Optical imaging lens, scanning display device and near-eye display device

Abstract

The embodiment of the application discloses an optical imaging lens, a scanning display device and a near-eye display device, and relates to the technical field of scanning display. The optical imaging lens can reasonably disperse the optical power of the system, slow down the aberration generated by the lens, achieve the purpose of correcting various aberrations, and realize clear imaging of the image surface on the basis of improving the field of view by reasonably optimizing the focal lengths of five coaxial lenses of the optical imaging lens. The field of view and the imaging quality are further improved by limiting and optimizing the refractive index, the dispersion coefficient and the surface structure of the five coaxial lenses. The overall structure of the optical imaging lens can be more compact on the basis of further improving the imaging quality by limiting and optimizing the five coaxial lenses to be aspherical surface structures, so that the production demand of miniaturization of the lens product is met.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of scanning display, in particular to an optical imaging lens, a scanning display device and a near-eye display device. BACKGROUND

[0002] Scanning display imaging as a new display technology can be used in various application scenarios such as projection display and near-eye display.

[0003] However, in the existing scanning display imaging system, there are high processing difficulty, high mass production cost, poor imaging quality, small field of view angle and the inability to be miniaturized, which limits the application of scanning display imaging technology in the market, especially when it is applied to the near-eye display scenario. The imaging effect and the field of view angle affect the performance requirements of high resolution in the near-eye display, thereby hindering the development of the near-eye display to the consumer market. SUMMARY

[0004] The purpose of the present application is to provide an optical imaging lens, a scanning display device and a near-eye display device to meet the requirements of large field of view angle, high imaging quality, easy processing and low cost in the near-eye display scenario.

[0005] The present application provides an optical imaging lens, which comprises at least a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence from a first side to a second side and sharing an optical axis, wherein the focal lengths of the first lens to the fifth lens are negative, positive, positive, negative and positive respectively.

[0006] Optionally, the various lenses satisfy the following relationship: -0.6≤f4 / f≤-0.3 and 0.44≤f5 / f≤0.65, wherein f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, and f is the focal length of the optical imaging lens.

[0007] The second side surface of the fifth lens is concave near the optical axis.

[0008] Optionally, the various lenses satisfy the following relationship: -2.3≤f1 / f≤-0.7, 0.41≤f2 / f≤12.1 and 0.38≤f3 / f≤0.99, wherein f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, and f is the focal length of the optical imaging lens.

[0009] The various lenses satisfy the following relationship: 1.53≤n1≤1.72, 1.49≤n2≤1.68, 1.49≤n3≤1.57, 1.69≤n4≤1.76, 1.62≤n5≤1.68; wherein n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, n3 is the refractive index of the third lens, n4 is the refractive index of the fourth lens, and n5 is the refractive index of the fifth lens.

[0010] The dispersion coefficients of the various lenses satisfy: 30.8≤v1≤47.3, 31.4≤v2≤70.2, 63.6≤v3≤70.4, 27.6≤v4≤30.8, 51.5≤v5≤60.3; wherein v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, v3 is the Abbe number of the third lens, v4 is the Abbe number of the fourth lens, and v5 is the Abbe number of the fifth lens.

[0011] Optionally, n1 is 1.53 or 1.55 or 1.69 or 1.72, n2 is 1.49 or 1.61 or 1.68, n3 is 1.49 or 1.55 or 1.56 or 1.57, n4 is 1.69 or 1.73 or 1.75 or 1.76, and n5 is 1.62 or 1.68.

[0012] The dispersion coefficients of the various lenses satisfy: the Abbe number of the first lens is 30.8 or 31.8 or 47.3 or 52.8, the Abbe number of the second lens is 31.4 or 34.5 or 60.7 or 70.2, the Abbe number of the third lens is 63.6 or 64.7 or 70.4, the Abbe number of the fourth lens is 27.6 or 29.5 or 30.8, and the Abbe number of the fifth lens is 51.5 or 60.3.

[0013] Optionally, the first side surface of the fifth lens is convex, the first side surface of the fourth lens is concave, and the second side surface of the fourth lens is convex or concave.

[0014] Optionally, the first side surface of the third lens is concave or convex, and the second side surface of the third lens is convex.

[0015] Optionally, the first side surface of the first lens is convex, and the second side surface of the first lens is concave at the near optical axis; the first side surface of the second lens is convex, and the second side surface of the second lens is convex or concave.

[0016] The first side surface and the second side surface of the first lens to the fifth lens are aspherical surface structures.

[0017] The second side of the optical imaging lens group corresponds to a curved surface image, and the first side of the optical imaging lens group corresponds to a planar image.

[0018] This application embodiment also provides a scanning display device, which includes a fiber optic scanner and the aforementioned optical imaging lens group. The fiber optic scanner is used to scan and emit light of an image to be displayed, and the optical imaging lens group is used to magnify and project the scanning surface corresponding to the light emitted by the fiber optic scanner.

[0019] The fiber optic scanner includes an actuator and an optical fiber fixed to the actuator. The portion of the optical fiber extending beyond the actuator forms an optical fiber cantilever, which performs two-dimensional scanning under the drive of the actuator.

[0020] This application embodiment also provides a near-eye display device, which is used as a head-mounted augmented reality device, and includes at least a near-eye display module and a scanning display device according to the above description, wherein the scanning display device is disposed in the near-eye display module.

[0021] This application embodiment also provides a near-eye display device, which is used as a head-mounted virtual reality device and includes at least a near-eye display module and a scanning display device according to the above description, wherein the scanning display device is disposed in the near-eye display module.

[0022] The technical solutions adopted in the embodiments of this application can achieve the following technical effects:

[0023] In this embodiment, by reasonably optimizing the focal length of the five coaxial 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 reduced, and the purpose of correcting various aberrations can be achieved. Thus, clear imaging of the image surface can be achieved while improving the field of view. At the same time, the overall structure of the optical imaging lens group is made more compact by configuring a reasonable number of lenses, which meets the production needs of miniaturized lens products.

[0024] Furthermore, by optimizing the refractive index, dispersion coefficient, and surface structure of the five coaxial lenses, the field of view and imaging quality were further improved.

[0025] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the technical solutions of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures and / or processes particularly pointed out in the description, claims and drawings. Attached Figure Description

[0026] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0027] Figure 1a , 1b This is an illustrative structural diagram of a scanning display system;

[0028] Figure 2a This is a schematic diagram of the scanning output of the fiber optic scanner provided in an embodiment of this application;

[0029] Figure 2b This is a schematic diagram showing the positional relationship between the optical imaging lens group, the entrance pupil position, the exit pupil position, and the corresponding exit pupil distance provided in the embodiments of this application;

[0030] Figure 3 This is a schematic diagram of the structure of an optical imaging lens assembly provided in Embodiment 1 of this application;

[0031] Figure 4 This is the MTF curve of the optical imaging lens group in Embodiment 1 of this application;

[0032] Figure 5 This is a field curvature distortion curve of the optical imaging lens group in Embodiment 1 of this application;

[0033] Figure 6 This is the chromatic aberration diagram of the optical imaging lens group in Embodiment 1 of this application.

[0034] Figure 7 This is a schematic diagram of the structure of an optical imaging lens assembly provided in Embodiment 2 of this application;

[0035] Figure 8 This is the MTF curve of the optical imaging lens group in Embodiment 2 of this application;

[0036] Figure 9 This is a field curvature distortion curve of the optical imaging lens group in Embodiment 2 of this application;

[0037] Figure 10 This is the transverse chromatic aberration diagram of the optical imaging lens group in Embodiment 2 of this application;

[0038] Figure 11 This is a schematic diagram of the structure of an optical imaging lens assembly provided in Embodiment 3 of this application;

[0039] Figure 12 This is the MTF curve of the optical imaging lens group in Embodiment 3 of this application;

[0040] Figure 13 This is a field curvature distortion curve of the optical imaging lens group in Embodiment 3 of this application;

[0041] Figure 14This is the transverse chromatic aberration diagram of the optical imaging lens group in Embodiment 3 of this application;

[0042] Figure 15 This is a schematic diagram of the structure of an optical imaging lens assembly provided in Embodiment 4 of this application;

[0043] Figure 16 This is the MTF curve of the optical imaging lens group in Embodiment 4 of this application;

[0044] Figure 17 This is a field curvature distortion curve of the optical imaging lens group in Embodiment 4 of this application;

[0045] Figure 18 This is the transverse chromatic aberration diagram of the optical imaging lens group in Embodiment 4 of this application;

[0046] Figure 19 This is a schematic diagram of the structure of an optical imaging lens assembly provided in Embodiment 5 of this application;

[0047] Figure 20 This is the MTF curve of the optical imaging lens group in Embodiment 5 of this application;

[0048] Figure 21 This is a field curvature distortion curve of the optical imaging lens group in Embodiment 5 of this application;

[0049] Figure 22 This is the chromatic aberration diagram of the optical imaging lens group in Embodiment 5 of this application.

