CN112162382A

CN112162382A - Lens, projection optical machine and near-to-eye display system

Info

Publication number: CN112162382A
Application number: CN202011097909.5A
Authority: CN
Inventors: 郑光
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2020-10-14
Filing date: 2020-10-14
Publication date: 2021-01-01

Abstract

The embodiment of the application provides a lens, a projection optical machine and a near-eye display system, the lens can be applied to the projection optical machine, the projection optical machine can be applied to the near-eye display system, the lens comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens which are sequentially arranged along an optical axis direction, the first lens is used for converging effective optical signals emitted by a display to form first transmission light signals, the second lens is used for converging the first transmission light signals to form second transmission light signals, the third lens is used for dispersing the second transmission light signals to form third transmission light signals, the fourth lens is used for dispersing the third transmission light signals to form fourth transmission light signals, and the fifth lens is used for converging the fourth transmission light signals to form fifth transmission light signals. The lens of the embodiment of the application can modulate the effective light signal emitted by the display to reduce the aberration.

Description

Lens, projection optical machine and near-to-eye display system

Technical Field

The application relates to the technical field of display projection, in particular to a lens, a projection optical machine and a near-to-eye display system.

Background

With the continuous development of augmented reality technology, head-mounted augmented reality devices such as smart glasses or smart masks are widely accepted and applied by users.

Augmented reality equipment can include projector and camera usually, and the projector can generate virtual image, and the light of virtual image and the light of real environment can shoot into simultaneously and wear the user pupil of augmented reality equipment for the user who wears augmented reality equipment not only can see real thing, can also see virtual image.

Disclosure of Invention

The embodiment of the application provides a lens, a projection optical machine and a near-to-eye display system, wherein the lens can be applied to the projection optical machine so as to modulate an effective optical signal emitted by the projection optical machine.

The embodiment of the application provides a lens, include along optical axis direction arrange first lens, second lens, third lens, fourth lens and the fifth lens that sets up in proper order, first lens is used for converging the effective light signal that the display was launched in order to form first transmitted light signal, the second lens is used for converging first transmitted light signal is in order to form second transmitted light signal, the third lens is used for the dispersion second transmitted light signal is in order to form third transmitted light signal, the fourth lens is used for the dispersion third transmitted light signal is in order to form fourth transmitted light signal, the fifth lens is used for converging fourth transmitted light signal is in order to form fifth transmitted light signal.

The embodiment of the application provides a projection optical machine, including camera lens and display, the camera lens be like the above application embodiment the camera lens, the display is used for launching effective light signal, the display sets up one side of camera lens and with first lens is adjacent so that effective light signal can penetrate into first lens.

An embodiment of the present application provides a near-to-eye display system, including:

a display, pixel points of which emit effective optical signals having different emission angles, the effective optical signals including image information;

the lens is arranged on one side of the display and used for receiving the effective optical signal and modulating the effective optical signal so as to enable the effective optical signal generated by one pixel point to form parallel light beams with different emergent angles after passing through the lens;

and the waveguide element is arranged on one side of the lens, which is far away from the display, and is used for receiving the parallel light beams and converting the parallel light beams into a virtual image.

The lens of this application embodiment includes first lens, second lens, third lens, fourth lens and the fifth lens of arranging in proper order along the optical axis direction, and the effective light signal that the display was launched passes through five lenses in proper order, and five lenses can modulate effective light signal in order to reduce the aberration.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings used in the description of the embodiments will be briefly introduced below. It is obvious that the drawings in the following description are only some embodiments of the application, and that for a person skilled in the art, other drawings can be derived from them without inventive effort.

Fig. 1 is a first structural view of a projection light engine according to an embodiment of the present disclosure.

FIG. 2 is a diagram of a modulation transfer function of a lens of the optical projection engine shown in FIG. 1.

Fig. 3 is a field curvature diagram of a lens in the optical projection engine shown in fig. 1.

FIG. 4 is a diagram illustrating a distortion curve of a lens of the optical projection engine shown in FIG. 1.

