Optical lens

Abstract

The present application discloses an optical lens, which comprises, in order from the human eye side to the image source side along the optical axis: a first lens having optical power, whose side surface near the image source is convex; a second lens having negative optical power, whose side surface near the image source is concave; a third lens having positive optical power, whose side surface near the imaging surface is convex, and whose side surface near the image source is convex; a fourth lens having optical power, whose side surface near the imaging surface is convex; and a fifth lens having optical power, whose side surface near the image source is concave. The optical lens satisfies the following conditions: 0.3<(CT4+T45+CT5) / Tr1r6<0.7 and ‑1.3<R6 / f<‑0.9, where Tr1r6 is the distance on the optical axis from the near imaging side of the first lens element to the near image source side of the third lens element, CT4 is the center thickness of the fourth lens element, T45 is the distance on the optical axis from the near image source side of the fourth lens element to the near imaging side of the fifth lens element, CT5 is the center thickness of the fifth lens element, R6 is the radius of curvature of the near image source side of the third lens element, and f is the total effective focal length of the optical lens.

Description

Technical Field

[0001] The present application relates to the field of optical elements, and in particular, to an optical lens. Background Art

[0002] Virtual reality (VR) technology is a computer-generated, interactive, and immersive visual virtual environment. It can generate a variety of virtual environments on demand and is widely used in fields such as urban planning, driver training, and interior design. In recent years, with the advancement of computing power and various types of sensors, various types of VR helmets have appeared on the market. They basically consist of a display screen or mobile phone and a pair of display eyepieces (i.e., optical lenses). The human eye sees a magnified image on the screen located on the image source side through the display eyepieces. Sensors detect movements in the human head and adjust the images on the left and right screens, allowing the human eye to perceive a three-dimensional, interactive visual image.

[0003] With the rapid development of virtual reality technology, the display eyepiece (i.e., optical lens, such as a projection lens) is a core optical component of VR headsets. Its image quality, weight, size, and other key indicators are directly related to the user experience and comfort when wearing the VR headset. Although the eyepieces currently used in VR headsets offer a better sense of immersion due to their simple lens configuration, resulting in a short focal length, a large viewing range, and a compact device, this can also lead to problems such as increased blur and dispersion at the edges of the image, as well as severe image distortion.

[0004] Therefore, how to design an optical lens that can be installed in portable electronic devices such as VR headsets and still have good imaging quality while being small in size and light in weight has become one of the difficult problems that many lens designers urgently need to solve. Summary of the Invention

[0005] The present application provides an optical lens, which includes, in order from the human eye side to the image source side along the optical axis: a first lens having optical power, whose side surface near the image source is convex; a second lens having negative optical power, whose side surface near the image source is concave; a third lens having positive optical power, whose side surface near the imaging direction is convex, and whose side surface near the image source is convex; a fourth lens having optical power, whose side surface near the imaging direction is convex; and a fifth lens having optical power, whose side surface near the image source is concave. The optical lens may satisfy: 0.3<(CT4+T45+CT5) / Tr1r6<0.7 and -1.3<R6 / f<-0.9, wherein Tr1r6 is the distance on the optical axis from the near imaging side of the first lens to the near image source side of the third lens, CT4 is the center thickness of the fourth lens, T45 is the distance on the optical axis from the near image source side of the fourth lens to the near imaging side of the fifth lens, CT5 is the center thickness of the fifth lens, R6 is the curvature radius of the near image source side of the third lens, and f is the total effective focal length of the optical lens.

[0006] In one embodiment, at least one of the mirror surfaces from the near imaging side surface of the first lens to the near image source side surface of the fifth lens is an aspherical mirror surface.

[0007] In one embodiment, the optical lens may satisfy: ET3 / ET2<0.5, where ET3 is the edge thickness of the third lens at the maximum effective radius, and ET2 is the edge thickness of the second lens at the maximum effective radius.

[0008] In one embodiment, the optical lens may satisfy: 1.2<(CT4+CT5) / (ET4+ET5)<2.0, wherein CT4 is the center thickness of the fourth lens, CT5 is the center thickness of the fifth lens, ET4 is the edge thickness of the fourth lens at the maximum effective radius, and ET5 is the edge thickness of the fifth lens at the maximum effective radius.

[0009] In one embodiment, the optical lens may satisfy: 1<DT32 / DT41<1.5, wherein DT32 is the maximum effective radius of the side near the image source of the third lens, and DT41 is the maximum effective radius of the side near the image formation of the fourth lens.

[0010] In one embodiment, the optical lens may satisfy: 0.8<DT12 / DT21<1.1, wherein DT12 is the maximum effective radius of the near image source side of the first lens, and DT21 is the maximum effective radius of the near image side of the second lens.

[0011] In one embodiment, the optical lens may satisfy: -1.1<SAG32 / SAG41<-0.7, wherein SAG32 is the distance from the intersection of the near image source side of the third lens and the optical axis to the vertex of the effective radius of the near image source side of the third lens on the optical axis, and SAG41 is the distance from the intersection of the near imaging side of the fourth lens and the optical axis to the vertex of the effective radius of the near imaging side of the fourth lens on the optical axis.

[0012] In one embodiment, the optical lens may satisfy the following condition: 0.6<(DT32-DT41) / (DT41-DT52)<1.3, where DT32 is the maximum effective radius of the near image source side of the third lens, DT41 is the maximum effective radius of the near imaging side of the fourth lens, and DT52 is the maximum effective radius of the near image source side of the fifth lens.

[0013] In one embodiment, the optical lens may satisfy: 2< SAG21 / CT2 + SAG22 / CT2 <5.5, where SAG21 is the distance from the intersection of the near imaging side surface of the second lens and the optical axis to the vertex of the effective radius of the near imaging side surface of the second lens on the optical axis, SAG22 is the distance from the intersection of the near image source side surface of the second lens and the optical axis to the vertex of the effective radius of the near image source side surface of the second lens on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

[0014] In one embodiment, the optical lens may satisfy the following condition: 0.6<(T12+T23) / ∑AT<1, where T12 is the distance on the optical axis from the near image source side of the first lens to the near imaging side of the second lens, T23 is the distance on the optical axis from the near image source side of the second lens to the near imaging side of the third lens, and ∑AT is the sum of the air spaces on the optical axis between any two adjacent lenses from the first lens to the fifth lens.

[0015] In one embodiment, the optical lens may satisfy: -1<f2 / f1<-0.3, where f2 is the effective focal length of the second lens, and f1 is the effective focal length of the first lens.