[0050] Icons: 100-Processor; 110-Laser Group; 120-Fiber Optic 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 Optic Cantilever; 123-Mirror Group; 124-Scanner Package; 125-Fixture; 230-Scanning Surface; 240-Imaging Plane; 11-First Lens; 12-Second Lens; 13-Third Lens; 14-Fourth Lens; 15-Fifth Lens; 16-Sixth Lens; 01-Aperture; 02-Scanning Surface; 31-First Lens; 32 - Second lens; 33- Third lens; 34- Fourth lens; 35- Fifth lens; 36- Sixth lens; 03- Aperture stop; 04- Scanning surface; 51- First lens; 52- Second lens; 53- Third lens; 54- Fourth lens; 55- Fifth lens; 05- Aperture stop; 06- Scanning surface; 71- First lens; 72- Second lens; 73- Third lens; 74- Fourth lens; 75- Fifth lens; 76- Sixth lens; 07- Aperture stop; 08- Scanning surface; 91- First lens; 92- Second lens; 93- Third lens; 94- Fourth lens; 95- Fifth lens; 09- Aperture stop; 10- Scanning surface. Detailed Implementation

[0051] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0052] Illustrative scanning display system

[0053] Current scanning display imaging can be achieved using either a Digital Micromirror Device (DMD) or a Fiber Scanning Display (FSD) device. The FSD approach, as a novel scanning display imaging method, uses a fiber optic scanner to achieve image scanning output. To enable those skilled in the art to clearly understand the present application, a brief explanation of the principles and corresponding system of fiber optic scanning imaging is provided below.

[0054] like Figure 1a The image shown is an illustrative scanning display system according to this application, which mainly includes:

[0055] The system includes a processor 100, a laser assembly 110, a fiber optic scanning module 120, a transmission fiber optic cable 130, a light source modulation circuit 140, a scanning drive circuit 150, and a beam combining unit 160.

[0056] The processor 100 can be a graphics processing unit (GPU), a central processing unit (CPU), or other chips or circuits with control and image processing functions, without being specifically limited here.

[0057] When the system is in operation, the processor 100 controls the light source modulation circuit 140 to modulate the laser group 110 according to the image data to be displayed. The laser group 110 contains multiple monochromatic lasers, each emitting a beam of a different color. As shown in Figure 1, the laser group can specifically use red (R), green (G), and blue (B) lasers. The beams emitted by each laser in the laser group 110 are combined into a single laser beam by the beam combining unit 160 and coupled into the transmission optical fiber 130.

[0058] The processor 100 can also control the scanning drive circuit 150 to drive the fiber scanner in the fiber scanning module 120 to perform scanning, thereby scanning and outputting the beam transmitted in the transmission fiber 130.

[0059] A beam of light output from a fiber optic scanner acts on a specific pixel on the surface of a medium, forming a light spot at that pixel, thus achieving scanning of that pixel location. Driven by the fiber optic scanner, the output end of the transmission fiber 130 sweeps along a specific scanning trajectory, causing the beam to move to the corresponding pixel location. During the actual scanning process, the beam output from the transmission fiber 130 forms a light spot with corresponding image information (such as color, grayscale, or brightness) at each pixel location. Within one frame, the beam traverses each pixel location at a sufficiently high speed to complete the scanning of one frame of the image. Due to the "visual persistence" characteristic of human vision, the human eye cannot perceive the movement of the beam at each pixel location, but instead sees a complete image frame.

[0060] Continue to refer to Figure 1b The specific structure of the fiber optic scanning module 120 includes: a scanning actuator 121, a fiber optic cantilever 122, a mirror assembly 123, a scanner housing 124, and a fixing member 125. The scanning actuator 121 is fixed to the scanner housing 124 by the fixing member 125. The transmission fiber 130 extends from the front end of the scanning actuator 121 to form the fiber optic cantilever 122 (also called the scanning fiber). During operation, driven by the scanning drive signal, the slow axis 121a (also called the first actuation part) of the scanning actuator 121 moves along the vertical direction (this vertical direction is parallel to the...). Figure 1a , 1b The Y-axis in the reference coordinate system (in this application, the vertical direction can also be referred to as the first direction) vibrates, and its fast axis 121b (also referred to as the second actuator) vibrates along the horizontal direction (this horizontal direction is parallel to the reference coordinate system). Figure 1a , 1b The X-axis in the reference coordinate system (in this application, this horizontal direction can also be referred to as the second direction) vibrates, driven by the scanning actuator 121. The front end of the fiber optic cantilever 122 performs a two-dimensional sweep along a preset trajectory and emits a light beam. The emitted light beam can then pass through the mirror assembly 123 to achieve scanning imaging. Generally, the structure composed of the scanning actuator 121 and the fiber optic cantilever 122 can be called a fiber optic scanner.

[0061] like Figure 2a As shown in this embodiment, the motion trajectory of the optical fiber output end forms a scanning surface 230 through the movement of the fast and slow axes. After passing through the corresponding lens group 123, it is converted into an imaging plane 240. When applied to near-eye display devices such as augmented reality (AR) devices, the imaging plane 240 is coupled into the waveguide as the entrance pupil of the waveguide to form an image for human viewing.

[0062] To facilitate description and enable those skilled in the art to easily understand the solution of this application, it should be noted that the optical imaging lens assembly in this application (such as...) Figure 2aThe lens group 123 shown serves as an eyepiece. Through the action of this optical imaging lens group, the scanning surface 230 can be converted into an imaging plane 240 (in practical applications, the direction of light transmission is from the scanning surface 230 to the imaging plane 240). Therefore, the side of the optical imaging lens group corresponding to the imaging plane 240 is referred to as the first side, and the side of the optical imaging lens group corresponding to the scanning surface 230 is referred to as the second side. In the following description, "first side" and "second side" will be used as references to describe the embodiment of the optical imaging lens group. Furthermore, in the description of the subsequent embodiments, such as for a certain lens in the optical imaging lens group, "the first side surface of the Xth lens" refers to the surface of the Xth lens facing the first side.

[0063] It should be further noted that in the field of projection, the image corresponding to the first side is a planar image, and the corresponding planar image carrier can be such as a projection screen, a screen, or a wall. The image corresponding to the second side is a curved image, that is, an arc-shaped scanning surface scanned by a fiber optic scanner or emitted by other image sources. In the application scenario of the camera field, the optical path is reversed in the field of projection. The first side generally corresponds to the object side that collects image information, and the second side generally corresponds to the image side that is captured and formed.

[0064] Optical imaging lens

[0065] The optical imaging lens assembly in this embodiment includes at least five lenses: a first lens, a second lens, a third lens, a fourth lens, and a fifth lens, arranged coaxially from the first side to the second side. It should be noted that the focal lengths of the first to fifth lenses in this embodiment are negative, positive, positive, negative, and positive, respectively. Furthermore, by simultaneously optimizing the positive and negative values ​​of the focal lengths of the five coaxial lenses, the optical power of the system can be reasonably dispersed, aberrations generated by the lenses can be reduced, and the purpose of correcting various aberrations can be achieved. This results in clear imaging of the image plane while increasing the field of view.

