Optical lens and near-eye display device

Abstract

The present invention provides an optical lens and a near-eye display device, which include: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens in sequence along the reverse direction of light transmission; the first lens has positive focal power, and its light-emitting surface is a convex surface or a plane, and its light-entering surface is a convex surface; the second lens has focal power, and its light-emitting surface is a convex surface; the third lens has positive focal power, and its light-emitting surface is a convex surface, and its light-entering surface is a convex surface; the fourth lens has negative focal power, and its light-entering surface is a concave surface; the fifth lens has positive focal power, and its light-emitting surface is a convex surface; the sixth lens has negative focal power, and its light-entering surface is a concave surface; the seventh lens has focal power, and its light-emitting surface is a convex surface, and its light-entering surface is a concave surface; the distance CT between the light-entering surface of the seventh lens and the image source on the optical axis is W The optical lens provided by the present invention has the advantages of adjustable diopter and excellent imaging quality.

Description

Technical Field

[0001] The present invention relates to the technical field of imaging lenses, and in particular to an optical lens and a near-eye display device. Background Art

[0002] With the continuous advancement of optoelectronic devices and communication technology, virtual reality (VR) technology, as the forefront of the new generation of information technology, has achieved leapfrog development, and its forms and types are becoming increasingly diverse, and it is constantly being used in military, medical, education and consumer fields. Among them, head-mounted display devices usually transmit and amplify the information on the display screen through an optical system, and finally output it to the human eye. Therefore, the human eye receives the enlarged virtual image of the display screen, thereby achieving the purpose of large-screen viewing. At present, head-mounted display devices are developing in the direction of being more miniaturized, thinner, easier to wear, and larger screens. At the same time, large field of view, low distortion and visual comfort have also become key evaluation indicators for the quality of head-mounted displays. Large field of view and large screen display bring better immersion, and low distortion and high image quality determine the visual comfort.

[0003] In order to meet these requirements, the optical system needs to achieve indicators such as large field of view, low distortion, and high image quality at the same time. However, an increase in the field of view often leads to an increase in distortion. Therefore, meeting the above optical performance at the same time poses a huge challenge to the design of the optical system and the optimization of aberrations. At the same time, in order to meet the needs of users with different degrees of myopia or hyperopia, it is also necessary to have adjustable diopter. Moreover, there are currently few head-mounted display devices equipped with large display screens. Most of them are equipped with 0.49-inch or 0.71-inch or smaller display screens. The frame received by the human eye is small, and it is not possible to achieve an immersive viewing experience. Summary of the invention

[0004] In view of the above problems, the object of the present invention is to provide an optical lens having the advantages of adjustable diopter and excellent imaging quality.

[0005] The technical solution adopted by the present invention is:

[0006] An optical lens, composed of seven lenses, including: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens in order from the entrance pupil side of a human eye to the image source side along the reverse direction of light transmission; the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens each include a light entrance surface close to the image source side and a light exit surface close to the entrance pupil side of the human eye;

[0007] The first lens has positive power, the light exiting surface of the first lens is a convex surface or a plane, and the light incident surface of the first lens is a convex surface;

[0008] The second lens has optical power, and the light-emitting surface of the second lens is a convex surface;

[0009] The third lens has a positive optical power, the light-emitting surface of the third lens is convex, and the light-incident surface of the third lens is convex;

[0010] The fourth lens has a negative optical power, and the light-incident surface of the fourth lens is concave;

[0011] The fifth lens has a positive optical power, and the light-emitting surface of the fifth lens is convex;

[0012] The sixth lens has a negative optical power, and the light-incident surface of the sixth lens is concave;

[0013] The seventh lens has an optical power, the light-emitting surface of the seventh lens is convex, and the light-incident surface of the seventh lens is concave;

[0014] The distance CT on the optical axis between the light-incident surface of the seventh lens and the image source is adjustable; W within a range;

[0015] Wherein, the length IH of the display area of the image source that the optical lens can match and the effective focal length f of the optical lens satisfy: 1.2 < IH / f < 1.3;

[0016] The exit pupil distance ED of the optical lens and the effective focal length f of the optical lens satisfy: 0.42 < ED / f < 0.47.

[0017] Further preferably, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis and the sum ∑AT of the distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 5 < ∑CT / ∑AT < 10.

[0018] Further preferably, the effective focal length f of the optical lens and the combined focal length f12 of the first lens and the second lens satisfy: 0.8 < f12 / f < 4.

[0019] Further preferably, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 1 < f1 / f < 3; the radius of curvature R2 of the light-incident surface of the first lens and the effective focal length f of the optical lens satisfy: -5 < R2 / f < -0.5.

[0020] Further preferably, the second lens has a positive optical power, and the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 2 < f2 / f < 5.

[0021] Further preferably, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.5 < f3 / f < 4.5; the radius of curvature R5 of the light-emitting surface of the third lens and the radius of curvature R6 of the light-incident surface of the third lens satisfy: -0.35 < R5 / R6 < -0.01.

