Optical imaging lens group, scanning display device and application

Abstract

The utility model discloses an optical imaging lens group, a scanning display device and application, and relates to the technical field of scanning display. The optical imaging lens group provided by the utility model comprises a plurality of spherical lenses which are sequentially arranged along the same optical axis from the second side to the first side, the aberration in the imaging process can be greatly reduced, and in addition, the full-spherical optical imaging lens group adopting the projection objective lens structure meets the requirements of large view field, small distortion and high resolution, and also considers small size and light weight.

Description

Technical Field

[0001] The present application relates to the field of scanning display technology, and in particular to an optical imaging lens assembly, a scanning display device and applications. Background Art

[0002] Scanning display imaging, as an emerging display technology, can be used in a variety of application scenarios such as projection display and near-eye display.

[0003] However, existing scanning display imaging systems usually use eyepiece-type vehicle-mounted projection lenses for imaging. Due to the structural characteristics of eyepiece-type vehicle-mounted projection lenses, it is difficult to balance aberrations such as coma and astigmatism in the imaging process under a large field of view, resulting in the eyepiece-type vehicle-mounted projection lens being difficult to take into account both a large field of view and high-quality imaging characteristics. Utility Model Content

[0004] The purpose of the present application is to provide an optical imaging lens group and a scanning display device to meet the needs of vehicle-mounted projection scenarios, which can greatly reduce the aberration in the imaging process and meet the requirements of large field of view, small distortion and high resolution.

[0005] Another object of the present application is to provide an application of a scanning display device, which is configured for use in the field of vehicle-mounted projection and has the characteristics of high imaging quality, miniaturization, and light weight.

[0006] The present application provides an optical imaging lens group, which at least includes a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, a seventh lens, and an eighth lens, which are arranged in sequence along the second side to the first side on a common optical axis, wherein the second side corresponds to a curved surface image at a light source end, and the curved surface image is formed by configuring an optical fiber scanner; wherein the object side surfaces of the first lens, the second lens, the fifth lens, and the eighth lens are all concave surfaces, and the concave surfaces are bent toward the curved surface image, the image side surfaces of the first lens, the second lens, and the fifth lens are all convex surfaces, the image side surface of the eighth lens is all convex or concave, the third lens is a biconvex lens, the fourth lens is a biconcave lens, the object side surfaces of the sixth lens and the seventh lens are both convex surfaces, the image side surface of the sixth lens is a convex surface, and the image side surface of the seventh lens is a concave surface.

[0007] Furthermore, in a preferred embodiment of the present application, the optical powers corresponding to the first lens to the eighth lens are respectively positive or negative, positive, positive, negative, positive or negative, positive, positive, negative.

[0008] Furthermore, in a preferred embodiment of the present application, the ratio of the focal length of the first lens to the total focal length of the optical imaging lens assembly is in the range of -33.03 to 20.11.

[0009] Furthermore, in a preferred embodiment of the present application, the ratio of the focal length of the fifth lens to the total focal length of the optical imaging lens assembly is in the range of -2.49 to 142.79.

[0010] Furthermore, in a preferred embodiment of the present application, the third lens and the fourth lens are combined to form a cemented lens and form a common intermediate surface.

[0011] Furthermore, in a preferred embodiment of the present application, the optical imaging lens group also includes a ninth lens, the ninth lens is located between the second lens and the third lens, the object side surface of the ninth lens is a convex surface, and the image side surface of the ninth lens is a concave surface.

[0012] Furthermore, in a preferred embodiment of the present application, the optical imaging lens assembly further includes a tenth lens, the tenth lens is located between the fourth lens and the fifth lens, the object side surface of the tenth lens is a concave surface, and the image side surface of the tenth lens is a convex surface.

[0013] The present application also provides a scanning display device, which includes a fiber scanner and the aforementioned optical imaging lens group, wherein the fiber scanner is used to scan and emit light of an image to be displayed, and the optical imaging lens group is used to magnify, image and project a scanning surface corresponding to the light emitted by the fiber scanner; wherein the fiber scanner includes an actuator and an optical fiber fixed to the actuator, and the portion of the optical fiber that exceeds the actuator forms a fiber cantilever, and the fiber cantilever performs two-dimensional scanning under the drive of the actuator.

[0014] The present application also provides an application of the scanning display device as described above, which includes: configuring the scanning display device in the field of vehicle-mounted display.

[0015] The following technical effects can be achieved by using the technical solution in the embodiments of the present application:

[0016] (1) The full-spherical optical imaging lens group with a projection objective structure can greatly reduce the aberration in the imaging process, meeting the requirements of large field of view, small distortion, and high resolution while taking into account small size and light weight;

[0017] (2) The full-spherical lens design takes into account the advantages of low cost and rapid verification;

[0018] (3) By placing the aperture between the lenses, the diameter of each lens can be designed to be smaller, thereby ensuring that the overall volume of the optical imaging lens group is made smaller;

[0019] (4) By configuring the above-mentioned optical imaging lens group in a fiber scanner, a miniaturized and lightweight scanning display device is formed, and the scanning display device is configured and applied in the field of vehicle-mounted projection, which can meet the requirements of large viewing angle, high resolution and low distortion of vehicle-mounted projection.

