Lenses, projection optics and near-eye display systems

Abstract

The embodiment of the present application provides a lens, a projection optical machine and a near-eye display system. The lens can be applied to the projection optical machine, and the projection optical machine can be applied to the near-eye display system. The lens includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence along the optical axis direction. The first lens is used to converge the effective light signal emitted by the display to form a first transmitted light signal, the second lens is used to converge the first transmitted light signal to form a second transmitted light signal, the third lens is used to disperse the second transmitted light signal to form a third transmitted light signal, the fourth lens is used to disperse the third transmitted light signal to form a fourth transmitted light signal, and the fifth lens is used to converge the fourth transmitted light signal to form a fifth transmitted light signal. The lens of the embodiment of the present application can modulate the effective light signal emitted by the display to reduce aberrations.

Description

Technical Field

[0001] The present application relates to the field of display projection technology, and in particular to a lens, a projection optical machine, and a near-eye display system. Background Art

[0002] With the continuous development of augmented reality technology, head-mounted augmented reality devices such as smart glasses or smart masks have been widely accepted and used by users.

[0003] An augmented reality device may generally include a projector and a camera. The projector may generate a virtual image. The light of the virtual image and the light of the real environment may simultaneously enter the pupil of a user wearing the augmented reality device, so that the user wearing the augmented reality device can not only see real objects but also virtual images. Summary of the invention

[0004] The embodiments of the present application provide a lens, a projection optical machine, and a near-eye display system. The lens can be applied to the projection optical machine to modulate the effective light signal emitted by the projection optical machine.

[0005] An embodiment of the present application provides a lens, comprising a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence along an optical axis direction, wherein the first lens is used to converge an effective light signal emitted by a display to form a first transmitted light signal, the second lens is used to converge the first transmitted light signal to form a second transmitted light signal, the third lens is used to disperse the second transmitted light signal to form a third transmitted light signal, the fourth lens is used to disperse the third transmitted light signal to form a fourth transmitted light signal, and the fifth lens is used to converge the fourth transmitted light signal to form a fifth transmitted light signal.

[0006] An embodiment of the present application provides a projection optical machine, including a lens and a display, wherein the lens is the lens as described in the above embodiment of the application, and the display is used to emit a valid light signal. The display is arranged on one side of the lens and adjacent to the first lens so that the valid light signal can be injected into the first lens.

[0007] The embodiment of the present application provides a near-eye display system, including:

[0008] A display, wherein pixels of the display emit effective light signals with different emission angles, and the effective light signals include image information;

[0009] A lens, arranged at one side of the display, for receiving the effective light signal and modulating the effective light signal, so that the effective light signal generated by one pixel point forms parallel light beams with different emission angles after passing through the lens;

[0010] A waveguide element is arranged on a side of the lens away from the display, and the waveguide element is used to receive the parallel light beams and convert the parallel light beams into a virtual image.

[0011] The lens of the embodiment of the present application includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence along the optical axis direction. The effective light signal emitted by the display passes through the five lenses in sequence. The five lenses can modulate the effective light signal to reduce aberrations. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without creative work.

[0013] Figure 1 The first structural intention of the projection optical machine provided in the embodiment of the present application.

[0014] Figure 2 for Figure 1 The modulation transfer function diagram of the lens in the projection optical machine shown.

[0015] Figure 3 for Figure 1 Field curvature diagram of the lens in the projection optical machine shown.

[0016] Figure 4 for Figure 1 The distortion curve of the lens in the projection optical machine shown.

[0017] Figure 5 for Figure 1 The defocus curve of the lens in the projection optical machine shown.

[0018] Figure 6 A schematic diagram of the structure of a near-eye display system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application.

[0020] The present application embodiment provides a projection optical machine, which is used to generate a virtual image. Figure 1 As shown, Figure 1The first structural intention of the projection optical machine provided in the embodiment of the present application. The projection optical machine 200 includes a display 220 and a lens 240, and the lens 240 is arranged on one side of the display 220. The display 220 can emit a light signal, wherein the light signal that can generate a virtual image is an effective light signal, and the effective light signal can be transmitted through the lens 240. The lens 240 can correct the virtual image to reduce various aberrations and improve the imaging quality of the virtual image. The lens 240 may include a first lens 241, a second lens 242, a third lens 243, a fourth lens 244, and a fifth lens 245 arranged in sequence from the image source side to the imaging side along the optical axis direction (or the light transmission direction for generating the virtual image), and the first lens 241 is arranged adjacent to the display 220. It can be understood that the first lens 241, the second lens 242, the third lens 243, the fourth lens 244, and the fifth lens 245 are arranged in sequence from the image source side to the imaging side.