[0022] Further preferably, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -4 < f4 / f < -0.5.

[0023] Further preferably, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 2.5.

[0024] Further preferably, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -5 < f6 / f < -0.3.

[0025] Further preferably, the overall optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.29 < TTL / f < 1.4; the overall optical length TTL of the optical lens and the length IH of the display area of the image source that the optical lens can match satisfy: 1 < TTL / IH < 1.2.

[0026] The present invention also provides a near-eye display device, which sequentially includes, along the optical signal transmission direction: an image source, the above-mentioned optical lens; the image source is used for emitting an optical signal, and the optical signal includes image information; the optical lens is arranged in the light-emitting direction of the image source, and the seventh lens is arranged closer to the image source than the first lens, and the optical lens is used for modulating the optical signal emitted by the image source and transmitting it to the human eye.

[0027] Compared with the prior art, the optical lens provided by the present invention, through specific surface shape settings and reasonable optical power distribution, enables the optical lens to have a large field of view angle. The large field of view angle can provide a wide-field display effect, bringing a better experience to users; at the same time, the optical lens also has a large image plane and high resolution, and can match a display screen with a large size (1.33 inches) to achieve the viewing effect of a giant screen image. By adjusting the spatial interval distance between the entire lens group and the image source on the optical axis, a diopter adjustment from -7D to +2D can be achieved, and all have high imaging quality, bringing an excellent sensory experience to users. Description of the Drawings

[0028] The above and / or additional aspects and advantages of the present invention will become apparent and easy to understand from the following description of the embodiments in conjunction with the accompanying drawings, where:

[0029] Figure 1It is a schematic diagram of the structure of a near-eye display device provided in an embodiment of the present invention.

[0030] Figure 2 Schematic diagram of the structure of the optical lens provided in Example 1 of the present invention.

[0031] Figure 3 This is a field curvature curve diagram of the optical lens provided in Example 1 of the present invention.

[0032] Figure 4 This is a F-Tan(θ) distortion curve of the optical lens provided in Example 1 of the present invention.

[0033] Figure 5 Schematic diagram of the structure of the optical lens provided in Example 2 of the present invention.

[0034] Figure 6 This is a field curvature curve diagram of the optical lens provided in Example 2 of the present invention.

[0035] Figure 7 This is a F-Tan(θ) distortion curve of the optical lens provided in Example 2 of the present invention.

[0036] Figure 8 Schematic diagram of the structure of the optical lens provided in Example 3 of the present invention.

[0037] Fig. 9 This is a field curvature curve diagram of the optical lens provided in Example 3 of the present invention.

[0038] Fig.10 This is a F-Tan(θ) distortion curve diagram of the optical lens provided in Example 3 of the present invention.

[0039] Fig.11 This is a schematic diagram of the structure of the optical lens provided in Example 4 of the present invention.

[0040] Fig.12 This is a field curvature curve diagram of the optical lens provided in Example 4 of the present invention.

[0041] Fig.13 This is a F-Tan(θ) distortion curve of the optical lens provided in Example 4 of the present invention.

[0042] Fig.14 This is a schematic diagram of the optical path of the near-eye display device provided in Example 5 of the present invention.

[0043] The following specific implementation manner will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0044] In order to better understand the present application, a more detailed description will be made of various aspects of the present application with reference to the accompanying drawings. It should be understood that these detailed descriptions are only descriptions of the embodiments of the present application, and are not intended to limit the scope of the present application in any way. Throughout the specification, the same reference numerals refer to the same elements. The expression "and / or" includes any and all combinations of one or more of the associated listed items.

[0045] It should be noted that in this specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features. Therefore, without departing from the teaching of the present invention, the first lens discussed below may also be referred to as the second lens or the third lens.

[0046] In the drawings, the thickness, size and shape of the lenses have been slightly exaggerated for ease of explanation. Specifically, the shapes of the spherical or aspherical surfaces shown in the drawings are shown by way of example. That is, the shapes of the spherical or aspherical surfaces are not limited to the shapes of the spherical or aspherical surfaces shown in the drawings. The drawings are only examples and are not drawn strictly to scale.

[0047] In this article, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the convex position is not defined, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the concave position is not defined, it means that the lens surface is concave at least in the paraxial region.

[0048] It should also be understood that the terms "comprises", "including", "having", "includes" and / or "comprising", when used in this specification, indicate the presence of the stated features, elements and / or components, but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof. In addition, when expressions such as "at least one of..." appear after a list of listed features, they modify the entire listed features rather than modifying the individual elements in the list. In addition, when describing embodiments of the present application, "may" is used to mean "one or more embodiments of the present application". And, the term "exemplary" is intended to refer to an example or illustration.