[0020] Other features and advantages of the present application will be described in the subsequent description, and partly become apparent from the description, or understood by implementing the technical solution of the present application. The purpose and other advantages of the present application can be realized and obtained through the structures and / or processes specifically pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0022] Figure 1a , 1b is a schematic diagram of the structure of an illustrative scanning display system;

[0023] Figure 2 is a schematic diagram of the scanning output of the optical fiber scanner provided in an embodiment of the present application;

[0024] Figure 3 is a schematic structural diagram of an optical imaging lens assembly provided in Example 1 of the present application;

[0025] Figure 4 is an aberration distribution diagram of an optical imaging lens assembly provided in Example 1 of the present application;

[0026] Figure 5 is an MTF curve diagram of the optical imaging lens assembly in Example 1 of the present application;

[0027] Figure 6 is a field curvature distortion curve diagram of the optical imaging lens assembly in the first embodiment of the present application;

[0028] Figure 7 is a vertical axis chromatic aberration diagram of the optical imaging lens assembly in Example 1 of the present application;

[0029] Figure 8 is a structural schematic diagram of an optical imaging lens assembly provided in Example 2 of the present application;

[0030] Fig. 9 is an aberration distribution diagram of an optical imaging lens assembly provided in Example 2 of the present application;

[0031] Fig.10 is an MTF curve diagram of the optical imaging lens assembly in the second embodiment of the present application;

[0032] Fig.11is a field curvature distortion curve diagram of the optical imaging lens assembly in the second embodiment of the present application;

[0033] Fig.12 is a vertical axis chromatic aberration diagram of the optical imaging lens assembly in Example 2 of the present application;

[0034] Fig.13 is a schematic structural diagram of an optical imaging lens assembly provided in Embodiment 3 of the present application;

[0035] Fig.14 is an aberration distribution diagram of an optical imaging lens assembly provided in Example 3 of the present application;

[0036] Fig.15 is an MTF curve diagram of the optical imaging lens assembly in the third embodiment of the present application;

[0037] Fig.16 is a field curvature distortion curve diagram of the optical imaging lens assembly in the third embodiment of the present application;

[0038] Fig.17 is a vertical axis chromatic aberration diagram of the optical imaging lens assembly in Example 3 of the present application;

[0039] Fig.18 is a schematic structural diagram of an optical imaging lens assembly provided in Embodiment 4 of the present application;

[0040] Fig.19 is an aberration distribution diagram of an optical imaging lens assembly provided in Example 4 of the present application;

[0041] Fig. 20 MTF curve diagram of the optical imaging lens assembly in the fourth embodiment of the present application;

[0042] Fig.21 is a field curvature distortion curve diagram of the optical imaging lens assembly in the fourth embodiment of the present application;

[0043] Fig. 22 This is a vertical axis chromatic aberration diagram of the optical imaging lens assembly in the fourth embodiment of the present application.

[0044] Icons: 100-processor; 110-laser group; 120-fiber scanning module; 130-transmission fiber; 140-light source modulation circuit; 150-scanning drive circuit; 160-beam combining unit; 121-scanning actuator; 121a-slow axis; 121b-fast axis; 122-fiber cantilever; 123-mirror group; 124-scanner packaging shell; 125-fixing part; 230-scanning surface; 240-imaging plane. DETAILED DESCRIPTION

[0045] The present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the related application, rather than to limit the application. It is also necessary to explain that, for ease of description, only the parts related to the related application are shown in the accompanying drawings.

[0046] Illustrative Scanning Display System

[0047] For current scanning display imaging, it can be realized by a digital micromirror device (DMD) or a fiber scanning display (FSD) device. Among them, the FSD solution is a new scanning display imaging method, which realizes the scanning output of the image through a fiber scanner. In order to enable those skilled in the art to clearly understand the present application scheme, the brief principle of fiber scanning imaging and the corresponding system are described below.

[0048] like Figure 1a As shown, it is an illustrative scanning display system in this application, which mainly includes:

[0049] The processor 100 , the laser group 110 , the optical fiber scanning module 120 , the transmission optical fiber 130 , the light source modulation circuit 140 , the scanning driving circuit 150 and the beam combining unit 160 .

[0050] The processor 100 may be a graphics processing unit (GPU), a central processing unit (CPU), or other chips or circuits with control functions and image processing functions, which are not specifically limited here.

[0051] When the system is working, the processor 100 can control the light source modulation circuit 140 to modulate the laser group 110 according to the image data to be displayed. The laser group 110 includes multiple monochromatic lasers, which emit light beams of different colors. As can be seen from FIG1 , the laser group can specifically use three-color lasers: red (Red, R), green (Green, G), and blue (Blue, B). The light beams emitted by the lasers in the laser group 110 are combined into a laser beam by the beam combining unit 160 and coupled into the transmission optical fiber 130.

[0052] The processor 100 may also control the scanning driving circuit 150 to drive the optical fiber scanner in the optical fiber scanning module 120 to scan, thereby scanning and outputting the light beam transmitted in the transmission optical fiber 130 .

[0053] The light beam output by the optical fiber scanner acts on a certain pixel position on the surface of the medium, and forms a light spot at the pixel position, thereby realizing the scanning of the pixel position. Driven by the optical fiber scanner, the output end of the transmission optical fiber 130 sweeps along a certain scanning trajectory, so that the light beam moves to the corresponding pixel position. In the actual scanning process, the light beam output by the transmission optical fiber 130 will form a light spot with corresponding image information (such as color, grayscale or brightness) at each pixel position. In one frame of time, the light beam traverses each pixel position at a sufficiently high speed to complete the scanning of one frame of image. Due to the characteristic of "visual residual" when the human eye observes things, the human eye cannot perceive the movement of the light beam at each pixel position, but sees a complete frame of image.

[0054] Continue to refer Figure 1b , is a specific structure of the optical fiber scanning module 120, which includes: a scanning actuator 121, an optical fiber cantilever 122, a mirror assembly 123, a scanner package 124 and a fixing member 125. The scanning actuator 121 is fixed in the scanner package 124 by the fixing member 125. The transmission optical fiber 130 extends from the front end of the scanning actuator 121 to form an optical fiber cantilever 122 (also called a scanning optical fiber). When working, the scanning actuator 121 is driven by a scanning driving signal, and its slow axis 121a (also called a first actuating portion) moves along a vertical direction (the vertical direction is parallel to Figure 1a , 1b The Y-axis in the reference coordinate system (in this application, the vertical direction may also be referred to as the first direction) vibrates, and its fast axis 121b (also referred to as the second actuating portion) vibrates along the horizontal direction (the horizontal direction is parallel to Figure 1a , 1b The optical fiber cantilever 122 is driven by the scanning actuator 121 to perform two-dimensional scanning according to a preset trajectory and emit a light beam, and the emitted light beam can be scanned and imaged through the lens group 123. Generally, the structure formed by the scanning actuator 121 and the optical fiber cantilever 122 can be called an optical fiber scanner.