FIG. 5 is a defocus graph of the lens of the optical projection engine shown in FIG. 1.

Fig. 6 is a schematic structural diagram of a near-eye display system according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The embodiment of the application provides a projection ray apparatus, which is used for generating a virtual image. As shown in fig. 1, fig. 1 is a first structural view of a projection light engine according to an embodiment of the present disclosure. The projector 200 includes a display 220 and a lens 240, the lens 240 is disposed on one side of the display 220, the display 220 can emit a light signal, wherein the light signal capable of generating a virtual image is an effective light signal, the effective light signal can transmit through the lens 240, and 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 order from an image source side to an image side in an optical axis direction (or a light transmitting direction in which a virtual image is generated), the first lens 241 being disposed adjacent to the display 220. It is 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 order from the image source side to the image side.

The first lens 241 may 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 may receive and converge the first transmitted light signal to form a second transmitted light signal, the third lens 243 may receive and disperse the second transmitted light signal to form a third transmitted light signal, the fourth lens 244 may receive and disperse the third transmitted light signal to form a fourth transmitted light signal, and the fifth lens 245 may 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 optical signal, and the effective optical signal may form a first transmitted optical signal after passing through the first lens 241; the second lens 242 may be a positive power lens, and 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, and has a diverging effect on the second transmitted light signal, 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 power of the cemented lens is a negative value, the fourth lens 244 has a diverging effect on the third transmitted light signal, 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 chromatic aberration; the fifth lens 245 is a positive power lens, and has a converging effect on the fourth transmission light signal, and the fourth transmission light signal can form a fifth transmission light signal after passing through the fifth lens 245.

The effective optical signals emitted by the display according to the embodiment of the application can sequentially pass through the first lens 241, the second lens 242, the third lens 243, the fourth lens 244 and the fifth lens 245, and the five lenses can modulate the effective optical signals to reduce aberration, so that the imaging effect of the virtual image projected by the projection light machine 200 is improved.

With continued reference to fig. 1, the fourth lens 244 may be formed by gluing two single-piece lenses. For example, the fourth lens 244 may 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 such that one surface of the first sub-lens 2441 and one surface of the second sub-lens 2442 may be glued to each other. The first sub-lens 2441 is positioned between the second sub-lens 2442 and the third lens 243, and the first sub-lens 2441 is a negative power lens that has a diverging 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 power lens having a converging effect on the optical signal transmitted through the first sub-lens 2441.

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), the luminance of the Micro OLED is less than 5000 nits (nits) under the operating power condition, and the luminance of the LCD is less than 15000 nits. Nits (nits) is a measure of brightness, which is the human perception of light intensity and can be used to indicate the brightness of a picture. The display 220 in the embodiment of the present application may also be a Micro Light Emitting Diode (Micro-LED) display, for example, a green Micro-LED, or other single-color Micro-LEDs or white Light multi-color Micro-LEDs. Compared with the Micro-OLED and the LCD, the brightness of the Micro-LED can reach 2000000 nits, which is far higher than that of the Micro-OLED and the LCD. In addition, the Micro-LED is a self-luminous light source, so that the projection system matched with the Micro-LED has better contrast and better display delay.

The effective light emitting area of display 220 has a diagonal dimension of 0.11-0.15 inches and an effective light emitting area aspect ratio of 4: 3. In other embodiments, or the display 220 may have an effective light emitting area diagonal dimension of 0.17 inches to 0.21 inches, and an effective light emitting area aspect ratio of 16: 9. Wherein a glass cover plate is disposed outside the active light emitting surface of the display 220, and the glass cover plate can exist in a separate form or be integrally packaged in the display 220. The thickness range of the glass cover plate is 0.3mm-0.8 mm.

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 camera lens 240, five lenses of this application embodiment all adopt the glass material to make, and for the lens that the plastics material was made, the thermal stability of the lens that the glass material was made is better, is heated and is difficult to produce deformation. First lens 241, second lens 242, first sub lens 2441, second sub lens 2442 and fifth lens 245 of this application embodiment are spherical lens, adopt the scheme of glass sphere to carry out small-size optical system design, when can guarantee the optical system stability of temperature variation on a large scale, realize littleer preparation and assembly cost.

