Optical machine module and near-to-eye display equipment

Abstract

The invention discloses an optical machine module and near-to-eye display equipment, and relates to the technical field of optics, the optical machine module comprises an image source and a plastic free-form surface lens, the plastic free-form surface lens comprises a plurality of free-form surfaces, and the plurality of free-form surfaces at least comprise a first free-form surface, a second free-form surface and a third free-form surface; the third free-form surface is provided with a polarizing beam-splitting film which transmits the S polarized light and reflects the P polarized light; p polarized light emitted or reflected by the image source enters the first free-form surface after being transmitted by the second free-form surface, is totally reflected to the third free-form surface through the first free-form surface, and is emitted through the first free-form surface after being reflected by the third free-form surface. The optical lens of the optical machine module is made of plastic, so that the mass production cost can be greatly reduced. A traditional polarization splitting prism is omitted, the plastic free-form surface lens is arranged, the function of imaging illumination light path multiplexing is reserved, the device is suitable for various chips, and the overall light machine size is greatly reduced.

Description

Technical Field

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

[0002] In recent years, Augmented Reality (AR) technology has developed rapidly. Researchers have proposed various solutions, such as Birdbath, prism, free-form surface, and optical waveguide technologies. Among the first three solutions, there is often a contradiction between a good product form and a better display effect. The optical waveguide can effectively solve the above problems, and the solution of an optical engine plus an optical waveguide is a lightweight and miniaturized, and the most important future AR development solution.

[0003] In the optical waveguide technology solution, an optical engine, that is, an optical engine, is required as an image generation unit. Generally speaking, the optical waveguide can currently be made thin and light, and its form has approached the size and shape of a myopia glasses lens; currently, there are various solutions for the optical engine based on micro light-emitting diode chips, liquid crystal on silicon chips, and organic light-emitting diode chips. Different solutions generally have volumes ranging from 0.2 to 2 cc according to different requirements for important optical parameters such as the field of view angle, clarity, and brightness.

[0004] Currently, the common self-luminous screens are micro light-emitting diode chips or organic light-emitting diode chips. The AR optical engine design based on such self-luminous screens will be similar to a projection imaging lens and will have a relatively large size in the longitudinal direction; the currently generally used screen based on passive light emission is of the liquid crystal on silicon chip type. Passive light emission means that an additional illumination optical path design is required, so it will have a higher brightness than the self-luminous AR optical engine solution. However, at the same time, due to the polarization characteristics of the liquid crystal on silicon chip itself, a relatively large-sized polarization beam splitter prism is required. Therefore, the optical engine of the liquid crystal on silicon chip is generally 4 to 5 times larger than the self-luminous AR optical engine. However, currently, the volume of the optical engine of the liquid crystal on silicon chip can also be made less than 1 cc. How to further reduce the volume of the optical engine is a problem that those skilled in the art need to solve. Summary of the Invention

[0005] The present invention provides an optical engine module and a near-eye display device, which can not only be applicable to various chips, but also have a small volume and low cost.

[0006] In a first aspect, an embodiment of the present invention provides an optical engine module, including an image source and a plastic free-form surface lens. The plastic free-form surface lens includes a plurality of free-form surfaces, and the plurality of free-form surfaces at least include: a first free-form surface, a second free-form surface, and a third free-form surface; a polarization beam splitting film is disposed on the third free-form surface, and the polarization beam splitting film transmits S-polarized light and reflects P-polarized light.

[0007] After the P-polarized light emitted or reflected by the image source is transmitted through the second free-form surface, it is incident on the first free-form surface, totally reflected by the first free-form surface to the third free-form surface, reflected by the third free-form surface, and then exits through the first free-form surface.