[0055] like Figure 2 As shown, in the embodiment of the present application, the movement trajectory of the light-emitting end of the optical fiber forms a scanning surface 230 through the movement of the fast and slow axes, and is converted into an imaging plane 240 after passing through the corresponding lens group 123 (when imaging on a planar carrier, the image is a plane. It should be noted that in other embodiments of the present application, the image formed after passing through the lens group 123 can correspond to the surface of the imaging carrier, that is, it can change with the shape of the carrier surface, as long as the image is clear).

[0056] In order to facilitate description and enable those skilled in the art to easily understand the solution of the present application, it should be noted that the optical imaging lens assembly (such as Figure 2 The lens group 123 shown in the figure is used as an eyepiece. Through the action of the optical imaging lens group, the scanning surface 230 can be converted into an imaging plane 240 (in actual application, the transmission direction of the light is: from the scanning surface 230 to the imaging plane 240).

[0057] It should be further explained that, in the field of projection, the image corresponding to the imaging end is a plane image, and the corresponding plane image carrier can be a projection screen, a curtain, a ground, a glass surface or a wall, etc. The image corresponding to the light source end is a curved surface image, that is, an arc-shaped scanning surface scanned by a fiber optic scanner or emitted by other image sources; in the usage scenario of the camera field, the optical path is opposite to that in the projection field. The light source end generally corresponds to the object side for collecting image information, and the imaging end generally corresponds to the image side obtained by collecting imaging.

[0058] Optical imaging lens

[0059] Please refer to Figure 3 , Figure 8 , Fig.13 as well as Fig.18The optical imaging lens group in the embodiment of the present application at least includes a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, a seventh lens, and an eighth lens which are arranged in sequence along the second side to the first side on a common optical axis, wherein the second side corresponds to a curved surface image at the light source end, and the curved surface image is formed by the configuration of the optical fiber scanner; wherein the object side surfaces of the first lens, the second lens, the fifth lens, and the eighth lens are all concave surfaces, and the concave surfaces are curved toward the curved surface image, the image side surfaces of the first lens, the second lens, and the fifth lens are all convex surfaces, the image side surface of the eighth lens is convex or concave, the third lens is a biconvex lens, the fourth lens is a biconcave lens, the object side surfaces of the sixth lens and the seventh lens are all convex surfaces, the image side surface of the sixth lens is convex, and the image side surface of the seventh lens is concave. In the embodiment of the present specification, the object side surface is the side of the lens facing the curved surface image, and the image side surface is the side of the lens away from the curved surface image. Specifically, the surface of the second side of the optical imaging lens group is a concave surface, that is, the surface of the first lens opposite to the curved surface image is a concave surface, and the concave surface of the second side and the curved surface image are oriented in the same direction, so that the lens closest to the curved surface image can be well adapted to the curved surface image, which is conducive to receiving light with a large viewing angle, so that information from the curved surface image can be more fully and comprehensively captured. In addition, the object image surface of the first lens and the second lens are both concave surfaces facing the curved surface image, and the combination of the two can play an effect similar to that of a Qiming lens, which will not cause large spherical aberration, coma and astigmatism while introducing field curvature. Further, the fifth lens in the optical imaging lens group adopts a double concave lens, which can correct the field curvature and coma in the optical imaging process. The surfaces opposite to the sixth lens and the seventh lens are both convex surfaces, and the sixth lens and the seventh lens are both lenses with positive optical power, which can suppress the central light and the edge light entering the sixth lens and the seventh lens, so that the fifth lens and the fourth lens will not produce too much optical power contribution when the edge light is low, thereby controlling the total focal length of the optical imaging lens group to reach the expected focal length range. Furthermore, the eighth lens is a lens with a negative focal length, and its image side surface can be convex or concave, which can avoid introducing large spherical aberration while correcting distortion, further ensuring the imaging quality. Furthermore, by setting the aperture between the lenses, the diameter of each lens in the optical imaging lens group can be made smaller, thereby realizing the miniaturization and lightness of the overall structure of the optical imaging lens group.

[0060] The optical imaging lens assembly provided in this embodiment of the present application meets the requirements of large field of view, small distortion, and high resolution while taking into account small size and light weight. In addition, the full-spherical lens design takes into account the advantages of low cost and rapid verification.

[0061] Furthermore, the lens surfaces on both sides of the aperture (for example, the image side surface of the fourth lens and the object side surface of the fifth lens in Embodiments 1, 2, and 3; for another example, the image side surface of the fourth lens and the object side surface of the tenth lens in Embodiment 4) are all concave surfaces, which can introduce a larger field curvature to the final imaging surface during the optical imaging process, reduce the distortion of the final imaging surface of the optical imaging lens assembly, and thus improve the imaging quality of the optical imaging lens assembly.

[0062] Furthermore, the optical powers corresponding to the first lens to the eighth lens are respectively positive or negative, positive, positive, negative, positive or negative, positive, positive, negative. In the embodiment of the present application, by reasonably optimizing the positive and negative focal lengths of the multiple co-axial lenses of the optical imaging lens group, the optical power of the system can be reasonably dispersed, the aberrations generated by the lenses can be mitigated, the purpose of correcting various aberrations can be achieved, and clear imaging of the image side curved surface can be achieved. It should be noted that, in the present application, the optical axis direction extending from the second side to the first side is the positive direction, and the optical axis direction extending from the first side to the second side is the negative direction.