As shown in fig. 1, the first lens 241 includes a first light incident surface S11 and a first light emitting surface S12 that are opposite to each other, the first light emitting surface S12 is disposed near 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 image forming side. The first light emitting surface S12 is convex, and the first light emitting surface S12 is formed convexly from the image source side toward the image forming side. The curvature of the first light emitting surface S12 is greater than that of the first light incident surface S11, for example, the radius of curvature of the first light incident surface S11 may be 7.5mm, and the radius of curvature of the first light emitting surface S12 may be 4.0 mm. In the embodiment of the 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 3.5 mm. The first light incident surface S11 is a spherical structure, and the distance between the first light incident surface S11 and the display 220 is the distance from the spherical vertex of the first light incident surface S11 to the light emitting surface of the display 220. In 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 opposite to each other, 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 to protrude from the image forming side toward the image source side. The second light emitting surface S22 is convex, and the second light emitting surface S22 is formed convexly from the image source side toward the image forming 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 may also be a concave surface or a plane surface. The second light incident surface S21 and the first light emitting surface S12 are spherical structures, and a distance between the second light incident surface S21 and the first light emitting surface S12 is less than 1mm, for example, may be 0.5mm, 0.8mm, or 0.9 mm. The distance between the second light incident surface S21 and the first light emitting surface S12 is the distance from the spherical vertex of the second light incident surface S21 to the spherical vertex of the first light emitting surface S12.

The third lens element 243 includes a third light incident surface S31 and a third light emitting surface S32 that are opposite to each other, 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 concave, and the third light incident surface S31 is formed by being concave from the image source side toward the image forming side. The third light emitting surface S32 is concave, and the third light emitting surface S32 is formed concavely from the image source side toward the image forming side. It should be noted that the structure of the second light emitting surface S32 is not limited to this, for example, the third light emitting surface S32 may also be convex. The third light incident surface S31 and the second light emitting surface S22 are spherical structures, and a distance between the third light incident surface S31 and the second light emitting surface S22 is less than 0.4mm, for example, a distance between the third light incident surface S31 and the second light emitting surface S22 may be 0.1mm, 0.2mm, 0.3mm, or other data. The distance between the third light incident surface S31 and the second light emitting surface S22 is 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 other embodiments, a distance between the third light incident surface S31 and the second light emitting surface S22 is less than 0.2 mm.

The fourth lens 244 includes a fourth light incident surface S41 and a fourth light emitting surface S42 that are opposite to each other, 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 concave, and the fourth light incident surface S41 is formed by being concave from the image source side toward the image forming side. The fourth light emitting surface S42 is convex, and the fourth light emitting surface S42 is formed convexly from the image source side toward the image forming side. The first sub-lens 2441 includes a fourth light incident surface S41 and a first connecting surface S43, which are opposite to each other, the first connecting surface S43 is a concave surface, and the first connecting surface S43 is concavely formed from the imaging side to the image source side. The second sub-lens 2442 includes a second connection surface S44 and a fourth light emitting surface S42, which are opposite to each other, the second connection surface S44 is connected to the first connection surface S43, the second connection surface S44 is convex, and the second connection surface S44 is formed to protrude from the image source side toward the image forming side. It should be noted that the first connection surface S43 and the second connection surface S44 are matched in size and shape, and the first connection surface S43 and the second connection surface S44 shown in fig. 1 overlap each other.

The fifth lens 245 includes a fifth light incident surface S51 and a fifth light emitting surface S52 that are 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 to protrude from the image source side toward the image forming side. The structure of the fifth light incident surface S51 is not limited to this, and for example, the fifth light incident surface S51 may also be a concave surface or a convex surface.

The fifth light emitting surface S52 and the fourth light emitting surface S42 are both spherical structures, and a distance between the fifth light emitting surface S52 and the fourth light emitting surface S42 is less than 0.8mm, for example, a distance between the fifth light emitting surface S52 and the fourth light emitting surface S42 may be 0.7mm, 0.5mm or 0.2 mm. 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.

