CN115616774A

CN115616774A - Aperture-divided micro-projection device and method thereof

Info

Publication number: CN115616774A
Application number: CN202111242573.1A
Authority: CN
Inventors: 胡雪蕾; 郑旭君; 楼歆晔; 林涛
Original assignee: Shanghai Kunyou Technology Co ltd
Current assignee: Shanghai Kunyou Technology Co ltd
Priority date: 2021-07-15
Filing date: 2021-10-25
Publication date: 2023-01-17

Abstract

A micro-projection device with a split aperture and a method thereof can realize a large aperture, keep smaller volume and weight, avoid the condition of low illumination of an edge field caused by the large aperture and increase uniformity and brightness on the pupil. The aperture type micro-projection device is combined with an optical waveguide to form an augmented reality device, wherein the aperture type micro-projection device comprises: at least one image source for emitting a plurality of beams of image light; and the plurality of sub-aperture lenses are arranged on the light emitting side of the at least one image source side by side, correspond to the plurality of beams of image light emitted by the at least one image source one by one and are used for modulating the corresponding image light to project the image light to the coupling-in area of the optical waveguide.

Description

Aperture-dividing micro-projection device and method thereof

Technical Field

The invention relates to the technical field of augmented reality, in particular to a sub-aperture type micro-projection device and a method thereof.

Background

Augmented Reality (AR), which is a technology for seamlessly integrating virtual world information and real world information, projects pixels on a pico projector into human eyes through an optical combiner, and simultaneously sees the real world through the optical combiner, i.e., superimposes virtual content provided by the pico projector and a real environment on the same picture or space in real time to exist simultaneously, so that a user obtains a virtual and real fused experience. Therefore, one of the design requirements of the optical combiner is that the front sight cannot be blocked and the optical combiner has high transmittance.

In the prior art, there are various implementations of augmented reality systems, which mainly include an optical machine (including an illumination system, a micro display screen, and an imaging system) and an optical combiner (such as a beam splitter prism, a free-form surface, a birdbath, or an optical waveguide). However, from the perspective of optical effect, appearance and mass production, the optical waveguide is the best augmented reality scheme at present, and has excellent development potential. As is well known, the basis of an optical waveguide is a thin, transparent glass substrate (the thickness of which is typically in the order of a few millimeters or sub-millimeters) so that light travels by total reflection back and forth between the upper and lower surfaces of the glass substrate, i.e., when the refractive index of a transmission medium is greater than that of the surrounding medium and the incident angle in the waveguide is greater than the critical angle for total reflection, the light can be transmitted without leakage by total reflection within the optical waveguide. In this way, after the image light from the projector has been coupled into the light guide, the image light continues to propagate without loss in the light guide until it is coupled out by the subsequent structures.

Currently, waveguides on the market are generally classified into geometric array waveguides and diffractive light waveguides. The geometric optical waveguide is generally referred to as an array optical waveguide, which implements output of an image and expansion of a movable eye socket through array mirror stacking, so that image quality and efficiency can reach a high level. The diffraction optical waveguide mainly utilizes a surface relief grating waveguide manufactured by a photoetching technology and a holographic body grating waveguide manufactured based on a holographic interference technology, so that the diffraction optical waveguide has extremely high design freedom degree and mass production brought by nano-imprinting processing, and has obvious advantages.