[0063] Furthermore, the ratio of the focal length of the first lens to the total focal length of the imaging lens group is in the range of -33.03 to 20.11. The first lens adopts a meniscus lens with a large focal length, which can avoid introducing too large spherical aberration and coma while correcting field curvature, and avoid introducing too large spherical aberration while correcting distortion.

[0064] Furthermore, the third lens and the fourth lens are combined to form a cemented lens and form a common intermediate plane, wherein the fourth lens with negative optical power is closer to the first side relative to the third lens with positive optical power. The cemented lens is used here mainly to balance the system coma and astigmatism of the optical imaging lens group. In addition, after the light emitted by the curved image is diverged and converged by multiple lenses, the cemented lens formed by the third lens and the fourth lens diverges the converged light, which can ensure that the light converges in the same plane, while eliminating spherical aberration and chromatic aberration in the imaging process, ensuring the imaging quality.

[0065] Furthermore, the ratio of the focal length of the fifth lens to the total focal length of the optical imaging lens assembly is in the range of -2.49 to 142.79. Here, the fifth lens adopts a meniscus lens with a large focal length, which can avoid introducing too large spherical aberration and coma while correcting field curvature, and avoid introducing too large spherical aberration while correcting distortion.

[0066] Furthermore, the optical imaging lens assembly further includes a ninth lens, which is located between the second lens and the third lens, the object side surface of the ninth lens is a convex surface, and the image side surface of the ninth lens is a concave surface. In the optical imaging lens assembly provided in the embodiment of the present specification, by arranging the ninth lens between the second lens and the third lens, the aberration generated by the adjacent lenses during the imaging process can be shared, and at the same time, part of the optical power can be shared.

[0067] Furthermore, the optical imaging lens group also includes a tenth lens, the tenth lens is located between the fourth lens and the fifth lens, the object side surface of the tenth lens is a concave surface, and the image side surface of the tenth lens is a convex surface. The image side surface of the fourth lens and the object side surface of the tenth lens are both concave surfaces, which can introduce a large field curvature to the final imaging image surface during the optical imaging process, reduce the distortion of the final imaging image surface of the optical imaging lens group, and thus improve the imaging quality of the optical imaging lens group. In addition, the tenth lens can share the aberrations generated during the imaging process, so that the curvature of the fifth lens can be designed to be smaller, which is convenient for the processing of the fifth lens and reduces the production difficulty and cost.

[0068] Furthermore, in a possible implementation manner, the multiple lenses may be connected in an interval manner or bonded together in an adhesive manner, which will be determined according to the needs of the actual application and is not limited here.

[0069] Further optionally, in a possible implementation, multiple lenses are made of plastic or glass. It should be noted that lenses made of plastic can effectively reduce production costs. Compared with glass materials, the cost of plastic lenses is one twentieth to one tenth of the cost of glass, so it is very conducive to low-cost mass production; in addition, plastic lenses can usually be injection molded, which has low processing difficulty and can be easily processed into various surface structures that meet aspheric surfaces. At the same time, plastic materials can also reduce the weight of the lens as a whole, which is conducive to its lightweight product design. When using glass materials, the refractive index of glass materials is higher and wider, and it has advantages in correcting lens aberrations; the expansion coefficient of glass materials is much smaller, which is conducive to precision assembly. In addition, due to the characteristics of glass itself such as high temperature resistance, UV resistance, and acid and alkali resistance, the service life and performance stability of the lens group have strong advantages. Of course, it should be emphasized that in other embodiments of the present application, it is not limited to the two materials of plastic and glass provided in the embodiments of the present application, and it can also be other materials that can make lenses.

[0070] Embodiment 1

[0071] Figure 3A schematic diagram of the structure of an optical imaging lens group provided in Example 1. The optical imaging lens group includes eight lenses arranged in sequence along the optical axis, namely, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, an aperture S9, a fifth lens L5, a sixth lens L6, a seventh lens L7 and an eighth lens L8 arranged in sequence from the second side to the first side on the same optical axis, wherein the focal lengths corresponding to the first lens L1 to the eighth lens L8 are positive, positive, positive, negative, positive, positive, positive, positive, negative, respectively. Further, wherein the object side surfaces of the first lens L1, the second lens L2, the fifth lens L5 and the eighth lens L8 are all concave surfaces, and the above-mentioned concave surfaces are curved toward the curved surface image, the image side surfaces of the first lens L1, the second lens L2, the fifth lens L5 and the eighth lens L8 are all convex surfaces, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconcave lens, the object side surfaces of the sixth lens L6 and the seventh lens L7 are all convex surfaces, the image side surface of the sixth lens L6 is a convex surface, and the image side surface of the seventh lens L7 is a concave surface. Further, the third lens L3 and the fourth lens L4 are combined to form a cemented lens and form a common intermediate surface.

[0072] Furthermore, the second side of the optical imaging lens assembly of this embodiment corresponds to the curved image at the light source end, the lens numerical aperture (NA) of the optical imaging lens assembly is 0.27 mm, the total focal length is 1.65 mm, the working distance is 0.45 mm, and the full field angle is 36 degrees. It should be noted that the working distance in the embodiment of this specification refers to the distance between the concave surface of the second side of the optical mirror assembly (i.e., the object side surface of the first lens L1) and the curved image on the optical axis.

[0073] In this embodiment, the relationship between the focal length of each lens and the total focal length of the lens is shown in Table 1:

[0074] Table 1 Parameter table of the relationship between the focal length of each lens and the total focal length of the lens in this embodiment

[0075]

[0076] Furthermore, in the embodiments of this specification, the preferred parameters of the curvature radius, thickness parameter, refractive index and Abbe number of each lens of the optical imaging lens assembly for imaging the curved surface image are shown in Table 2:

[0077] Table 2 Structural parameters of the optical imaging lens assembly in Example 1

[0078]

[0079]

[0080] It should be noted that Table 2 is the detailed structural data of the optical imaging lens assembly of Example 1, wherein the units of the curvature radius, thickness and focal length are all in millimeters, and the order of surfaces S1-16 represents the surfaces from the first side to the second side; the optical surface with a curvature radius of "Infinity" refers to a flat surface.