The projector engine 200 shown in FIG. 1 satisfies: TTL < 12mm, where TTL (Total Track Length) is the total optical length of the projection optical system, and TTL can be 10mm, 10.5mm, 11mm, or 11.5mm, for example. The projection light engine 200 satisfying the above conditions can control the size of the projection lens as a whole, which is advantageous for realizing the miniaturization of the projection lens 200. For example, the total optical length of the projection optical engine may be 10.6mm, and the size of the lens in the related art is 40mm × 18mm × 7mm, so that the projection optical engine satisfying the above conditions greatly reduces the overall size of the projection optical engine compared with the lens in the related art.

Wherein, the thickness T1 of the first lens 241 satisfies 1.8mm ≦ T1 ≦ 2.6mm, for example, the thickness of the first lens 241 may be 1.8mm, or 2.0mm, or 2.4mm, or 2.6mm, where the thickness of the first lens 241 refers to the center thickness of the first lens 241.

The thickness T2 of the second lens 242 satisfies 0.8mm ≦ T2 ≦ 1.8mm, for example, the thickness of the second lens 242 may be 0.8mm, or 1.0mm, or 1.5mm, or 1.8mm, where the thickness of the second lens 242 refers to the center thickness of the second lens 242.

The thickness T3 of the third lens 243 satisfies 0.45mm ≦ T2 ≦ 0.85mm, for example, the thickness of the third lens 243 may be 0.45mm, or 0.5mm, or 0.6mm, or 0.85mm, where the thickness of the third lens 243 refers to the center thickness of the third lens 243.

The thickness T4 of the fourth lens 244 satisfies 2.2mm ≦ T3 ≦ 3.25mm, for example, the thickness of the fourth lens 244 may be 2.2mm, or 2.5mm, or 3.0mm, or 3.25mm, where the thickness of the fourth lens 244 refers to the center thickness of the fourth lens 244. Wherein, the thickness T41 of the first sub-lens 2441 satisfies 0.4mm ≦ T41 ≦ 0.85mm, for example, the thickness of the first sub-lens 2441 may be 0.4mm, 0.5mm, 0.8mm, or 0.85mm, and the thickness of the first sub-lens 2441 refers to the center thickness of the first sub-lens 2441; the thickness T42 of the second sub-lens 2442 satisfies 1.8mm ≦ T42 ≦ 2.4mm, such as the thickness T42 of the second sub-lens 2442 may be 1.8mm, 2.0mm, or 2.4mm, and the thickness of the second sub-lens 2442 refers to the center thickness of the second sub-lens 2442.

The thickness T5 of the fifth lens 245 satisfies 0.6mm < T4 < 1.4mm, for example, the thickness of the fifth lens 245 may be 0.6mm, or 1.0mm, or 1.4mm, wherein the thickness of the fifth lens 245 refers to the center thickness of the fifth lens 245.

The embodiment of the application can effectively control the whole size of the projection light machine 200 by reasonably setting the thickness between the lenses.

The projector engine 200 shown in FIG. 1 further satisfies: tan (FOV/2)/TTL is more than 0.021mm-1, FOV is more than or equal to 25 degrees and less than or equal to 32 degrees, wherein the FOV is a diagonal field angle of the projection light machine 200, and f is a focal length of the projection light machine 200. The projector 200 satisfying the above conditions can obtain a larger angle of view to satisfy the requirement of a large depth recognition range. The exit pupil aperture of the projection light machine 200 is 3.5mm to 6mm, and the maximum optical aperture is 5mm to 7.2 mm.

