens 10 plays a role in correcting aberrations at the optimal position.
[0066] In some embodiments, the collimating optical system 100 satisfies Condition 6: Wherein, f is the effective focal length of the collimating optical system 100, TTL is the total optical length of the collimating optical system 100, and in the present application, the total optical length is the distance from the light source to the surface of the last lens facing away from the light source on the optical axis S along the direction from the light source to the illuminated object; for example, when the last lens of the collimating optical system 100 is a spherical lens 20, TTL is the distance from the light source to the surface of the spherical lens 20 facing away from the light source on the optical axis S. TTL and f have the same dimension, both of which are length units, such as millimeters.
[0067] Conditional expression 6 indicates that the object-side principal plane of the collimating optical system 100 is near the image plane end of the collimating optical system 100 . The upper and lower limits of conditional expression 6 can ensure that the collimating optical system 100 is close to the ideal focal plane imaging, so that the collimating optical system 100 has a better theoretical collimation effect.
[0068] In some embodiments, the collimating optical system 100 satisfies conditional equation 7: Wherein, f is the effective focal length of the collimating optical system 100, TTL is the total optical length of the collimating optical system 100, and D out is the diameter of the light spot of the collimating optical system 100 along the direction from the light source to the illuminated object, at the surface of the last lens away from the light source in the central field of view. For example, if the last lens of the collimating optical system 100 along the direction from the light source to the illuminated object is the metalens 10, then D out is the diameter of the light spot of the surface of the super lens 10 facing away from the light source in the central field of view. f, TTL, D out have the same dimension, which is a unit of length, such as millimeter.
[0069] Conditional Expression 7 indicates that the collimating optical system 100 is an optical system with a small number of lenses, and the collimating optical system 100 has a conventional aperture and a short total optical length.
[0070] In some embodiments, the collimating optical system 100 further includes a spherical lens 20, the optical power of the spherical lens 20 is positive, and the spherical lens 20 is disposed in the optical path. Specifically, the spherical lens 20 can be disposed on the side of the metalens 10 close to the light source; or, the spherical lens 20 is disposed on the side of the metalens 10 away from the light source. When the collimating optical system 100 further includes the spherical lens 20, the collimation degree of the collimating optical system 100 can be further improved, and the distortion of the collimating optical system 100 can be further controlled. Compared with an aspherical lens, the production cost of the spherical lens 20 is lower. Therefore, the collimating optical system 100 provided in this embodiment has a lower production cost while having a better collimation effect.
[0071] In some embodiments, the surface of the spherical lens 20 close to the light source is convex toward the illuminated object.
[0072] In some embodiments, the surface of the spherical lens 20 close to the light source is a plane.
[0073] In some embodiments, the collimating optical system 100 further includes a spherical lens 20, the optical focal length of the spherical lens 20 is positive, and the surface of the spherical lens 20 away from the light source is convex toward the illuminated object. The collimating optical system 100 satisfies conditional formula eight: Among them, f m is the focal length of the superlens 10, f g is the focal length of the spherical lens 20. m and f g have the same dimension, which is a unit of length, such as millimeter.
[0074] Conditional expression 8 indicates that the optical focal length of the metalens 10 is less than that of the spherical lens 20, that is, the metalens 10 does not occupy the main optical focal length in the collimating optical system 100. The upper and lower limits of conditional expression 8 can ensure that the metalens 10 can play a role in correcting aberrations in the collimating optical system 100.
[0075] In some embodiments, the collimating optical system 100 does not include an aperture. Since the light divergence angle and the light center angle of the light source are constant, the light source has determined the field of view parameters of the collimating optical system 100. Therefore, the aperture is not necessary for the collimating optical system 100.
[0076] In some embodiments, the collimating optical system 100 further includes an aperture 30, and the aperture 30 is used to control the amount of light beam passing through and adjust the intensity of the light beam.
[0077] In some embodiments, the aperture 30 is disposed on a side of the superlens 10 close to the light source, specifically:
[0078] (1) The aperture 30 is disposed on the object side of the super lens 10, and the aperture 30 is spaced apart from the super lens 10;
[0079] (2) The aperture 30 is disposed on the surface of the super lens 10 close to the light source, that is, the aperture 30 is disposed in contact with the surface of the super lens 10 close to the light source.