[0021] Among them, the first lens 241 can receive the effective light signal emitted by the display 220 and converge the effective light signal to form a first transmitted light signal, the second lens 242 can receive and converge the first transmitted light signal to form a second transmitted light signal, the third lens 243 can receive and disperse the second transmitted light signal to form a third transmitted light signal, the fourth lens 244 can receive and disperse the third transmitted light signal to form a fourth transmitted light signal, and the fifth lens 245 can receive and converge the fourth transmitted light signal to form a fifth transmitted light signal. For example, the first lens 241 may be a positive power lens, which has a converging effect on the effective light signal, and the effective light signal may form a first transmitted light signal after passing through the first lens 241; the second lens 242 may be a positive power lens, which has a converging effect on the first transmitted light signal, and the first transmitted light signal may form a second transmitted light signal after passing through the second lens 242; the third lens 243 may be a negative power lens, which has a diverging effect on the second transmitted light signal, and the second transmitted light signal may form a third transmitted light signal after passing through the third lens 243; the fourth lens 244 may be a cemented lens, and the combined optical power of the cemented lens is a negative value, the fourth lens 244 has a dispersing effect on the third transmitted light signal, and the third transmitted light signal may form a fourth transmitted light signal after passing through the fourth lens 244, and the fourth lens 244 may reduce chromatic aberration or reduce chromatic aberration; the fifth lens 245 may be a positive power lens, which has a converging effect on the fourth transmitted light signal, and the fourth transmitted light signal may form a fifth transmitted light signal after passing through the fifth lens 245.

[0022] The effective light signal emitted by the display of the embodiment of the present application can pass through the first lens 241, the second lens 242, the third lens 243, the fourth lens 244 and the fifth lens 245 in sequence. The five lenses can modulate the effective light signal to reduce the aberration, thereby improving the imaging effect of the virtual image projected by the projection optical machine 200.

[0023] Please continue reading Figure 1 , the fourth lens 244 can be formed by gluing two single lenses. For example, the fourth lens 244 can include a first sub-lens 2441 and a second sub-lens 2442, and one surface of the first sub-lens 2441 and one surface of the second sub-lens 2442 are adapted to each other, so that one surface of the first sub-lens 2441 and one surface of the second sub-lens 2442 can be glued together. The first sub-lens 2441 is located between the second sub-lens 2442 and the third lens 243, and the first sub-lens 2441 is a negative optical focal length lens, which has a divergent effect on the third transmitted light signal. The second sub-lens 2442 is located between the first sub-lens 2441 and the fifth lens 245, and the second sub-lens 2442 is a positive optical focal length lens, which has a converging effect on the light signal transmitted through the first sub-lens 2441.

[0024] The display 220 in the embodiment of the present application may be a micro display, for example, the display 220 may be an organic light-emitting diode (OLED) display or a micro liquid crystal display (LCD). Under working power conditions, the brightness of the Micro-OLED is less than 5000 nits, and the brightness of the LCD is less than 15000 nits. Nits is a unit of measurement for brightness, which is a person's perception of the intensity of light and can be used to indicate the brightness of the picture. The display 220 in the embodiment of the present application may also be a micro light-emitting diode (Micro Light Emitting Diode, Micro-LED) display, for example, it may be a green light Micro-LED, or other monochrome Micro-LED or white light complex color Micro-LED. Compared with Micro-OLED and LCD, the brightness of Micro-LED can reach 2000000 nits, which is much higher than Micro-OLED and LCD. In addition, since Micro-LED is a self-luminous light source, the projection system with Micro-LED has better contrast and better display delay.

[0025] The diagonal size of the effective light-emitting area of ​​the display 220 is 0.11 inches to 0.15 inches, and the length-to-width ratio of the effective light-emitting area is 4:3. In some other embodiments, the diagonal size of the effective light-emitting area of ​​the display 220 is 0.17 inches to 0.21 inches, and the length-to-width ratio of the effective light-emitting area is 16:9. A glass cover is provided outside the effective light-emitting surface of the display 220, and the glass cover can exist in an independent form or in the form of being integrated and packaged in the display 220. The thickness of the glass cover ranges from 0.3 mm to 0.8 mm.

[0026] The display 220 generates heat during operation, and the heat generated by the display 220 is conducted to the lens 240. In order to improve the thermal stability of the lens 240, the five lenses in the embodiment of the present application are all made of glass. Compared with lenses made of plastic, lenses made of glass have better thermal stability and are not easily deformed by heat. The first lens 241, the second lens 242, the first sub-lens 2441, the second sub-lens 2442 and the fifth lens 245 in the embodiment of the present application are all spherical lenses. The use of a glass spherical surface solution for small-size optical system design can ensure the stability of the optical system over a wide range of temperature changes while achieving lower production and assembly costs.