The projector engine 200 shown in FIG. 1 further satisfies: f is more than or equal to 5.4mm and less than or equal to 7.6mm, f1 is more than or equal to 6.4mm and less than or equal to 11mm, and f1/f is more than 1.05 and less than or equal to 6; f2 is more than or equal to 5.8mm and less than or equal to 9.1mm, and f2/f is more than 0.85 and less than 1.3; f3 is more than or equal to-3.1 mm at-6.4 mm and less than-0.6 at-1 < f 3/f; f4 is more than or equal to-40 mm when the thickness is-200 mm and less than-25 and f4/f is less than-6; f5 is more than or equal to 8 and less than or equal to 16, and f5/f is more than 1.3 and less than 2.3. Where f is a focal length of the projection light engine, f1 is a focal length of the first lens 241, f2 is a focal length of the second lens 242, f3 is a focal length of the third lens 243, f4 is a focal length of the fourth lens 244, and f5 is a focal length of the fifth lens 245.

Wherein the fourth lens 244 satisfies: f41 is more than or equal to-7 mm and less than or equal to-2 mm, and f41/f is more than-1.4 and less than-0.4; f42 is more than or equal to 2.8mm and less than or equal to 7.8mm, and f42/f is more than 0.36 and less than 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.

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, the abbe number of the first sub-lens 2441 may be between 17 and 39, 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 245 may be between 1.78 and 1.94, and the abbe number of the fifth lens 245 may be between 19 and 44.

To further illustrate the imaging effect of the projector 200 shown in fig. 1, the parameters of the lens according to the embodiment of the present application are shown in table 1 below:

the field angle FOV of the projection lens 200 in the diagonal direction of the parameters shown in table 1 is 28 °, the horizontal-to-vertical field 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 5.6 mm.

The focal length f1 of the first lens 241 is 7.2mm, the focal length f2 of the second lens 242 is 3.4mm, 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 4.1mm, and the focal length f5 of the fifth lens 245 is 10.4 mm. See table 1 for the remaining parameters (such as profile, radius of curvature, thickness, etc.).

Referring to fig. 2 to 5, fig. 2 is a modulation transfer function diagram of a lens in the projection optics shown in fig. 1, fig. 3 is a field curvature diagram of the lens in the projection optics shown in fig. 1, fig. 4 is a distortion curve diagram of the lens in the projection optics shown in fig. 1, and fig. 5 is a defocus curve diagram of the lens in the projection optics shown in fig. 1. Fig. 2, 3, 4 and 5 each show a related parameter map of the lens 240 having the parameters shown in table 1. The Modulation Transfer Function (MTF) refers to a relationship between a Modulation degree and a line logarithm per millimeter in an image, and can be used for evaluating the imaging quality of a lens and can be embodied as the reduction capability of imaging on original object details; the field curvature diagram can represent the curvature and warping degree of an imaging surface of the lens; the distortion graph can represent the distortion degree of a lens imaging picture; the defocus curve may represent depth-of-focus information of the lens.

As can be seen from the modulation transfer function diagram shown in fig. 2, the MTF curves of the respective fields of view have almost the same trend, and no zero point appears on the MTF curves from high frequency to low frequency, so that the information is well preserved, and the information can be restored to a clear image, which indicates that the lens 240 according to the embodiment of the present application has good resolution and resolution. As can be seen from the field curvature diagram shown in fig. 3, the small variation trend of the numerical value of each curve deviating from the center position is smooth and has no sudden change, which indicates that the curvature and the warp of the imaging surface of the lens 240 according to the embodiment of the present application are relatively small, and the field curvature is well corrected. As can be seen from the distortion diagram shown in fig. 4, the optical distortion amount of the lens 240 of the embodiment of the present application is controlled within a range of 2.00%, which illustrates that the degree of distortion of the imaging screen of the lens 240 of the embodiment of the present application is relatively small. As can be seen from the defocus graph shown in fig. 5, the peaks of almost all the curves are near the zero-offset vertical axis, which indicates that the defocus characteristic of the lens 240 is excellent, a larger effective depth-of-focus value range can be obtained, and the peaks of all the defocus characteristic curves are in a higher value region, so that the imaging contrast is excellent.

It can be understood that the imaging quality of the embodiment of the application is much higher than the nyquist sampling evaluation of the system, the distortion and the field curvature are all limited to be much smaller than the range which can not be detected by human eyes, and the assembly and debugging sensitivity of the system is weaker than the precision commonly used in the current production, thereby facilitating the mass production process.