[0080] In some embodiments, the aperture 30 is disposed between the metalens 10 and the spherical lens 20, specifically:
[0081] (1) The aperture 30 is disposed on the surface of the metalens 10 facing away from the light source, that is, the aperture 30 is disposed in contact with the surface of the metalens 10 close to the spherical lens 20;
[0082] (2) The aperture 30 is located between the super lens 10 and the spherical lens 20, and the aperture 30 is spaced apart from the super lens 10 and the spherical lens 20;
[0083] (3) The aperture 30 is disposed on the surface of the spherical lens 20 close to the light source, that is, the aperture 30 is disposed on the surface of the spherical lens 20 close to the light source.
[0084] In some embodiments, the central wavelength of the light source is 940nm±50nm, that is, the collimating optical system 100 provided in the present application can collimate the light emitted by the light source with a central wavelength of 940nm±50nm. Exemplarily, the central wavelength of the light source can be 890nm, 900nm, 910nm, 920nm, 930nm, 940nm, 950nm, 960nm, 970nm, 980nm, 990nm, etc.
[0085] In some embodiments, the light source includes at least one sub-light source, and the sub-light source is a point light source. When the light source includes more than two sub-light sources, the sub-light sources are randomly arranged in an array or regularly arranged in an array.
[0086] In some embodiments, the sub-light source is a VCSEL (Vertical-Cavity Surface-Emitting Laser, VCSEL for short).
[0087] In some embodiments, the sub-light source is an EEL (Edge-Emitting Laser, abbreviated as EEL, edge emitting semiconductor laser).
[0088] The collimating optical system 100 provided in this application has the following benefits:
[0089] (1) The total divergence angle of the light source is ≤25°;
[0090] (2) All emitted light within a 9.2 mm diameter light source has a divergence angle of ≤0.3 mr (milliradians);
[0091] (3) A light source with a diameter of 9.2 mm corresponds to a full light output angle of 20°;
[0092] (4) Total optical length ≤ 31 mm;
[0093] (5) The absolute value of the maximum distortion is ≤0.6%.
[0094] (6) Fewer lenses and lower cost.
[0095] The present application exemplarily provides five collimating optical systems 100 that meet usage requirements in five embodiments. Next, the collimating optical systems 100 provided in the various embodiments of the present application are introduced in detail.
[0096] Example 1
[0097] Figure 1 FIG. 1 shows a schematic diagram of the architecture layout of the collimating optical system 100 provided in Example 1. Figure 1 The collimating optical system 100 includes, in order from the light source to the illuminated object, an aperture 30, a super lens 10, and a spherical lens 20 along the optical axis S. The micro-nano structure 120 is disposed on the surface of the substrate 110 away from the light source, the surface of the spherical lens 20 close to the light source is convex toward the illuminated object, and the surface of the spherical lens 20 away from the light source is convex toward the illuminated object. Some parameters of the collimating optical system 100 provided in Example 1 are shown in Table 1-1.
[0098] Table 1-1. Partial parameters of the collimating optical system 100 provided in Example 1
[0099] parameter data Total optical length (TTL) 30.34mm Light source size φ9.2mm Total divergence angle of light source 20° Effective focal length 26.26mm Working band 940±10nm
[0100] As can be seen from Table 1-1, the total optical length of the collimating optical system 100 is 30.34 mm, and the effective focal length of the collimating optical system 100 is 26.26 mm. In Example 1, the diameter of the light source is 9.2 mm, the full angle of divergence of the light source is 20°, the central wavelength of the light source is 940 nanometers, and the wavelength band of the light emitted by the light source is 930 nanometers to 950 nanometers.
[0101] Along the direction from the light source to the illuminated object along the optical axis S, starting from the light source, each surface in the collimating optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 1-2.
[0102] Table 1-2. Parameters of various surfaces in the collimating optical system 100 provided in Example 1
[0103]
[0104]
[0105] For each surface in Table 1-2, surface 0 is the plane where the light source is located, and surface 1 is the aperture 30. Surface 2 is the surface of the superlens 10 close to the light source, and surface 3 is the surface of the superlens 10 away from the light source. Since the micro-nano structure 120 is provided on the surface of the substrate 110 away from the light source, surface 3 is recorded as the structural surface. Surface 4 is the surface of the spherical lens 20 close to the light source, and surface 5 is the surface of the spherical lens 20 away from the light source.