[0027] like Figure 1As shown, the first lens 241 includes a first light incident surface S11 and a first light emitting surface S12 which are arranged opposite to each other, the first light emitting surface S12 is arranged close to the second lens 242, the first light incident surface S11 is a concave surface, and the first light incident surface S11 is formed by being concave from the image source side toward the imaging side. The first light emitting surface S12 is a convex surface, and the first light emitting surface S12 is formed by being convex from the image source side toward the imaging side. Among them, the curvature of the first light emitting surface S12 is greater than the curvature of the first light incident surface S11, for example, the curvature radius of the first light incident surface S11 can be 7.5mm, and the curvature radius of the first light emitting surface S12 can be 4.0mm. In the embodiment of the present application, the first lens 241 satisfies that the distance between the first light incident surface S11 and the display 220 is less than 4mm, for example, the distance between the first light incident surface S11 and the display 220 is 1mm, 2mm, 3mm or 3.5mm, etc. The first light incident surface S11 is a spherical structure, and the distance between the first light incident surface S11 and the display 220 refers to the distance from the spherical vertex of the first light incident surface S11 to the light-emitting surface of the display 220. In some other embodiments, the distance between the spherical vertex of the first light incident surface S11 and the display 220 is less than 2 mm. The second lens 242 includes a second light incident surface S21 and a second light emitting surface S22 that are arranged opposite to each other, and the second light incident surface S21 is located between the first light emitting surface S12 and the second light emitting surface S22. The second light incident surface S21 is a convex surface, and the second light incident surface S21 is formed by protruding from the imaging side toward the image source side. The second light emitting surface S22 is a convex surface, and the second light emitting surface S22 is formed by protruding from the image source side toward the imaging side. It should be noted that the structure of the second light emitting surface S22 is not limited to this, for example, the second light emitting surface S22 can also be a concave surface, or a plane. The second light incident surface S21 and the first light emitting surface S12 are spherical structures, and the distance between the second light incident surface S21 and the first light emitting surface S12 is less than 1 mm, for example, it can be 0.5 mm, 0.8 mm or 0.9 mm, etc. The distance between the second light incident surface S21 and the first light emitting surface S12 refers to the distance from the spherical vertex of the second light incident surface S21 to the spherical vertex of the first light emitting surface S12.

[0028] The third lens 243 includes a third light incident surface S31 and a third light emitting surface S32 which are arranged in opposite directions. The third light incident surface S31 is located between the second light emitting surface S22 and the third light emitting surface S32. The third light incident surface S31 is a concave surface, and the third light incident surface S31 is formed by being recessed from the image source side toward the imaging side. The third light emitting surface S32 is a concave surface, and the third light emitting surface S32 is formed by being recessed from the image source side toward the imaging side. It should be noted that the structure of the second light emitting surface S32 is not limited thereto, for example, the third light emitting surface S32 may also be a convex surface. Among them, the third light incident surface S31 and the second light emitting surface S22 are spherical structures, and the distance between the third light incident surface S31 and the second light emitting surface S22 is less than 0.4 mm, for example, the distance between the third light incident surface S31 and the second light emitting surface S22 may be 0.1 mm, 0.2 mm, 0.3 mm or other data. The distance between the third light incident surface S31 and the second light emitting surface S22 refers to the distance from the spherical vertex of the third light incident surface S31 to the spherical vertex of the second light emitting surface S22. In some other embodiments, the distance between the third light incident surface S31 and the second light emitting surface S22 is less than 0.2 mm.

[0029] The fourth lens 244 includes a fourth light incident surface S41 and a fourth light emitting surface S42 which are arranged in opposite directions. The fourth light incident surface S41 is located between the third light emitting surface S32 and the fourth light emitting surface S42. The fourth light incident surface S41 is a concave surface, and the fourth light incident surface S41 is formed by being concave from the image source side to the imaging side. The fourth light emitting surface S42 is a convex surface, and the fourth light emitting surface S42 is formed by being convex from the image source side to the imaging side. Among them, the first sub-lens 2441 includes a fourth light incident surface S41 and a first connecting surface S43 which are arranged in opposite directions. The first connecting surface S43 is a concave surface, and the first connecting surface S43 is formed by being concave from the imaging side to the image source side. The second sub-lens 2442 includes a second connecting surface S44 and a fourth light emitting surface S42 which are arranged in opposite directions. The second connecting surface S44 is connected to the first connecting surface S43. The second connecting surface S44 is a convex surface, and the second connecting surface S44 is formed by being convex from the image source side to the imaging side. It should be noted that the first connection surface S43 and the second connection surface S44 are adapted in size and shape. Figure 1 The first connecting surface S43 and the second connecting surface S44 shown overlap each other.