[0016] In one embodiment, the optical lens may satisfy the following condition: 0.4<DTmax / TD<0.7, where DTmax is the maximum value of the maximum effective radius from the near imaging side surface of the first lens to the near image source side surface of the fifth lens, and TD is the distance from the near imaging side surface of the first lens to the near image source side surface of the fifth lens on the optical axis.

[0017] In one embodiment, the optical lens may satisfy: 3<TD / ImgH<4.5, where TD is the distance on the optical axis from the near imaging side of the first lens to the near image source side of the fifth lens, and ImgH is half the diagonal length of the image source surface of the optical lens.

[0018] In one embodiment, the optical lens may satisfy: 0.6<∑ET / ∑CT<1, where ∑ET is the sum of the edge thicknesses of the first lens to the fifth lens at the maximum effective diameter, and ∑CT is the sum of the center thicknesses of the first lens to the fifth lens on the optical axis.

[0019] In one embodiment, the optical lens may satisfy: tan(FOV / 2)×f / EPD<1, where FOV is the maximum field of view of the optical lens, EPD is the entrance pupil diameter of the optical lens, and f is the total effective focal length of the optical lens.

[0020] In one embodiment, the optical lens may satisfy: 1<f123 / f<2, where f123 is the combined focal length of the first lens, the second lens, and the third lens, and f is the total effective focal length of the optical lens.

[0021] Another aspect of the present application provides an optical lens. The optical lens comprises, in order from the human eye side to the image source side along the optical axis: a first lens group with positive optical power, comprising a first lens with optical power, a second lens, and a third lens; a second lens group with optical power, comprising a fourth lens with positive optical power and a fifth lens with optical power. The optical power of the first lens 1 and the optical power of the second lens 2 can satisfy: 1× 2<0; the near imaging side surface of at least one of the first lens, the second lens, and the third lens is convex, and the near image source side surface is convex; the near image source side surface of the fifth lens is concave; and the optical lens can satisfy: f×tan(FOV / 4)<6 mm, where f is the total effective focal length of the optical lens, and FOV is the maximum field of view of the optical lens.

[0022] In one embodiment, the optical lens may satisfy: 0<(N1max-N1_2) / N1_2<0.5, wherein N1max is the maximum refractive index of the first to third lenses, and N1_2 is the refractive index of the second lens.

[0023] The optical lens satisfies: ET3 / ET2<0.5, wherein ET3 is the edge thickness of the third lens at the maximum effective radius, and ET2 is the edge thickness of the second lens at the maximum effective radius.

[0024] In one embodiment, the optical lens may satisfy: 1.2<(CT4+CT5) / (ET4+ET5)<2.0, wherein CT4 is the center thickness of the fourth lens, CT5 is the center thickness of the fifth lens, ET4 is the edge thickness of the fourth lens at the maximum effective radius, and ET5 is the edge thickness of the fifth lens at the maximum effective radius.

[0025] In one embodiment, the optical lens may satisfy: 1<DT32 / DT41<1.5, wherein DT32 is the maximum effective radius of the side near the image source of the third lens, and DT41 is the maximum effective radius of the side near the image formation of the fourth lens.

[0026] In one embodiment, the optical lens may satisfy: 0.8<DT12 / DT21<1.1, wherein DT12 is the maximum effective radius of the near image source side of the first lens, and DT21 is the maximum effective radius of the near image side of the second lens.

[0027] In one embodiment, the optical lens may satisfy: -1.1<SAG32 / SAG41<-0.7, wherein SAG32 is the distance from the intersection of the near image source side of the third lens and the optical axis to the vertex of the effective radius of the near image source side of the third lens on the optical axis, and SAG41 is the distance from the intersection of the near imaging side of the fourth lens and the optical axis to the vertex of the effective radius of the near imaging side of the fourth lens on the optical axis.

[0028] In one embodiment, the optical lens may satisfy the following condition: 0.6<(DT32-DT41) / (DT41-DT52)<1.3, where DT32 is the maximum effective radius of the near image source side of the third lens, DT41 is the maximum effective radius of the near imaging side of the fourth lens, and DT52 is the maximum effective radius of the near image source side of the fifth lens.

[0029] In one embodiment, the optical lens may satisfy: 2< SAG21 / CT2 + SAG22 / CT2 <5.5, where SAG21 is the distance from the intersection of the near imaging side surface of the second lens and the optical axis to the vertex of the effective radius of the near imaging side surface of the second lens on the optical axis, SAG22 is the distance from the intersection of the near image source side surface of the second lens and the optical axis to the vertex of the effective radius of the near image source side surface of the second lens on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

[0030] In one embodiment, the optical lens may satisfy the following condition: 0.6<(T12+T23) / ∑AT<1, where T12 is the distance on the optical axis from the near image source side of the first lens to the near imaging side of the second lens, T23 is the distance on the optical axis from the near image source side of the second lens to the near imaging side of the third lens, and ∑AT is the sum of the air spaces on the optical axis between any two adjacent lenses from the first lens to the fifth lens.

[0031] In one embodiment, the optical lens may satisfy: -1<f2 / f1<-0.3, where f2 is the effective focal length of the second lens, and f1 is the effective focal length of the first lens.

[0032] In one embodiment, the optical lens may satisfy the following condition: 0.4<DTmax / TD<0.7, where DTmax is the maximum value of the maximum effective radius from the near imaging side surface of the first lens to the near image source side surface of the fifth lens, and TD is the distance from the near imaging side surface of the first lens to the near image source side surface of the fifth lens on the optical axis.

[0033] In one embodiment, the optical lens may satisfy: 3<TD / ImgH<4.5, where TD is the distance on the optical axis from the near imaging side of the first lens to the near image source side of the fifth lens, and ImgH is half the diagonal length of the image source surface of the optical lens.

[0034] In one embodiment, the optical lens may satisfy: 0.6<∑ET / ∑CT<1, where ∑ET is the sum of the edge thicknesses of the first lens to the fifth lens at the maximum effective diameter, and ∑CT is the sum of the center thicknesses of the first lens to the fifth lens on the optical axis.

[0035] In one embodiment, the optical lens may satisfy: tan(FOV / 2)×f / EPD<1, where FOV is the maximum field of view of the optical lens, EPD is the entrance pupil diameter of the optical lens, and f is the total effective focal length of the optical lens.