[0008] Optionally, the sag height z of the free-form surface satisfies: ; where c is the radius of curvature of the free-form surface, r is the radial radius coordinate of the free-form surface, k is the aspheric coefficient of the free-form surface, is the polynomial in the first direction x and the second direction y of the free-form surface. The first direction x is the axisymmetric direction of the free-form surface, the second direction y is the non-axisymmetric direction of the free-form surface, the first direction x and the second direction y are perpendicular, N is the total number of polynomial coefficients in the series, is the coefficient of the i-th extended polynomial;

[0009] Among them, the maximum number of extended terms of the first free-form surface is greater than 10. The focal length f1x in the first direction x satisfies: -300 mm ≤ f1x ≤ -80 mm, and the focal length f1y in the second direction y satisfies: 150 mm ≤ f1y ≤ 480 mm; the maximum number of extended terms of the second free-form surface is greater than 10. The focal length f2x in the first direction x satisfies: -40 mm ≤ f2x ≤ -10 mm, and the focal length f2y in the second direction y satisfies: 16 mm ≤ f2y ≤ 100 mm; the maximum number of extended terms of the third free-form surface is greater than 20. The focal length f3x in the first direction x satisfies: 10 mm ≤ f3x ≤ 100 mm, and the focal length f3y in the second direction y satisfies: 15 mm ≤ f3y ≤ 160 mm.

[0010] Optionally, it further includes: an illumination light source, a collimating element, and a fly-eye homogenizing element;

[0011] The light emitted by the illumination light source is collimated by the collimating element and then enters the fly-eye homogenizing element. After being subdivided into multiple light spots by the fly-eye units in the fly-eye homogenizing element, it becomes S-polarized light after passing through the third free-form surface, is totally reflected by the first free-form surface, is transmitted from the second free-form surface to the image source, and then is converted into P-polarized light by the image source. The P-polarized light is transmitted through the second free-form surface, is incident on the first free-form surface, is totally reflected by the first free-form surface to the third free-form surface, is reflected by the third free-form surface, and then exits through the first free-form surface.

[0012] Optionally, the collimating element includes a first collimating lens, and the refractive index of the first collimating lens is greater than 1.6;

[0013] At least one surface of the first collimating lens is a convex surface, and the convex surface is an even aspherical surface;

[0014] The focal length f1 of the first collimating lens satisfies: 1 mm ≤ f1 ≤ 5.5 mm.

[0015] Optionally, the collimating element includes a second collimating lens and a third collimating lens arranged in sequence in the light emitting direction of the illumination light source. The second collimating lens includes a glass convex lens, and the third collimating lens includes an even aspherical lens;

[0016] The second collimating lens includes at least one convex surface, and the focal length f2 of the second collimating lens satisfies: 2 mm ≤ f2 ≤ 4.5 mm;

[0017] Both surfaces of the third collimating lens are convex surfaces and are both even aspherical surfaces. The focal length f3 of the third collimating lens satisfies: 2 mm ≤ f3 ≤ 4.5 mm.

[0018] Optionally, the compound eye light homogenizing element includes a double-sided microstructure, and the double-sided microstructure includes a compound eye horizontal cell and a compound eye vertical cell. The number of the compound eye horizontal cells and the number of the compound eye vertical cells are both greater than 7, and the shapes of the compound eye horizontal cells and the compound eye vertical cells are both rectangles or hexagons or circles.

[0019] Optionally, the field of view angle of the image source is less than or equal to 50 degrees, and the size is 0.13 inches.

[0020] Optionally, the image source is a self-luminous pixel.

[0021] Optionally, it further includes: a waveguide sheet, the input end of the waveguide sheet corresponds to the output end of the first free-form surface, and is used to receive the light output by the first free-form surface;

[0022] The waveguide sheet includes a diffraction waveguide or an array waveguide.

[0023] In a second aspect, an embodiment of the present invention further provides a near-eye display device, including the optical engine module described in the first aspect.

[0024] An embodiment of the present invention provides an optical engine module and a near-eye display device. The optical engine module includes an image source and a plastic free-form surface lens. The plastic free-form surface lens includes a plurality of free-form surfaces, and the plurality of free-form surfaces at least include: a first free-form surface, a second free-form surface, and a third free-form surface; a polarization beam splitter film is disposed on the third free-form surface, and the polarization beam splitter film transmits S-polarized light and reflects P-polarized light; the P-polarized light emitted or reflected by the image source is transmitted through the second free-form surface and then incident on the first free-form surface, totally reflected by the first free-form surface to the third free-form surface, reflected by the third free-form surface, and then emitted through the first free-form surface. The optical lens of the optical engine module in the embodiment of the present invention is made of plastic, which can greatly reduce the mass production cost. At the same time, the traditional polarization beam splitter prism is cancelled. By setting the plastic free-form surface lens, the function of imaging illumination optical path multiplexing is retained, which is applicable to a variety of chips and also greatly reduces the overall volume of the optical engine. It can not only be applicable to a variety of chips, but also has a small volume and low cost.

