Optical module and display device

Abstract

The invention discloses an optical module and a display device, the optical module comprises a lens group, the lens group comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens in sequence from an image space to an object space, and the focal power is set to be positive, negative, positive, positive and negative in sequence; the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all plastic lenses. In the head-mounted device, the light emitted by the image source sequentially passes through the lenses in the lens group to the image space for imaging, and the lenses in the lens group are plastic lenses and can realize aberration balance, so that the optical module can be light, thin and high in luminous efficiency, the overall power consumption of the head-mounted device is reduced, and the wearing comfort is improved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to an optical module and a display device. Background Art

[0002] Virtual reality technology (VR for short) allows users to have a feeling of being in a virtual world. Almost all immersive virtual reality categories use helmet displays as key equipment.

[0003] However, the eyepieces in existing VR headsets are relatively heavy, which has little impact in non-wearable areas, but in wearable areas, the heavy weight will reduce wearing comfort. In addition to the comfortable and thin feeling of wearing, the eyepieces have low light efficiency, resulting in high power consumption and high heat generation of the whole device, thus poor user experience. Summary of the invention

[0004] In view of this, an embodiment of the present invention provides an optical module and a display device to solve the problems of heavy weight and low light efficiency of the optical module in the prior art.

[0005] Therefore, an embodiment of the present invention provides an optical module, the optical module includes a lens group, the lens group includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens in order from the image side to the object side, and the optical power is set to positive, negative, positive, positive, negative in sequence;

[0006] The first lens, the second lens, the third lens, the fourth lens and the fifth lens are all plastic lenses.

[0007] In a possible implementation, the first lens is a biconvex lens, the second lens is a biconcave lens, the third lens is a biconvex lens, the fourth lens is a meniscus lens with the concave surface facing the object, and the fifth lens is a biconcave lens.

[0008] In a possible implementation manner, the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all aspherical lenses.

[0009] In a possible implementation, the optical module satisfies:

[0010] 1<(f1+f2+f3+f4+f5) / F<2; wherein F is the total effective focal length of the optical module, 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.

[0011] In a possible implementation, the optical module satisfies:

[0012] 1.2<f1 / F<1.5; -2.5<f2 / F<-2; 1.5<f3 / F<2; 0.9<f1 / f4<1.1; 3 <f2 / f5<4; 1.2<f3 / f1<1.5; -1.8<f2 / f1<-1.5; -1.5<f2 / f3<-1.

[0013] In a possible implementation, the optical module satisfies:

[0014] The eye movement range is greater than 8mm.

[0015] In a possible implementation, the optical module satisfies:

[0016] The pupil distance is greater than 15mm.

[0017] In a possible implementation, the first lens, the second lens, and the third lens form a triplet lens.

[0018] In a possible implementation manner, surfaces of the first lens, the second lens, the third lens, the fourth lens, and the fifth lens are all coated with an anti-reflection film.

[0019] On the other hand, an embodiment of the present invention further provides a display device, comprising the optical module described in the above embodiment.

[0020] The beneficial effects of the embodiments of the present invention are as follows:

[0021] The embodiment of the present invention provides an optical module and a display device, wherein the optical module includes a lens group, wherein the lens group includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens in order from the image side to the object side, and the optical focal length is set to positive, negative, positive, positive, and negative in sequence; the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all plastic straight-through lenses. In the present application, the light emitted by the image source passes through each lens in the lens group in sequence to form an image on the image side. Since the lenses in the lens group are all plastic lenses and can achieve aberration balance, the optical module can be made thinner and have high light efficiency, thereby reducing the overall power consumption of the head-mounted device and improving the wearing comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The figure shows one of the structural schematic diagrams of an optical module provided in an embodiment of the present application;

[0023] Figure 2 The figure shows a second structural schematic diagram of an optical module provided in an embodiment of the present application;

[0024] Figure 3 Shown is the MTF curve of the optical module at 10lp / mm;

[0025] Figure 4 Shown is the MTF curve of the optical module at 79lp / mm;

[0026] Figure 5 Shown is an optical field curvature diagram of an optical module;

[0027] Figure 6 The third structural schematic diagram of an optical module provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0028] The specific implementation of the optical module and the display device provided by the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0029] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0030] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0033] Figure 1 FIG. 1 shows a schematic diagram of the structure of an optical module provided by the present disclosure. Figure 1As shown, the optical module provided by the present disclosure includes a lens group and an image source in order from the image side to the object side. In some embodiments, a turning prism ( Figure 1 (not shown), the light emitted by the image source passes through the turning prism and the lens group in sequence to form an image on the image side. Figure 1 The optical path diagram of the above optical module is also shown, which adopts a reverse optical path design.