[0036] In one embodiment, the optical lens may satisfy: 1<f123 / f<2, where f123 is the combined focal length of the first lens, the second lens, and the third lens, and f is the total effective focal length of the optical lens.

[0037] In one embodiment of the present application, by setting the near image source side of the first lens to be convex; setting the second lens to have negative optical power and the near image source side to be concave; setting the third lens to have positive optical power, and the near imaging side to be convex, and the near image source side to be convex; setting the near imaging side of the fourth lens to be convex; and setting the near image source side of the fifth lens to be concave, it is beneficial to improve the imaging quality of the optical lens and reduce the weight of the optical lens by reasonably setting the number of lenses, the optical power of the lenses and the surface shape. For example, by setting 0.3<Tr1r6 / (CT4+T45+CT5<0.7 and -1.3<R6 / f<-0.9, it is beneficial to achieve the compactness of the optical lens and to make the optical lens have the advantages of good imaging quality and small size at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Other features, objects and advantages of the present application will become more apparent upon reading the detailed description of non-limiting embodiments made with reference to the following drawings:

[0039] Figure 1 1 shows a schematic structural diagram of an optical lens according to Example 1 of the present application;

[0040] Figures 2A to 2D The axial chromatic aberration curve, astigmatism curve, distortion curve, and relative illumination curve of the optical lens of Example 1 are shown respectively;

[0041] Figure 3 1 shows a schematic structural diagram of an optical lens according to Example 2 of the present application;

[0042] Figures 4A to 4D The axial chromatic aberration curve, astigmatism curve, distortion curve, and relative illumination curve of the optical lens of Example 2 are respectively shown;

[0043] Figure 5 1 shows a schematic structural diagram of an optical lens according to Example 3 of the present application;

[0044] 6A to 6D The axial chromatic aberration curve, astigmatism curve, distortion curve, and relative illumination curve of the optical lens of Example 3 are shown respectively;

[0045] Figure 7 1 shows a schematic structural diagram of an optical lens according to Example 4 of the present application;

[0046] Figures 8A to 8D The axial chromatic aberration curve, astigmatism curve, distortion curve, and relative illumination curve of the optical lens of Example 4 are shown respectively;

[0047] Figure 9 shows a schematic structural diagram of an optical lens according to Example 5 of the present application; and

[0048] 10A to 10D The axial chromatic aberration curve, astigmatism curve, distortion curve and relative illumination curve of the optical lens of Example 5 are respectively shown. DETAILED DESCRIPTION

[0049] For a better understanding of the present application, various aspects of the present application will be described in more detail with reference to the accompanying drawings. It should be understood that these detailed descriptions are merely descriptions of exemplary 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.

[0050] It should be noted that in this specification, the terms "first," "second," "third," etc., are used solely to distinguish one feature from another and do not limit the features. Thus, the first lens discussed below could also be referred to as the second lens or the third lens without departing from the teachings of this application.

[0051] In the drawings, the thickness, size, and shape of the lenses are slightly exaggerated for ease of illustration. Specifically, the shapes of the spherical and aspherical surfaces shown in the drawings are provided by way of example. That is, the shapes of the spherical and aspherical surfaces are not limited to those shown in the drawings. The drawings are for illustration only and are not drawn strictly to scale.

[0052] In this article, the paraxial region refers to the area near the optical axis. If a lens surface is convex and the location of the convex surface is undefined, it means that the lens surface is convex at least in the paraxial region. If a lens surface is concave and the location of the concave surface is undefined, it means that the lens surface is concave at least in the paraxial region. The surface of each lens closest to the eye (i.e., the imaging side) is called the near-imaging side of the lens, and the surface of each lens closest to the image source is called the near-image source side of the lens.

[0053] 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 preclude 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 list of 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.

[0054] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It should also be understood that terms (such as those defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology and will not be interpreted in an idealized or overly formal sense unless expressly defined as such herein.

[0055] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this 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.

[0056] The features, principles and other aspects of the present application are described in detail below.

[0057] The optical lens according to an exemplary embodiment of the present application can be used as a projection lens and includes five lenses having optical power: a first lens, a second lens, a third lens, a fourth lens, and a fifth lens. These five lenses are arranged in sequence along the optical axis from the eye (i.e., the imaging side) to the image source side. Any two adjacent lenses among the first through fifth lenses may be spaced apart.

[0058] In an exemplary embodiment, the first lens may have positive or negative power, and its near-image-source side surface may be convex. For example, the paraxial region of its near-image-source side surface may be convex. The second lens may have negative power, and its near-image-source side surface may be concave. The third lens may have positive power, and its near-image-forming side surface may be convex, and its near-image-source side surface may be convex. The fourth lens may have positive or negative power, and its near-image-forming side surface may be convex. The fifth lens may have positive or negative power, and its near-image-source side surface may be concave. For example, the paraxial region of the near-image-source side surface of the first lens may be convex.

[0059] In another exemplary embodiment of the present application, the optical lens may include a first lens group with positive optical power and a second lens group with optical power in sequence from the human eye side (i.e., the imaging side) to the image source side along the optical axis. The first lens group may include a first lens, a second lens, and a third lens with optical power. The second lens group may include a fourth lens with positive optical power and a fifth lens with optical power. The side of the fifth lens near the image source may be concave. The optical power of the first lens 1 and the optical power of the second lens 2 can satisfy: 1× 2<0, for example, when the first lens has positive power, the second lens may have negative power. At least one of the first lens, the second lens, and the third lens has a convex surface near the imaging side and a convex surface near the image source side.

[0060] In an exemplary embodiment, the optical lens according to the present application may satisfy the following relationship: 0.3 < (CT4 + T45 + CT5) / Tr1r6 < 0.7, where Tr1r6 is the distance on the optical axis from the near imaging side of the first lens to the near image source side of the third lens, CT4 is the center thickness of the fourth lens, T45 is the distance on the optical axis from the near image source side of the fourth lens to the near imaging side of the fifth lens, and CT5 is the center thickness of the fifth lens. More specifically, Tr1r6, CT4, T45, and CT5 may further satisfy the following relationship: 0.2 < (CT4 + T45 + CT5) / Tr1r6 < 0.5. Satisfying 0.3 < (CT4 + T45 + CT5) / Tr1r6 < 0.7 facilitates compactness of the optical lens, enabling the optical lens to have both good projection quality and a small form factor.