[0030] The fifth lens 245 includes a fifth light incident surface S51 and a fifth light emitting surface S52 which are arranged opposite to each other, the fifth light incident surface S51 is located between the fourth light emitting surface S42 and the fifth light emitting surface S52, the fifth light incident surface S51 can be a plane, the fifth light emitting surface S52 is a convex surface, and the fifth light emitting surface S52 is formed by convexly extending from the image source side toward the imaging side. It should be noted that the structure of the fifth light incident surface S51 is not limited to this, for example, the fifth light incident surface S51 can also be a concave surface or a convex surface.

[0031] Among them, the fifth light emitting surface S52 and the fourth light emitting surface S42 are both spherical structures, and the distance between the fifth light emitting surface S52 and the fourth light emitting surface S42 is less than 0.8 mm, for example, the distance between the fifth light emitting surface S52 and the fourth light emitting surface S42 can be 0.7 mm, 0.5 mm or 0.2 mm, etc. The distance between the fifth light emitting surface S52 and the fourth light emitting surface S42 is the distance from the spherical vertex of the fifth light emitting surface S52 to the spherical vertex of the fourth light emitting surface S42.

[0032] like Figure 1 The projector 200 shown satisfies: TTL<12mm, where TTL (Total Track Length) is the total optical length of the projector. For example, TTL can be 10mm, 10.5mm, 11mm or 11.5mm, etc. The projector 200 that satisfies the above conditions can control the size of the projection lens as a whole, which is conducive to miniaturization of the projection lens 200. For example, the total optical length of the projector can be 10.6mm, and the size of the lens in the related art is 40mm×18mm×7mm. The projector that satisfies the above conditions greatly reduces the size of the entire projector compared to the lens in the related art.

[0033] The thickness T1 of the first lens 241 satisfies 1.8 mm≤T1≤2.6 mm. For example, the thickness of the first lens 241 may be 1.8 mm, or 2.0 mm, or 2.4 mm, or 2.6 mm, wherein the thickness of the first lens 241 refers to the central thickness of the first lens 241 .

[0034] The thickness T2 of the second lens 242 satisfies 0.8 mm≤T2≤1.8 mm. For example, the thickness of the second lens 242 may be 0.8 mm, or 1.0 mm, or 1.5 mm, or 1.8 mm, where the thickness of the second lens 242 refers to the central thickness of the second lens 242 .

[0035] The thickness T3 of the third lens 243 satisfies 0.45 mm≤T2≤0.85 mm. For example, the thickness of the third lens 243 may be 0.45 mm, or 0.5 mm, or 0.6 mm, or 0.85 mm, where the thickness of the third lens 243 refers to the central thickness of the third lens 243 .

[0036] The thickness T4 of the fourth lens 244 satisfies 2.2 mm ≤ T3 ≤ 3.25 mm, for example, the thickness of the fourth lens 244 may be 2.2 mm, or 2.5 mm, or 3.0 mm, or 3.25 mm, wherein the thickness of the fourth lens 244 refers to the central thickness of the fourth lens 244. The thickness T41 of the first sub-lens 2441 satisfies 0.4 mm ≤ T41 ≤ 0.85 mm, for example, the thickness of the first sub-lens 2441 may be 0.4 mm, 0.5 mm, 0.8 mm, or 0.85 mm, and the thickness of the first sub-lens 2441 refers to the central thickness of the first sub-lens 2441; the thickness T42 of the second sub-lens 2442 satisfies 1.8 mm ≤ T42 ≤ 2.4 mm, for example, the thickness T42 of the second sub-lens 2442 may be 1.8 mm, 2.0 mm, or 2.4 mm, and the thickness of the second sub-lens 2442 refers to the central thickness of the second sub-lens 2442.

[0037] The thickness T5 of the fifth lens 245 satisfies 0.6 mm≤T4≤1.4 mm. For example, the thickness of the fifth lens 245 may be 0.6 mm, or 1.0 mm, or 1.4 mm, where the thickness of the fifth lens 245 refers to the central thickness of the fifth lens 245 .

[0038] The embodiment of the present application can effectively control the overall size of the projection optical machine 200 by reasonably setting the thickness between each lens.