[0066] More specifically, preferably, the various lenses satisfy the following relationships: -2.3≤f1 / f≤-0.7, 0.41≤f2 / f≤12.1, 0.38≤f3 / f≤0.99, -0.6≤f4 / f≤-0.3, and 0.44≤f5 / f≤0.65; where f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, and f is the focal length of the optical imaging lens group (which can also be understood as the equivalent focal length of the optical imaging lens group). It should be noted that by more specifically defining the focal length of each lens, the optical power of the system is more rationally distributed and configured, thereby further strengthening the correction of various aberrations and improving the field of view and imaging quality. Additionally, if the location of the lens focal length is not defined in this embodiment, it means that the focal length of the lens can be the focal length of the lens near the optical axis. It is important to emphasize that prior to this invention, existing optical imaging lens assemblies for projection displays could not achieve a balance between image quality and a large field of view. Typically, increasing the field of view would reduce image quality, while maintaining image quality would limit the range of possible field of view. The invention of this application, however, achieves high-quality image output while simultaneously increasing the field of view and miniaturizing the image through combined control of the focal length and surface structure of the five lenses.

[0067] Furthermore, in one possible implementation, the five lenses can be connected by spacing or by adhesive bonding, depending on the needs of the actual application, and no limitation is imposed here.

[0068] Furthermore, in one possible implementation, the various lenses described above also satisfy the following relationship:

[0069] The refractive indices are defined as follows: 1.53≤n1≤1.72, 1.49≤n2≤1.68, 1.49≤n3≤1.57, 1.69≤n4≤1.76, 1.62≤n5≤1.68; where n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, n3 is the refractive index of the third lens, n4 is the refractive index of the fourth lens, and n5 is the refractive index of the fifth lens. Preferably, n1 is 1.53, 1.55, 1.69, or 1.72; n2 is 1.49, 1.61, or 1.68; n3 is 1.49, 1.55, 1.56, or 1.57; n4 is 1.69, 1.73, 1.75, or 1.76; and n5 is 1.62 or 1.68. It should be noted that by optimizing the refractive index of the five lenses, the dispersion coefficient of the corresponding lenses can be reasonably controlled to ensure image quality and a large field of view.

[0070] Further optionally, in order to better ensure imaging quality, the embodiments of the present invention specifically and preferably limit the dispersion coefficients of the five lenses, wherein the dispersion coefficients of the various lenses satisfy: 30.8≤v1≤47.3, 31.4≤v2≤70.2, 63.6≤v3≤70.4, 27.6≤v4≤30.8, 51.5≤v5≤60.3; wherein v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, v3 is the Abbe number of the third lens, v4 is the Abbe number of the fourth lens, and v5 is the Abbe number of the fifth lens. Specifically, the preferred configurations are as follows: the Abbe number of the first lens is 30.8, 31.8, 47.3, or 52.8; the Abbe number of the second lens is 31.4, 34.5, 60.7, or 70.2; the Abbe number of the third lens is 63.6, 64.7, or 70.4; the Abbe number of the fourth lens is 27.6, 29.5, or 30.8; and the Abbe number of the fifth lens is 51.5 or 60.3. It should be noted that in other embodiments of the present invention, the Abbe numbers are not limited to the five lenses specified in the embodiments of the present invention; other dispersion coefficients that can ensure a good matching relationship among the five lenses can also be used, thereby ensuring the final image quality.

[0071] Further optionally, in one possible implementation, the first side surface of the first lens is convex, and the second side surface of the first lens is concave near the optical axis; the first side surface of the second lens is convex, and the second side surface of the second lens is either convex or concave; the first side surface of the third lens is either concave or convex, and the second side surface of the third lens is convex; the first side surface of the fourth lens is concave, and the second side surface of the fourth lens is either convex or concave; the first side surface of the fifth lens is convex, and the second side surface of the fifth lens is concave near the optical axis. It should be noted that by defining the surface shape structure of the corresponding side surfaces of the lenses, aberrations generated between lenses can be further effectively corrected, optical sensitivity reduced, and the final image quality and field of view improved. It should also be noted that, as mentioned herein, a convex surface means that the first side surface forms a raised shape towards the first side of the optical imaging lens group; a concave surface means that the first side surface forms a recessed shape towards the first side of the optical imaging lens group; a convex surface means that the second side surface forms a raised shape towards the second side of the optical imaging lens group; a concave surface means that the second side surface forms a recessed shape towards the second side of the optical imaging lens group. It should be emphasized that, in other embodiments of the present invention, the limitation is not limited to simultaneously defining the surface structure of all lenses as in this embodiment; it is also possible to limit only the surface structure of at least one lens, such as limiting only the surface structure of the first and second side surfaces of the fifth lens, without limiting the surface structure of other lenses.

[0072] Furthermore, in some embodiments, the lens surface is not entirely concave or convex; the lens surface may be a composite curved surface, or the near-optical axis portion may be curved while the edge portion is not curved. In particular, optionally, when the lens surface is convex and the position of the convex surface is not defined, it means that the convex surface can be located near the optical axis of the lens surface. Similarly, when the lens surface is concave and the position of the concave surface is not defined, it means that the concave surface can be located near the optical axis of the lens surface.

[0073] Further optionally, in one possible implementation, the first and second side surfaces of the first to fifth lenses are both aspherical surface structures. It should be noted that by designing the mirror structure of the first to fifth lenses as an aspherical surface structure, more control variables can be obtained to reduce aberrations and reasonably reduce the number of lenses. Therefore, while improving image display quality, it also contributes to the miniaturization or micro-miniaturization of optical imaging lens groups. Furthermore, the fact that the first and second side surfaces of the aforementioned lenses are both aspherical surface structures can be understood as meaning that the entire or a portion of the optically effective area of ​​the lens surface is aspherical.

[0074] Alternatively, in one possible implementation, the first to fifth lenses are all made of plastic or glass. It should be noted that using plastic for the first to fifth lenses can effectively reduce production costs. Compared to glass, the cost of plastic lenses is one-twentieth to one-tenth of that of glass lenses, thus greatly benefiting low-cost mass production. Furthermore, plastic lenses are typically injection molded, which is easy to process and can be readily fabricated into various aspherical surface structures. Plastic also reduces the overall weight of the lens, facilitating lightweight product design. When using glass, its higher and wider refractive index offers advantages in correcting lens aberrations. Glass also has a much lower coefficient of thermal expansion, which is beneficial for precision assembly. Additionally, glass's inherent resistance to high temperatures, ultraviolet radiation, and acids and alkalis gives the lens assembly a strong advantage in terms of lifespan and performance stability. It should be emphasized that other embodiments of the present invention are not limited to the plastic and glass materials provided in the embodiments of the present invention; other materials suitable for making lenses can also be used.

[0075] Additionally, it should be noted that the optical imaging lens assembly disclosed in the embodiments of the present invention may optionally include at least one aperture stop, which may be located before the first lens (on the first side), between the lenses, or after the last fifth lens (on the second side). The aperture stop may be of the type such as an aperture stop or a field stop, which can be used to reduce stray light and help improve the image display quality.

[0076] Furthermore, in some embodiments, the optical imaging lens group in this application also satisfies the following optical characteristics:

[0077] In the optical imaging lens group, multiple lenses are arranged coaxially from the entrance pupil to the exit pupil. The exit pupil corresponds to the curved image, i.e., the second side of the optical imaging lens group; the entrance pupil corresponds to the planar image, i.e., the first side of the optical imaging lens group. It should be noted that this is in conjunction with reference to... Figures 1a to 2b ( Figure 2b Taking an optical imaging lens assembly containing six lenses as an example, the lens surface closest to and opposite the exit pupil position (i.e., the lens surface closest to the curved image) among the multiple lenses is concave. The optical axis and the concave surface intersect to form an intersection point. The distance between the intersection point and the exit pupil position is the exit pupil distance, which is 1.5-6.0 mm, preferably 2-3.5 mm. It should be noted that by defining the lens surface structure and corresponding exit pupil distance of the multiple coaxial lenses in the optical imaging lens assembly that are closest to the curved image, it can be matched with the corresponding curved scan image, thereby achieving clear imaging from the curved image to the planar image.

[0078] Additionally, further explanation is needed; please continue to refer to [the provided text]. Figure 2b :

[0079] Entrance pupil: The entrance pupil is the effective aperture that restricts the incident light beam. It is the image formed by the aperture stop on the optical system in front of it. It is the conjugate phase of the aperture stop in object space. The entrance pupil and the exit pupil are opposites.