[0061] In an exemplary embodiment, the optical lens according to the present application may satisfy the following relationship: -1.3 < R6 / f < -0.9, where R6 is the radius of curvature of the near-image-source side of the third lens element, and f is the total effective focal length of the optical lens. Meeting the condition of -1.3 < R6 / f < -0.9 facilitates compactness of the optical lens, enabling it to achieve both good projection quality and a small form factor.

[0062] In exemplary embodiments, the optical lens according to the present application may satisfy the following relationship: ET3 / ET2 < 0.5, where ET3 is the edge thickness of the third lens element at its maximum effective radius, and ET2 is the edge thickness of the second lens element at its maximum effective radius. More specifically, ET3 and ET2 may further satisfy the following relationship: 0.1 < ET3 / ET2 < 0.5. This ET3 / ET2 < 0.5 relationship facilitates correction of lens chromatic aberration and ensures the manufacturability of the second and third lenses.

[0063] In an exemplary embodiment, the optical lens according to the present application may satisfy the following relationship: 1.2 < (CT4 + CT5) / (ET4 + ET5) < 2.0, where CT4 is the center thickness of the fourth lens element, CT5 is the center thickness of the fifth lens element, ET4 is the edge thickness of the fourth lens element at its maximum effective radius, and ET5 is the edge thickness of the fifth lens element at its maximum effective radius. Satisfying 1.2 < (CT4 + CT5) / (ET4 + ET5) < 2.0 facilitates correction of lens chromatic aberration and ensures the manufacturability of the fourth and fifth lenses.

[0064] In an exemplary embodiment, the optical lens according to the present application can satisfy the following condition: 1 < DT32 / DT41 < 1.5, where DT32 is the maximum effective radius of the side of the third lens element near the image source, and DT41 is the maximum effective radius of the side of the fourth lens element near the image formation. This condition of 1 < DT32 / DT41 < 1.5 effectively corrects coma in off-axis fields of view, reducing edge smearing in the visual experience.

[0065] In exemplary embodiments, the optical lens according to the present application can satisfy the following condition: 0.8 < DT12 / DT21 < 1.1, where DT12 is the maximum effective radius of the side of the first lens element near the image source, and DT21 is the maximum effective radius of the side of the second lens element near the image formation. This condition can effectively eliminate astigmatism, improve projection quality, and enhance the lens's ease of assembly.

[0066] In an exemplary embodiment, the optical lens according to the present application may satisfy the following relationship: -1.1 < SAG32 / SAG41 < -0.7, where SAG32 is the distance on the optical axis from the intersection of the near image source side surface of the third lens element and the optical axis to the vertex of the effective radius of the near image source side surface of the third lens element, and SAG41 is the distance on the optical axis from the intersection of the near image side surface of the fourth lens element and the optical axis to the vertex of the effective radius of the near image side surface of the fourth lens element. Meeting the condition of -1.1 < SAG32 / SAG41 < -0.7 facilitates coma correction and improves resolution in the peripheral field of view.

[0067] In an exemplary embodiment, the optical lens according to the present application can satisfy the following condition: 0.6 < (DT32 - DT41) / (DT41 - DT52) < 1.3, where DT32 is the maximum effective radius of the near-image-source side of the third lens element, DT41 is the maximum effective radius of the near-image-forming side of the fourth lens element, and DT52 is the maximum effective radius of the near-image-source side of the fifth lens element. This condition, 0.6 < (DT32 - DT41) / (DT41 - DT52) < 1.3, effectively corrects coma in off-axis fields of view. When this optical lens is used in wearable devices such as VR, it can reduce edge smearing in the visual experience.

[0068] In an exemplary embodiment, the optical lens according to the present application may satisfy: 2< SAG21 / CT2 + SAG22 / CT2 <5.5, where SAG21 is the distance from the intersection of the near imaging side surface of the second lens and the optical axis to the vertex of the effective radius of the near imaging side surface of the second lens on the optical axis, SAG22 is the distance from the intersection of the near image source side surface of the second lens and the optical axis to the vertex of the effective radius of the near image source side surface of the second lens on the optical axis, and CT2 is the center thickness of the second lens on the optical axis. Satisfying 2< SAG21 / CT2 + SAG22 / CT2 <5.5, which is beneficial to reducing the spherical aberration and chromatic aberration of the lens, so that the lens can obtain better projection quality and reduce the color fringing phenomenon in the visual experience.

[0069] In an exemplary embodiment, the optical lens according to the present application may satisfy the following condition: 0.6 < (T12 + T23) / ∑AT < 1, where T12 is the distance on the optical axis from the near image source side of the first lens to the near imaging side of the second lens, T23 is the distance on the optical axis from the near image source side of the second lens to the near imaging side of the third lens, and ∑AT is the sum of the air spaces on the optical axis between any two adjacent lenses from the first to fifth lenses. Satisfying 0.6 < (T12 + T23) / ∑AT < 1 facilitates correction of field curvature aberrations in off-axis fields of view and reduces the overall length of the optical lens.

[0070] In an exemplary embodiment, the optical lens according to the present application may satisfy the following relationship: -1 < f2 / f1 < -0.3, where f2 is the effective focal length of the second lens element and f1 is the effective focal length of the first lens element. More specifically, f2 and f1 may further satisfy the following relationship: -0.9 < f2 / f1 < -0.5. This relationship, -1 < f2 / f1 < -0.3, facilitates correction of axial chromatic aberration and improves image sharpness in the central region of the image source plane.

[0071] In exemplary embodiments, the optical lens according to the present application can satisfy the following condition: 0.4 < DTmax / TD < 0.7, where DTmax is the maximum effective radius from the near imaging side of the first lens element to the near image source side of the fifth lens element, and TD is the distance along the optical axis from the near imaging side of the first lens element to the near image source side of the fifth lens element. This condition allows for a wider eye movement range in eyepiece usage scenarios, resulting in a more comfortable viewing experience.

[0072] In an exemplary embodiment, the optical lens according to the present application may satisfy the following relationship: 3 < TD / ImgH < 4.5, where TD is the distance on the optical axis from the near-imaging side surface of the first lens element to the near-image source side surface of the fifth lens element, and ImgH is half the diagonal length of the image source surface of the optical lens. Satisfying 3 < TD / ImgH < 4.5 allows the optical lens to have a shorter overall length, thereby meeting requirements for lens miniaturization.