[0025] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 is a schematic structural diagram of an optical engine module provided by an embodiment of the present invention;

[0028] Figure 2 is a schematic structural diagram of another optical engine module provided by an embodiment of the present invention;

[0029] Figure 3 is a schematic structural diagram of a collimating element provided by an embodiment of the present invention;

[0030] Figure 4 is a schematic structural diagram of another collimating element provided by an embodiment of the present invention;

[0031] Figure 5 is a partial schematic structural diagram of a fly-eye homogenizing element provided by an embodiment of the present invention;

[0032] Figure 6 is a schematic diagram of a fly-eye horizontal cell and a fly-eye vertical cell provided by an embodiment of the present invention;

[0033] Figure 7 It is a schematic structural diagram of another optical engine module provided by an embodiment of the present invention. Detailed implementation manners

[0034] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0035] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order different from those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0036] Figure 1 It is a schematic structural diagram of an optical engine module provided by an embodiment of the present invention. Refer to Figure 1 , the optical engine module includes an image source 110 and a plastic free-form surface lens 120. The plastic free-form surface lens 120 includes a plurality of free-form surfaces, and the plurality of free-form surfaces at least include: a first free-form surface 121, a second free-form surface 122, and a third free-form surface 123. A polarization beam splitter film is provided on the third free-form surface 123, and the polarization beam splitter film transmits S-polarized light and reflects P-polarized light. The P-polarized light emitted or reflected by the image source 110 is transmitted through the second free-form surface 122 and then incident on the first free-form surface 121, totally reflected by the first free-form surface 121 to the third free-form surface 123, reflected by the third free-form surface 123, and then emitted through the first free-form surface 121.

[0037] Specifically, the image source 110 may include a micro light-emitting diode chip, a liquid crystal on silicon chip, or an organic light-emitting diode chip. Among them, the micro light-emitting diode chip and the organic light-emitting diode chip are self-luminous chips, and the liquid crystal on silicon chip is a passive light-emitting chip.

[0038] It can be understood that since the plastic free-form lens 120 includes multiple free-form surfaces, the multiple free-form surfaces at least include: a first free-form surface 121, a second free-form surface 122, and a third free-form surface 123, and a polarization beam splitter film is provided on the third free-form surface 123, and the polarization beam splitter film transmits S-polarized light and reflects P-polarized light. Therefore, the plastic free-form lens 120 can replace the traditional polarization beam splitter prism and retain the function of imaging and illumination optical path multiplexing, and is applicable to various chips.

[0039] It should be noted that when the image source 110 uses a passive light-emitting chip, an illumination optical path needs to be set. When the image source 110 uses a self-luminous chip, the function of the optical engine can be satisfied without setting an illumination optical path and a polarization beam splitter.

[0040] In the optical machine module of the embodiment of the present invention, the material of the optical lens is plastic, which can greatly reduce the mass production cost. At the same time, the traditional polarization beam splitter prism is cancelled. By setting the plastic free-form lens 120, the function of imaging and illumination optical path multiplexing is retained, which is applicable to various chips, and also greatly reduces the overall volume of the optical engine.

[0041] Optionally, on the basis of the above embodiment, the sagittal height z of the free-form surface satisfies: ; where c is the radius of curvature of the free-form surface, r is the radial radius coordinate of the free-form surface, k is the aspheric coefficient of the free-form surface, is a polynomial in the first direction x and the second direction y of the free-form surface. The first direction x is the axisymmetric direction of the free-form surface, the second direction y is the non-axisymmetric direction of the free-form surface, the first direction x and the second direction y are perpendicular, N is the total number of polynomial coefficients in the series, is the coefficient of the i-th extended polynomial.

[0042] Exemplarily, can include: x, y, , xy, , , , , … and so on.