[0080] Entrance pupil position: The entrance pupil position is the position point where the aperture stop forms an image of the optical system in front. The entrance pupil position is calculated by taking the center of the aperture stop as an object point, tracing the light rays in front of the optical system, and obtaining the coordinates of the intersection point with the optical axis. Usually, the distance from the surface of the first lens is used as the entrance pupil distance.

[0081] Exit pupil: The image formed by the aperture stop of an optical system in the image space of the optical system is the exit pupil of the lens;

[0082] Exit pupil position: The exit pupil position is the position point where the aperture stop images the rear optical system. The exit pupil position is calculated by taking the center of the aperture stop as an object point, tracing the light rays towards the rear optical system, and obtaining the coordinates of the intersection point with the point on the optical axis. Usually, the distance from the last lens surface is used as the exit pupil distance.

[0083] Measurement of exit pupil position: Set a point light source at the center of the entrance pupil position, and image through the designed lens. The optimal imaging position of the point light source is the exit pupil position.

[0084] More specifically, such as Figure 2b As shown, from left to right, that is, from the first side to the second side, are the entrance pupil (entrance pupil position), the optical imaging lens group, and the exit pupil (exit pupil position).

[0085] Example One

[0086] Figure 3 This is a schematic diagram of an optical imaging lens assembly provided in an embodiment of the present invention. The optical imaging lens assembly includes a first side (i.e., Figure 3 From the side where aperture 01 is located to the second side (that is, Figure 3 The first lens 11, the second lens 12, the third lens 13, the fourth lens 14, and the fifth lens 15 are arranged sequentially along the common optical axis on the side where the scanning surface 02 is located.

[0087] In this embodiment, there is a gap between each pair of adjacent lenses in the first lens 11, the second lens 12, the third lens 13, the fourth lens 14, and the fifth lens 15. The first lens 11, the second lens 12, the third lens 13, the fourth lens 14, and the fifth lens 15 are five single non-bonded lenses.

[0088] The focal lengths of the first lens 11 to the fifth lens 15, from the first side to the second side, are negative, positive, positive, negative, and positive, respectively.

[0089] The first side surface of the first lens 11 is convex, and the second side surface is concave near the optical axis.

[0090] Both the first and second side surfaces of the second lens 12 are convex.

[0091] The first side surface of the third lens 13 is concave, and the second side surface is convex.

[0092] The first side surface of the fourth lens 14 is concave, and the second side surface is convex.

[0093] The first side surface of the fifth lens 15 is convex, and the second side surface is concave near the optical axis.

[0094] In this embodiment, the focal lengths of the first lens 11 to the fifth lens 15 in the optical imaging lens group satisfy the following relationship:

[0095] f1 / f is -0.69, f2 / f is 0.41, f3 / f is 0.99, f4 / f is -0.39 and f5 / f is 0.44; where f1 is the focal length of the first lens 11, f2 is the focal length of the second lens 12, f3 is the focal length of the third lens 13, f4 is the focal length of the fourth lens 14, f5 is the focal length of the fifth lens 15, and f is the equivalent focal length of the optical imaging lens group.

[0096] The refractive index and dispersion coefficient of the first lens 11 to the fifth lens 15 in the optical imaging lens group satisfy the following conditions:

[0097] n1 is 1.55, n2 is 1.61, n3 is 1.49, n4 is 1.76, and n5 is 1.62. Here, n1 to n5 represent the refractive indices of the first lens 11 to the fifth lens 15, respectively; the Abbe number of the first lens is 47.3, the Abbe number of the second lens is 60.7, the Abbe number of the third lens is 70.4, the Abbe number of the fourth lens is 27.6, and the Abbe number of the fifth lens is 60.3.

[0098] In the optical imaging lens assembly provided in Embodiment 1 of the present invention, the overall equivalent focal length of the optical imaging lens assembly is 2.60 mm, the aperture value is 1.3, the half field of view is 10 degrees, the scanning radius is 2 mm, and the entrance pupil diameter is 2 mm. The preferred parameters for the curvature radius, thickness, refractive index, and dispersion coefficient of each lens used to image the scanning surface O2 are shown in Table 1.

[0099] Table 1. Structural parameters of the optical imaging lens assembly in Example 1

[0100] Surface Lens Number Surface Shape Radius of Curvature Thickness / Spacing Material Refractive Index Dispersion Coefficient 0 Imaging Plane Plane Infinity Infinity 1 Stop 01 Infinity 1 2 First Lens 11 Aspheric 2.73 1.72 1.55 47.3 3 Aspheric 0.56 0.15 4 Second Lens 12 Aspheric 0.67 1.23 1.61 60.7 5 Aspheric -7.82 0.34 6 Third Lens 13 Aspheric -2.54 0.90 1.49 70.4 7 Aspheric -0.94 0.19 8 Fourth Lens 14 Aspheric -0.39 0.60 1.76 27.6 9 Aspheric -1.31 0.10 10 Fifth Lens 15 Aspheric 0.59 1.08 1.62 60.3 11 Aspheric 1.06 0.50 12 Scanning Surface 02 Spherical 2

[0101] It should be noted that Table 1 contains detailed structural data of the optical imaging lens group in Embodiment 1. The units for radius of curvature, thickness and focal length are all millimeters, and surfaces 0-12 sequentially represent the surfaces from the first side to the second side; an optical surface with an "infinite" radius of curvature in the imaging plane refers to a plane.

[0102] Furthermore, the aspherical conic coefficients of the surfaces corresponding to the first lens 11 to the fifth lens 15 are shown in Table 2 below:

[0103] Table 2. Aspheric conic coefficient data for different lens surfaces in Example 1.

[0104]

[0105]

[0106] Table 2 shows the aspheric coefficient data in Example 1, where k is the conical coefficient in the aspheric curve equation, and A4 to A8 represent the 4th to 8th order aspheric coefficients of each surface.

[0107] Furthermore, tests showed that when the image light corresponding to the scanning surface is projected using the aforementioned optical imaging lens group, its optical transfer function curve is as follows: Figure 4 As shown, the field distortion curve is as follows: Figure 5 As shown, the vertical axis color difference curve is as follows: Figure 6As shown; among them, the Modulation Transfer Function (MTF) curve represents the overall resolution level of an optical system, the Field Curve Distortion curve represents the F-Tan (theta) distortion magnitude (percentage) under different field angles, and the Vertical Chromatic Aberration curve represents the magnitude of chromatic aberration in the direction perpendicular to the axial direction.

[0108] Depend on Figures 4-6 Observations show that the optical imaging lens group in Example 1 has good imaging resolution, small optical system distortion and chromatic aberration across the entire field of view. Therefore, the optical imaging lens group can clearly image the scanning surface image of the fiber optic scanner and has good imaging effect.

[0109] Of course, in practical applications, the optical imaging lens assembly may also include a display element, a housing, etc. The display element can be set on the second side of the optical imaging lens assembly, and the optical imaging lens assembly can be installed in the housing, so that the curved image formed by the image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0110] Example Two

[0111] Figure 7 This is a schematic diagram of an optical imaging lens assembly provided in an embodiment of the present invention. The optical imaging lens assembly includes a first side (i.e., Figure 7 From the side where aperture 03 is located (i.e., the second side) to the third side (i.e., Figure 7 The first lens 31, the second lens 32, the third lens 33, the fourth lens 34, and the fifth lens 35 are arranged sequentially along the common optical axis on the side where the scanning surface 04 is located.

[0112] In this embodiment, there is a gap between each pair of adjacent lenses in the first lens 31, the second lens 32, the third lens 33, the fourth lens 34, and the fifth lens 35. The first lens 31, the second lens 32, the third lens 33, the fourth lens 34, and the fifth lens 35 are five single non-bonded lenses.

[0113] The focal lengths of the first lens 31 to the fifth lens 35, from the first side to the second side, are negative, positive, positive, negative, and positive, respectively.

[0114] The first side surface of the first lens 31 is convex, and the second side surface is concave near the optical axis.

[0115] The first side surface of the second lens 32 is convex near the optical axis, and the second side surface is concave near the optical axis.

[0116] The first and second side surfaces of the third lens 33 are both convex.

[0117] The first side surface of the fourth lens 34 is concave, and the second side surface is convex.