[0073] In an exemplary embodiment, the optical lens according to the present application can satisfy the following condition: 0.6 < ∑ET / ∑CT < 1, where ∑ET is the sum of the edge thicknesses of the first through fifth lenses at their maximum effective diameter, and ∑CT is the sum of the center thicknesses of the first through fifth lenses along the optical axis. This condition facilitates the proper distribution of optical power among the lenses and effectively corrects spherical aberration and other aberrations.

[0074] In an exemplary embodiment, the optical lens according to the present application can satisfy the following condition: tan(FOV / 2)×f / EPD<1, where FOV is the maximum field of view of the optical lens, EPD is the diameter of the entrance pupil of the optical lens, and f is the total effective focal length of the optical lens. Satisfying tan(FOV / 2)×f / EPD<1 allows for a wider eye movement range in eyepiece usage scenarios while ensuring a larger field of view, thereby improving user convenience.

[0075] In an exemplary embodiment, the optical lens according to the present application may satisfy the following requirement: f × tan(FOV / 4) < 6 mm, where f is the total effective focal length of the optical lens and FOV is the maximum field of view of the optical lens. More specifically, f and FOV may further satisfy the following requirement: f × tan(FOV / 4) < 4 mm. This requirement of f × tan(FOV / 4) < 6 mm effectively corrects various aberrations and facilitates a larger field of view for the imaging lens, providing users with a better sense of immersion.

[0076] In an exemplary embodiment, the optical lens according to the present application may satisfy the following conditions: 0 < (N1max - N1_2) / N1_2 < 0.5, where N1max is the maximum refractive index of the first to third lenses, and N1_2 is the refractive index of the second lens. More specifically, N1max and N1_2 may further satisfy the following conditions: 0 < (N1max - N1_2) / N1_2 < 0.2. When 0 < (N1max - N1_2) / N1_2 < 0.5 is satisfied, when the optical lens is mounted on wearable devices such as VR, it is beneficial to correct vertical chromatic aberration within the wearer's eye movement range, ensuring a smooth visual experience.

[0077] In exemplary embodiments, the optical lens according to the present application may satisfy the following relationship: 1 < f123 / f < 2, where f123 is the combined focal length of the first, second, and third lenses, and f is the total effective focal length of the optical lens. This relationship facilitates correction of spherical aberration in the lens.

[0078] In an exemplary embodiment, the total effective focal length f of the optical lens may be in the range of 13 mm to 15 mm; the effective focal length f1 of the first lens may be in the range of 12.5 mm to 19.0 mm; the effective focal length f2 of the second lens may be in the range of -15.5 mm to -7.5 mm; and the effective focal length f3 of the third lens may be in the range of 13.0 mm to 16.0 mm.

[0079] In an exemplary embodiment, the distance TTL from the near imaging side surface of the first lens to the image source surface of the optical lens on the optical axis may be in the range of 29 mm to 35 mm; half the diagonal length of the image source surface of the optical lens ImgH may be in the range of 6.0 mm to 9.0 mm; the maximum field of view FOV of the optical lens may be in the range of 53.5° to 58.5°; and the aperture value Fno of the optical lens may be in the range of 1.4 to 1.8.

[0080] In an exemplary embodiment, the optical lens according to the present application further includes an aperture (not shown) disposed between the imaging side and the first lens element. The aperture can be positioned, for example, near the human eye's observation area. Optionally, the optical lens can further include a filter for correcting chromatic aberration and / or a protective glass for protecting the photosensitive element located on the image source surface.

[0081] The optical lens according to the above embodiment of the present application may use multiple lenses, such as the five lenses described above. By rationally allocating the optical power, surface shape, center thickness of each lens, and the on-axis spacing between lenses, the volume of the optical lens can be effectively reduced and the processability of the optical lens can be improved, making the optical lens more conducive to production and processing and applicable to portable electronic products. The optical lens configured as described above has the characteristics of small size, light weight, good imaging quality, etc., which can well meet the use requirements of various portable electronic products such as VR head-mounted devices in projection scenarios.

[0082] In an embodiment of the present application, at least one of the mirror surfaces of each lens is an aspherical surface, that is, at least one of the mirror surfaces from the near-image side of the first lens to the near-image source side of the fifth lens is an aspherical surface. A characteristic of an aspherical lens is that its curvature continuously changes from the center of the lens to the periphery. Unlike spherical lenses, which have a constant curvature from the center to the periphery, aspherical lenses have a better curvature radius characteristic, with the advantages of improving distortion aberration and astigmatism. The use of aspherical lenses can minimize aberrations that occur during projection, thereby improving projection quality. Optionally, at least one of the near-image side and the near-image source side of each of the first, second, third, fourth, and fifth lenses is an aspherical surface. Optionally, both the near-image side and the near-image source side of each of the first, second, third, fourth, and fifth lenses are aspherical surfaces.

[0083] However, those skilled in the art will appreciate that the number of lenses comprising the optical lens may be varied to achieve the various results and advantages described herein without departing from the claimed technical solutions. For example, while the embodiments describe an optical lens with five lenses as an example, the optical lens is not limited to including five lenses. If desired, the optical lens may also include other numbers of lenses.

[0084] Specific embodiments of the optical lens applicable to the above-mentioned embodiments will be further described below with reference to the accompanying drawings.

[0085] Example 1

[0086] The following reference Figures 1 to 2D The optical lens according to Example 1 of the present application is described. Figure 1 A schematic structural diagram of an optical lens according to Example 1 of the present application is shown.

[0087] like Figure 1 As shown, the optical lens comprises, from the imaging side to the image source side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6 and an image source surface S13.

[0088] The first lens E1 has positive focal power, with its near-image-surface S1 being concave and its near-image-source side S2 being convex. The second lens E2 has negative focal power, with its near-image-surface S3 being convex and its near-image-source side S4 being concave. The third lens E3 has positive focal power, with its near-image-surface S5 being convex and its near-image-source side S6 being convex. The fourth lens E4 has positive focal power, with its near-image-surface S7 being convex and its near-image-source side S8 being convex. The fifth lens E5 has negative focal power, with its near-image-surface S9 being concave and its near-image-source side S10 being concave. The filter E6 has a near-image-surface S11 and a near-image-source side S12. Light from the image source surface S13 sequentially passes through each surface S12 to S1 and is ultimately projected onto a target object (not shown) in space. For example, when the optical lens is mounted on a wearable device such as VR, light from the image source surface S13 passes through the surfaces S12 to S1 in sequence and is finally projected into the wearer's eye EYE.