[0039] like Figure 1 The projector 200 shown also satisfies: tan(FOV / 2) / TTL>0.021mm-1, 25°≤FOV≤32°, where FOV is the diagonal field of view of the projector 200, and f is the focal length of the projector 200. The projector 200 that meets the above conditions can obtain a larger field of view to meet the requirements of a large depth recognition range. The exit pupil diameter of the projector 200 is 3.5mm-6mm, and the maximum optical diameter is 5mm-7.2mm.

[0040] like Figure 1 The projection optical machine 200 shown also satisfies: 5.4mm≤f≤7.6mm, 6.4mm≤f1≤11mm, and 1.05<f1 / f<6; 5.8mm≤f2≤9.1mm, and 0.85<f2 / f<1.3; -6.4mm≤f3≤-3.1mm, and -1<f3 / f<-0.6; -200mm≤f4≤-40mm, and -25<f4 / f<-6; 8≤f5≤16, and 1.3<f5 / f<2.3. Wherein, f is the focal length of the projection optical machine, f1 is the focal length of the first lens 241, f2 is the focal length of the second lens 242, f3 is the focal length of the third lens 243, f4 is the focal length of the fourth lens 244, and f5 is the focal length of the fifth lens 245.

[0041] The fourth lens 244 satisfies: -7mm≤f41≤-2mm, and -1.4<f41 / f<-0.4; 2.8mm≤f42≤7.8mm, and 0.36<f42 / f<1.2. Where f41 is the focal length of the first sub-lens 2441, and f42 is the focal length of the second sub-lens 2442.

[0042] In the embodiment of the present application, the refractive index of the first lens 241 may be between 1.72 and 1.92, and the Abbe number of the first lens 241 may be between 36 and 54. The refractive index of the second lens 242 may be between 1.72 and 1.92, and the Abbe number of the second lens 242 may be between 36 and 54. The refractive index of the third lens 243 may be between 1.52 and 1.71, and the Abbe number of the third lens 243 may be between 32 and 50. The refractive index of the first sub-lens 2441 in the fourth lens 244 may be between 1.76 and 1.94, and the Abbe number of the first sub-lens 2441 may be between 17 and 39, and the refractive index of the second sub-lens 2442 in the fourth lens 244 may be between 1.78 and 1.94, and the Abbe number of the second sub-lens 2442 may be between 28 and 46. The refractive index of the fifth lens element 245 may be between 1.78 and 1.94, and the Abbe number of the fifth lens element 245 may be between 19 and 44.

[0043] To further explain Figure 1 The imaging effect of the projection optical machine 200 shown in the figure, the parameters of the lens of the embodiment of the present application are shown in the following Table 1:

[0044]

[0045] Among them, the diagonal field of view FOV of the projection lens 200 with parameters shown in Table 1 is 28°, the horizontal and vertical field of view ratio is 4:3, the total optical length TTL of the lens 240 is 10.6mm, the focal length f of the lens 240 is 6.3mm, the maximum optical aperture is 6.0mm, and the exit pupil aperture is 5.6mm.

[0046] The focal length f1 of the first lens 241 is 7.2 mm, the focal length f2 of the second lens 242 is 3.4 mm, the focal length f3 of the third lens 243 is -5.3 mm, the focal length f4 of the fourth lens 244 is -148 mm, the focal length f41 of the first sub-lens 2441 of the fourth lens 244 is -3.1 mm, the focal length f42 of the second sub-lens 2442 of the fourth lens 244 is 4.1 mm, and the focal length f5 of the fifth lens 245 is 10.4 mm. For other parameters (such as surface shape, radius of curvature, thickness, etc.), please refer to Table 1.

[0047] Please refer to Figures 2 to 5 , Figure 2 for Figure 1 The modulation transfer function diagram of the lens in the projection optical machine shown in the figure, Figure 3 for Figure 1 The field curvature diagram of the lens in the projection optical machine shown, Figure 4 for Figure 1 The distortion curve of the lens in the projection optical machine shown in the figure is Figure 5 for Figure 1 The defocus curve of the lens in the projection optical machine shown. Figure 2 , Figure 3 , Figure 4 and Figure 5 1 and 2 show the relevant parameter diagrams of the lens 240 having the parameters shown in Table 1. Among them, the modulation transfer function (MTF) refers to the relationship between the modulation degree and the number of line pairs per millimeter in the image, which can be used to evaluate the imaging quality of the lens, and can be reflected in the ability of the imaging to restore the details of the original object; the field curvature diagram can show the curvature and warping of the imaging surface of the lens; the distortion diagram can show the degree of deformation of the imaging picture of the lens; and the defocus curve can show the focal depth information of the lens.