[0118] The first side surface of the fifth lens 35 is convex, and the second side surface is concave near the optical axis.

[0119] In this embodiment, the focal lengths of the first lens 31 to the fifth lens 35 in the optical imaging lens group satisfy the following relationship:

[0120] f1 / f is -1.29, f2 / f is 0.75, f3 / f is 0.76, f4 / f is -0.38, and f5 / f is 0.44; where f1 is the focal length of the first lens 31, f2 is the focal length of the second lens 32, f3 is the focal length of the third lens 33, f4 is the focal length of the fourth lens 34, f5 is the focal length of the fifth lens 35, and f is the equivalent focal length of the optical imaging lens group.

[0121] The refractive indices and dispersion coefficients of the first lens 31 to the fifth lens 35 in the optical imaging lens group satisfy the following conditions:

[0122] n1 is 1.53, n2 is 1.49, n3 is 1.57, n4 is 1.76, and n5 is 1.62. Here, n1 to n5 represent the refractive indices of the first lens 31 to the fifth lens 35, respectively; the Abbe number of the first lens is 52.8, the Abbe number of the second lens is 70.2, the Abbe number of the third lens is 63.6, the Abbe number of the fourth lens is 27.6, and the Abbe number of the fifth lens is 60.3.

[0123] In the optical imaging lens assembly provided in Embodiment 2 of the present invention, the overall equivalent focal length of the optical imaging lens assembly is 2.6 mm, the aperture value is 1.30, the half field of view is 10 degrees, the scanning radius is 2 mm, and the entrance pupil diameter is 2 mm. The preferred parameters for the radius of curvature, thickness, refractive index, and dispersion coefficient of each lens used to image the scanning surface 04 are shown in Table 3.

[0124] Table 3 Structural parameters of the optical imaging lens assembly in Example 2

[0125] Surface Lens Number Surface Shape Radius of Curvature Thickness / Spacing Material Refractive Index Dispersion Coefficient 0 Imaging Plane Plane Infinity Infinity 1 Stop 03 Infinity 1 2 First Lens 31 Aspheric 1.80 1.42 1.53 52.8 3 Aspheric 0.65 0.34 4 Second Lens 32 Aspheric 0.85 1.03 1.49 70.2 5 Aspheric 4.46 0.10 6 Third Lens 33 Aspheric 2.90 1.15 1.57 63.6 7 Aspheric -1.56 0.27 8 Fourth Lens 34 Aspheric -0.45 0.74 1.76 27.6 9 Aspheric -1.87 0.10 10 Fifth Lens 35 Aspheric 0.60 1.08 1.62 60.3 11 Aspheric 1.11 0.50 12 Scanning Surface 04 Spherical 2

[0126] It should be noted that Table 3 contains detailed structural data of the optical imaging lens group in Embodiment 2. The units for radius of curvature, thickness and focal length are all millimeters, and surfaces 0-12 sequentially represent the surfaces from the first side to the second side; an optical surface with an "infinite" radius of curvature in the imaging plane refers to a plane.

[0127] Furthermore, the aspherical conic coefficients of the surfaces corresponding to the first lens 31 to the fifth lens 35 are shown in Table 4 below:

[0128] Table 4. Aspheric conic coefficient data for different lens surfaces in Example 2.

[0129] Surface K A4 A6 A8 2 -4.14E+00 4.40E-02 -6.71E-03 3.42E-03 3 -2.40E+00 7.09E-02 -5.65E-02 2.86E-02 4 -8.42E-01 -3.82E-01 1.52E-01 -1.83E-01 5 1.28E+01 -1.53E-01 5.23E-02 -5.30E-02 6 3.92E+00 -9.13E-02 1.53E-01 -9.24E-02 7 -1.73E+01 -9.52E-02 4.44E-02 -1.81E-02 8 -3.81E+00 3.16E-02 1.71E-03 2.20E-03 9 -2.77E+01 -1.74E-01 2.14E-01 -7.12E-02 10 -1.53E+00 -1.12E-01 2.24E-01 -2.15E-01 11 -7.27E-01 -2.20E-01 -9.62E-01 9.60E-01

[0130] Table 4 shows the aspheric coefficient data in Example 2, where k is the conical coefficient in the aspheric curve equation, and A4 to A8 represent the 4th to 8th order aspheric coefficients of each surface.

[0131] Furthermore, tests showed that when the image light corresponding to the scanning surface is projected using the aforementioned optical imaging lens group, its optical transfer function curve is as follows: Figure 8 As shown, the field distortion curve is as follows: Figure 9 As shown, the vertical axis color difference curve is as follows: Figure 10 As shown; among them, the Modulation Transfer Function (MTF) curve represents the overall resolution level of an optical system, the Field Curve Distortion curve represents the F-Tan (theta) distortion magnitude (percentage) under different field angles, and the Vertical Chromatic Aberration curve represents the magnitude of chromatic aberration in the direction perpendicular to the axial direction.

[0132] Depend on Figures 8-10 Observations show that the optical imaging lens group of Example 2 has good imaging resolution and small optical system distortion and chromatic aberration across the entire field of view. Therefore, the optical imaging lens group can clearly image the scanning surface image of the fiber optic scanner and has good imaging effect.

[0133] Of course, in practical applications, the optical imaging lens assembly may also include a display element, a housing, etc. The display element can be set on the second side of the optical imaging lens assembly, and the optical imaging lens assembly can be installed in the housing, so that the curved image formed by the image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0134] Example Three

[0135] Figure 11 This is a schematic diagram of an optical imaging lens assembly provided in an embodiment of the present invention. The optical imaging lens assembly includes a first side (i.e., Figure 11 From the side where aperture 05 is located (to the second side, that is, Figure 11 The first lens 51, the second lens 52, the third lens 53, the fourth lens 54, and the fifth lens 55 are arranged sequentially along the common optical axis on the side where the scanning surface 06 is located.

[0136] In this embodiment, there is a gap between each pair of adjacent lenses in the first lens 51, the second lens 52, the third lens 53, the fourth lens 54, and the fifth lens 55. The first lens 51, the second lens 52, the third lens 53, the fourth lens 54, and the fifth lens 55 are five single non-bonded lenses.

[0137] The focal lengths of the first lens 51 to the fifth lens 55, from the first side to the second side, are negative, positive, positive, negative, and positive, respectively.

[0138] The first side surface of the first lens 51 is convex, and the second side surface is concave near the optical axis.

[0139] The first side surface of the second lens 52 is convex, and the second side surface is concave.

[0140] Both the first and second side surfaces of the third lens 53 are convex.

[0141] The first side surface of the fourth lens 54 is concave, and the second side surface is convex near the optical axis.

[0142] The first side surface of the fifth lens 55 is convex, and the second side surface is concave near the optical axis.

[0143] In this embodiment, the focal lengths of the first lens 51 to the fifth lens 55 in the optical imaging lens group satisfy the following relationship:

[0144] f1 / f is -1.17, f2 / f is 5.26, f3 / f is 0.38, f4 / f is -0.62, and f5 / f is 0.65; where f1 is the focal length of the first lens 51, f2 is the focal length of the second lens 52, f3 is the focal length of the third lens 53, f4 is the focal length of the fourth lens 54, f5 is the focal length of the fifth lens 55, and f is the equivalent focal length of the optical imaging lens group.

[0145] The refractive index and dispersion coefficient of the first lens 51 to the fifth lens 55 in the optical imaging lens group satisfy the following conditions:

[0146] n1 is 1.72, n2 is 1.68, n3 is 1.55, n4 is 1.73, and n5 is 1.62. Here, n1 to n5 represent the refractive indices of the first lens 51 to the fifth lens 55, respectively; the Abbe number of the first lens is 31.8, the Abbe number of the second lens is 34.5, the Abbe number of the third lens is 64.7, the Abbe number of the fourth lens is 29.5, and the Abbe number of the fifth lens is 60.3.

[0147] In the optical imaging lens assembly provided in Embodiment 3 of the present invention, the overall equivalent focal length of the optical imaging lens assembly is 2.6 mm, the aperture value is 1.30, the half field of view is 10 degrees, the scanning radius is 2 mm, and the entrance pupil diameter is 2 mm. The preferred parameters for the radius of curvature, thickness, refractive index, and dispersion coefficient of each lens used to image the scanning surface 06 are shown in Table 5.