[0089] Table 1 shows the basic parameters of the optical lens of Example 1, wherein the units of curvature radius, thickness / distance and focal length are all millimeters (mm).

[0090]

[0091] Table 1

[0092] In this example, the total effective focal length f of the optical lens is 13.12 mm, the total length TTL of the optical lens (i.e., the distance from the near imaging side S1 of the first lens E1 to the image source surface S13 of the optical lens on the optical axis) is 30.28 mm, half the diagonal length ImgH of the image source surface S13 of the optical lens is 6.45 mm, the maximum field of view FOV of the optical lens is 54.31°, and the aperture value Fno of the optical lens is 1.46.

[0093] In Example 1, the near-image-forming side surface and the near-image-source side surface of any lens from the first lens E1 to the third lens E3 are both aspherical surfaces, and the surface shape of each aspherical lens is The following aspheric formulas can be used for definition, but are not limited to:

[0094] (1)

[0095] in, Aspheric surface along the optical axis at a height of h When the position is , the distance from the vertex of the aspherical surface is high; c is the paraxial curvature of the aspheric surface, c =1 / R (i.e., paraxial curvature c is the reciprocal of the curvature radius R in Table 1 above); k is the cone coefficient; Ai Aspheric iTable 2 below lists the high-order coefficients that can be used for each aspherical mirror surface S1-S6 in Example 1. A 4 、 A 6 、 A 8 、 A 10 、 A 12 、 A 14 and A 16 .

[0096]

[0097] Table 2

[0098] Figure 2A The axial chromatic aberration curve of the optical lens of Example 1 is shown, which indicates the deviation of the focusing point of light of different wavelengths passing through the lens. Figure 2B The astigmatism curve of the optical lens of Example 1 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 2C The distortion curve of the optical lens of Example 1 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 2D The relative illumination curve of the optical lens of Example 1 is shown, which represents the relative illumination values ​​corresponding to different image heights. Figures 2A to 2D It can be seen that the optical lens provided in Example 1 can achieve good imaging quality.

[0099] Example 2

[0100] The following reference Figures 3 to 4D The optical lens according to Example 2 of the present application is described. In this embodiment and the following embodiments, some descriptions similar to those in Example 1 will be omitted for the sake of brevity. Figure 3 A schematic structural diagram of an optical lens according to Example 2 of the present application is shown.

[0101] like Figure 3 As shown, the optical lens comprises, from the imaging side to the image source side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6 and an image source surface S13.

[0102] The first lens E1 has positive focal power, with its near-image-surface S1 being concave and its near-image-source side S2 being convex. The second lens E2 has negative focal power, with its near-image-surface S3 being convex and its near-image-source side S4 being concave. The third lens E3 has positive focal power, with its near-image-surface S5 being convex and its near-image-source side S6 being convex. The fourth lens E4 has positive focal power, with its near-image-surface S7 being convex and its near-image-source side S8 being convex. The fifth lens E5 has negative focal power, with its near-image-surface S9 being concave and its near-image-source side S10 being concave. The filter E6 has a near-image-surface S11 and a near-image-source side S12. Light from the image source surface S13 sequentially passes through each surface S12 to S1 and is ultimately projected onto a target object (not shown) in space. For example, when the optical lens is mounted on a wearable device such as VR, light from the image source surface S13 passes through the surfaces S12 to S1 in sequence and is finally projected into the wearer's eye EYE.

[0103] In this example, the total effective focal length f of the optical lens is 13.47 mm, the total length TTL of the optical lens is 30.01 mm, half the diagonal length ImgH of the image source surface S13 of the optical lens is 6.45 mm, the maximum field of view FOV of the optical lens is 53.93°, and the aperture value Fno of the optical lens is 1.49.

[0104] Table 3 shows the basic parameters of the optical lens of Example 2, where the units of curvature radius, thickness / distance, and focal length are all in millimeters (mm). Table 4 shows the high-order coefficients of each aspherical mirror surface that can be used in Example 2, where the surface shape of each aspherical surface can be defined by formula (1) given in Example 1 above.

[0105]

[0106] Table 3

[0107]

[0108] Table 4

[0109] Figure 4A The axial chromatic aberration curve of the optical lens of Example 2 is shown, which indicates the deviation of the focusing point of light of different wavelengths passing through the lens. Figure 4B The astigmatism curve of the optical lens of Example 2 is shown, which indicates meridional field curvature and sagittal field curvature. Figure 4C The distortion curve of the optical lens of Example 2 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 4D The relative illumination curve of the optical lens of Example 2 is shown, which represents the relative illumination values ​​corresponding to different image heights. Figures 4A to 4D It can be seen that the optical lens provided in Example 2 can achieve good imaging quality.

[0110] Example 3

[0111] The following reference Figures 5 to 6D An optical lens according to Example 3 of the present application is described. Figure 5 A schematic structural diagram of an optical lens according to Example 3 of the present application is shown.

[0112] like Figure 5 As shown, the optical lens comprises, from the imaging side to the image source side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6 and an image source surface S13.

[0113] The first lens E1 has positive focal power, with its near-image-surface S1 being convex and its near-image-source-surface S2 being convex. The second lens E2 has negative focal power, with its near-image-surface S3 being concave and its near-image-source-surface S4 being concave. The third lens E3 has positive focal power, with its near-image-surface S5 being convex and its near-image-source-surface S6 being convex. The fourth lens E4 has positive focal power, with its near-image-surface S7 being convex and its near-image-source-surface S8 being concave. The fifth lens E5 has negative focal power, with its near-image-surface S9 being concave and its near-image-source-surface S10 being concave. The filter E6 has a near-image-surface S11 and a near-image-source-surface S12. Light from the image-source surface S13 sequentially passes through each surface S12 to S1 and is ultimately projected onto a target object (not shown) in space. For example, when the optical lens is mounted on a wearable device such as VR, light from the image source surface S13 passes through the surfaces S12 to S1 in sequence and is finally projected into the wearer's eye EYE.

[0114] In this example, the total effective focal length f of the optical lens is 13.50 mm, the total length TTL of the optical lens is 29.14 mm, half the diagonal length ImgH of the image source surface S13 of the optical lens is 6.45 mm, the maximum field of view FOV of the optical lens is 53.86°, and the aperture value Fno of the optical lens is 1.69.

[0115] Table 5 shows the basic parameters of the optical lens of Example 3, where the units of curvature radius, thickness / distance, and focal length are all in millimeters (mm). Table 6 shows the high-order coefficients of each aspherical mirror surface that can be used in Example 3, where the surface shape of each aspherical surface can be defined by formula (1) given in Example 1 above.