With reference to fig. 1, the optical projection engine 200 of the present embodiment may further include a diaphragm 260, where the diaphragm 260 is used to precisely adjust the amount of light passing through, and a lens with a larger luminous flux is required to capture a clear picture in a scene with dark light, so that the setting of the diaphragm 260 is beneficial to controlling the incident angle of the effective light signal reaching the lens 240. The diaphragm 260 is arranged on the side of the fifth lens 245 facing away from the fourth lens 244. Further, the distance between the stop 260 and the fifth lens 245 is greater than 0.6mm and less than 5mm, for example, the distance between the stop 260 and the fifth lens 245 may be 0.6mm, 1.0mm, 3mm, 5mm, or other values. The distance between the stop 260 and the fifth lens 245 is a distance from the stop 260 to a preset position in the fifth light emitting surface S52 of the fifth lens 245, and the preset position may be a preset position, for example, the preset position may be a central point of the fifth light emitting surface S52, or other fixed points. The fifth lens 245 performs beam modulation, then restricts the light by the stop 260, and emits the light as parallel light having a specific beam aperture. Different positions on the display 220 correspond to different fields of view emitted by the projector 200; i.e. the light emitted by different light emitting sources exits through the aperture 260 as parallel light at the respective corresponding field angle.

The diaphragm 260 includes a shielding region and a light transmission region, the shielding region is surrounded on the periphery of the light transmission region, and the light transmission region can facilitate the adjustment of the diaphragm 260 on the effective light signal transmitted through the lens 240. The light transmission region is of a circular structure and meets the following requirements: d is more than or equal to 3.5mm and less than or equal to 6mm, and D is the aperture of the light-transmitting area. For example, the light-transmitting region may be a light-transmitting circular hole, and the aperture of the circular hole may be 3.5mm, 4.0mm, 5.0mm, 6.0mm, or other values. Of course, the light-transmitting region may have other structures, such as a rectangular structure, a trapezoidal structure, and the like. The structured surface of the stop 260 may be treated as an extinction surface to prevent light rays from reflecting or refracting on the structured surface of the stop 260 and causing other light rays to be mixed into the transmitted light signal transmitted through the lens 240.

An embodiment of the present application further provides a near-eye display system, such as shown in fig. 6, where fig. 6 is a schematic structural diagram of the near-eye display system provided in the embodiment of the present application. The near-eye display system 20 may include the light projector 200 (which may also be the light projector 400) as described above, and a waveguide element 600, the waveguide element 600 being disposed on a side of the lens 240 facing away from the display 220. As shown in fig. 1, the display 220 has pixel points, each pixel point can emit effective optical signals with different emission angles, the effective optical signals can include image information, and the lens can receive the effective optical signals with different emission angles and modulate the effective optical signals, so that the effective optical signals generated by one pixel point form parallel light beams with different exit angles after passing through the lens 230.

It can be understood that the lens 240 may be disposed between the display 220 and the waveguide 600, the lens 240 is located on one side of the emergent light of the display 220, the lens 240 may modulate the effective light signals emitted by the display 220, so that all the effective light signals entering the lens 240 are modulated into a specific light signal state to be output, where the light signals entering the lens 240 are light beams with a certain divergence angle emitted by an array formed by pixels at different positions on the light emitting surface of the display 220, the light signals output after passing through the lens 240 are parallel light beams overlapping at the outer exit pupil position of the lens 220 and corresponding to different exit angles of different pixels, and the set of different exit angles corresponding to all the pixels is the field of view of the near-to-eye display system formed by the display 220 and the lens 240. The waveguide 600 may convert the optical signal emitted from the lens 240 into a virtual image after the optical signal is coupled in, propagated by total internal reflection, and coupled out, and transmit the virtual image to human eyes, so that the human eyes can watch the virtual image.

It should be noted that the positional relationship between the light projector 200 and the waveguide 600 in fig. 6 is only an example, and the positional relationship between the light projector 200 and the waveguide 600 in fig. 6 is not limited to a parallel arrangement, and may also be set at an inclined angle, such as 45 degrees, 60 degrees or other angle values.