[0106] As can be seen from Table 1-2, the radius of curvature of surface 0 is infinite, that is, surface 0 is a plane, the distance between surface 0 and surface 1 is 15.22 mm, and the material between surface 0 and surface 1 is air. The radius of curvature of surface 1 is infinite, that is, surface 1 is a plane, and the distance between surface 1 and surface 2 is 0, that is, the aperture 30 is set on the surface of the super lens 10 close to the light source. The distance between surface 2 and surface 3 is 0.85 mm, and the refractive index of the material between surface 2 and surface 3 relative to d light is 1.39-1.57. The radius of curvature of surface 3 is infinite, that is, surface 3 is a plane, the distance between surface 3 and surface 4 is 8.77 mm, and the material between surface 3 and surface 4 is air. Surface 4 is a spherical surface, the radius of curvature of surface 4 is -29.47 mm, the distance between surface 4 and surface 5 is 5.5 mm, and the refractive index of the material between surface 4 and surface 5 relative to d light is 1.93-2.11. The surface 5 is a spherical surface, the curvature radius of the surface 5 is -17.17 mm, the distance between the surface 5 and the illuminated object is not limited, and the material between the surface 5 and the illuminated object is air.
[0107] Figure 2 1 is a schematic diagram of the light divergence angle of the collimating optical system 100 provided in Example 1, wherein the central wavelength of the light source is 940 nanometers. The scale of the light divergence angle diagram is 1mr×1mr, and the figure lists the divergence angles at the scales of 1 / 3, 2 / 3, and 3 / 3 of the light source size. Figure 2 It can be seen that within the full field of view φ9.2mm, the light divergence angle of the optical system is less than 0.75mr, and the RMS (root mean square) radius is less than 0.3mr. Therefore, the collimating optical system 100 provided in Example 1 has the advantages of higher collimation and less distortion.
[0108] Figure 3 When the collimating optical system 100 provided in Example 1 collimates the emitted light of a light source with a central wavelength of 940 nanometers, the light spot size and position on the surface 5 1 meter away from the light source.
[0109] Example 2
[0110] Figure 4 FIG. 1 shows a schematic diagram of the architecture layout of the collimating optical system 100 provided in Example 2. Figure 4The collimating optical system 100 includes, in order from the light source to the illuminated object along the optical axis S, an aperture 30, a spherical lens 20, and a super lens 10, wherein the surface of the spherical lens 20 close to the light source is a plane, and the surface of the spherical lens 20 away from the light source is convex toward the illuminated object; the micro-nano structure 120 is disposed on the surface of the substrate 110 close to the light source. Some parameters of the collimating optical system 100 provided in Example 2 are shown in Table 3-1.
[0111] Table 2-1. Partial parameters of the collimating optical system 100 provided in Example 2
[0112] parameter data Total optical length (TTL) 30.00mm Light source size φ9.2mm Total divergence angle of light source 20° Effective focal length 27.27mm Working band 940±10nm
[0113] As can be seen from Table 2-1, the total optical length of the collimating optical system 100 in Example 2 is 30.00 mm, and the effective focal length of the collimating optical system 100 is 27.27 mm. The diameter of the light source in Example 2 is 9.2 mm, the full angle of divergence of the light source is 20°, the central wavelength of the light source is 940 nanometers, and the wavelength band of the light emitted by the light source is 930 nanometers to 950 nanometers.
[0114] Along the direction from the light source to the illuminated object along the optical axis S, starting from the light source, each surface in the collimating optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 3-2.
[0115] Table 2-2. Parameters of various surfaces in the collimating optical system 100 provided in Example 2
[0116] Surface serial number Surface type Curvature radius (mm) Thickness(mm) d Refractive index 0 Spherical unlimited 23.00 - 1 Aperture unlimited 0 - 2 Spherical unlimited 5 1.64～1.82 3 Spherical -30.5 1.23 - 4 Structural surface unlimited 0.77 1.37～1.55 5 Spherical unlimited - -
[0117] For each surface in Table 2-2, surface 0 is the plane where the light source is located, and surface 1 is the aperture 30. Surface 2 is the surface of the spherical lens 20 close to the light source, and surface 3 is the surface of the spherical lens 20 away from the light source. Surface 4 is the surface of the superlens 10 close to the light source. Since the micro-nano structure 120 is provided on the surface of the substrate 110 away from the light source, surface 4 is recorded as the structural surface. Surface 5 is the surface of the superlens 10 away from the light source.