[0034] The image source in this embodiment can be a light-emitting screen such as a micro display, for example, the micro display can be implemented using technologies such as organic light emitting diode (OLED), micro light emitting diode (MicroLED), digital light processing (DLP) or liquid crystal on silicon (LCOS). The image source of this application supports the use of 4k*4k silicon-based OLED (Micro-OLED). Since Micro-OLED is self-luminous, it will be more compact in structure and smaller in size, which is conducive to miniaturization of optical modules.

[0035] The above-mentioned optical module provided by the present disclosure is applied in a VR device, and the light transmission is as follows: the image in the display screen of the VR device is transmitted and amplified through the optical module described in the embodiment of the present disclosure and then transmitted to the human eye. At this time, what is received by the human eye side through the optical module is the magnified virtual image of the display screen, that is, the light is emitted from the display screen, and after being transmitted through the optical module, what is viewed on the human eye side is an enlarged inverted virtual image.

[0036] The optical module provided by the present invention adopts a straight-through structure, and the light does not need to be turned back multiple times in the system, but is only transmitted along the same straight line. It has high optical efficiency and high resolution. It can be used on AR devices to effectively improve the user's sense of immersion and bring a better experience to the user.

[0037] In some embodiments, the optical module may further include an aperture, which is disposed on the image side of the lens group. The aperture refers to an entity that limits the light beam in an optical system, and may be the edge of a lens, a frame, or a specially arranged screen with holes. The role of the aperture can be divided into two aspects, limiting the light beam or limiting the size of the field of view (imaging range). The aperture that limits the light beam the most in an optical system is called an aperture aperture, and the aperture that limits the field of view (size) the most is called a field aperture. As can be seen from the above, both the aperture aperture and the field aperture are real objects. The general rule for determining the aperture aperture of an optical system is: looking at the aperture or the image of the aperture from the object point, the aperture aperture of the optical system is determined by the one with the smallest opening angle. If the image of a certain aperture has the smallest opening angle, then the aperture itself is the aperture aperture.

[0038] In addition, a protective glass may be provided between the lens group and the image source. The size of the protective glass may be set to be no smaller than the size of the image source. The image source may be isolated and protected by the protective glass.

[0039] In this embodiment, all lenses in the lens group are aspherical lenses. Figure 1 As shown, the lens group includes a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, and a fifth lens G5 which are arranged in sequence from the image side to the object side. The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are coaxially arranged.

[0040] An aspheric lens is an optical element whose surface shape is not a traditional spherical surface, but an aspheric design. Compared with traditional spherical lenses, it can control the refraction of light more accurately, thereby effectively correcting various aberrations and improving imaging quality. Its surface can be a parabola, hyperbola, elliptical or other aspheric geometric shapes. For example, parabolic aspheric lenses are often used in optical systems, which can converge parallel light rays to one point more accurately, reducing the problem of spot diffusion caused by the difference in refraction of edge light rays in spherical lenses. The thickness of an aspheric lens is often not uniform from the center to the edge, but changes according to a specific functional relationship based on the requirements of the optical design, so as to achieve an ideal refraction effect on light.

[0041] Aspherical lenses can achieve the same or even better imaging effects with fewer lenses due to their unique optical properties. Therefore, the use of aspherical lenses in optical systems can reduce the number of lenses, thereby reducing the overall size and weight of the lens, which is very critical for portable optical devices such as VR devices.

[0042] The embodiment of the present application uses a plastic aspheric lens. For the production of the plastic aspheric lens, the plastic optical material is melted and then injected into a special mold cavity for molding. The cost is low and aspheric lenses with complex shapes can be manufactured. It is suitable for use in cost-sensitive fields such as consumer electronics. For example, the plastic aspheric lens in the optical module of VR / AR equipment can be manufactured by the above-mentioned injection molding. The aspheric lens can provide users with a clear and comfortable virtual or augmented reality visual experience.