[0043] Among them, the maximum expansion term of the first free-form surface 121 is greater than 10 terms. The focal length f1x in the first direction x satisfies: -300 mm ≤ f1x ≤ -80 mm, and the focal length f1y in the second direction y satisfies: 150 mm ≤ f1y ≤ 480 mm; the maximum expansion term of the second free-form surface 122 is greater than 10 terms. The focal length f2x in the first direction x satisfies: -40 mm ≤ f2x ≤ -10 mm, and the focal length f2y in the second direction y satisfies: 16 mm ≤ f2y ≤ 100 mm; the maximum expansion term of the third free-form surface 123 is greater than 20 terms. The focal length f3x in the first direction x satisfies: 10 mm ≤ f3x ≤ 100 mm, and the focal length f3y in the second direction y satisfies: 15 mm ≤ f3y ≤ 160 mm.

[0044] Figure 2 is a schematic structural diagram of another optical engine module provided by an embodiment of the present invention. Optionally, on the basis of the above embodiment, referring to Figure 2 , the optical engine module further includes: an illumination light source 130, a collimating element 140, and a fly-eye homogenizing element 150; the light emitted by the illumination light source 130 enters the fly-eye homogenizing element 150 after being collimated by the collimating element 140. After being subdivided into multiple light spots by the fly-eye unit in the fly-eye homogenizing element 150, it becomes S-polarized light after passing through the third free-form surface 123, is totally reflected by the first free-form surface 121, and then transmitted through the second free-form surface 122 to the image source 110, and then is converted into P-polarized light by the image source 110. After the P-polarized light is transmitted through the second free-form surface 122, it is incident on the first free-form surface 121, is totally reflected by the first free-form surface 121 to the third free-form surface 123, and after being reflected by the third free-form surface 123, exits through the first free-form surface 121 ( Figure 2 the green lines in are the normal lines).

[0045] Among them, the illumination light source 130 can be a 4-in-1 or multi-in-1 light-emitting diode light source, including red, green, and blue three-color lights, and can form white light by circuit current ratio.

[0046] It should be noted that the image source in this embodiment uses a passive light-emitting chip, specifically a liquid crystal on silicon chip. In the embodiment of the present invention, the multiple light spots formed by the subdivision of the fly-eye unit in the fly-eye homogenizing element 150 will evenly illuminate the liquid crystal on silicon chip at different angles, that is, the fly-eye homogenizing principle is utilized. The fly-eye aperture and the optical engine exit pupil are conjugate images of each other, and the plastic free-form surface lens 120 acts as an integrating lens. For example, the light of the 0 field-of-view aperture of the fly-eye becomes S-polarized light after passing through the third free-form surface 123.

[0047] In other embodiments, when the liquid crystal on silicon chip adjusts the dark field, the S-polarized light incident on the liquid crystal on silicon chip is no longer modulated, and the S-polarized light reflected by the liquid crystal on silicon chip will pass through the third free-form surface 123 to form a dark field at the optical engine exit pupil.

[0048] Figure 3 This is a schematic structural diagram of a collimating element provided by an embodiment of the present invention. Optionally, based on the above embodiment, with reference to Figure 3 , the collimating element 140 includes a first collimating lens 141, and the refractive index of the first collimating lens 141 is greater than 1.6; at least one surface of the first collimating lens 141 is a convex surface, and the convex surface is an even aspherical surface; the focal length f1 of the first collimating lens 141 satisfies: 1 mm ≤ f1 ≤ 5.5 mm.

[0049] Among them, when the material of the first collimating lens 141 in this embodiment is plastic and the materials of the optical lenses in the opto-mechanical module are all plastic, the mass production cost can be further reduced.

[0050] Figure 4 This is another schematic structural diagram of a collimating element provided by an embodiment of the present invention. Optionally, based on the above embodiment, with reference to Figure 4 , the collimating element 140 includes a second collimating lens 142 and a third collimating lens 143 arranged in sequence in the light emitting direction of the illumination light source 130. The second collimating lens 142 includes a glass convex lens, and the third collimating lens 143 includes an even aspherical lens; the second collimating lens 142 includes at least one convex surface, and the focal length f2 of the second collimating lens 142 satisfies: 2 mm ≤ f2 ≤ 4.5 mm; both surfaces of the third collimating lens 143 are convex surfaces and are both even aspherical surfaces, and the focal length f3 of the third collimating lens 143 satisfies: 2 mm ≤ f3 ≤ 4.5 mm.