The lens, the projector and the near-to-eye display system provided by the embodiment of the present application are described in detail above. The principles and implementations of the present application are described herein using specific examples, which are presented only to aid in understanding the present application. Meanwhile, for those skilled in the art, according to the idea of the present application, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present application.

Claims

1. A lens barrel is characterized by comprising a first lens, a second lens, a third lens, a fourth lens and a fifth lens which are sequentially arranged along the direction of an optical axis, wherein the first lens is used for converging an effective light signal emitted by a display to form a first transmission light signal, the second lens is used for converging the first transmission light signal to form a second transmission light signal, the third lens is used for dispersing the second transmission light signal to form a third transmission light signal, the fourth lens is used for dispersing the third transmission light signal to form a fourth transmission light signal, and the fifth lens is used for converging the fourth transmission light signal to form a fifth transmission light signal.

2. The lens barrel according to claim 1, wherein 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 a combined power of the cemented lens is a negative value, and the fifth lens is a positive power lens.

3. The lens barrel according to claim 2, wherein the fourth cemented lens includes a first sub-lens and a second sub-lens cemented to each other, the first sub-lens being located between the second sub-lens and the second lens and the first sub-lens being a negative power lens, the second sub-lens being located between the first sub-lens and the fifth sub-lens and the second sub-lens being a positive power lens.

4. The lens barrel according to claim 3, wherein the first sub-lens comprises an incident surface and a first cemented surface which are opposite to each other, the incident surface faces the third lens and is a concave surface, and the cemented surface is a concave surface;

the second sub-lens comprises a second adhesive surface and an emergent surface which are arranged in a reverse manner, the second adhesive surface is connected with the first adhesive surface, the second adhesive surface is a convex surface, the shape of the second adhesive surface is matched with that of the first adhesive surface, the emergent surface faces the fifth lens, and the emergent surface is a convex surface;

and the third optical signal enters from the incident surface, sequentially passes through the first bonding surface and the second bonding surface, and exits from the exit surface to form the fourth optical signal.

5. The lens barrel according to any one of claims 1 to 4, wherein the first lens includes a first light incident surface and a first light emitting surface that are 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 in a back-to-back manner, the second light incident surface is positioned 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 plane;

the third lens comprises a third light incident surface and a third light emitting surface which are arranged in a reverse manner, the third light incident surface is positioned 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 comprises a fourth light incident surface and a fourth light emergent surface which are arranged back to back, the fourth light incident surface is located between the fourth lens and the fourth light emergent surface, the fourth light incident surface is a convex surface, a concave surface or a plane, and the fourth light emergent surface is a convex surface.

6. The lens barrel as claimed in claim 5, wherein a curvature of the first light emitting surface is greater than a curvature of the first light incident surface.

7. A lens barrel according to any one of claims 1 to 4, wherein the total length of optical power of the lens barrel is less than 12 mm.

8. The lens barrel according to claim 7, wherein the maximum optical aperture of the lens barrel is 5mm to 7.2mm, and the exit pupil aperture of the lens barrel is 3.5mm to 6 mm.

9. The lens barrel according to claim 7, wherein the lens barrel satisfies: tan (FOV/2)/TTL >0.021mm^-1And the FOV is more than or equal to 25 degrees and less than or equal to 32 degrees, wherein the FOV is the field angle of the lens in the diagonal direction.

10. A lens barrel according to any one of claims 1 to 4, wherein the total optical length of the lens barrel is less than 12mm, and the lens barrel satisfies: t1 is more than or equal to 1.8mm and less than or equal to 2.6mm, T2 is more than or equal to 0.8mm and less than or equal to 1.8mm, T3 is more than or equal to 0.45mm and less than or equal to 0.85mm, T4 is more than or equal to 2.2mm and less than or equal to 3.25mm, and T5 is more than or equal to 0.6mm and less than or equal to 1.4 mm;

wherein T1 is a center thickness of the first lens, T2 is a center thickness of the second lens, T3 is a center thickness of the third lens, T4 is a center thickness of the fourth lens, and T5 is a center thickness of the fifth lens.