[0118] The analysis of each surface in Table 2-2 can refer to Example 1 and will not be analyzed here.
[0119] Figure 5 Schematic diagram of the light divergence angle of the collimating optical system 100 provided in Example 2, wherein the central wavelength of the light source is 940 nanometers. The scale of the light divergence angle diagram is 10mr×10mr, and the figure lists the divergence angles at the scales of 1 / 3, 2 / 3, and 3 / 3 of the light source size. Figure 5It can be seen that within the full field of view φ9.2mm, the light divergence angle of the optical system is less than 3.3mr, and the RMS (root mean square) radius is less than 2.3mr. Therefore, the collimation optical system 100 provided in Example 2 has good collimation.
[0120] Figure 6 When the collimating optical system 100 provided in Example 2 collimates the emitted light of a light source with a central wavelength of 940 nanometers, the light spot size and position on the surface 5 1 meter away from the light source.
[0121] Example 3
[0122] Figure 7 FIG. 1 shows a schematic diagram of the architecture layout of the collimating optical system 100 provided in Example 3. Figure 7 The collimating optical system 100 includes, in order from the light source to the illuminated object along the optical axis S, an aperture 30 and a super lens 10, wherein the micro-nano structure 120 is disposed on the surface of the substrate 110 close to the light source. Some parameters of the collimating optical system 100 provided in Example 3 are shown in Table 4-1.
[0123] Table 3-1. Partial parameters of the collimating optical system 100 provided in Example 3
[0124] parameter data Total optical length (TTL) 27.25mm Light source size φ9.2mm Total divergence angle of light source 20° Effective focal length 26.76mm Working band 940±10nm
[0125] As can be seen from Table 3-1, the total optical length of the collimating optical system 100 is 27.25 mm, and the effective focal length of the collimating optical system 100 is 26.76 mm. In Example 3, the diameter of the light source is 9.2 mm, the full angle of divergence of the light source is 20°, the central wavelength of the light source is 940 nanometers, and the wavelength band of the light emitted by the light source is 930 nanometers to 950 nanometers.
[0126] Along the direction from the light source to the illuminated object along the optical axis S, starting from the light source, each surface in the collimating optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 4-2.
[0127] Table 3-2. Parameters of various surfaces in the collimating optical system 100 provided in Example 3
[0128] Surface serial number Surface type Curvature radius (mm) Thickness(mm) d Refractive index 0 Spherical unlimited 26.48 - 1 Aperture unlimited 0 - 2 Structural surface unlimited 0.77 1.37～1.55 3 Spherical unlimited - -
[0129] For each surface in Table 3-2, surface 0 is the plane where the light source is located, and surface 1 is the aperture 30. Surface 2 is the surface of the superlens 10 close to the light source. Since the micro-nano structure 120 is provided on the surface of the substrate 110 close to the light source, surface 2 is recorded as the structural surface. Surface 3 is the surface of the superlens 10 away from the light source.
[0130] The analysis of each surface in Table 3-2 can refer to Example 1 and will not be further analyzed here.
[0131] Figure 8 Schematic diagram of the light divergence angle of the collimating optical system 100 provided in Example 3, wherein the central wavelength of the light source is 940 nanometers. The scale of the light divergence angle diagram is 10mr×10mr, and the figure lists the divergence angles at the scales of 1 / 3, 2 / 3, and 3 / 3 of the light source size. Figure 8 It can be seen that within the full field of view φ9.2 mm, the light divergence angle of the optical system is less than 4 mr, and the RMS (root mean square) radius is less than 1.7 mr. Therefore, the collimation optical system 100 provided in Example 3 has good collimation.
[0132] Fig. 9 When the collimating optical system 100 provided in Example 3 collimates the emitted light of a light source with a central wavelength of 940 nanometers, the light spot size and position on the surface 3 1 meter away from the light source.
[0133] Example 4
[0134] Fig.10 FIG. 4 shows a schematic diagram of the architecture layout of the collimating optical system 100 provided in Example 4. Fig.10 The collimating optical system 100 includes, in order from the light source to the illuminated object along the optical axis S, an aperture 30 and a super lens 10, wherein the micro-nano structure 120 is disposed on the surface of the substrate 110 close to the light source. Some parameters of the collimating optical system 100 provided in Example 4 are shown in Table 5-1.