[0081] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the aberration distribution diagram thereof is as follows: Figure 4 As shown, Figure 4 The abscissa in represents the surface of each lens distributed from the first side to the second side. Figure 4 The vertical axis represents the magnitude of the primary aberration.

[0082] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the optical transfer function curve is as follows: Figure 5 As shown, the field curvature distortion curve is as follows Figure 6 As shown, the vertical axis chromatic aberration curve is as follows Figure 7 As shown; among them, the optical transfer function curve (Modulation Transfer Function, MTF) represents the comprehensive resolution level of an optical system, the field curvature distortion curve represents the F-Tan (theta) distortion value (percentage) under different field angles, and the vertical axis chromatic aberration curve represents the chromatic aberration size perpendicular to the axial direction.

[0083] Depend on Figure 4-Figure 7 It can be observed that the optical imaging lens assembly of Example 1 has good imaging resolution in the full field of view, small optical system distortion, chromatic aberration and aberration, so the optical imaging lens assembly can clearly image the scanned curved surface image of the optical fiber scanner and has good imaging effect.

[0084] In some embodiments, the image side surface S16 of the first lens L1 can also be used as a surface with a reflective function, and the light of the forward optical path passes through all the lenses of the optical imaging lens group and forms a clear magnified real image on the forward projection image plane; the light of the reverse optical path is reflected at the image side surface S16 of the first lens L1, and forms a clear image on the reverse optical path image plane, thereby achieving simultaneous imaging at both ends of the optical axis direction. It should be noted that, in the embodiment of the present application, the image side surface S16 of the first lens L1 is used as a surface with a reflective function, and in other alternative embodiments, the surfaces of other lenses can also be used as surfaces with a reflective function to achieve simultaneous imaging at both ends of the optical axis direction. For example, the surface with a reflective function can be the image side surface S13 of the second lens L2, the object side surface S14 of the second lens L2, the image side surface S11 of the third lens L3, the object side surface S12 of the third lens L3, or the surface of other lenses.

[0085] Of course, in practical applications, the optical imaging lens group may also include a display element, a shell, etc. The display element may be disposed on a first side of the optical imaging lens group, and the optical imaging lens group may be installed in the shell, so that a curved surface image formed by scanning an image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0086] Embodiment 2

[0087] Figure 8 A schematic diagram of the structure of an optical imaging lens group provided in Example 2. The optical imaging lens group includes nine lenses arranged in sequence along the optical axis, namely, a first lens L1, a second lens L2, a ninth lens L9, a third lens L3, a fourth lens L4, an aperture S9, a fifth lens L5, a sixth lens L6, a seventh lens L7 and an eighth lens L8 arranged in sequence from the second side to the first side on the same optical axis, wherein the focal lengths corresponding to the first lens L1 to the ninth lens L9 are negative, positive, positive, negative, negative, positive, negative, negative, positive, negative, positive, respectively. Further, the object side surfaces of the first lens L1, the second lens L2, the fifth lens L5 and the eighth lens L8 are all concave surfaces, and the above-mentioned concave surfaces are curved toward the curved image, the image side surfaces of the first lens L1, the second lens L2, the fifth lens L5 and the eighth lens L8 are all convex surfaces, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconcave lens, the object side surfaces of the sixth lens L6 and the seventh lens L7 are all convex surfaces, the image side surface of the sixth lens L6 is a convex surface, the image side surface of the seventh lens L7 is a concave surface, the object side surface of the ninth lens L9 is a convex surface, and the image side surface of the ninth lens L9 is a concave surface. Further, the third lens L3 and the fourth lens L4 are combined to form a cemented lens, and form a common intermediate surface.

[0088] Furthermore, the second side of the optical imaging lens assembly of this embodiment corresponds to the curved surface image at the light source end, the lens numerical aperture (NA) of the optical imaging lens assembly is 0.29 mm, the total focal length is 1.54 mm, the working distance is 0.38 mm, and the full field of view angle is 40 degrees.

[0089] The relationship parameters between the focal length of each lens and the total focal length of the lens in this embodiment are shown in Table 3:

[0090] Table 3 Parameter table of the relationship between the focal length of each lens and the total focal length of the lens in this embodiment

[0091]

[0092] Furthermore, in the embodiment of the present application, the preferred parameters of the curvature radius, thickness parameter, refractive index and Abbe number of each lens of the optical imaging lens assembly for imaging the curved surface image are shown in Table 4:

[0093] Table 4 Structural parameters of the optical imaging lens assembly in Example 2

[0094]

[0095]

[0096] It should be noted that Table 5 is the detailed structural data of the optical imaging lens assembly of Example 2, wherein the units of the curvature radius, thickness and focal length are all in millimeters, and the order of surfaces S1-18 represents the surfaces from the first side to the second side; the optical surface with a curvature radius of "Infinity" refers to a flat surface.

[0097] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the aberration distribution diagram thereof is as follows: Fig. 9 As shown, Fig. 9 The abscissa in represents the surface of each lens distributed from the first side to the second side. Fig. 9 The vertical axis represents the magnitude of the primary aberration.

[0098] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the optical transfer function curve is as follows: Fig.10 As shown, the field curvature distortion curve is as follows Fig.11 As shown, the vertical axis chromatic aberration curve is as follows Fig.12 As shown; among them, the optical transfer function curve (Modulation Transfer Function, MTF) represents the comprehensive resolution level of an optical system, the field curvature distortion curve represents the F-Tan (theta) distortion value (percentage) under different field angles, and the vertical axis chromatic aberration curve represents the chromatic aberration size perpendicular to the axial direction.