[0049] Unless otherwise defined, all terms (including technical terms and scientific terms) used in this article have the same meaning as commonly understood by ordinary technicians in the field to which this application belongs. It should also be understood that terms (such as terms defined in commonly used dictionaries) should be interpreted as having the same meaning as their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless explicitly defined in this article.

[0050] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0051] The present invention provides an optical lens, which is used to modulate the light signal emitted by the image source and transmit it to the entrance pupil side of the human eye. The optical lens is arranged in the light emitting direction of the image source, that is, the emitting surface of the image source is the light emitting side of the light signal. The optical lens is composed of seven lenses, and includes: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens and a seventh lens in sequence from the entrance pupil side of the human eye to the image source side in the opposite direction of light transmission; the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens each include a light entrance surface close to the image source side and a light exit surface close to the entrance pupil side of the human eye. It can be understood that the surface of each lens close to the image source is called the light entrance surface of the lens, and the surface of each lens close to the entrance pupil side of the human eye is called the light exit surface of the lens. It should be noted that the entrance pupil position of the human eye is the aperture of the optical lens.

[0052] In some embodiments, the first lens may have positive focal power, the light exit surface of the first lens is a convex surface or a plane, and the light incident surface of the first lens is a convex surface. The second lens may have positive focal power or negative focal power, the light exit surface of the second lens is a convex surface, and the light incident surface of the second lens is a convex surface or a concave surface. The third lens may have positive focal power, the light exit surface of the third lens is a convex surface, and the light incident surface of the third lens is a convex surface. The fourth lens may have negative focal power, the light exit surface of the fourth lens is a concave surface or a convex surface, and the light incident surface of the fourth lens is a concave surface. The fifth lens may have positive focal power, the light exit surface of the fifth lens is a convex surface, and the light incident surface of the fifth lens is a concave surface or a convex surface. The sixth lens may have negative focal power, the light exit surface of the sixth lens is a concave surface or a convex surface, and the light incident surface of the sixth lens is a concave surface. The seventh lens may have positive focal power or negative focal power, the light exit surface of the seventh lens is a convex surface, and the light incident surface of the seventh lens is a concave surface.

[0053] In order to meet the wearing needs of users with different refractive degrees, the air spacing CT between the entire lens group (composed of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens) and the image source on the optical axis can be dynamically adjusted. W (i.e., the distance between the light incident surface of the seventh lens and the image source on the optical axis) to achieve the adjustment of the optical lens between different refractive powers, so as to well meet the wearing needs of users with different refractive powers. More specifically, the distance CT between the light incident surface of the seventh lens and the image source side on the optical axis is W The adjustment range meets: 5mm <CT W< 15 mm. Meeting the above conditions can endow the lens with a relatively large optical back focal length. On the one hand, it can provide a relatively large refraction space for the light rays emitted from the image source side, improving the adaptability of the optical lens to a large-size display screen. At the same time, a relatively large space is reserved between the image source and the optical lens, facilitating the adjustment of the distance between the two, so that diopter adjustment within a relatively large range (such as -7D to +2D) can be achieved, meeting the wearing needs of users with different myopia or hyperopia degrees. Moreover, the diopter adjustment method of this application is simple and can be achieved only by moving the screen.

[0054] In some embodiments, the length IH of the display area of the image source that the optical lens can match and the effective focal length f of the optical lens satisfy: 1.2 < IH / f < 1.3. Meeting the above conditions can enable the optical lens to match a large-size image source (display screen) to achieve high-definition imaging, bringing an excellent sensory experience to users. At the same time, it is beneficial to realize the long-focus performance of the lens, better present larger local details, make the picture more concentrated and compact, thus meeting the visual experience of the human eye.

[0055] In some embodiments, the exit pupil distance ED of the optical lens and the effective focal length f of the optical lens satisfy: 0.42 < ED / f < 0.47. The exit pupil distance ED represents the distance on the optical axis from the entrance pupil side of the human eye to the light-emitting surface of the first lens. Meeting the above conditions can ensure a relatively large entrance pupil distance while achieving a relatively large field of view angle, reducing the dizziness feeling when the human eye wears it and improving the sensory experience.

[0056] In some embodiments, the sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis respectively and the sum ∑AT of the distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 5 < ∑CT / ∑AT < 10. Meeting the above conditions is beneficial to the smooth transition of light rays, and at the same time corrects various aberrations of the optical lens, improving the imaging quality of the optical lens.

[0057] In some embodiments, the effective focal length f of the optical lens and the combined focal length f12 of the first lens and the second lens satisfy: 0.8 < f12 / f < 4. Meeting the above conditions is beneficial to the smooth transition of light rays, and at the same time corrects various aberrations of the optical lens, improving the imaging quality of the optical lens.

[0058] In some embodiments, the effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 1 < f1 / f < 3; the curvature radius R2 of the incident light surface of the first lens and the effective focal length f of the optical lens satisfy: -5 < R2 / f < -0.5. Meeting the above conditions can effectively converge the light rays, making the outgoing light enter the human eye observation area at a relatively parallel angle of view, providing a better immersion experience for users while ensuring a relatively large eye movement range of the system.