[0148] Table 5 Structural parameters of the optical imaging lens assembly in Example 3

[0149] Surface Lens Number Surface Shape Radius of Curvature Thickness / Spacing Material Refractive Index Dispersion Coefficient 0 Imaging Plane Plane Infinity Infinity 1 Stop 05 Infinity 1 2 First Lens 51 Aspheric 2.14 1.30 1.72 31.8 3 Aspheric 0.81 0.45 4 Second Lens 52 Aspheric 0.82 0.91 1.68 34.5 5 Aspheric 0.49 0.12 6 Third Lens 53 Aspheric 0.56 1.48 1.55 64.7 7 Aspheric -1.38 0.21 8 Fourth Lens 54 Aspheric -0.49 0.79 1.73 29.5 9 Aspheric -1.39 0.16 10 Fifth Lens 55 Aspheric 0.80 1.22 1.62 60.3 11 Aspheric 1.40 0.50 12 Scanning Surface 06 Spherical 2

[0150] It should be noted that Table 5 contains detailed structural data of the optical imaging lens group in Embodiment 3. The units for radius of curvature, thickness and focal length are all millimeters, and surfaces 0-12 sequentially represent the surfaces from the first side to the second side; an optical surface with an "infinite" radius of curvature in the imaging plane refers to a plane.

[0151] Furthermore, the aspherical conic coefficients of the surfaces corresponding to the first lens 51 to the fifth lens 55 are shown in Table 6 below:

[0152] Table 6. Aspheric conic coefficient data for different lens surfaces in Example 3.

[0153] Surface K A4 A6 A8 2 -6.35E+00 4.21E-02 -7.81E-03 3.18E-03 3 -3.94E+00 1.33E-01 -1.15E-01 8.50E-02 4 -2.84E+00 -1.70E-02 1.09E-02 -3.27E-02 5 -3.59E+00 -1.01E-01 1.07E-01 -4.96E-02 6 -3.64E+00 -1.53E-01 1.29E-01 -3.55E-02 7 -1.16E+01 -1.04E-01 1.31E-02 8.65E-03 8 -3.40E+00 1.25E-01 -8.96E-03 -1.75E-03 9 -8.83E+00 -9.46E-02 1.76E-01 -2.73E-02 10 -8.89E-01 -2.82E-01 1.76E-02 6.45E-02 11 -4.03E+00 -7.75E-01 8.41E-01 -1.71E-01

[0154] Table 6 shows the aspheric coefficient data in Example 3, where k is the conical coefficient in the aspheric curve equation, and A4 to A8 represent the 4th to 8th order aspheric coefficients of each surface.

[0155] Furthermore, tests showed that when the image light corresponding to the scanning surface is projected using the aforementioned optical imaging lens group, its optical transfer function curve is as follows: Figure 12 As shown, the field distortion curve is as follows: Figure 13 As shown, the vertical axis color difference curve is as follows: Figure 14 As shown; among them, the Modulation Transfer Function (MTF) curve represents the overall resolution level of an optical system, the Field Curve Distortion curve represents the F-Tan (theta) distortion magnitude (percentage) under different field angles, and the Vertical Chromatic Aberration curve represents the magnitude of chromatic aberration in the direction perpendicular to the axial direction.

[0156] Depend on Figures 12-14 Observations show that the optical imaging lens group in Example 3 has good imaging resolution, small optical system distortion and chromatic aberration across the entire field of view. Therefore, the optical imaging lens group can clearly image the scanning surface image of the fiber optic scanner and has good imaging effect.

[0157] Of course, in practical applications, the optical imaging lens assembly may also include a display element, a housing, etc. The display element can be set on the second side of the optical imaging lens assembly, and the optical imaging lens assembly can be installed in the housing, so that the curved image formed by the image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0158] Example Four

[0159] Figure 15 This is a schematic diagram of an optical imaging lens assembly provided in an embodiment of the present invention. The optical imaging lens assembly includes a first side (i.e., Figure 15From the side where aperture 07 is located to the second side (that is, Figure 15 The first lens 71, second lens 72, third lens 73, fourth lens 74, fifth lens 75, and sixth lens 76 are arranged sequentially along the common optical axis on the side where the scanning surface 08 is located. It should be noted that the first lens 71 provided in this embodiment is equivalent to an additional lens, and the positive and negative focal lengths of the second lens 72, third lens 73, fourth lens 74, fifth lens 75, and sixth lens 76 correspond to the positive and negative focal lengths of the five lenses defined in the claims. The terms "first," "second," etc., in the embodiments do not indicate the importance or order of the lenses, but are simply used to distinguish different components.

[0160] In this embodiment, there is a gap between each pair of adjacent lenses in the first lens 71, the second lens 72, the third lens 73, the fourth lens 74, the fifth lens 75, and the sixth lens 76. The first lens 71, the second lens 72, the third lens 73, the fourth lens 74, the fifth lens 75, and the sixth lens 76 are six single non-bonded lenses.

[0161] The focal lengths of the first lens 71 to the sixth lens 76, from the first side to the second side, are positive, negative, positive, positive, negative, and positive, respectively.

[0162] The first side surface of the first lens 71 is concave near the optical axis, and the second side surface is convex.

[0163] The first side surface of the second lens 72 is convex, and the second side surface is concave near the optical axis.

[0164] The first side surface of the third lens 73 is convex, and the second side surface is concave.

[0165] The first and second side surfaces of the fourth lens 74 are both convex.

[0166] The first side surface of the fifth lens 75 is concave, and the second side surface is convex near the optical axis.

[0167] The first side surface of the sixth lens 76 is convex, and the second side surface is concave near the optical axis.

[0168] In this embodiment, the focal lengths of the first lens 71 to the sixth lens 76 in the optical imaging lens group satisfy the following relationship:

[0169] f1 / f is 8.48, f2 / f is -2.09, f3 / f is 1.28, f4 / f is 0.79, f5 / f is -0.52 and f6 / f is 0.61; where f1 is the focal length of the first lens 71, f2 is the focal length of the second lens 72, f3 is the focal length of the third lens 73, f4 is the focal length of the fourth lens 74, f5 is the focal length of the fifth lens 75, f6 is the focal length of the sixth lens 76, and f is the equivalent focal length of the optical imaging lens group.

[0170] The refractive indices and dispersion coefficients of the first lens 71 to the sixth lens 76 in the optical imaging lens group satisfy the following conditions:

[0171] n1 is 1.69, n2 is 1.76, n3 is 1.62, n4 is 1.62, n5 is 1.76, and n6 is 1.69. Here, n1 to n6 represent the refractive indices of the first lens 71 to the sixth lens 76, respectively; the Abbe number of the first lens is 49.4, the Abbe number of the second lens is 27.6, the Abbe number of the third lens is 60.3, the Abbe number of the fourth lens is 60.3, the Abbe number of the fifth lens is 27.6, and the Abbe number of the sixth lens is 49.4.

[0172] In the optical imaging lens assembly provided in Embodiment 4 of the present invention, the overall equivalent focal length of the optical imaging lens assembly is 2.6 mm, the aperture value is 1.30, the half field of view is 10 degrees, the scanning radius is 2 mm, and the entrance pupil diameter is 2 mm. The preferred parameters of the curvature radius, thickness parameters, refractive index, and dispersion coefficient of each lens for imaging the scanning surface 08 are shown in Table 7.

[0173] Table 7 Structural parameters of the optical imaging lens assembly in Example 4

[0174] Surface Lens Number Surface Shape Radius of Curvature Thickness / Spacing Material Refractive Index Dispersion Coefficient 0 Imaging Plane Plane Infinity Infinity 1 Stop 07 Infinity 1 2 First Lens 71 Spherical -2.12 0.82 1.69 49.4 3 Spherical -2.16 0.10 4 Second Lens 72 Aspheric 1.45 0.63 1.76 27.6 5 Aspheric 0.87 0.98 6 Third Lens 73 Aspheric 1.38 1.42 1.62 60.3 7 Aspheric 2.56 0.19 8 Fourth Lens 74 Aspheric 4.14 1.27 1.62 60.3 9 Aspheric -1.62 0.14 10 Fifth Lens 75 Aspheric -0.84 1.19 1.76 27.6 11 Aspheric -8.07 0.18 12 Sixth Lens 76 Aspheric 0.75 0.95 1.69 49.4 13 Aspheric 1.17 0.50 14 Scanning Surface 08 Spherical 2

[0175] It should be noted that Table 7 contains detailed structural data of the optical imaging lens group in Embodiment 4. The units for radius of curvature, thickness and focal length are all millimeters, and surfaces 0-14 sequentially represent the surfaces from the first side to the second side; an optical surface with an "infinite" radius of curvature in the imaging plane refers to a plane.