[0048] from Figure 2 It can be seen from the modulation transfer function diagram shown that the MTF curves of each field of view have almost the same changing trend, and the MTF curves have no zero points from high frequency to low frequency, and the information is well preserved and can be restored into a clear image, indicating that the lens 240 of the embodiment of the present application has good resolution and resolution capability. Figure 3 It can be seen from the field curvature diagram that the values ​​of each curve deviate from the center position slightly and the change trend is smooth without sudden changes, indicating that the curvature and warping of the imaging surface of the lens 240 of the embodiment of the present application are relatively small, and the field curvature is well corrected. Figure 4 It can be seen from the distortion diagram that the optical distortion of the lens 240 of the embodiment of the present application is controlled within the range of 2.00%, indicating that the degree of deformation of the imaging image of the lens 240 of the embodiment of the present application is relatively small. Figure 5 It can be seen from the defocus curve diagram shown that the peak values ​​of almost all curves are near the zero offset vertical axis, indicating that the defocus characteristic of lens 240 is excellent, and a larger effective focal depth value range can be obtained, and the peak values ​​of all defocus characteristic curves are in a higher value area, and the imaging contrast is excellent.

[0049] It can be understood that the imaging quality of the embodiments of the present application is far higher than the Nyquist sampling evaluation of the system, the distortion and field curvature are limited to a range far smaller than that which cannot be detected by the human eye, and the assembly and debugging sensitivity of the system is weaker than the accuracy commonly used in current production, which is convenient for mass production process.

[0050] Please continue reading Figure 1The projection optical machine 200 of the embodiment of the present application may also include an aperture 260. The function of the aperture 260 is to accurately adjust the amount of light passing through. In order to take a clear picture in a dark scene, a lens with a larger light flux is required. Therefore, by setting the aperture 260, it is helpful to control the incident angle of the effective light signal reaching the lens 240. The aperture 260 is set on the side of the fifth lens 245 away from the fourth lens 244. Moreover, the distance between the aperture 260 and the fifth lens 245 is greater than 0.6mm and less than 5mm. For example, the distance between the aperture 260 and the fifth lens 245 can be 0.6mm, 1.0mm, 3mm, 5mm or other numerical distances. Among them, the distance between the aperture 260 and the fifth lens 245 refers to the distance from the aperture 260 to the preset position in the fifth light-emitting surface S52 of the fifth lens 245. The preset position can be a pre-set position, for example, the preset position can be the center point of the fifth light-emitting surface S52, or it can be other fixed points. The fifth lens 245 modulates the light beam and limits it through the aperture 260, and emits it in the form of parallel light with a specific beam diameter. Different positions on the display 220 correspond to different fields of view emitted by the projection light engine 200; that is, the light emitted by different light sources is emitted through the aperture 260 as parallel light with corresponding field angles.

[0051] The aperture 260 includes a blocking area and a light-transmitting area. The blocking area is arranged around the periphery of the light-transmitting area. The light-transmitting area can facilitate the aperture 260 to adjust the effective light signal passing through the lens 240. The light-transmitting area is a circular structure, and the light-transmitting area satisfies: 3.5mm≤D≤6mm, where D is the aperture of the light-transmitting area. For example, the light-transmitting area can be a light-transmitting circular hole, and the aperture of the circular hole can be 3.5mm, 4.0mm, 5.0mm, 6.0mm or other values. Of course, the light-transmitting area can also be other structures, such as the light-transmitting area can be a rectangular structure, a trapezoidal structure, etc. The structural surface of the aperture 260 can be processed into a matte surface, which can prevent light from being reflected or refracted on the structural surface of the aperture 260, thereby preventing other light from being mixed into the transmitted light signal passing through the lens 240.

[0052] The present application also provides a near-eye display system, such as Figure 6 As shown, Figure 6 The schematic diagram of the structure of the near-eye display system provided in the embodiment of the present application. The near-eye display system 20 may include the projection optical machine 200 (or the projection optical machine 400) as described above, and the waveguide element 600, which is arranged on the side of the lens 240 away from the display 220. Figure 1As shown, the display 220 has pixels, each of which can emit effective light signals at different emission angles. The effective light signals may include image information. The lens can receive effective light signals at different emission angles and modulate the effective light signals so that the effective light signal generated by a pixel forms parallel light beams with different emission angles after passing through the lens 230.