[0043] It should be noted that, on the image side, i.e., the side observed by the human eye, when a user uses a VR device having the above-mentioned optical module, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are arranged in sequence along the line of sight of the human eye.

[0044] Among them, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are all plastic lenses, and the five lenses form a straight-through optical structure. Since the five lenses are all made of plastic, the weight of the lens group does not exceed 20g, which can achieve a light and thin effect for the lens group, and can also achieve an optical length of less than 40mm, which is conducive to the miniaturization of the whole machine. When the lens is used in a wearable device, it can reduce the user's wearing discomfort. The optical length refers to the distance between the center point of the first lens and the image source.

[0045] Specifically, the first lens is a biconvex lens, the second lens is a biconcave lens, the third lens is a biconvex lens, the fourth lens is a meniscus lens with the concave surface facing the object, and the fifth lens is a biconcave lens.

[0046] Specifically, the surface of the lens facing the image side is the first surface, and the surface facing the object side is the second surface. The first surface of the first lens is convex, and the second surface is also convex; the first surface of the second lens is concave, and the second surface is also concave; the first surface of the third lens is convex, and the second surface is also convex; the first surface of the fourth lens is convex, and the second surface is concave; the first surface of the fifth lens is concave, and the second surface is also concave.

[0047] Specifically, the first lens G1 is set to have positive focal power, the second lens G2 is set to have negative focal power, the third lens G3 is set to have positive focal power, the fourth lens G4 is set to have positive focal power, and the fifth lens G5 is set to have negative focal power. In this embodiment, there are three positive lenses and two negative lenses, which can achieve aberration balance.

[0048] Specifically, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are all aspherical lenses. It can be seen that the lens group of this embodiment includes 5 aspherical lenses. Using 5 aspherical lenses can reduce aberrations such as vertical axis chromatic aberration and spherical aberration with very few lenses.

[0049] In some embodiments, Figure 2 As shown, the first lens G1, the second lens G2, and the third lens G3 can form a triple-cemented lens. Specifically, the first lens G1, the second lens G2, and the third lens G3 are arranged in close contact, that is, the second surface of the first lens G1 and the first surface of the second lens G2 have similar surface shapes, the second surface of the second lens G2 and the first surface of the third lens G3 have similar surface shapes, and the gaps between the first lens G1, the second lens G2, and the third lens G3 are small, generally not exceeding 0.8 mm, that is, the three lenses can be triple-cemented by appropriate adjustment, and of course, air gaps can be added, such as Figure 1 shown.

[0050] Currently, optical modules have a large number of lenses, which leads to poor assembly accuracy. The use of a triple-cemented lens in this application can simplify the assembly process and improve assembly accuracy.

[0051] In some embodiments, the surfaces of the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are all coated with an anti-reflection film. Alternatively, at least one surface of the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 is coated with an anti-reflection film.

[0052] The main function of anti-reflection film is to reduce or eliminate the reflected light from optical surfaces such as lenses, prisms, and plane mirrors, thereby increasing the light transmittance of these components and reducing or eliminating the stray light of the system.

[0053] Exemplarily, an anti-reflection film is disposed on at least one of the first surface and the second surface of the first lens G1, the first surface and the second surface of the second lens G2, the first surface and the second surface of the third lens G3, the first surface and the second surface of the fourth lens G4, and the first surface and the second surface of the fifth lens G5. The provision of the anti-reflection film can increase the transmittance of light.

[0054] The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 of this embodiment form a straight-through optical structure. Since straight-through one-shot imaging is adopted, the light efficiency is relatively high. Furthermore, an anti-reflection film is plated on the surface of each lens to further improve the one-shot light passing rate. It can be seen that the optical module of this application has a high light efficiency. When used in a display device, it can reduce the power consumption of the entire device, thereby improving the user experience.

[0055] Specifically, the above optical module satisfies: 1<(f1+f2+f3+f4+f5) / F<2; wherein F is the total effective focal length of the optical module, f1 is the focal length of the first lens G1, f2 is the focal length of the second lens G2, f3 is the focal length of the third lens G3, f4 is the focal length of the fourth lens G4, and f5 is the focal length of the fifth lens G5.