[0059] In some embodiments, the second lens may have an appropriate positive optical power, and the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 2 < f2 / f < 5; the radius of curvature R3 of the light-emitting surface of the second lens and the effective focal length f of the optical lens satisfy: 1 < R3 / f < 4. Meeting the above conditions can further converge the light rays, enable the light rays to enter the system at a relatively gentle angle of view, reduce the difficulty of correcting aberrations and distortions, and improve the overall imaging quality.

[0060] In some embodiments, the effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.5 < f3 / f < 4.5; the radius of curvature R5 of the light-emitting surface of the third lens and the radius of curvature R6 of the light-incident surface of the third lens satisfy: -0.35 < R5 / R6 < -0.01. Meeting the above conditions is beneficial to converging the light rays emitted from the image source side, reducing the divergence degree of the light rays, and thus entering the human eye at an angle of view close to parallel, ensuring a large field of view angle while improving the overall imaging quality.

[0061] In some embodiments, the effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -4 < f4 / f < -0.5; the radius of curvature R8 of the light-incident surface of the fourth lens and the effective focal length f of the optical lens satisfy: 0.3 < R8 / f < 7. Meeting the above conditions can appropriately slow down the turning degree of the light rays, diverge the light rays better into the human eye, and thus can provide a wide field of view display effect and improve the user's immersion.

[0062] In some embodiments, the effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 2.5; the radius of curvature R9 of the light-emitting surface of the fifth lens and the effective focal length f of the optical lens satisfy: 0.4 < R9 / f < 6. Meeting the above conditions is beneficial to the convergence of the light rays, enables the light rays emitted from the image source side to smoothly enter the rear optical system, reduces the difficulty of correcting various aberrations, and better realizes the high-quality imaging of the lens.

[0063] In some embodiments, the effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -5 < f6 / f < -0.3. Meeting the above conditions can greatly diverge the light rays emitted from the image source side to increase the area of the projected virtual image and provide a better immersion experience for the user.

[0064] In some embodiments, the total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.29 < TTL / f < 1.4; the total optical length TTL of the optical lens and the display area length IH of the image source that the optical lens can match satisfy: 1 < TTL / IH < 1.2. Meeting the above conditions can enable the lens to have a relatively compact system, while also having a large image plane, being able to match a larger-sized image source (display screen) to achieve high-definition imaging, and bringing an excellent sensory experience to users.

[0065] In some embodiments, the curvature radius R13 of the light-emitting surface of the seventh lens and the curvature radius R14 of the light-incident surface of the seventh lens satisfy: 0.5 < R13 / R14 < 2. Meeting the above conditions, by reasonably setting the meniscus shape of the seventh lens, the light emitted from a large-sized image source (display screen) can be received to a greater extent, improving the matching degree between the lens and the large-sized display screen.

[0066] In some embodiments, the focal length f3 of the third lens and the focal length f4 of the fourth lens satisfy: -7 < f3 / f4 < -0.5. Meeting the above conditions is beneficial to correcting the aberration and distortion of the edge field of view and improving the imaging quality of the optical lens.

[0067] In some embodiments, the focal length f5 of the fifth lens and the focal length f6 of the sixth lens satisfy: -3 < f5 / f6 < -0.1. Meeting the above conditions is beneficial to the smooth transition of light, while correcting various aberrations of the optical lens and improving the imaging quality of the optical lens.

[0068] In some embodiments, the effective aperture DM11 of the light-emitting surface of the first lens and the effective aperture DM72 of the light-incident surface of the seventh lens satisfy: 0.6 < DM11 / DM72 < 0.7. Meeting the above conditions, by reasonably setting the aperture relationship between the first and last lenses, the light emitted from the display screen can enter the human eye observation area at a relatively parallel and wide viewing angle, ensuring a large eye movement range of the system while providing a better immersive experience for users.

[0069] In some embodiments, the optical lens satisfies the conditional formula: 27mm < f < 28mm; 60° < FOV < 70°, 33.5mm < IH < 34.5mm; where TTL represents the total optical length of the optical lens, f represents the effective focal length of the optical lens, FOV represents the maximum field of view angle of the optical lens, and IH represents the display area length of the image source that the optical lens can match. Meeting the above conditions indicates that the optical lens provided by the embodiments of the present invention has the advantages of long focal length characteristics, a large field of view angle, and being able to match a larger-sized (1.33 inches) display screen to achieve the viewing effect of a giant screen image.

[0070] In some embodiments, the lens material in the optical lens provided by the present invention can be glass or plastic. When the lens material is plastic, the production cost can be effectively reduced. When the lens material is glass, the geometric chromatic aberration of the optical lens can be effectively corrected by the low dispersion characteristic of the glass itself. The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens are all plastic lenses.