11. The lens barrel according to claim 10, wherein a distance between the first lens and the second lens is less than 1mm, a distance between the second lens and the third lens is less than 0.4mm, and a distance between the fourth lens and the fifth lens is less than 0.8 mm.

12. The lens barrel according to claim 11, wherein the lens barrel satisfies: f is more than or equal to 5.4mm and less than or equal to 7.6mm, f1 is more than or equal to 6.4mm and less than or equal to 11mm, and f1/f is more than 1.05 and less than or equal to 6; f2 is more than or equal to 5.8mm and less than or equal to 9.1mm, and f2/f is more than 0.85 and less than 1.3; f3 is more than or equal to-3.1 mm at-6.4 mm and less than-0.6 at-1 < f 3/f; f4 is more than or equal to-40 mm when the thickness is-200 mm and less than-25 and f4/f is less than-6; f5 is more than or equal to 8 and less than or equal to 16, and f5/f is more than 1.3 and less than 2.3;

wherein f is a focal length of the lens, f1 is a focal length of the first lens, f2 is a focal length of the second lens, f3 is a focal length of the third lens, f4 is a focal length of the fourth lens, and f5 is a focal length of the fifth lens.

13. A projection optical machine, comprising a lens according to any one of claims 1 to 12 and a display, wherein the display is used for emitting an effective light signal, and the display is disposed at one side of the lens and adjacent to the first lens so that the effective light signal can enter the first lens.

14. The light engine of claim 13, further comprising a diaphragm disposed on a side of the fifth lens facing away from the fourth lens and disposed coaxially with the lens, wherein a distance between the diaphragm and the lens is greater than 0.6mm and less than 5mm, and the diaphragm is configured to modulate the fifth transmission light signal such that the transmission light signals transmitted through the diaphragm are parallel to each other.

15. The optical engine of claim 14, wherein the diaphragm comprises a blocking area and a light-transmitting area, the blocking area is disposed around the periphery of the light-transmitting area, the light-transmitting area is a circular structure, and the light-transmitting area satisfies: d is more than or equal to 3.5mm and less than or equal to 6mm, and D is the aperture of the light-transmitting area.

16. A near-eye display system, comprising:

17. The near-eye display system of claim 16 wherein 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, the first lens is disposed adjacent to the display such that the effective optical signal generated by each of the pixel points can be incident on the first lens, the first lens is configured to converge the effective optical signal generated by each of the pixel points to form a first transmitted optical signal at a plurality of different exit angles, the second lens is configured to converge the plurality of first transmitted optical signals to form a second transmitted optical signal at a plurality of different exit angles, the third lens is configured to disperse the plurality of second transmitted optical signals to form a third transmitted optical signal at a plurality of different exit angles, and the fourth lens is configured to disperse the third transmitted optical signal to form a fourth transmitted optical signal at a plurality of different exit angles, the fifth lens is used for converging the fourth transmitted light signals to form a plurality of fifth transmitted light signals with different emergent angles, and the plurality of fifth transmitted light signals corresponding to one pixel point are mutually parallel.

18. The near-eye display system of claim 16 wherein the total optical length of the lens is less than 12mm, the maximum optical aperture of the lens is between 5mm and 7.2mm, and the exit pupil aperture of the lens is between 3.5mm and 6 mm.

19. The near-eye display system of claim 18 wherein the lens satisfies: t1 is more than or equal to 1.8mm and less than or equal to 2.6mm, T2 is more than or equal to 0.8mm and less than or equal to 1.8mm, T3 is more than or equal to 0.45mm and less than or equal to 0.85mm, T4 is more than or equal to 2.2mm and less than or equal to 3.25mm, and T5 is more than or equal to 0.6mm and less than or equal to 1.4 mm;

20. The near-eye display system of claim 19 wherein the distance between the display and the first lens is less than 4mm, the distance between the first lens and the second lens is less than 1mm, the distance between the second lens and the third lens is less than 0.4mm, and the distance between the fourth lens and the fifth lens is less than 0.8 mm.