[0056] Specifically, the above optical module satisfies: 1.2<f1 / F<1.5; -2.5<f2 / F<-2; 1.5<f3 / F<2; 0.9<f1 / f4<1.1; 3<f2 / f5<4; 1.2<f3 / f1<1.5; -1.8<f2 / f1<-1.5; -1.5<f2 / f3<-1.

[0057] It should be noted that, in practical applications, the air space behind each lens can be appropriately allocated according to the optical length of the optical module, which is beneficial to the structural design of the imaging lens and facilitates lens assembly and mass production.

[0058] Specifically, the optical module satisfies: 0.2<T1 / TTL<0.5, 0.06<T2 / TTL<0.2, 0.07<T3 / TTL<0.3, 0.05<T4 / TTL<0.4, 0.08<T5 / TTL<0.3; wherein TTL is the total optical length of the optical module, T1 is the center thickness of the first lens G1, T2 is the center thickness of the second lens G2, T3 is the center thickness of the third lens G3, T4 is the center thickness of the fourth lens G4, and T5 is the center thickness of the fifth lens G5.

[0059] In an optical module, the thickness distribution of each lens is a relatively complex and critical design element, which is affected by many factors. For example, the focal length of a lens determines its ability to converge or diverge light, and the thickness is closely related to the focal length. In order to achieve a specific focal length, it is necessary to comprehensively consider the refractive index of the lens material and the surface curvature radius, which in turn affects its thickness. In an optical module, in order for the entire system to achieve the desired equivalent focal length, different lenses need to be allocated thickness according to the corresponding optical design.

[0060] Aberrations include spherical aberration, coma, astigmatism, field curvature and distortion, etc. In order to correct these aberrations, the thickness distribution of each lens also needs to be designed in a targeted manner. Taking spherical aberration correction as an example, for a spherical lens, the edge light and the center light cannot converge to the same focus after refraction, which will produce spherical aberration. This application uses aspherical lenses to improve this. By reasonably increasing or decreasing the thickness of certain lenses and changing the propagation path of light in the lens, the light can be more accurately converged to form an image after passing through the entire optical module, reducing the impact of aberrations.

[0061] During the assembly of optical modules, the thickness of the lens will also affect the convenience and accuracy of assembly. If the lens is too thin, it is easy to be damaged or installed inaccurately during assembly operations such as clamping and positioning; while a lens that is too thick may cause the overall size of the module to be too large, which does not meet the design expectations, and may also increase the cumulative error during assembly. Therefore, the thickness distribution should be considered to facilitate assembly, ensure that each lens can be accurately installed in the corresponding position of the optical module, and work together to achieve good optical functions.

[0062] In this embodiment, the thickness of each lens in the optical module is appropriately distributed, which is conducive to reducing the difficulty of the lens manufacturing process, thereby saving raw materials and reducing costs; the optical module of this embodiment is small in size and compact in structure, which is conducive to miniaturization of wearable devices.

[0063] Specifically, the above optical module satisfies: 0≤Air1 / TTL<0.1; 0≤Air2 / TTL<0.1; 0.01≤Air3 / TTL<0.5; 0.01≤Air4 / TTL<0.3; 0.01≤Air5 / TTL<0.5; wherein Air1 is the air space behind the first lens G1, Air 2 is the air space behind the second lens G2, Air3 is the air space behind the third lens G3, Air4 is the air space behind the fourth lens G4, and Air5 is the air space behind the fifth lens G5.

[0064] In this embodiment, the air gap behind each lens is appropriately allocated according to the total optical length of the optical module, which is beneficial to the structural design of the optical module, thereby facilitating module assembly and mass production. The air gap between the fifth lens and the image source is constrained according to the above, which not only ensures the feasibility of structural design and process assembly, but also greatly compresses the module length, which is beneficial to the miniaturization and mass production of the module.

[0065] Specifically, the above optical module meets the following requirements: the eye movement range is greater than 8mm. The present application adopts an optical module that corrects aberrations by means of multiple aspherical lenses, which can maintain a relatively stable imaging effect when the eye moves, and the eye movement range is larger within a reasonable range.