[0051] Figure 5 This is a partial schematic structural diagram of a compound eye homogenizing element provided by an embodiment of the present invention. Figure 6 This is a schematic diagram of a compound eye horizontal cell and a compound eye vertical cell provided by an embodiment of the present invention. Optionally, based on the above embodiment, with reference to Figure 5 and Figure 6 , the compound eye homogenizing element 150 includes a double-sided microstructure 151. The double-sided microstructure includes a compound eye horizontal cell and a compound eye vertical cell. The number of compound eye horizontal cells and the number of compound eye vertical cells are both greater than 7, and the shapes of the compound eye horizontal cells and the compound eye vertical cells are both rectangles or hexagons or circles.

[0052] It should be noted that the double-sided microstructure 151 is a microstructure provided on the surfaces of the compound eye homogenizing element 150 on the side close to the illumination light source 130 and the side far from the illumination light source 130. Figure 6 Only some compound eye horizontal cells and compound eye vertical cells of the compound eye homogenizing element 150 are shown in

[0053] Optionally, based on the above embodiments, the field of view angle of the image source 110 is less than or equal to 50 degrees, and the size is 0.13 inches.

[0054] It should be noted that if the image source 110 is designed with an index of a field of view angle of 30 degrees and a size of 0.13 inches, the volume of the optical engine module provided by the embodiments of the present invention is 70% of that of the traditional design scheme.

[0055] Optionally, the image source 110 is a self-luminous pixel.

[0056] Specifically, when the image source 110 is a self-luminous pixel, a micro light-emitting diode chip or an organic light-emitting diode chip can be used. At this time, the optical functions of the optical engine can be satisfied without setting up an illumination optical path and a polarization beam splitter.

[0057] Figure 7 is a schematic structural diagram of another optical engine module provided by the embodiments of the present invention. Optionally, based on the above embodiments, continue to refer to Figure 7 , the optical engine module further includes: a waveguide sheet 160. The input end of the waveguide sheet 160 corresponds to the output end of the first free-form surface 121, and is used to receive the light output by the first free-form surface 121; the waveguide sheet 160 includes a diffractive waveguide or an array waveguide ( Figure 7 The green line in is the normal).

[0058] In summary, the optical lenses of the optical engine module in the embodiments of the present invention are made of plastic, which will greatly reduce the mass production cost. At the same time, the traditional polarization beam splitter prism is cancelled. By setting the plastic free-form surface lens 120, the function of imaging and illumination optical path multiplexing is retained, which is applicable to various chips and also greatly reduces the overall volume of the optical engine. When the image source 110 uses a passive light-emitting chip, only an illumination optical path needs to be additionally set. When the image source 110 uses a self-luminous chip, the optical functions of the optical engine can be satisfied without setting up an illumination optical path and a polarization beam splitter. The extremely simple lens architecture and lens material of the present invention contribute to a significant reduction in the cost of the optical engine. In addition, when the material of the first collimating lens 141 is plastic and the materials of the optical lenses in the optical engine module are all plastic, the mass production cost can be further reduced.

[0059] The embodiments of the present invention also provide a near-eye display device, including the optical engine module provided by the above embodiments.

[0060] Since the near-eye display device provided by the embodiments of the present invention includes the optical engine module provided by the above embodiments, it has the same beneficial effects. For the content not described in detail in this embodiment, reference can be made to the optical engine module provided by the above embodiments.

[0061] The above specific embodiments do not constitute a limitation on the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An optical-mechanical module, characterized in that, It includes an image source and a plastic free-form lens. The plastic free-form lens includes a plurality of free-form surfaces, and the plurality of free-form surfaces at least include: a first free-form surface, a second free-form surface, and a third free-form surface; a polarization beam splitter film is provided on the third free-form surface, and the polarization beam splitter film transmits S-polarized light and reflects P-polarized light. The P-polarized light emitted or reflected by the image source is transmitted through the second free-form surface and then incident on the first free-form surface. After being totally reflected by the first free-form surface to the third free-form surface and reflected by the third free-form surface, it is emitted from the first free-form surface.