[0071] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens may be spherical lenses or aspherical lenses. Compared with spherical structures, aspherical structures can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and reducing the size of lenses, and better realizing miniaturization of lenses. More specifically, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens of the present invention may all be aspherical lenses, which can effectively reduce the aberration of the optical lens, thereby reducing the number of lenses and reducing the size of lenses, and better realizing miniaturization of lenses.

[0072] In various embodiments of the present invention, when the lens is an aspherical lens, the shapes of the aspherical surfaces of the optical lens satisfy the following equations:

[0073] ;

[0074] Among them, z is the distance between the surface and the vertex of the surface in the direction of the optical axis, h is the distance from the optical axis to the surface, c is the curvature of the surface vertex, K is the quadratic surface coefficient, B, C, D, E, F, G, and H are the fourth-order, sixth-order, eighth-order, tenth-order, twelfth-order, fourteenth-order, and sixteenth-order surface coefficients respectively.

[0075] In addition, the present invention also provides a near-eye display device, which includes, in sequence along the direction of light signal transmission: an image source, the above-mentioned optical lens; the image source is used to emit a light signal, and the light signal includes image information; the optical lens is arranged in the light emitting direction of the image source, and the seventh lens is arranged closer to the image source than the first lens, and the optical lens is used to modulate the light signal emitted by the image source and transmit it to the human eye.

[0076] The present invention is further described below in multiple embodiments. In each embodiment, the thickness, radius of curvature, and material selection of each lens in the optical lens are different. For specific differences, please refer to the parameter table of each embodiment. The following embodiments are only preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the following embodiments. Any other changes, substitutions, combinations or simplifications that do not deviate from the innovative points of the present invention should be regarded as equivalent replacement methods and are included in the protection scope of the present invention.

[0077] Example 1

[0078] See also Figure 1 , which is a schematic diagram of the structure of a near-eye display device 500 provided in an embodiment of the present invention, please refer to Figure 2 , which is a schematic diagram of the structure of the optical lens 100 provided in Embodiment 1 of the present invention, is used to modulate the optical signal emitted by the image source 10 and transmit it to the entrance pupil side of the human eye. The optical lens 100 is arranged in the light emitting direction of the image source 10, that is, the emitting surface of the image source 10 is the light emitting side of the optical signal. Figure 2 It can be seen that the optical lens 100 is sequentially provided with the following components along the reverse direction of light transmission (i.e., from the entrance pupil side of the human eye to the image source side): an aperture ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, and a seventh lens L7. The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7 each include a light entrance surface close to the image source side and a light exit surface close to the entrance pupil side of the human eye. It can be understood that the surface of each lens close to the image source 10 is called the light entrance surface of the lens, and the surface of each lens close to the entrance pupil side of the human eye is called the light exit surface of the lens. It should be noted that the entrance pupil position of the human eye is the aperture ST of the optical lens 100.

[0079] The first lens L1 has positive refractive power, a light exiting surface S1 of the first lens is a convex surface, and a light incident surface S2 of the first lens is a convex surface;

[0080] The second lens L2 has positive refractive power, a light exiting surface S3 of the second lens is a convex surface, and a light incident surface S4 of the second lens is a convex surface;

[0081] The third lens L3 has positive refractive power, a light exiting surface S5 of the third lens is a convex surface, and a light incident surface S6 of the third lens is a convex surface;

[0082] The fourth lens L4 has negative optical power, a light exiting surface S7 of the fourth lens is a convex surface, and a light incident surface S8 of the fourth lens is a concave surface;

[0083] The fifth lens L5 has positive refractive power, a light exiting surface S9 of the fifth lens L5 is a convex surface, and a light incident surface S10 of the fifth lens L5 is a concave surface at the near optical axis;

[0084] The sixth lens L6 has negative refractive power, a light exiting surface S11 of the sixth lens L6 is a concave surface, and a light incident surface S12 of the sixth lens L6 is a concave surface;

[0085] The seventh lens L7 has positive refractive power. The light-emitting surface S13 of the seventh lens L7 is a convex surface, and the light-incident surface S14 of the seventh lens L7 is a concave surface.

[0086] The first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6 and the seventh lens L7 are all plastic aspherical lenses.

[0087] In order to meet the wearing needs of users with different refractive degrees, the air spacing CT between the entire lens group (composed of the first lens L1, the second lens L2, the third lens L3, the fourth lens L4, the fifth lens L5, the sixth lens L6, and the seventh lens L7) and the image source 10 on the optical axis can be dynamically adjusted. W (The distance between the light incident surface of the seventh lens L7 and the image source 10 on the optical axis) is used to realize the adjustment of the optical lens between different refractive powers, thereby being able to well meet the wearing needs of users with different refractive powers.