[0176] Furthermore, the aspherical conic coefficients of the surfaces corresponding to the first lens 71 to the sixth lens 76 are shown in Table 8 below:

[0177] Table 8. Aspheric conic coefficient data for different lens surfaces in Example 4.

[0178]

[0179]

[0180] Table 8 shows the aspheric coefficient data in Example 4, where k is the conical coefficient in the aspheric curve equation, and A4 to A8 represent the 4th to 8th order aspheric coefficients of each surface.

[0181] Furthermore, tests showed that when the image light corresponding to the scanning surface is projected using the aforementioned optical imaging lens group, its optical transfer function curve is as follows: Figure 16 As shown, the field distortion curve is as follows: Figure 17 As shown, the vertical axis color difference curve is as follows: Figure 18 As shown; among them, the Modulation Transfer Function (MTF) curve represents the overall resolution level of an optical system, the Field Curve Distortion curve represents the F-Tan (theta) distortion magnitude (percentage) under different field angles, and the Vertical Chromatic Aberration curve represents the magnitude of chromatic aberration in the direction perpendicular to the axial direction.

[0182] Depend on Figures 16-18 Observations show that the optical imaging lens group in Example 4 has good imaging resolution and small optical system distortion and chromatic aberration across the entire field of view. Therefore, the optical imaging lens group can clearly image the scanning surface image of the fiber optic scanner and has good imaging effect.

[0183] Of course, in practical applications, the optical imaging lens assembly may also include a display element, a housing, etc. The display element can be set on the second side of the optical imaging lens assembly, and the optical imaging lens assembly can be installed in the housing, so that the curved image formed by the image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0184] Example 5

[0185] Figure 19 This is a schematic diagram of an optical imaging lens assembly provided in an embodiment of the present invention. The optical imaging lens assembly includes a first side (i.e., Figure 19 From the side where aperture 09 is located (to the second side, that is, Figure 19 The first lens 91, the second lens 92, the third lens 93, the fourth lens 94, and the fifth lens 95 are arranged sequentially along the common optical axis on the side where the scanning surface 10 is located.

[0186] In this embodiment, there is a gap between each pair of adjacent lenses in the first lens 91, the second lens 92, the third lens 93, the fourth lens 94, and the fifth lens 95. The first lens 91, the second lens 92, the third lens 93, the fourth lens 94, and the fifth lens 95 are five single non-bonded lenses.

[0187] The focal lengths of the first lens 91 to the fifth lens 95, from the first side to the second side, are negative, positive, positive, negative, and positive, respectively.

[0188] The first side surface of the first lens 91 is convex, and the second side surface is concave near the optical axis.

[0189] The first side surface of the second lens 92 is convex, and the second side surface is concave.

[0190] The first and second side surfaces of the third lens 93 are both convex.

[0191] The first side surface of the fourth lens 94 is concave, and the second side surface is concave.

[0192] The first side surface of the fifth lens 95 is convex, and the second side surface is concave near the optical axis.

[0193] In this embodiment, the focal lengths of the first lens 91 to the fifth lens 95 in the optical imaging lens group satisfy the following relationship:

[0194] f1 / f is -2.25, f2 / f is 12.10, f3 / f is 0.46, f4 / f is -0.31 and f5 / f is 0.47; where f1 is the focal length of the first lens 91, f2 is the focal length of the second lens 92, f3 is the focal length of the third lens 93, f4 is the focal length of the fourth lens 94, f5 is the focal length of the fifth lens 95, and f is the equivalent focal length of the optical imaging lens group.

[0195] The refractive index and dispersion coefficient of the first lens 91 to the fifth lens 95 in the optical imaging lens group satisfy the following conditions:

[0196] n1 is 1.69, n2 is 1.68, n3 is 1.56, n4 is 1.69, and n5 is 1.68. Here, n1 to n5 represent the refractive indices of the first lens 91 to the fifth lens 95, respectively; the Abbe number of the first lens is 30.8, the Abbe number of the second lens is 31.4, the Abbe number of the third lens is 63.6, the Abbe number of the fourth lens is 30.8, and the Abbe number of the fifth lens is 51.5.

[0197] In the optical imaging lens assembly provided in this embodiment of the invention, the overall equivalent focal length of the optical imaging lens assembly is 2.6 mm, the aperture value is 1.30, the half field of view is 10 degrees, the scanning radius is 2 mm, and the entrance pupil diameter is 2 mm. The preferred parameters for the radius of curvature, thickness, refractive index, and dispersion coefficient of each lens used to image the scanning surface 10 are shown in Table 9.

[0198] Table 9 Structural parameters of the optical imaging lens assembly in Example 5

[0199] Surface Lens Number Surface Shape Radius of Curvature Thickness / Spacing Material Refractive Index Dispersion Coefficient 0 Imaging Plane Plane Infinity Infinity 1 Stop 09 Infinity 1 2 First Lens 51 Aspheric 1.39 0.81 1.69 30.8 3 Aspheric 0.79 0.90 4 Second Lens 52 Aspheric 1.14 0.69 1.68 31.4 5 Aspheric 0.91 0.13 6 Third Lens 53 Aspheric 1.06 1.43 1.56 63.6 7 Aspheric -0.95 0.14 8 Fourth Lens 54 Aspheric -0.58 1.44 1.69 30.8 9 Aspheric 36.60 0.12 10 Fifth Lens 55 Aspheric 0.70 1.20 1.68 51.5 11 Aspheric 1.47 0.50 12 Scanning Surface 10 Spherical 2

[0200] It should be noted that Table 9 contains detailed structural data of the optical imaging lens group in Embodiment 5. The units for radius of curvature, thickness and focal length are all millimeters, and surfaces 0-12 sequentially represent the surfaces from the first side to the second side; an optical surface with an "infinite" radius of curvature in the imaging plane refers to a plane.

[0201] Furthermore, the aspherical conic coefficients of the surfaces corresponding to the first lens 91 to the fifth lens 95 are shown in Table 10 below:

[0202] Table 10. Aspheric conic coefficient data for different lens surfaces in Example 5

[0203] Surface K A4 A6 A8 2 -3.35E+00 6.08E-02 -1.45E-02 7.92E-03 3 -2.85E+00 1.27E-01 -8.90E-02 7.08E-02 4 -2.78E+00 -6.52E-02 -3.69E-03 -2.04E-02 5 -3.70E+00 -1.27E-01 1.10E-01 -4.60E-02 6 -3.33E+00 -1.19E-01 1.23E-01 -4.00E-02 7 -1.02E+01 -7.65E-02 2.96E-02 -5.38E-03 8 -4.98E+00 1.14E-01 -4.95E-02 1.02E-02 9 -3.48E+01 6.94E-02 -3.75E-02 7.79E-03 10 -7.37E-01 -2.47E-01 1.79E-01 -1.03E-01 11 2.73E+00 -2.17E-01 3.79E-01 -1.22E+00

[0204] Table 10 shows the aspheric coefficient data in Example 5, where k is the conical coefficient in the aspheric curve equation, and A4 to A8 represent the 4th to 8th order aspheric coefficients of each surface.

[0205] Furthermore, tests showed that when the image light corresponding to the scanning surface is projected using the aforementioned optical imaging lens group, its optical transfer function curve is as follows: Figure 20 As shown, the field distortion curve is as follows: Figure 21 As shown, the vertical axis color difference curve is as follows: Figure 22 As shown; among them, the Modulation Transfer Function (MTF) curve represents the overall resolution level of an optical system, the Field Curve Distortion curve represents the F-Tan (theta) distortion magnitude (percentage) under different field angles, and the Vertical Chromatic Aberration curve represents the magnitude of chromatic aberration in the direction perpendicular to the axial direction.