Although the existing optical waveguide can perform one-dimensional pupil expansion and also can perform two-dimensional pupil expansion, when the optical waveguide only performs one-dimensional pupil expansion, an optical machine is needed to perform another-dimensional pupil expansion so as to obtain a larger eyebox. However, when the optical engine needs to expand the pupil to obtain a larger eyebox, the pupil (aperture) of the optical engine naturally increases greatly (even to more than 20 mm), so that at a certain angle of view, when the screen used by the projection system is smaller, the F number of the system is reduced to less than 1, which makes the design of the imaging system (i.e. lens) in the optical engine difficult, which not only results in a large increase in the size of the optical engine, but also results in a reduction in image quality. For example, as shown in fig. 1, a conventional optical machine 1P includes a screen 11P with an image plane half height of 1.3mm and a single-aperture lens 12P with a pupil size of 12mm, and the field angle of the optical machine 1P is 15 °, at this time, the F number of the single-aperture lens 12P is about 0.49, and at least ten lenses are required to complete the design of the lens, and the design difficulty is very large. Taking the single-aperture lens 12P designed by ten lenses as an example, the maximum aperture of the optical machine 1P is 23mm, and the total length reaches 26mm, and as is apparent from the MTF graph of the optical machine 1P shown in fig. 2, the image quality of the optical machine 1P is very poor.

Disclosure of Invention

An advantage of the present invention is to provide a micro-projection device with a split aperture and a method thereof that can achieve a large aperture while maintaining a small volume and weight.

An advantage of the present invention is to provide an augmented reality device that can avoid low peripheral field illuminance due to a large aperture, which helps to increase uniformity and brightness across the pupil.

Another advantage of the present invention is to provide a micro-projection device with split-aperture and a method thereof, wherein in an embodiment of the present invention, the micro-projection device with split-aperture can use a plurality of sub-aperture lenses with smaller apertures to replace a single lens with larger aperture, which not only can reduce the volume and weight of the device, but also can reduce the difficulty in designing the lens and improve the image quality.

Another advantage of the present invention is to provide a micro-projection device with split aperture and a method thereof, wherein in an embodiment of the present invention, the micro-projection device with split aperture can arrange the plurality of sub-aperture lenses along a pupil expanding direction different from the optical waveguide to perform a pupil expanding in another dimension direction, thereby implementing a larger eyebox.

Another advantage of the present invention is to provide a split-aperture micro-projection apparatus and a method thereof, wherein, in an embodiment of the present invention, the arrangement direction of the plurality of sub-aperture lenses in the split-aperture micro-projection apparatus is perpendicular to the pupil expanding direction of the optical waveguide, so as to maximize the eyebox.

Another advantage of the present invention is to provide a micro-projection device with split aperture and a method thereof, wherein, in an embodiment of the present invention, the fields of view of a plurality of sub-aperture lenses in the micro-projection device with split aperture partially overlap to ensure continuity of the eyebox range.

Another advantage of the present invention is to provide a split-aperture micro-projection apparatus and a method thereof, wherein, in an embodiment of the present invention, an optical waveguide is disposed at an overlapping of fields of view of the plurality of sub-aperture lenses of the split-aperture micro-projection apparatus to minimize the size of the device while achieving a continuous eyebox range.

Another advantage of the present invention is to provide an aperture-dividing micro-projection apparatus and a method thereof, wherein in an embodiment of the present invention, the aperture-dividing micro-projection apparatus may include a plurality of sub-image sources corresponding to the plurality of sub-aperture lenses one to one, which helps to increase the uniformity of illumination across the pupil while reducing the difficulty of design.

Another advantage of the present invention is to provide a micro-projection device with split-aperture and a method thereof, wherein in an embodiment of the present invention, the micro-projection device with split-aperture may also include a single image source corresponding to the plurality of sub-aperture lenses, which is helpful to reduce the cost and the adjustment difficulty.

Another advantage of the present invention is to provide an aperture-dividing micro-projection apparatus and method thereof, wherein it is not necessary to use expensive materials or complicated structures in the present invention in order to achieve the above objects. The present invention therefore successfully and efficiently provides a solution that not only provides a sub-aperture micro-projection device and method, but also increases the practicality and reliability of the same.

To achieve at least one of the above advantages or other advantages and objects, the present invention provides a split-aperture type micro-projection apparatus combined with a light guide to form an augmented reality device, wherein the split-aperture type micro-projection apparatus includes:

at least one image source for emitting a plurality of beams of image light; and

and the plurality of sub-aperture lenses are arranged on the light emitting side of the at least one image source side by side, correspond to the plurality of beams of image light emitted by the at least one image source one by one, and are used for modulating the corresponding image light to project the image light to the coupling-in area of the optical waveguide.