[0053] It can be understood that the lens 240 can be arranged between the display 220 and the waveguide element 600, and the lens 240 is located on the side of the output light of the display 220. The lens 240 can modulate the effective light signal emitted by the display 220, so that all the effective light signals entering the lens 240 are modulated into a specific light signal state output, wherein the light signal entering the lens 240 is a light beam with a certain divergence angle emitted by an array composed of pixel points at different positions on the light-emitting surface of the display 220, and the light signal output after passing through the lens 240 is a parallel light beam that overlaps at the position of the exit pupil outside the lens 220, and different pixel points correspond to different exit angles. The set of different exit angles corresponding to all pixel points is the field of view of the near-eye display system composed of the display 220 and the lens 240. The waveguide element 600 can convert the light signal emitted by the lens 240 into a virtual image after coupling in, internal total reflection propagation, and coupling out, and transmit it to the human eye, so that the human eye can see the virtual image.

[0054] It should be noted that Figure 6 The positional relationship between the projection optical machine 200 and the waveguide element 600 is only exemplary. Figure 6 The projection optical machine 200 and the waveguide element 600 are not limited to being arranged in parallel, and may be arranged at a certain angle, such as 45 degrees, 60 degrees or other angle values.

[0055] The lens, projection optical machine and near-eye display system provided in the embodiments of the present application are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the present application. At the same time, for those skilled in the art, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A lens, characterized in that: The lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens arranged in sequence along the optical axis direction, wherein the first lens is used to converge the effective light signal emitted by the display to form a first transmission light signal, the second lens is used to converge the first transmission light signal to form a second transmission light signal, the third lens is used to disperse the second transmission light signal to form a third transmission light signal, the fourth lens is used to disperse the third transmission light signal to form a fourth transmission light signal, the fifth lens is used to converge the fourth transmission light signal to form a fifth transmission light signal, and the lens has 5 lenses with optical power; The lens satisfies: tan(FOV / 2) / TTL>0.021mm -1 , 25°≤FOV≤32°, where FOV is the diagonal field of view of the lens; the lens satisfies: 5.4mm≤f≤7.6mm, 6.4mm≤f1≤11mm, and 1.05<f1 / f<6; 5.8mm≤f2≤9.1mm, and 0.85<f2 / f<1.3; -6.4mm≤f3≤-3.1mm, and -1<f3 / f<-0.6; -200mm≤f4≤-40mm, and -25<f4 / f<-6; 8≤f5≤16, and 1.3<f5 / f<2.3; where f is the focal length of the lens, f1 is the focal length of the first lens, f2 is the focal length of the second lens, f3 is the focal length of the third lens, f4 is the focal length of the fourth lens, and f5 is the focal length of the fifth lens.

2. The lens according to claim 1, characterized in that: The first lens is a positive power lens, the second lens is a positive power lens, the third lens is a negative power lens, the fourth lens is a cemented lens and the combined power of the cemented lens is negative, and the fifth lens is a positive power lens.

3. The lens according to claim 2, characterized in that: The fourth lens includes a first sub-lens and a second sub-lens glued together, the first sub-lens is located between the second sub-lens and the second lens and is a negative power lens, the second sub-lens is located between the first sub-lens and the fifth lens and is a positive power lens.

4. The lens according to claim 3, characterized in that: The first sub-lens comprises an incident surface and a first bonding surface which are arranged opposite to each other, the incident surface faces the third lens and is a concave surface, and the bonding surface is a concave surface; The second sub-lens comprises a second bonding surface and an exit surface which are arranged opposite to each other, the second bonding surface is connected to the first bonding surface, the second bonding surface is a convex surface and the shape of the second bonding surface matches the shape of the first bonding surface, the exit surface faces the fifth lens, and the exit surface is a convex surface; The third transmitted light signal is incident from the incident surface, passes through the first gluing surface and the second gluing surface in sequence, and is emitted from the exit surface to form the fourth transmitted light signal.

5. The lens according to any one of claims 1 to 4, characterized in that: The first lens comprises a first light incident surface and a first light emitting surface which are arranged opposite to each other, the first light emitting surface faces the second lens, the first light incident surface is a concave surface, and the first light emitting surface is a convex surface; The second lens comprises a second light incident surface and a second light emitting surface which are arranged opposite to each other, the second light incident surface is located between the first light emitting surface and the second light emitting surface, the second light incident surface is a convex surface, and the second light emitting surface is a concave surface, a convex surface or a flat surface; The third lens comprises a third light incident surface and a third light emitting surface which are arranged opposite to each other, the third light incident surface is located between the second light emitting surface and the third light emitting surface, the third light incident surface is a concave surface, and the third light emitting surface is a concave surface or a convex surface; The fifth lens includes a fourth light incident surface and a fourth light emitting surface arranged opposite to each other, the fourth light incident surface is located between the fourth lens and the fourth light emitting surface, the fourth light incident surface is a convex surface, a concave surface or a plane, and the fourth light emitting surface is a convex surface.

6. The lens according to claim 5, characterized in that: The curvature of the first light emitting surface is greater than the curvature of the first light incident surface.