[0206] Depend on Figures 20-22 Observations show that the optical imaging lens group in Example 5 has good imaging resolution and small optical system distortion and chromatic aberration across the entire field of view. Therefore, the optical imaging lens group can clearly image the scanning surface image of the fiber optic scanner and has good imaging effect.

[0207] Of course, in practical applications, the optical imaging lens assembly may also include a display element, a housing, etc. The display element can be set on the second side of the optical imaging lens assembly, and the optical imaging lens assembly can be installed in the housing, so that the curved image formed by the image source (such as a fiber optic scanner) can be imaged on a plane to achieve clear imaging.

[0208] Scanning display device

[0209] The aforementioned optical imaging lens assembly can be used in conjunction with a fiber optic scanner (or a corresponding fiber optic scanning module) to constitute the scanning display device in the embodiments of this application (e.g., Figure 1a , 1bAs shown, the optical imaging lens group is positioned on the output optical path of the fiber optic scanner. The first side of the optical imaging lens group faces the scanning output direction of the fiber optic scanner. Preferably, the optical imaging lens group is coaxial with the central optical axis of the fiber optic scanner. Of course, the structure and general principle of the fiber optic scanner can be found in the aforementioned... Figure 1a , 1b The corresponding content will not be elaborated on here.

[0210] Near-eye display device

[0211] In this application, the scanning display device can be further applied to a near-eye display device, and can be used in conjunction with a near-eye display module to form the near-eye display device in the embodiments of this application, for use as a head-mounted AR device (such as AR glasses). The scanning display device is disposed in the near-eye display module.

[0212] The near-eye display module may include: a light source, processing and control circuitry, a wearable frame structure, and a waveguide. The image beam output from the light source enters the scanning display device, where it is scanned by a fiber optic scanner and output to the optical display lens assembly. The scanning surface of the fiber optic scanner (see reference) Figure 3 The scan surface 02 and its corresponding Figure 2a The scanning surface 230 in the image is converted into an imaging plane after passing through the optical display lens group (see reference). Figure 2a The imaging plane 240 in the waveguide is coupled into the waveguide as the entrance pupil surface, and then coupled out through the waveguide to enter the human eye.

[0213] As another possible implementation, the scanning display device can be further combined with the near-eye display module to form the near-eye display device in the embodiments of this application, and used as a head-mounted VR device (such as a VR helmet / glasses). The scanning display device is disposed in the near-eye display module.

[0214] In this embodiment, by rationally optimizing the focal length of the five coaxial lenses in the optical imaging lens group, the optical power of the system can be reasonably dispersed, the aberrations generated by the lenses can be reduced, and the purpose of correcting various aberrations can be achieved. While improving the field of view, clear imaging of the image surface is achieved. By limiting and optimizing the refractive index, dispersion coefficient, and surface structure of the five coaxial lenses, the imaging quality and field of view are further improved. By limiting and optimizing the design of the five coaxial lenses into aspherical surface structures, the overall structure of the optical imaging lens group is more compact while further improving the imaging quality, thus meeting the production requirements for miniaturization of lens products.

[0215] The above descriptions are merely preferred embodiments of this application. Each embodiment is only used to illustrate the technical solution of this application and is not intended to limit this application. Any technical solution that can be obtained by those skilled in the art through logical analysis, reasoning, or effective experiments based on the concept of this application should be within the scope of this application.

[0216] The various embodiments in this application are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0217] The terms "first," "second," "first," or "second" as used in the various embodiments of this disclosure may modify various components regardless of their order and / or importance, but these terms do not limit the corresponding components. The above terms are configured only for the purpose of distinguishing an element from other elements. For example, a first lens and a second lens represent different lenses, although both are lenses.

Claims

1. An optical imaging lens assembly, characterized in that, The first side of the optical imaging lens group corresponds to a planar image, and the second side corresponds to a curved image. The curved image is an arc-shaped scanning surface scanned by a fiber optic scanner or emitted by other image sources. The optical imaging lens group includes at least a first lens, a second lens, a third lens, a fourth lens, and a fifth lens arranged coaxially from the first side to the second side. The focal lengths corresponding to the first lens to the fifth lens are negative, positive, positive, negative, and positive, respectively. Each of the lenses satisfies the following relationship: -2.3 ≤ f 1 / f≤-0.7, 0.41≤f2 / f≤12.1, 0.38≤f3 / f≤0.99, -0.6≤f4 / f≤-0.3, and 0.44≤f5 / f≤0.65, where f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, f5 is the focal length of the fifth lens, and f is the focal length of the optical imaging lens group; the exit pupil distance of the optical imaging lens group is 1.5-6.0mm.

2. The optical imaging lens assembly as described in claim 1, characterized in that, The second side surface of the fifth lens is concave near the optical axis.

3. The optical imaging lens assembly as described in claim 2, characterized in that, The various lenses satisfy the following relationships: 1.53≤n1≤1.72, 1.49≤n2≤1.68, 1.49≤n3≤1.57, 1.69≤n4≤1.76, 1.62≤n5≤1.68; where n1 is the refractive index of the first lens, n2 is the refractive index of the second lens, n3 is the refractive index of the third lens, n4 is the refractive index of the fourth lens, and n5 is the refractive index of the fifth lens; The dispersion coefficients of the various lenses satisfy the following: 30.8≤v1≤47.3, 31.4≤v2≤70.2, 63.6≤v3≤70.4, 27.6≤v4≤30.8, 51.5≤v5≤60.3; where v1 is the Abbe number of the first lens, v2 is the Abbe number of the second lens, v3 is the Abbe number of the third lens, v4 is the Abbe number of the fourth lens, and v5 is the Abbe number of the fifth lens.

4. The optical imaging lens assembly as described in claim 3, characterized in that, The n1 is 1.53, 1.55, 1.69, or 1.72; the n2 is 1.49, 1.61, or 1.68; the n3 is 1.49, 1.55, 1.56, or 1.57; the n4 is 1.69, 1.73, 1.75, or 1.76; and the n5 is 1.62 or 1.

68. The dispersion coefficients of the various lenses satisfy the following conditions: the Abbe number of the first lens is 30.8, 31.8, 47.3, or 52.8; the Abbe number of the second lens is 31.4, 34.5, 60.7, or 70.2; the Abbe number of the third lens is 63.6, 64.7, or 70.4; the Abbe number of the fourth lens is 27.6, 29.5, or 30.8; and the Abbe number of the fifth lens is 51.5 or 60.

3.

5. The optical imaging lens assembly as described in claim 2, characterized in that, The first side surface of the fifth lens is convex; the first side surface of the fourth lens is concave; and the second side surface of the fourth lens is either convex or concave.

6. The optical imaging lens assembly as described in any one of claims 1 to 5, characterized in that, The first side surface of the third lens is concave or convex, and the second side surface of the third lens is convex.

7. The optical imaging lens assembly as described in claim 6, characterized in that, The first side surface of the first lens is convex, and the second side surface of the first lens is concave near the optical axis; the first side surface of the second lens is convex, and the second side surface of the second lens is either convex or concave. The first and second side surfaces of the first lens to the fifth lens are both aspherical surface structures.

8. A scanning display device, characterized in that, The system includes a fiber optic scanner and an optical imaging lens assembly according to any one of claims 1 to 7. The fiber optic scanner is used to scan and emit light to display an image, and the optical imaging lens assembly is used to magnify and project the scanning surface corresponding to the light emitted by the fiber optic scanner. The fiber optic scanner includes an actuator and an optical fiber fixed to the actuator. The portion of the optical fiber extending beyond the actuator forms an optical fiber cantilever, which performs two-dimensional scanning under the drive of the actuator.

9. A near-eye display device, characterized in that, The near-eye display device is used as a head-mounted augmented reality device, and includes at least a near-eye display module and a scanning display device according to claim 8, wherein the scanning display device is disposed in the near-eye display module.

10. A near-eye display device, characterized in that, The near-eye display device is used as a head-mounted virtual reality device, and includes at least a near-eye display module and a scanning display device according to claim 8, wherein the scanning display device is disposed in the near-eye display module.

Images