According to an embodiment of the present application, the arrangement direction of the plurality of sub-aperture lenses is not parallel to the pupil expanding direction of the optical waveguide.

According to an embodiment of the present application, the arrangement direction of the plurality of sub-aperture lenses is perpendicular to the pupil expanding direction of the optical waveguide.

According to an embodiment of the present application, each of the sub-aperture lenses includes a lens group and a stop, wherein the stop is disposed in an optical axis direction of the lens group, and the lens group is located between the stop and the image source.

According to an embodiment of the present application, the overlapping positions of the fields of view of the adjacent sub-aperture lenses are suitable for arranging the optical waveguide.

According to an embodiment of the present application, each of the indexes in the multi-aperture micro-projection device satisfies the following formula:

(2*p*tanω+d)*n≥D (1)

wherein: p is the distance between the optical waveguide and the diaphragm; omega is the half field angle of the multi-aperture type micro-lens device; d is the aperture of the diaphragm of the sub-aperture lens; n is the number of the sub-aperture lenses; d is the pupil required by the multi-aperture microlens device; and L is the sub-aperture distance of the adjacent sub-aperture lenses.

According to an embodiment of the application, the required pupil D of the multi-aperture micro-projection device is between 10mm and 30mm.

According to an embodiment of the present application, the half field angle ω of the multi-aperture micro-projection apparatus is between 5 ° and 90 °.

According to an embodiment of the application, the at least one image source is a plurality of sub-image sources arranged side by side, wherein the plurality of sub-image sources correspond to the plurality of sub-aperture lenses one to one, and the sub-aperture lenses are configured to modulate image light emitted by the corresponding sub-image sources to be projected to the optical waveguide.

According to an embodiment of the application, the sub-image source is a screen with a diagonal half-length of 1.3 mm.

According to an embodiment of the present application, the at least one image source is a single image source, wherein the single image source corresponds to the plurality of sub-aperture lenses, and the single image source is configured to emit a plurality of beams of image light corresponding to the plurality of sub-aperture lenses one-to-one.

According to an embodiment of the application, the single image source is a 5.9mm diagonal half-length screen.

According to an embodiment of the application, the at least one image source is a Micro-LED screen or an OLED screen.

According to another aspect of the present application, there is further provided a method of manufacturing a micro-projection device of the split-aperture type, comprising the steps of:

providing at least one image source; and

and arranging a plurality of sub-aperture lenses side by side on the light emitting side of the at least one image source, wherein the plurality of sub-aperture lenses are in one-to-one correspondence with a plurality of image lights emitted by the at least one image source and are used for modulating the corresponding image lights to project the image lights to the coupling-in area of the optical waveguide.

According to an embodiment of the present application, in the step of providing at least one image source: and arranging a plurality of sub-image sources side by side to form the at least one image source, wherein the plurality of sub-image sources correspond to the plurality of sub-aperture lenses in a one-to-one manner, and the sub-aperture lenses are used for modulating image light emitted by the corresponding sub-image sources to project to the optical waveguide.

According to an embodiment of the application, in the step of providing at least one image source: the at least one image source is a single image source, wherein the single image source corresponds to the plurality of sub-aperture lenses, and the single image source is configured to emit a plurality of image lights in one-to-one correspondence with the plurality of sub-aperture lenses.

According to an embodiment of the present application, in the step of disposing a plurality of sub-aperture lenses side by side on the light emitting side of the at least one image source, wherein the plurality of sub-aperture lenses are in one-to-one correspondence with a plurality of image lights emitted by the at least one image source, for modulating the corresponding image lights to project onto the coupling-in area of the optical waveguide: the plurality of sub-aperture lenses are arranged along a direction perpendicular to the pupil expanding direction of the optical waveguide.