[0135] Table 4-1. Partial parameters of the collimating optical system 100 provided in Example 4
[0136] parameter data Total optical length (TTL) 27.26mm Light source size φ9.2mm Total divergence angle of light source 20° Effective focal length 26.76mm Working band 940±2nm
[0137] As shown in Table 4-1, the total optical length of the collimating optical system 100 is 27.26 mm, and the effective focal length of the collimating optical system 100 is 26.76 mm. In Example 4, the diameter of the light source is 9.2 mm, the divergence angle of the light source is 20°, the central wavelength of the light source is 940 nanometers, and the wavelength band of the light emitted by the light source is 938 nanometers to 942 nanometers.
[0138] Along the direction from the light source to the illuminated object along the optical axis S, starting from the light source, each surface in the collimating optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 4-2.
[0139] Table 4-2. Parameters of various surfaces in the collimating optical system 100 provided in Example 4
[0140]
[0141]
[0142] For each surface in Table 4-2, surface 0 is the plane where the light source is located, and surface 1 is the aperture 30. Surface 2 is the surface of the superlens 10 close to the light source. Since the micro-nano structure 120 is provided on the surface of the substrate 110 close to the light source, surface 2 is recorded as the structural surface. Surface 3 is the surface of the superlens 10 away from the light source.
[0143] The analysis of each surface in Table 4-2 can refer to Example 1 and will not be further analyzed here.
[0144] Fig.11 Schematic diagram of the light divergence angle of the collimating optical system 100 provided in Example 4, wherein the central wavelength of the light source is 940 nanometers. The scale of the light divergence angle diagram is 4mr×4mr, and the figure lists the divergence angles at the scales of 1 / 3, 2 / 3, and 3 / 3 of the light source size. Fig.11 It can be seen that within the full field of view φ9.2mm, the light divergence angle of the optical system is less than 1.4mr, and the RMS (root mean square) radius is less than 0.6mr. Therefore, the collimation optical system 100 provided in Example 4 has good collimation.
[0145] Fig.12 When the collimating optical system 100 provided in Example 4 collimates the emitted light of a light source with a central wavelength of 940 nanometers, the light spot size and position on the surface 3 1 meter away from the light source.
[0146] Example 5
[0147] Fig.13 FIG. 1 shows a schematic diagram of the architecture layout of the collimating optical system 100 provided in Example 5. Fig.13 The collimating optical system 100 includes, in order from the light source to the illuminated object, an aperture 30, a super lens 10, and a spherical lens 20 along the optical axis S, wherein the micro-nano structure 120 is disposed on the surface of the substrate 110 away from the light source; the surface of the spherical lens 20 close to the light source is convex toward the illuminated object, and the surface of the spherical lens 20 away from the light source is convex toward the illuminated object. Some parameters of the collimating optical system 100 provided in Example 5 are shown in Table 5-1.
[0148] Table 5-1. Partial parameters of the collimating optical system 100 provided in Example 5
[0149] parameter data Total optical length (TTL) 30.28mm Light source size φ9.2mm Total divergence angle of light source 24° Effective focal length 26.25mm Working band 940±10nm
[0150] As shown in Table 5-1, the total optical length of the collimating optical system 100 is 30.28 mm, and the effective focal length of the collimating optical system 100 is 26.25 mm. In Example 1, the diameter of the light source is 9.2 mm, the full angle of divergence of the light source is 24°, the central wavelength of the light source is 940 nm, and the wavelength band of the light emitted by the light source is 930 nm to 950 nm.
[0151] Along the direction from the light source to the illuminated object along the optical axis S, starting from the light source, each surface in the collimating optical system 100 is numbered, and the parameters of each surface are summarized to obtain the following Table 5-2.
[0152] Table 5-2. Parameters of various surfaces in the collimating optical system 100 provided in Example 5
[0153] Surface serial number Surface type Curvature radius (mm) Thickness(mm) d Refractive index 0 Spherical unlimited 15.02 - 1 Aperture unlimited 0 - 2 Spherical unlimited 0.85 1.39～1.57 3 Structural surface unlimited 8.91 - 4 Spherical -30.33 5.5 1.93～2.11 5 Spherical -17.31 - -
[0154] The analysis of each surface in Table 5-2 can refer to Example 1 and will not be further analyzed here.