[0116]

[0117] Table 5

[0118]

[0119] Table 6

[0120] Figure 6A The axial chromatic aberration curve of the optical lens of Example 3 is shown, which indicates the deviation of the focusing point of light of different wavelengths passing through the lens. Figure 6B The astigmatism curve of the optical lens of Example 3 is shown, which indicates the meridional field curvature and the sagittal field curvature. Figure 6C The distortion curve of the optical lens of Example 3 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 6D The relative illumination curve of the optical lens of Example 3 is shown, which represents the relative illumination values ​​corresponding to different image heights. 6A to 6D It can be seen that the optical lens provided in Example 3 can achieve good imaging quality.

[0121] Example 4

[0122] The following reference Figures 7 to 8D An optical lens according to Example 4 of the present application is described. Figure 7 A schematic structural diagram of an optical lens according to Example 4 of the present application is shown.

[0123] like Figure 7 As shown, the optical lens comprises, from the imaging side to the image source side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6 and an image source surface S13.

[0124] The first lens E1 has positive optical power, with its near-image-surface S1 being convex and its near-image-source-surface S2 being convex. The second lens E2 has negative optical power, with its near-image-surface S3 being concave and its near-image-source-surface S4 being concave. The third lens E3 has positive optical power, with its near-image-surface S5 being convex and its near-image-source-surface S6 being convex. The fourth lens E4 has positive optical power, with its near-image-surface S7 being convex and its near-image-source-surface S8 being concave. The fifth lens E5 has positive optical power, with its near-image-surface S9 being convex and its near-image-source-surface S10 being concave. The filter E6 has a near-image-surface S11 and a near-image-source-surface S12. Light from the image-source surface S13 sequentially passes through each surface S12 to S1 and is ultimately projected onto a target object (not shown) in space. For example, when the optical lens is mounted on a wearable device such as VR, light from the image source surface S13 passes through the surfaces S12 to S1 in sequence and is finally projected into the wearer's eye EYE.

[0125] In this example, the total effective focal length f of the optical lens is 14.82 mm, the total length TTL of the optical lens is 34.73 mm, half the diagonal length ImgH of the image source surface S13 of the optical lens is 7.52 mm, the maximum field of view FOV of the optical lens is 57.14°, and the aperture value Fno of the optical lens is 1.65.

[0126] Table 7 shows the basic parameters of the optical lens of Example 4, where the units of curvature radius, thickness / distance, and focal length are all in millimeters (mm). Table 8 shows the high-order coefficients of each aspherical mirror surface that can be used in Example 4, where the surface shape of each aspherical surface can be defined by formula (1) given in Example 1 above.

[0127]

[0128] Table 7

[0129]

[0130] Table 8

[0131] Figure 8A The axial chromatic aberration curve of the optical lens of Example 4 is shown, which indicates the deviation of light of different wavelengths from the focal point behind the lens. Figure 8B The astigmatism curve of the optical lens of Example 4 is shown, which indicates the meridional field curvature and the sagittal field curvature. Figure 8C The distortion curve of the optical lens of Example 4 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 8D The relative illumination curve of the optical lens of Example 4 is shown, which represents the relative illumination values ​​corresponding to different image heights. Figures 8A to 8D It can be seen that the optical lens provided in Example 4 can achieve good imaging quality.

[0132] Example 5

[0133] The following reference Figures 9 to 10D An optical lens according to Example 5 of the present application is described. Figure 9 A structural schematic diagram of an optical lens according to Example 5 of the present application is shown.

[0134] like Figure 9 As shown, the optical lens comprises, from the imaging side to the image source side, a first lens E1, a second lens E2, a third lens E3, a fourth lens E4, a fifth lens E5, a filter E6 and an image source surface S13.

[0135] The first lens E1 has positive focal power, with its near-image-surface S1 being convex and its near-image-source side S2 being convex. The second lens E2 has negative focal power, with its near-image-surface S3 being concave and its near-image-source side S4 being concave. The third lens E3 has positive focal power, with its near-image-surface S5 being convex and its near-image-source side S6 being convex. The fourth lens E4 has positive focal power, with its near-image-surface S7 being convex and its near-image-source side S8 being concave. The fifth lens E5 has negative focal power, with its near-image-surface S9 being convex and its near-image-source side S10 being concave. The filter E6 has a near-image-surface S11 and a near-image-source side S12. Light from the image source surface S13 sequentially passes through each surface S12 to S1 and is ultimately projected onto a target object (not shown) in space. For example, when the optical lens is mounted on a wearable device such as VR, light from the image source surface S13 passes through the surfaces S12 to S1 in sequence and is finally projected into the wearer's eye EYE.

[0136] In this example, the total effective focal length f of the optical lens is 13.57 mm, the total length TTL of the optical lens is 32.25 mm, half the diagonal length ImgH of the image source surface S13 of the optical lens is 8.87 mm, the maximum field of view FOV of the optical lens is 58.34°, and the aperture value Fno of the optical lens is 1.51.

[0137] Table 9 shows the basic parameters of the optical lens of Example 5, where the units of curvature radius, thickness / distance, and focal length are all in millimeters (mm). Table 10 shows the high-order coefficients of each aspherical mirror surface that can be used in Example 5, where the surface shape of each aspherical surface can be defined by formula (1) given in Example 1 above.

[0138]

[0139] Table 9

[0140]

[0141] Table 10

[0142] Figure 10A The axial chromatic aberration curve of the optical lens of Example 5 is shown, which indicates the deviation of the focusing point of light of different wavelengths passing through the lens. Figure 10B The astigmatism curve of the optical lens of Example 5 is shown, which indicates the meridional field curvature and the sagittal field curvature. Figure 10C The distortion curve of the optical lens of Example 5 is shown, which represents the distortion magnitude values ​​corresponding to different image heights. Figure 10D The relative illumination curve of the optical lens of Example 5 is shown, which represents the relative illumination values ​​corresponding to different image heights. 10A to 10D It can be seen that the optical lens provided in Example 5 can achieve good imaging quality.

[0143] In summary, Examples 1 to 5 respectively satisfy the relationships shown in Table 11.

[0144]

[0145] Table 11

[0146] The present application also provides a projection device, whose electronic photosensitive element can be a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS). The projection device can be a standalone projection device such as a projector, or a projection module integrated into a mobile electronic device such as a VR device. The projection device is equipped with the optical lens described above.