Further objects and advantages of the invention will be fully apparent from the ensuing description and drawings.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the claims.

Drawings

Fig. 1 shows a schematic structural diagram of a conventional optical machine.

Fig. 2 shows a schematic MTF curve of the above prior art optical machine.

Fig. 3 is a schematic diagram of an application of a multi-aperture micro-projection apparatus according to an embodiment of the invention.

Fig. 4 shows a first example of the sub-aperture lens of the multi-aperture micro-projection apparatus according to the above-described embodiment of the present invention.

Fig. 5 shows a schematic MTF curve of the multi-aperture micro-projection device according to the above first example of the invention.

Fig. 6 shows a distortion curve diagram of the multi-aperture micro-projection apparatus according to the first example of the present invention.

Fig. 7 shows a field curvature diagram of the multi-aperture micro-projection device according to the first example of the invention.

Fig. 8 shows a schematic diagram of the relative illuminance of the multi-aperture micro-projection device according to the first example of the present invention.

Fig. 9 is a schematic structural diagram of another existing optical bench.

Fig. 10 shows a schematic MTF curve of another existing optical machine as described above.

Fig. 11 shows a second example of the sub-aperture lens of the multi-aperture micro-projection apparatus according to the above-described embodiment of the present invention.

Fig. 12 is a schematic structural diagram of an augmented reality device implemented as AR glasses configured with optical waveguides according to an embodiment of the present application.

FIG. 13 is a flow chart illustrating a method for manufacturing a multi-aperture micro-projection device according to an embodiment of the present application.

Detailed Description

The following description is provided to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The underlying principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be constructed and operated in a particular orientation and thus are not to be considered limiting.

In the present invention, the terms "a" and "an" in the claims and the description should be understood as meaning "one or more", that is, one element may be one in number in one embodiment, and the element may be more than one in number in another embodiment. The terms "a" and "an" should not be construed as limiting the number unless the number of such elements is explicitly recited as one in the present disclosure, but rather the terms "a" and "an" should not be construed as being limited to only one of the number.

In the description of the present invention, it is to be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "connected" and "connected" should be interpreted broadly, and may be, for example, a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; they may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

In recent years, with the rapid development of augmented reality technology, devices or apparatuses capable of realizing augmented reality are becoming more popular and used. However, the existing one-dimensional pupil-expanding optical waveguide (including geometric optical waveguide and diffractive optical waveguide) can only expand the exit pupil in one direction (e.g., X direction), and at this time, an optical machine (i.e., a projection device) is required to complete the pupil expansion in the other direction (e.g., Y direction). However, when a larger eyebox is required, the pupil size of the optical engine increases, even to more than 20mm. Thus, under a certain field angle, if the screen adopted by the optical machine is smaller and the focal length is shorter, the F number of the optical machine is reduced to 1, so that the design difficulty of the optical machine becomes more difficult; if a larger screen is used to increase the F number, the focal length will inevitably increase, resulting in an increase in the total length of the optical device and thus an increase in the overall size of the device, which is contrary to the current trend of miniaturization of electronic devices. Accordingly, to solve the above problems, the present invention provides a split aperture type micro-projection apparatus, a method and an apparatus thereof, which can achieve a large aperture while maintaining a small volume and weight.

Referring to fig. 3 to 4, a micro-projection device with a split aperture according to an embodiment of the present application is illustrated, wherein the micro-projection device with a split aperture 1 can be combined with a light guide 2 to form an augmented reality apparatus for projecting image light into the light guide 2 to transmit the image light to the eye of a user through the light guide 2, and external ambient light can penetrate through the light guide 1 to be incident to the eye of the user, so that the user obtains an augmented reality experience.