[0066] Specifically, the optical module meets the following requirements: the pupil distance is greater than 15 mm. The pupil of the present application is relatively large. In existing direct-through solutions for high-resolution screens, in order to achieve higher image quality, the pupil distance is generally not high, mostly 11-13 mm.

[0067] The optical module provided in this embodiment can achieve the following functions based on the above structural design constraints:

[0068] 1. It can adapt to 4K high-definition display screens, and the MTF (modulation transfer function) of each field of view does not drop by an average of no more than 0.1 at 10lp / mm. Figure 3 Shown is the MTF curve at 10lp / mm.

[0069] Figure 4 The MTF curve at 79lp / mm is shown. Compared with the existing straight-through solution, the weight can be reduced due to the use of a full plastic lens. At the same optical length level, the weight of the entire lens group does not exceed 20g. In addition, corresponding to the 4K display design, a higher frequency (79lp / mm>0.2) resolution can be achieved. Figure 4 .

[0070] 2. Imaging spot diameter <6μm.

[0071] 3. Figure 5 The optical field curvature diagram of the above optical module is shown as follows: Figure 5As shown, the overall field curvature of the system does not exceed 0.2 mm.

[0072] 4. The field of view angle FOV is greater than 63°, the optical length is less than 40mm, and the overall transmittance is greater than 70%. While achieving high image quality, it can reduce display power consumption. Compared with the pancake solution (theoretical transmittance is up to 25%), it can greatly reduce display power consumption; compared with the Fresnel direct-through solution, there is less stray light, and the utilization rate of light can be improved by coating with an anti-reflection film.

[0073] Exemplarily, the optical module is located on the light-emitting side of the display screen of the VR device, and the optical module may also include an adjustment structure for adjusting the distance between the fifth lens and the display screen. The specific structural form of the adjustment structure may be various, and this application does not limit this. Through the adjustment structure, the distance between the fifth lens and the display screen can be adapted to the degree of myopia of the human eye to obtain a better image, thereby improving the user experience.

[0074] In addition, if Figure 6 As shown, the surface shapes of the first surface and the second surface of the second lens G2 may be changed, and the surface shape of the second surface of the fourth lens G4 may be slightly adjusted to achieve the same technical effect as above.

[0075] like Figure 6 As shown, the optical module provided in this embodiment includes a lens group and an image source in order from the image side to the object side, and the lens group includes a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, and a fifth lens G5 arranged in sequence from the image side to the object side, and the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are coaxially arranged. Among them, the first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 are all plastic lenses, and the weight of the lens group does not exceed 20g, which can achieve a light and thin effect of the lens group.

[0076] The first surface of the first lens G1 is convex, and the second surface is also convex; the first surface of the second lens G2 is concave, and the second surface is also concave; the first surface of the third lens G3 is convex, and the second surface is also convex; the first surface of the fourth lens G4 is convex, and the second surface is concave; the first surface of the fifth lens G5 is concave, and the second surface is also concave.

[0077] Among them, the surface shape of the first surface of the second lens G2 is the same as the surface shape of the second surface of the first lens G1, and the surface shape of the second surface of the second lens G2 is the same as the surface shape of the first surface of the third lens G3. Therefore, the first lens G1, the second lens G2, and the third lens G3 can be cemented together to form a triple cemented lens. The triple cemented lens can simplify the assembly process and improve the assembly accuracy.

[0078] An anti-reflection film is disposed on at least one of the first surface and the second surface of the first lens G1, the first surface and the second surface of the second lens G2, the first surface and the second surface of the third lens G3, the first surface and the second surface of the fourth lens G4, and the first surface and the second surface of the fifth lens G5. The anti-reflection film can increase the light transmittance.

[0079] The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 of this embodiment form a straight-through optical structure. Since straight-through one-shot imaging is adopted, the light efficiency is relatively high. Furthermore, an anti-reflection film is plated on at least one surface of each lens, which further improves the one-shot light passing rate. Therefore, the optical module of this application has a relatively high light efficiency, and when used in a display device, it can reduce the power consumption of the entire device, thereby improving the user experience.