[0147] The above description is merely a preferred embodiment of the present application and an illustration of the technical principles employed. Those skilled in the art should understand that the scope of the invention herein is not limited to technical solutions formed by a specific combination of the aforementioned technical features. It also encompasses other technical solutions formed by any combination of the aforementioned technical features or their equivalents, without departing from the inventive concept. For example, a technical solution formed by replacing the aforementioned features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. An optical lens, characterized in that: Along the optical axis from the human eye side to the image source side, it includes: The first lens has positive refractive power and a convex surface near the image source; The second lens has a negative optical power and a concave surface near the image source; The third lens has positive refractive power, and its side closest to the human eye is convex, and its side closest to the image source is also convex; The fourth lens element has positive refractive power and a convex surface on the side closest to the human eye; a fifth lens element having optical power and a concave surface on the side near the image source; The number of lenses having optical power in the optical lens is five; The optical lens satisfies the following conditions: 0.3<(CT4+T45+CT5) / Tr1r6≤0.44 and -1.16≤R6 / f≤-1.00, wherein Tr1r6 is the distance from the side of the first lens near the human eye to the side of the third lens near the image source on the optical axis, CT4 is the center thickness of the fourth lens, T45 is the distance from the side of the fourth lens near the image source to the side of the fifth lens near the human eye on the optical axis, CT5 is the center thickness of the fifth lens, R6 is the radius of curvature of the side of the third lens near the image source, and f is the total effective focal length of the optical lens.

2. The optical lens according to claim 1, wherein: The optical lens satisfies: 0.17≤ET3 / ET2≤0.33, wherein ET3 is the edge thickness of the third lens at the maximum effective radius, and ET2 is the edge thickness of the second lens at the maximum effective radius.

3. The optical lens according to claim 1, wherein: The optical lens satisfies: 1.2<(CT4+CT5) / (ET4+ET5)<2.0, wherein ET4 is the edge thickness of the fourth lens at the maximum effective radius, and ET5 is the edge thickness of the fifth lens at the maximum effective radius.

4. The optical lens according to claim 1, wherein: The optical lens satisfies: 1.19≤DT32 / DT41≤1.24, wherein DT32 is the maximum effective radius of the side of the third lens near the image source, and DT41 is the maximum effective radius of the side of the fourth lens near the human eye.

5. The optical lens according to claim 1, wherein: The optical lens satisfies: 0.86≤DT12 / DT21≤1.01, wherein DT12 is the maximum effective radius of the side of the first lens near the image source, and DT21 is the maximum effective radius of the side of the second lens near the human eye.

6. The optical lens according to claim 1, wherein: The optical lens satisfies: -1.1<SAG32 / SAG41<-0.7, wherein SAG32 is the distance from the intersection of the near image source side of the third lens and the optical axis to the vertex of the effective radius of the near image source side of the third lens on the optical axis, and SAG41 is the distance from the intersection of the near human eye side of the fourth lens and the optical axis to the vertex of the effective radius of the near human eye side of the fourth lens on the optical axis.

7. The optical lens according to claim 1, wherein: The optical lens satisfies the following conditions: 0.67≤(DT32-DT41) / (DT41-DT52)≤1.23, where DT32 is the maximum effective radius of the side of the third lens near the image source, DT41 is the maximum effective radius of the side of the fourth lens near the human eye, and DT52 is the maximum effective radius of the side of the fifth lens near the image source.

8. The optical lens according to claim 1, wherein: The optical lens meets the following requirements: 2.08≤ SAG21 / CT2 + SAG22 / CT2 ≤5.14, where SAG21 is the distance from the intersection of the side surface near the human eye of the second lens and the optical axis to the vertex of the effective radius of the side surface near the human eye of the second lens on the optical axis, SAG22 is the distance from the intersection of the side surface near the image source of the second lens and the optical axis to the vertex of the effective radius of the side surface near the image source of the second lens on the optical axis, and CT2 is the center thickness of the second lens on the optical axis.

9. The optical lens according to claim 1, wherein: The optical lens satisfies the following condition: 0.6<(T12+T23) / ∑AT<1, where T12 is the distance on the optical axis from the near image source side of the first lens to the near human eye side of the second lens, T23 is the distance on the optical axis from the near image source side of the second lens to the near human eye side of the third lens, and ∑AT is the sum of the air spaces on the optical axis between any two adjacent lenses from the first lens to the fifth lens.

10. The optical lens according to claim 1, wherein: The optical lens satisfies: -0.81≤f2 / f1≤-0.61, wherein f2 is the effective focal length of the second lens, and f1 is the effective focal length of the first lens.

11. The optical lens according to any one of claims 1 to 10, characterized in that: The optical lens satisfies the following condition: 0.45≤DTmax / TD≤0.51, where DTmax is the maximum value of the maximum effective radius from the side near the human eye of the first lens to the side near the image source of the fifth lens, and TD is the distance on the optical axis from the side near the human eye of the first lens to the side near the image source of the fifth lens.

12. The optical lens according to any one of claims 1 to 10, characterized in that: The optical lens satisfies the following conditions: 3.29≤TD / ImgH≤4.05, wherein TD is the distance on the optical axis from the side of the first lens near the human eye to the side of the fifth lens near the image source, and ImgH is half the diagonal length of the image source surface of the optical lens.

13. The optical lens according to any one of claims 1 to 10, characterized in that: The optical lens satisfies the following: 0.65≤∑ET / ∑CT≤0.77, where ∑ET is the sum of edge thicknesses of the first to fifth lenses at a maximum effective diameter, and ∑CT is the sum of center thicknesses of the first to fifth lenses on the optical axis.

14. The optical lens according to any one of claims 1 to 10, characterized in that: The optical lens satisfies: 0.75≤tan(FOV / 2)×f / EPD≤0.90, wherein FOV is the maximum field of view of the optical lens, and EPD is the entrance pupil diameter of the optical lens.

15. The optical lens according to any one of claims 1 to 10, characterized in that: The optical lens satisfies the following: 1.27≤f123 / f≤1.88, where f123 is the combined focal length of the first lens, the second lens, and the third lens.

16. The optical lens according to claim 1, wherein: The optical lens satisfies the following conditions: 3.17 mm ≤ f × ​​tan (FOV / 4) ≤ 3.77 mm, where f is the total effective focal length of the optical lens, and FOV is the maximum field of view of the optical lens.

Images