[0088] Specifically, in this embodiment, the distance CT between the light incident surface of the seventh lens and the image source side on the optical axis is W The adjustment range is 7.718~14.011mm, which can achieve -700~200 degrees (-7D~2D) of diopter adjustment, so that users with different degrees of myopia or hyperopia can have a good sensory experience when wearing it. Figure 2 , which is a schematic diagram of the structure of the optical lens 100 when the diopter is 0D (0°). W is 12.383mm; when CT W When the CT W When the angle of the optical lens 100 is 14.011 mm, the diopter of the optical lens 100 is 2D (200°). In this embodiment, the diopter can be adjusted by moving the screen.

[0089] The relevant parameters of each lens in the optical lens 100 in Example 1 are shown in Table 1-1.

[0090] Table 1-1

[0091]

[0092] The surface parameters of the aspheric lens of the optical lens 100 in Example 1 are shown in Table 1-2.

[0093] Table 1-2

[0094]

[0095] Please refer to Figure 3, which is a field curvature curve of the optical lens 100, indicating the degree of curvature of light in the meridian image plane and the sagittal image plane, the horizontal axis indicates the offset (unit: mm), and the vertical axis indicates the field angle (unit: °). It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.7mm, indicating that the optical lens 100 can correct the field curvature well.

[0096] Please refer to Figure 4 , which is a F-Tan(θ) distortion curve of the optical lens 100, wherein the horizontal axis represents the F-Tan(θ) distortion percentage, and the vertical axis represents the field of view angle (unit: degree). Figure 4 It can be seen that the F-Tan (θ) distortion value at the image height received by the user's eyes is controlled within ±3%, indicating that the distortion of the optical lens 100 is well corrected.

[0097] from Figure 3 , Figure 4 It can be seen that the aberration of the optical lens 100 is well balanced and has good imaging quality.

[0098] Example 2

[0099] See also Figure 5 , which is a schematic diagram of the structure of the optical lens 200 provided in Example 2 of the present invention. Compared with Example 1, the main differences of this embodiment are: the second lens L2 has negative optical power; the seventh lens L7 has negative optical power; the light incident surface S4 of the second lens L2 is a concave surface; the light emitting surface S7 of the fourth lens L4 is a concave surface; the light incident surface S10 of the fifth lens L5 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0100] In this embodiment, the distance CT between the light incident surface of the seventh lens and the image source side on the optical axis is W The adjustment range is 8.008~14.458mm. Figure 5 , which is a schematic diagram of the structure of the optical lens 200 when the diopter is 0D (0°). W is 12.792mm; when CT W When the CT W When the diameter of the optical lens 200 is 14.458 mm, the refractive power of the optical lens 200 is 2D (200°).

[0101] The relevant parameters of each lens in the optical lens 200 in Example 2 are shown in Table 2-1.

[0102] Table 2-1

[0103]

[0104] The surface parameters of the aspheric lens of the optical lens 200 in Example 2 are shown in Table 2-2.

[0105] Table 2-2

[0106]

[0107] Please refer to Figure 6 , which is a field curvature curve of the optical lens 200, indicating the degree of curvature of light in the meridian image plane and the sagittal image plane, the horizontal axis indicates the offset (unit: mm), and the vertical axis indicates the field angle (unit: °). It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.6mm, indicating that the optical lens 200 can correct the field curvature well.

[0108] Please refer to Figure 7 , which is a F-Tan(θ) distortion curve of the optical lens 200, wherein the horizontal axis represents the F-Tan(θ) distortion percentage, and the vertical axis represents the field of view angle (unit: degree). Figure 7 It can be seen that the F-Tan (θ) distortion value at the image height received by the user's eyes is controlled within ±4%, indicating that the distortion of the optical lens 200 is well corrected.

[0109] from Figure 6 , Figure 7 It can be seen that the aberration of the optical lens 200 is well balanced and has good imaging quality.

[0110] Example 3

[0111] See also Figure 8 , which is a schematic diagram of the structure of the optical lens 300 provided in Example 3 of the present invention. Compared with Example 1, this embodiment mainly differs in that: the seventh lens L7 has negative optical power; the light-emitting surface S1 of the first lens L1 is a plane; the light-emitting surface S7 of the fourth lens L4 is a concave surface; the light-incident surface S10 of the fifth lens L5 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0112] In this embodiment, the distance CT between the light incident surface of the seventh lens and the image source side on the optical axis is W The adjustment range is 5.496~10.732mm. Figure 8 , which is a schematic diagram of the structure of the optical lens 300 when the diopter is 0D (0°). W is 9.604mm; when CT W When the CT W When the angular width of the optical lens 300 is 10.732 mm, the refractive power of the optical lens 300 is 2D (200°).

[0113] The relevant parameters of each lens in the optical lens 300 in Example 3 are shown in Table 3-1.

[0114] Table 3-1

[0115]

[0116] The surface parameters of the aspheric lens of the optical lens 300 in Example 3 are shown in Table 3-2.