[0080] The first lens G1, the second lens G2, the third lens G3, the fourth lens G4, and the fifth lens G5 of this embodiment are all aspherical lenses. Based on the law of refraction, light will refract when it enters another medium from one medium. Aspherical lenses change the incident angle and refraction angle of light at different positions through the unique aspherical surface shape, so that the light can better conform to the ideal imaging optical path after passing through the lens. For example, in terms of correcting spherical aberration, the light at the edge of the spherical lens often cannot converge to the same focal position as the central light after refraction, resulting in blurred imaging. However, aspherical lenses can allow the edge light to accurately converge to the ideal focus through reasonable peripheral thickness design, etc., greatly improving imaging clarity.

[0081] The embodiment of the present invention further provides a display device, including the optical module described in the above embodiments. The display device can be a wearable device such as AR, VR, etc., or other devices, which is not limited in this application.

[0082] The optical module is located between the human eye and the display screen, and is arranged in the light emitting direction of the display screen, and the fifth lens G5 is arranged closer to the display screen than the first lens G1, and the optical module is used to modulate the light signal emitted by the display screen and transmit it to the human eye. The image information emitted from the display screen enters the human eye through the optical system, and the user can observe a high-definition magnified virtual image, which has a good user experience.

[0083] An optical module and a display device provided by an embodiment of the present invention, the optical module includes a lens group, the lens group includes a first lens, a second lens, a third lens, a fourth lens and a fifth lens in order from the image side to the object side, and the optical focal length is set to positive, negative, positive, positive, and negative in sequence; the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all plastic straight-through lenses. In the present application, the light emitted by the image source passes through each lens in the lens group in sequence to form an image on the image side. Since the lenses in the lens group are all plastic straight-through lenses, the optical module can be made thinner and more efficient, thereby reducing the power consumption of the head-mounted device and improving the wearing comfort.

[0084] It should be noted that:

[0085] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0086] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed method should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the claims below, the inventive aspects are less than all the features of the single embodiment disclosed above. Therefore, the claims following the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0087] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0088] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims below, any one of the claimed embodiments may be used in any combination.

[0089] The various component embodiments of the present application can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or digital signal processor (DSP) can be used in practice to implement some or all functions of some or all components in the creation device of the virtual machine according to the embodiment of the present application. The application can also be implemented as a device or device program (e.g., computer program and computer program product) for executing part or all of the methods described herein. Such a program implementing the present application can be stored on a computer-readable medium, or can have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0090] It should be noted that the above embodiments illustrate the present application rather than limit the present application, and that those skilled in the art may design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets should not be constructed as a limitation to the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of multiple such elements. The present application may be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In a unit claim that lists several devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names.

[0091] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. An optical module, characterized in that: The optical module comprises a lens group, which comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens in order from the image side to the object side, and the optical power is sequentially set to positive, negative, positive, positive, and negative; Wherein, the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all plastic lenses.

2. The optical module according to claim 1, characterized in that: The first lens is a biconvex lens, the second lens is a biconcave lens, the third lens is a biconvex lens, the fourth lens is a meniscus lens with the concave surface facing the object side, and the fifth lens is a biconcave lens.

3. The optical module according to claim 2, characterized in that: The first lens, the second lens, the third lens, the fourth lens and the fifth lens are all aspherical lenses.

4. The optical module according to claim 1, characterized in that: The optical module satisfies: 1<(f1+f2+f3+f4+f5) / F<2; Among them, F is the total effective focal length of the optical module, 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.

5. The optical module according to claim 4, characterized in that: The optical module satisfies the following conditions: 1.2<f1 / F<1.5; -2.5<f2 / F<-2; 1.5<f3 / F<2; 0.9<f1 / f4<1.1; 3<f2 / f5<4; 1.2<f3 / f1<1.5; -1.8<f2 / f1<-1.5; -1.5<f2 / f3<-1.

6. The optical module according to claim 1, characterized in that: The optical module meets the requirement that the eye movement range is greater than 8 mm.

7. The optical module according to claim 1, characterized in that: The optical module meets the requirement that the pupil distance is greater than 15 mm.

8. The optical module according to claim 2, characterized in that: The first lens, the second lens and the third lens constitute a triplet lens.

9. The optical module according to claim 1, characterized in that: The surfaces of the first lens, the second lens, the third lens, the fourth lens and the fifth lens are all coated with anti-reflection films.

10. A display device, characterized in that: Comprising the optical module as described in any one of claims 1-9.

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