2. The optical machine module according to claim 1, wherein The sagittal height z of the freeform surface satisfies: ; where c is the radius of curvature of the freeform surface, r is the radial radius coordinate of the freeform surface, k is the aspheric coefficient of the freeform surface, is a polynomial in the first direction x and the second direction y of the freeform surface, the first direction x is the axisymmetric direction of the freeform surface, the second direction y is the non-axisymmetric direction of the freeform surface, the first direction x and the second direction y are perpendicular, and N is the total number of polynomial coefficients in the series, is the coefficient of the i-th extended polynomial; Among them, the maximum expansion term of the first free-form surface is greater than 10 terms. The focal length f1x in the first direction x satisfies: -300 mm ≤ f1x ≤ -80 mm, and the focal length f1y in the second direction y satisfies: 150 mm ≤ f1y ≤ 480 mm; the maximum expansion term of the second free-form surface is greater than 10 terms. The focal length f2x in the first direction x satisfies: -40 mm ≤ f2x ≤ -10 mm, and the focal length f2y in the second direction y satisfies: 16 mm ≤ f2y ≤ 100 mm; the maximum expansion term of the third free-form surface is greater than 20 terms. The focal length f3x in the first direction x satisfies: 10 mm ≤ f3x ≤ 100 mm, and the focal length f3y in the second direction y satisfies: 15 mm ≤ f3y ≤ 160 mm.

3. The optical engine module according to claim 1, wherein, It further includes: a lighting source, a collimating element, and a fly-eye homogenizing element; The light emitted by the lighting source is collimated by the collimating element and then enters the fly-eye homogenizing element. After being subdivided into a plurality of light spots by the fly-eye units in the fly-eye homogenizing element, it becomes S-polarized light after passing through the third free-form surface, is totally reflected by the first free-form surface, is transmitted from the second free-form surface to the image source, and then is converted into P-polarized light by the image source. The P-polarized light is transmitted through the second free-form surface and then incident on the first free-form surface. After being totally reflected by the first free-form surface to the third free-form surface and reflected by the third free-form surface, it is emitted from the first free-form surface.

4. The optical engine module according to claim 3, characterized in that The collimating element includes a first collimating lens, and the refractive index of the first collimating lens is greater than 1.6; At least one surface of the first collimating lens is a convex surface, and the convex surface is an even aspherical surface; The focal length f1 of the first collimating lens satisfies: 1 mm ≤ f1 ≤ 5.5 mm.

5. The optical machine module according to claim 3, characterized in that The collimating element includes a second collimating lens and a third collimating lens arranged in sequence in the light-emitting direction of the lighting source. The second collimating lens includes a glass convex lens, and the third collimating lens includes an even aspherical lens; The second collimating lens includes at least one convex surface, and the focal length f2 of the second collimating lens satisfies: 2 mm ≤ f2 ≤ 4.5 mm; Both surfaces of the third collimating lens are convex surfaces and are both even aspherical surfaces, and the focal length f3 of the third collimating lens satisfies: 2 mm ≤ f3 ≤ 4.5 mm.

6. The optical engine module according to claim 3, wherein, The compound-eye light homogenizing element includes a double-sided microstructure, the double-sided microstructure includes compound-eye horizontal cells and compound-eye vertical cells, wherein the number of the compound-eye horizontal cells and the number of the compound-eye vertical cells are both greater than 7, and the shapes of the compound-eye horizontal cells and the compound-eye vertical cells are both rectangles or hexagons or circles.

7. The optical engine module according to claim 3, wherein The field of view angle of the image source is less than or equal to 50 degrees, and the size is 0.13 inches.

8. The optical engine module according to claim 1 or 2, characterized in that, The image source is a self-luminous pixel.

9. The optical machine module according to claim 1, wherein Further comprising: A waveguide sheet, the input end of the waveguide sheet corresponding to the output end of the first free-form surface for receiving the light output by the first free-form surface; The waveguide sheet includes a diffractive waveguide or an array waveguide.

10. A near-eye display device, characterized in that, Comprising the optical-mechanical module according to any one of claims 1-9.

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