7. The lens according to any one of claims 1 to 4, characterized in that: The total optical length of the lens is less than 12 mm.

8. The lens according to claim 7, characterized in that: The maximum optical aperture of the lens is 5mm-7.2mm, and the exit pupil aperture of the lens is 3.5mm-6mm.

9. The lens according to any one of claims 1 to 4, characterized in that: The total optical length of the lens is less than 12 mm, and the lens meets the following requirements: 1.8 mm ≤ T1 ≤ 2.6 mm, 0.8 mm ≤ T2 ≤ 1.8 mm, 0.45 mm ≤ T3 ≤ 0.85 mm, 2.2 mm ≤ T4 ≤ 3.25 mm, 0.6 mm ≤ T5 ≤ 1.4 mm; Wherein, T1 is the center thickness of the first lens, T2 is the center thickness of the second lens, T3 is the center thickness of the third lens, T4 is the center thickness of the fourth lens, and T5 is the center thickness of the fifth lens.

10. The lens according to claim 9, characterized in that: The distance between the first lens and the second lens is less than 1 mm, the distance between the second lens and the third lens is less than 0.4 mm, and the distance between the fourth lens and the fifth lens is less than 0.8 mm.

11. A projection optical machine, characterized in that: The invention comprises a lens and a display, wherein the lens is the lens according to any one of claims 1 to 10, the display is used for emitting an effective light signal, and the display is arranged on one side of the lens and adjacent to the first lens so that the effective light signal can be emitted into the first lens.

12. The projection optical machine according to claim 11, characterized in that: The projection optical machine also includes an aperture, which is arranged on the side of the fifth lens away from the fourth lens and coaxially with the lens, and the distance between the aperture and the lens is greater than 0.6 mm and less than 5 mm. The aperture is used to modulate the fifth transmitted light signal so that the transmitted light signals passing through the aperture are parallel to each other.

13. The projection optical machine according to claim 12, characterized in that: The aperture includes a blocking area and a light-transmitting area. The blocking area is arranged around the periphery of the light-transmitting area. The light-transmitting area is a circular structure. The light-transmitting area satisfies: 3.5mm≤D≤6mm, where D is the aperture of the light-transmitting area.

14. A near-eye display system, characterized in that: include: A display, wherein pixels of the display emit effective light signals with different emission angles, and the effective light signals include image information; A lens, arranged at one side of the display, for receiving the effective light signal and modulating the effective light signal so that the effective light signal generated by one pixel forms parallel light beams with different exit angles after passing through the lens, wherein the lens is the lens as claimed in any one of claims 1 to 10; A waveguide element is arranged on a side of the lens away from the display, and the waveguide element is used to receive the parallel light beams and convert the parallel light beams into a virtual image.

15. The near-eye display system according to claim 14, characterized in that: The first lens is arranged adjacent to the display so that the effective light signal generated by each pixel point can be incident on the first lens, the first lens is used to converge the effective light signal generated by each pixel point to form a plurality of first transmitted light signals with different exit angles, the second lens is used to converge the plurality of first transmitted light signals to form a plurality of second transmitted light signals with different exit angles, the third lens is used to disperse the plurality of second transmitted light signals to form a plurality of third transmitted light signals with different exit angles, the fourth lens is used to disperse the third transmitted light signal to form a plurality of fourth transmitted light signals with different exit angles, the fifth lens is used to converge the fourth transmitted light signal to form a plurality of fifth transmitted light signals with different exit angles, and the plurality of fifth transmitted light signals corresponding to one pixel point are parallel to each other.

16. The near-eye display system according to claim 14, characterized in that: The total optical length of the lens is less than 12 mm, the maximum optical aperture of the lens is 5 mm-7.2 mm, and the exit pupil diameter of the lens is 3.5 mm-6 mm.

17. The near-eye display system according to claim 16, characterized in that: The lens meets the following requirements: 1.8mm≤T1≤2.6mm, 0.8mm≤T2≤1.8mm, 0.45mm≤T3≤0.85mm, 2.2mm≤T4≤3.25mm, 0.6mm≤T5≤1.4mm; Wherein, T1 is the center thickness of the first lens, T2 is the center thickness of the second lens, T3 is the center thickness of the third lens, T4 is the center thickness of the fourth lens, and T5 is the center thickness of the fifth lens.

18. The near-eye display system according to claim 17, characterized in that: The distance between the display and the first lens is less than 4 mm, the distance between the first lens and the second lens is less than 1 mm, the distance between the second lens and the third lens is less than 0.4 mm, and the distance between the fourth lens and the fifth lens is less than 0.8 mm.

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