[0117] Table 3-2

[0118]

[0119] Please refer to Fig. 9 , which is a field curvature curve of the optical lens 300, indicating the degree of curvature of light in the meridian image plane and the sagittal image plane, the horizontal axis indicates the offset (unit: mm), and the vertical axis indicates the field angle (unit: °). It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.4mm, indicating that the optical lens 300 can correct the field curvature well.

[0120] Please refer to Fig.10 , which is a F-Tan(θ) distortion curve of the optical lens 300, wherein the horizontal axis represents the F-Tan(θ) distortion percentage, and the vertical axis represents the field of view angle (unit: degree). Fig.10 It can be seen that the F-Tan (θ) distortion value at the image height received by the user's eyes is controlled within ±4%, indicating that the distortion of the optical lens 300 is well corrected.

[0121] from Fig. 9 , Fig.10 It can be seen that the aberration of the optical lens 300 is well balanced and has good imaging quality.

[0122] Example 4

[0123] See also Fig.11 , which is a schematic diagram of the structure of an optical lens 400 provided in Example 4 of the present invention. Compared with Example 1, this embodiment mainly differs in that: the light-emitting surface S7 of the fourth lens L4 is a concave surface; the light-incident surface S11 of the sixth lens L6 is a convex surface; and the optical parameters such as the curvature radius of each lens surface and the lens thickness are different.

[0124] In this embodiment, the distance CT between the light incident surface of the seventh lens and the image source side on the optical axis is W The adjustment range is 5.115~11.304mm. Fig.11 , which is a schematic diagram of the structure of the optical lens 400 when the diopter is 0D (0°). Wis 9.683mm; when CT W When the CT W When the diameter of the optical lens 400 is 11.304 mm, the refractive power of the optical lens 400 is 2D (200°).

[0125] The relevant parameters of each lens in the optical lens 400 in Example 4 are shown in Table 4-1.

[0126] Table 4-1

[0127]

[0128] The surface parameters of the aspheric lens of the optical lens 400 of Example 4 are shown in Table 4-2.

[0129] Table 4-2

[0130]

[0131] Please refer to Fig.12 , which is a field curvature curve of the optical lens 400, indicating the degree of curvature of light in the meridian image plane and the sagittal image plane, the horizontal axis indicates the offset (unit: mm), and the vertical axis indicates the field angle (unit: °). It can be seen from the figure that the field curvature of the meridian image plane and the sagittal image plane is controlled within ±0.6mm, indicating that the optical lens 400 can correct the field curvature well.

[0132] Please refer to Fig.13 , which is a F-Tan(θ) distortion curve of the optical lens 400, wherein the horizontal axis represents the F-Tan(θ) distortion percentage, and the vertical axis represents the field of view angle (unit: degree). Fig.13 It can be seen that the F-Tan (θ) distortion value at the image height received by the user's eyes is controlled within ±3%, indicating that the distortion of the optical lens 400 is well corrected.

[0133] from Fig.12 , Fig.13 It can be seen that the aberration of the optical lens 400 is well balanced and has good imaging quality.

[0134] Please refer to Table 5, which shows the optical characteristics of the optical lenses provided in the above four embodiments when the diopter is 0D (0°), including the effective focal length f, total optical length TTL, aperture value Fno, maximum field of view FOV, entrance pupil diameter EPD, exit pupil distance ED, and display area length IH of the image source that the optical lens can match, and the numerical value corresponding to each conditional expression in each embodiment.

[0135] Table 5

[0136]

[0137] In summary, the optical lens provided by the present invention has at least the following advantages:

[0138] (1) Through specific surface shape settings and reasonable optical focal length distribution, the optical lens has a larger field of view angle. The larger field of view angle can provide a wide field of view display effect, giving users a better experience. At the same time, the optical lens has the characteristics of low distortion, which improves the imaging quality.

[0139] (2) The optical lens also has a larger image surface and higher resolution, which can be matched with a larger size (1.33 inches) display to achieve a giant screen image effect, bringing users an excellent sensory experience.

[0140] (3) Different diopter adjustments can be achieved by adjusting the spatial distance between the lens group and the image source on the optical axis. A wide range of diopter adjustments (-7D to +2D) can be achieved, and all have high imaging quality, which can meet the needs of different myopic users. At the same time, it has a large exit pupil distance, which can provide users with a better experience.

[0141] Example 5

[0142] See also Fig.14 , which is a schematic diagram of an optical path in a near-eye display device 500 provided by an embodiment of the present invention, the near-eye display device 500 includes an image source 10, an optical lens (such as optical lens 100) in any of the aforementioned embodiments of the present application, and the optical lens 100 is located between the human eye 20 and the image source 10. The image information emitted from the image source 10 enters the human eye 20 through the optical lens 100 to form an image, and a high-definition magnified virtual image can be observed in the human eye 20, which has an extremely realistic sensory experience.