[0099] Depend on Figure 9-12 It can be observed that the optical imaging lens assembly of Example 2 has good imaging resolution in the full field of view, small optical system distortion, chromatic aberration and aberration, so the optical imaging lens assembly can clearly image the scanned curved surface image of the fiber scanner and has good imaging effect.

[0100] In some embodiments, the image side surface S17 of the first lens L1 can be used as a surface with a reflective function, and the light of the forward optical path passes through all the lenses of the optical imaging lens group and forms a clear magnified real image on the forward projection image plane; the light of the reverse optical path is reflected at the image side surface S17 of the first lens L1, and forms a clear image on the reverse optical path image plane, thereby achieving simultaneous imaging at both ends of the optical axis direction. It should be noted that, in the embodiment of the present application, the image side surface S17 of the first lens L1 is used as a surface with a reflective function, and in other alternative embodiments, the surfaces of other lenses can also be used as surfaces with a reflective function to achieve simultaneous imaging at both ends of the optical axis direction. For example, the surface with a reflective function can be the image side surface S15 of the second lens L2, the object side surface S16 of the second lens L2, the image side surface S13 of the ninth lens L9, the object side surface S14 of the ninth lens L9, or the surface of other lenses.

[0101] Of course, in practical applications, the optical imaging lens group may also include a display element, a shell, etc. The display element may be disposed on a first side of the optical imaging lens group, and the optical imaging lens group may be installed in the shell, so that a curved surface image formed by scanning an image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0102] Embodiment 3

[0103] Fig.13 A schematic diagram of the structure of an optical imaging lens group provided in Example 3. The optical imaging lens group includes nine lenses arranged in sequence along the optical axis, namely, a first lens L1, a second lens L2, a ninth lens L9, a third lens L3, a fourth lens L4, an aperture S9, a fifth lens L5, a sixth lens L6, a seventh lens L7 and an eighth lens L8 arranged in sequence along the optical axis from the second side to the first side, wherein the focal lengths corresponding to the first lens L1 to the ninth lens L9 are positive, positive, positive, negative, negative, positive, positive, negative, and positive, respectively. Further, the object side surfaces of the first lens L1, the second lens L2, the fifth lens L5 and the eighth lens L8 are all concave surfaces, and the above-mentioned concave surfaces are curved toward the curved image, the image side surfaces of the first lens L1, the second lens L2 and the fifth lens L5 are all convex surfaces, the image side surface of the eighth lens L8 is a concave surface, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconcave lens, the object side surfaces of the sixth lens L6 and the seventh lens L7 are all convex surfaces, the image side surface of the sixth lens L6 is a convex surface, the image side surface of the seventh lens L7 is a concave surface, the object side surface of the ninth lens L9 is a convex surface, and the image side surface of the ninth lens L9 is a concave surface. Further, the third lens L3 and the fourth lens L4 are combined to form a cemented lens, and form a common intermediate surface.

[0104] Furthermore, the second side of the optical imaging lens assembly of this embodiment corresponds to the curved surface image at the light source end, the lens numerical aperture (NA) of the optical imaging lens assembly is 0.29 mm, the total focal length is 1.55 mm, the working distance is 0.36 mm, and the full field of view angle is 40 degrees.

[0105] In this embodiment, the relationship between the focal length of each lens and the total focal length of the lens is shown in Table 5:

[0106] Table 5 Parameter table of the relationship between the focal length of each lens and the total focal length of the lens in this embodiment

[0107]

[0108] Furthermore, in the embodiment of the present application, the preferred parameters of the curvature radius, thickness parameter, refractive index and Abbe number of each lens of the optical imaging lens assembly for imaging the curved surface image are shown in Table 6:

[0109] Table 6 shows the structural parameters of the optical imaging lens assembly in Example 3

[0110]

[0111] It should be noted that Table 6 shows the detailed structural data of the optical imaging lens assembly of Example 3, wherein the units of the curvature radius, thickness and focal length are all in millimeters, and the order of surfaces S1-18 represents the surfaces from the first side to the second side; the optical surface with a curvature radius of "Infinity" refers to a flat surface.

[0112] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the aberration distribution diagram thereof is as follows: Fig.14 As shown, Fig.14 The abscissa in represents the surface of each lens distributed from the first side to the second side. Fig.14 The vertical axis represents the magnitude of the primary aberration.

[0113] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the optical transfer function curve is as follows: Fig.15 As shown, the field curvature distortion curve is as follows Fig.16 As shown, the vertical axis chromatic aberration curve is as follows Fig.17 As shown; among them, the optical transfer function curve (Modulation Transfer Function, MTF) represents the comprehensive resolution level of an optical system, the field curvature distortion curve represents the F-Tan (theta) distortion value (percentage) under different field angles, and the vertical axis chromatic aberration curve represents the chromatic aberration size perpendicular to the axial direction.

[0114] Depend on Figure 14-17It can be observed that the optical imaging lens assembly of Example 3 has good imaging resolution in the full field of view, small optical system distortion, chromatic aberration and aberration, so the optical imaging lens assembly can clearly image the scanned curved surface image of the fiber scanner and has good imaging effect.

[0115] In some embodiments, the image side surface S17 of the first lens L1 can be used as a surface with a reflective function, and the light of the forward optical path passes through all the lenses of the optical imaging lens group and forms a clear magnified real image on the forward projection image plane; the light of the reverse optical path is reflected at the image side surface S17 of the first lens L1, and forms a clear image on the reverse optical path image plane, thereby achieving simultaneous imaging at both ends of the optical axis direction. It should be noted that, in the embodiment of the present application, the image side surface S17 of the first lens L1 is used as a surface with a reflective function, and in other alternative embodiments, the surfaces of other lenses can also be used as surfaces with a reflective function to achieve simultaneous imaging at both ends of the optical axis direction. For example, the surface with a reflective function can be the image side surface S15 of the second lens L2, the object side surface S16 of the second lens L2, the image side surface S13 of the ninth lens L9, the object side surface S14 of the ninth lens L9, or the surface of other lenses.