[0155] Fig.14 Schematic diagram of the light divergence angle of the collimating optical system 100 provided in Example 5, wherein the central wavelength of the light source is 940 nanometers. The scale of the light divergence angle diagram is 4mr×4mr, and the figure lists the divergence angles at the scales of 1 / 3, 2 / 3, and 3 / 3 of the light source size. Fig.14 It can be seen that within the full field of view φ9.2mm, the light divergence angle of the optical system is less than 1.1mr, and the RMS (root mean square) radius is less than 0.4mr. Therefore, the collimating optical system 100 provided in Example 5 has the advantages of high collimation and small distortion.
[0156] Fig.15 When the collimating optical system 100 provided in Example 5 collimates the emitted light of a light source with a central wavelength of 940 nanometers, the light spot size and position on the surface 5 1 meter away from the light source.
[0157] After summarizing the various parameters of the collimating optical system 100 provided in the above five embodiments, the following Table 6 is obtained. Table 6 is mainly used to illustrate that the various conditions satisfied by the collimating optical system 100 provided in each embodiment of the present application are all verified and supported by experiments.
[0158] Table 6. Parameters of the collimating optical system 100 provided in various embodiments
[0159]
[0160]
[0161] The present application also provides a collimating lens, which includes the collimating optical system 100. The structure and layout of the collimating optical system 100 can be referred to above and will not be described here. The collimating lens provided in the present application includes but is not limited to a lens used as a laser radar transmitting end.
[0162] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the utility model disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the appended claims.
Claims
1. A collimating optical system, characterized in that: The collimating optical system is used to collimate the light emitted by the light source and project it onto the illuminated object; the collimating optical system comprises: a super lens, the optical focal length of the super lens is positive, the super lens comprises a substrate and a micro-nano structure, and at least one of a surface of the substrate close to the light source and a surface of the substrate away from the light source is provided with the micro-nano structure; Wherein, the collimating optical system satisfies: Wherein, L1 is the distance from the light source to the surface of the superlens close to the light source on the optical axis, and f is the effective focal length of the collimating optical system.
2. The collimating optical system according to claim 1, characterized in that: The collimating optical system satisfies: Among them, the θ 1max is the difference between the phase value of the metalens at the effective semi-aperture and the phase value at the center of the metalens, and the R m1 is the effective semi-aperture of the superlens.
3. The collimating optical system according to claim 1, characterized in that: The collimating optical system satisfies: Among them, θ 1max / 2 is the difference between the phase value of the metalens at half of the effective semi-aperture and the phase value at the center of the metalens, and the R m1 is the effective semi-aperture of the superlens.
4. The collimating optical system according to claim 1, characterized in that: The collimating optical system satisfies: Among them, y F1 is the radius of the circumscribed circle of the area enclosed by the light source, θ F1 is the image-side emission angle corresponding to the radius of the circumscribed circle of the area enclosed by the light source itself, and the δ F1 is the divergence half angle of the light source, and the d F1 is the spot radius of the light emitted by the light source on the target surface, and the target surface is the first surface of the superlens provided with the micro-nano structure along the direction from the light source to the illuminated object along the optical axis.
5. The collimating optical system according to claim 1, characterized in that: The collimating optical system satisfies: Wherein, the TTL is the total optical length of the collimating optical system.
6. The collimating optical system according to claim 1, characterized in that: The collimating optical system satisfies: Wherein, the TTL is the total optical length of the collimating optical system, and the D out It is the diameter of the light spot of the collimating optical system in the direction from the light source to the illuminated object along the optical axis, at the center field of view of the surface of the last lens away from the light source.
7. The collimating optical system according to any one of claims 1 to 6, characterized in that: The collimating optical system further comprises a spherical lens, which is arranged in the optical path, has a positive optical focal length, and a surface of the spherical lens away from the light source is convex toward the illuminated object.
8. The collimating optical system according to claim 7, characterized in that: The collimating optical system satisfies: Among them, the f m is the focal length of the superlens, and the f g is the focal length of the spherical lens.
9. The collimating optical system according to any one of claims 1 to 6, characterized in that: The light source includes at least one sub-light source, and the sub-light source is a point light source.
10. A collimating lens, characterized in that: Comprising the collimating optical system as described in any one of claims 1-9.