[0143] The image source 10 is used to emit a light signal, and the light signal includes image information. Specifically, the image source 10 can be one of a display screen such as Micro LED, OLED, LCD, LCOS, M-OLED, etc., and can provide high-definition image information for the optical lens 100.

[0144] The optical lens 100 is arranged in the light emitting direction of the image source 10 , and the seventh lens in the optical lens 100 is arranged closer to the image source 10 than the first lens. The optical lens 100 is used to modulate the light signal emitted by the image source 10 and transmit it to the human eye 20 .

[0145] The near-eye display device 500 can be VR glasses, VR helmets, head-mounted display devices, etc. By adjusting the distance between the lens and the image source side, the diopter can be adjusted (-7D~2D), so that users with different degrees of myopia or hyperopia can have a better wearing experience. Since the above-mentioned optical lens has a large field of view, the large field of view can provide a wide field of view display effect, improve the user's sense of immersion, and thus bring a better experience to the user. At the same time, the optical lens also has a large image surface and a high resolution. The light signal image modulated by the optical lens is bright and clear, the effect is better, and the picture projected to the human eye is clearer. Therefore, the near-eye display device equipped with the optical lens has at least the characteristics of a wide field of view and high image quality, which can effectively improve the user's visual experience and comfort.

[0146] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0147] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An optical lens, consisting of seven lenses, characterized in that: Along the reverse direction of light transmission, from the side of the entrance pupil of the human eye to the side of the image source, it successively includes: a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens; each of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, and the seventh lens includes an incident light surface close to the side of the image source and an emergent light surface close to the side of the entrance pupil of the human eye; The first lens has a positive focal power, the emergent light surface of the first lens is a convex surface or a flat surface, and the incident light surface of the first lens is a convex surface; The second lens has a focal power, and the emergent light surface of the second lens is a convex surface; The third lens has a positive focal power, the emergent light surface of the third lens is a convex surface, and the incident light surface of the third lens is a convex surface; The fourth lens has a negative focal power, and the incident light surface of the fourth lens is a concave surface; The fifth lens has a positive focal power, and the emergent light surface of the fifth lens is a convex surface; The sixth lens has a negative focal power, and the incident light surface of the sixth lens is a concave surface; The seventh lens has a focal power, the emergent light surface of the seventh lens is a convex surface, and the incident light surface of the seventh lens is a concave surface; The distance CT between the light incident surface of the seventh lens and the image source on the optical axis W The range is adjustable; Wherein, the length IH of the display area of the image source that the optical lens can match and the effective focal length f of the optical lens satisfy: 1.2 < IH / f < 1.3; The exit pupil distance ED of the optical lens and the effective focal length f of the optical lens satisfy: 0.42 < ED / f < 0.

47.

2. The optical lens according to claim 1, characterized in that: The sum ∑CT of the central thicknesses of the first lens to the seventh lens along the optical axis respectively and the sum ∑AT of the distances between any two adjacent lenses of the first lens to the seventh lens on the optical axis satisfy: 5 < ∑CT / ∑AT < 10.

3. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the combined focal length f12 of the first lens and the second lens satisfy: 0.8 < f12 / f < 4.

4. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f1 of the first lens satisfy: 1 < f1 / f < 3; the radius of curvature R2 of the incident light surface of the first lens and the effective focal length f of the optical lens satisfy: -5 < R2 / f < -0.

5.

5. The optical lens according to claim 1, characterized in that: The second lens has a positive focal power, and the effective focal length f of the optical lens and the focal length f2 of the second lens satisfy: 2 < f2 / f < 5.

6. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f3 of the third lens satisfy: 1.5 < f3 / f < 4.5; the radius of curvature R5 of the emergent light surface of the third lens and the radius of curvature R6 of the incident light surface of the third lens satisfy: -0.35 < R5 / R6 < -0.

01.

7. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f4 of the fourth lens satisfy: -4 < f4 / f < -0.

5.

8. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f5 of the fifth lens satisfy: 0.5 < f5 / f < 2.

5.

9. The optical lens according to claim 1, characterized in that: The effective focal length f of the optical lens and the focal length f6 of the sixth lens satisfy: -5 < f6 / f < -0.

3.

10. The optical lens according to claim 1, characterized in that: The total optical length TTL of the optical lens and the effective focal length f of the optical lens satisfy: 1.29 < TTL / f < 1.4; the total optical length TTL of the optical lens and the length IH of the display area of the image source that the optical lens can match satisfy: 1 < TTL / IH < 1.

2.

11. A near-eye display device, characterized in that: In the light signal transmission direction, it successively includes: an image source, and the optical lens according to any one of claims 1-10; The image source is used for emitting a light signal, and the light signal includes image information; The optical lens is disposed in the light-emitting direction of the image source, and the seventh lens is disposed closer to the image source than the first lens. The optical lens is used for modulating the light signal emitted by the image source and transmitting it to the human eye.

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