[0116] Of course, in practical applications, the optical imaging lens group may also include a display element, a shell, etc. The display element may be disposed on a first side of the optical imaging lens group, and the optical imaging lens group may be installed in the shell, so that a curved surface image formed by scanning an image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0117] Embodiment 4

[0118] Fig.18A schematic diagram of the structure of an optical imaging lens group provided for Example 4. The optical imaging lens group includes ten lenses arranged in sequence along the optical axis, namely, a first lens L1, a second lens L2, a ninth lens L9, a third lens L3, a fourth lens L4, an aperture S9, a tenth lens L10, a fifth lens L5, a sixth lens L6, a seventh lens L7 and an eighth lens L8 arranged in sequence from the second side to the first side on the same optical axis, wherein the focal lengths corresponding to the first lens L1 to the tenth lens L10 are negative, positive, positive, negative, positive, positive, positive, negative, positive, negative, positive, negative, respectively. Further, the object side surfaces of the first lens L1, the second lens L2, the fifth lens L5, the eighth lens L8 and the tenth lens L10 are all concave surfaces, and the above-mentioned concave surfaces are curved toward the curved image, the image side surfaces of the first lens L1, the second lens L2, the fifth lens L5 and the tenth lens L10 are all convex surfaces, the image side surface of the eighth lens L8 is a concave surface, the third lens L3 is a biconvex lens, the fourth lens L4 is a biconcave lens, the object side surfaces of the sixth lens L6 and the seventh lens L7 are all convex surfaces, the image side surface of the sixth lens L6 is a convex surface, the image side surface of the seventh lens L7 is a concave surface, the object side surface of the ninth lens L9 is a convex surface, and the image side surface of the ninth lens L9 is a concave surface. Further, the third lens L3 and the fourth lens L4 are combined to form a cemented lens, and form a common intermediate surface.

[0119] Furthermore, the second side of the optical imaging lens assembly of this embodiment corresponds to the curved surface image at the light source end, the lens numerical aperture (NA) of the optical imaging lens assembly is 0.27 mm, the total focal length is 1.65 mm, the working distance is 0.38 mm, and the full field of view angle is 40 degrees.

[0120] In this embodiment, the relationship between the focal length of each lens and the total focal length of the lens is shown in Table 7:

[0121] Table 7 Parameter table of the relationship between the focal length of each lens and the total focal length of the lens in this embodiment

[0122]

[0123]

[0124] Furthermore, in the embodiment of the present application, the preferred parameters of the curvature radius, thickness parameter, refractive index and Abbe number of each lens of the optical imaging lens assembly for imaging the curved surface image are shown in Table 8:

[0125] Table 8 Structural parameters of the optical imaging lens assembly in Example 4

[0126]

[0127] It should be noted that Table 8 is the detailed structural data of the optical imaging lens assembly of Example 4, wherein the units of the curvature radius, thickness and focal length are all in millimeters, and the order of surfaces S1-S20 represents the surfaces from the first side to the second side; the optical surface with a curvature radius of "Infinity" refers to a flat surface.

[0128] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the aberration distribution diagram thereof is as follows: Fig.19 As shown, Fig.19 The abscissa in represents the surface of each lens distributed from the first side to the second side. Fig.19 The vertical axis represents the magnitude of the primary aberration.

[0129] Furthermore, after testing, when the above optical imaging lens assembly is used to project the image light corresponding to the scanning surface, the optical transfer function curve is as follows: Fig. 20 As shown, the field curvature distortion curve is as follows Fig.21 As shown, the vertical axis chromatic aberration curve is as follows Fig. 22 As shown; among them, the optical transfer function curve (Modulation Transfer Function, MTF) represents the comprehensive resolution level of an optical system, the field curvature distortion curve represents the F-Tan (theta) distortion value (percentage) under different field angles, and the vertical axis chromatic aberration curve represents the chromatic aberration size perpendicular to the axial direction.

[0130] Depend on Figure 19-22 It can be observed that the optical imaging lens assembly of Example 4 has good imaging resolution in the full field of view, small optical system distortion, chromatic aberration and aberration, so the optical imaging lens assembly can clearly image the scanned curved surface image of the optical fiber scanner and has good imaging effect.

[0131] In some embodiments, the image side surface S19 of the first lens L1 can be used as a surface with a reflective function, and the light of the forward optical path passes through all the lenses of the optical imaging lens group and forms a clear magnified real image on the forward projection image plane; the light of the reverse optical path is reflected at the image side surface S19 of the first lens L1, and forms a clear image on the reverse optical path image plane, thereby achieving simultaneous imaging at both ends of the optical axis direction. It should be noted that, in the embodiment of the present application, the image side surface S19 of the first lens L1 is used as a surface with a reflective function, and in other alternative embodiments, the surfaces of other lenses can also be used as surfaces with a reflective function to achieve simultaneous imaging at both ends of the optical axis direction. For example, the surface with a reflective function can be the image side surface S17 of the second lens L2, the object side surface S18 of the second lens L2, the image side surface S15 of the ninth lens L9, the object side surface S16 of the ninth lens L9, or the surface of other lenses.

[0132] Of course, in practical applications, the optical imaging lens group may also include a display element, a shell, etc. The display element may be disposed on a first side of the optical imaging lens group, and the optical imaging lens group may be installed in the shell, so that a curved surface image formed by scanning an image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0133] Scanning display device

[0134] The aforementioned optical imaging lens assembly can be used in conjunction with a fiber scanner (or a corresponding fiber scanning module) to form a scanning display device (such as Figure 1a , 1b As shown, the optical imaging lens group is arranged on the light output path of the optical fiber scanner), wherein the second side of the optical imaging lens group faces the light output direction of the optical fiber scanner. The preferred method is that the optical imaging lens group is coaxial with the central optical axis of the optical fiber scanner. Of course, the structure and general principle of the optical fiber scanner can be referred to the aforementioned Figure 1a , 1b The corresponding content will not be elaborated here.

[0135] In addition, in a possible implementation, the present application also provides an application of the above-mentioned scanning display device, that is, the above-mentioned scanning display device is configured in the projection field, specifically configured and applied in vehicle-mounted projection. It can not only be configured in relevant positions in the vehicle such as on the external body or head-up display, but it can also be configured in the vehicle for projection display, and it can be flexibly set according to the display requirements of the vehicle-mounted projection.

[0136] In some embodiments, the scanning display device can be applied to vehicles, including but not limited to automobiles, motorcycles, electric bicycles, balance vehicles, scooters, etc. In some embodiments, the vehicle-mounted projection system can also be used in other tools with transportation capabilities, such as aircraft, ships, wheelchairs, etc. Taking a car as a specific example, the optical imaging module of the scanning display device can be set at the door, front or rear of the car to project the image onto the ground around the car body. It should be noted that the image corresponding to the imaging end is a plane image, and the corresponding plane image carrier can be, for example, a projection screen, a curtain, the ground or a glass surface. It should be noted that in the specific application of the scanning display device, the number of scanning display devices can be one or more groups. When the scanning display device is located at different positions of the carrier (for example, a vehicle), the specifications of the fiber optic scanner, the distribution of each lens in the optical imaging lens group, the parameters, etc. can be adaptively adjusted according to the specific scene.

[0137] In summary, the spherical optical imaging lens group using a projection objective lens structure in the embodiment of the present application meets the requirements of large field of view, small distortion, and high resolution while taking into account small size and light weight; the spherical lens design takes into account the advantages of low cost and rapid verification; by configuring the above-mentioned optical imaging lens group in a fiber optic scanner, a miniaturized and lightweight scanning display device is formed, and the scanning display device is configured and applied in the field of vehicle-mounted projection, which can meet the requirements of large viewing angle, high resolution, and low distortion of vehicle-mounted projection.

[0138] The above are only preferred specific embodiments of the present application. Each embodiment is only used to illustrate the technical solution of the present application but not to limit the present application. Any technical solution that can be obtained by technical personnel in this field through logical analysis, reasoning or effective experiments based on the concept of the present application should be within the scope of the present application.

[0139] The various embodiments in the present application are described in a progressive manner, and the same or similar parts between the various embodiments can be referenced to each other, and each embodiment focuses on the differences from other embodiments.

[0140] The expressions "first", "second", "the first" or "the second" used in various embodiments of the present disclosure may modify various components regardless of order and / or importance, but these expressions do not limit the corresponding components. The above expressions are only configured for the purpose of distinguishing an element from other elements.

Claims

1. An optical imaging lens assembly, characterized in that: The optical imaging lens group at least comprises a first lens, a second lens, a third lens, a fourth lens, an aperture, a fifth lens, a sixth lens, a seventh lens, and an eighth lens which are sequentially arranged along the second side to the first side on the same optical axis, the second side corresponds to a curved surface image at the light source end, and the curved surface image is formed by the optical fiber scanner; Among them, the object side surfaces of the first lens, the second lens, the fifth lens and the eighth lens are all concave surfaces, and the concave surfaces are curved toward the curved image, the image side surfaces of the first lens, the second lens and the fifth lens are all convex surfaces, the image side surface of the eighth lens is convex or concave, the third lens is a biconvex lens, the fourth lens is a biconcave lens, the object side surfaces of the sixth lens and the seventh lens are all convex surfaces, the image side surface of the sixth lens is convex, and the image side surface of the seventh lens is concave.

2. The optical imaging lens assembly according to claim 1, characterized in that: The optical powers corresponding to the first lens to the eighth lens are respectively positive or negative, positive, positive, negative, positive or negative, positive, positive, negative.

3. The optical imaging lens assembly according to claim 2, characterized in that: The ratio of the focal length of the first lens to the total focal length of the optical imaging lens assembly is in the range of -33.03 to 20.

11.

4. The optical imaging lens assembly according to claim 3, characterized in that: The ratio of the focal length of the fifth lens to the total focal length of the optical imaging lens assembly is in the range of -2.49 to 142.

79.

5. The optical imaging lens assembly according to claim 1, characterized in that: The third lens and the fourth lens are combined to form a cemented lens and form a common intermediate surface.

6. The optical imaging lens assembly according to any one of claims 1 to 5, characterized in that: The optical imaging lens assembly also includes a ninth lens, which is located between the second lens and the third lens. The object side surface of the ninth lens is a convex surface, and the image side surface of the ninth lens is a concave surface.

7. The optical imaging lens assembly according to claim 6, characterized in that: The optical imaging lens group also includes a tenth lens, which is located between the fourth lens and the fifth lens. The object side surface of the tenth lens is a concave surface, and the image side surface of the tenth lens is a convex surface.

8. A scanning display device, characterized in that: A method of manufacturing a fiber optic scanner comprising an optical fiber scanner and an optical imaging lens assembly as described in any one of claims 1 to 7, wherein the optical fiber scanner is used to scan and emit light of an image to be displayed, and the optical imaging lens assembly is used to magnify and project a scanning surface corresponding to the light emitted by the optical fiber scanner; The optical fiber scanner includes an actuator and an optical fiber fixed on the actuator. The portion of the optical fiber that exceeds the actuator forms an optical fiber cantilever. The optical fiber cantilever performs two-dimensional scanning under the drive of the actuator.

9. An application of the scanning display device according to claim 8, characterized in that: The scanning display device is configured in the field of vehicle-mounted display.

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