Specifically, as shown in fig. 3 and 4, the aperture-divided micro-projection apparatus 1 may include at least one image source 10 for emitting a plurality of beams of image light, and a plurality of sub-aperture lenses 20, wherein the plurality of sub-aperture lenses 20 are disposed side by side at a light emitting side of the at least one image source 10, and the plurality of sub-aperture lenses 20 correspond one-to-one to the plurality of beams of image light emitted via the at least one image source 10, for modulating the corresponding image light to be projected to the coupling-in area of the optical waveguide 2, thereby transmitting the image light to the eye of the user through the optical waveguide 2 for imaging.

It should be noted that, because the plurality of sub-aperture lenses 20 of the sub-aperture type micro-projection apparatus 1 are arranged side by side, so that the sub-aperture type micro-projection apparatus 1 can realize a larger pupil (aperture) although the aperture of the sub-aperture lens 20 is smaller, the sub-aperture type micro-projection apparatus 1 of the present invention can divide the required larger pupil (aperture) into a plurality of smaller sub-apertures, which helps to reduce the design difficulty. Meanwhile, a relatively independent small-aperture lens (i.e., the sub-aperture lens 20) is also arranged at the edge part of the field of view corresponding to a large-aperture system (i.e., a single-aperture system), which helps to avoid the problem of dark angle at the pupil edge caused by too large NA angle of the single-aperture system and helps to increase the uniformity on the pupil. In addition, compared with a single-aperture system under the same index, the multi-aperture micro-projection device 1 of the present application is smaller in size and easier to be produced.

More specifically, according to the above embodiment of the present application, the arrangement direction of the plurality of sub-aperture lenses 20 in the split-aperture micro-projection apparatus 1 is not parallel to the pupil expanding direction of the optical waveguide 2, that is, the pupil expanding direction of the split-aperture micro-projection apparatus 1 is different from the pupil expanding direction of the optical waveguide 2, so that the augmented reality device can obtain a sufficiently large eyebox, which is helpful for satisfying the user's usage requirement and obtaining a comfortable wearing experience. It will be appreciated that when the augmented reality device is implemented as AR glasses, the increased range of the orbital (i.e., eyebox) enables the user to move the user's eyes a greater range around the center point of the lens after wearing the AR glasses, yet still see the image clearly, making it easier to adapt the product to all people.

Preferably, the arrangement direction of the plurality of sub-aperture lenses 20 is perpendicular to the pupil expanding direction of the optical waveguide 2. Illustratively, when the pupil expanding direction of the light guide 2 is implemented as the X-axis direction (the direction perpendicular to the paper as shown in fig. 3), the plurality of sub-aperture lenses 20 are preferably arranged along the Y-axis direction (the vertical direction as shown in fig. 3), so that the exit pupil can be expanded along the vertical direction by the split-aperture micro-projection apparatus 1 while the light guide 2 expands the exit pupil along the horizontal direction, which helps to ensure that the augmented reality device obtains a sufficiently large eyebox.

It is noted that the optical waveguide 2 may be implemented as a one-dimensional pupil-expanding optical waveguide. For example, the optical waveguide 2 may be implemented as a geometric optical waveguide capable of performing one-dimensional pupil expansion, or the optical waveguide 2 may also be implemented as a diffractive optical waveguide provided with only one-dimensional grating, as long as one-dimensional pupil expansion is possible, which is not described in detail herein.

Furthermore, the image source 10 in the Micro-aperture Micro-projection device 1 may be, but is not limited to being, implemented as a self-emitting screen such as Micro-LED or OLED.

According to the above-described embodiment of the present application, as shown in fig. 3 and 4, each of the sub-aperture lenses 20 may include a lens group 21 and a stop 22, wherein the stop 22 is disposed in the optical axis direction of the lens group 21, and the lens group 21 is located between the stop 22 and the image source 10, such that the image light emitted via the image source 10 passes through the lens group 21, passes through the stop 22, and then propagates to the coupling-in area of the optical waveguide 2. In other words, the stop 22 of the present application is advanced to define the pupil size of the sub-aperture lens 20 by the stop 22. It is understood that the material of the lenses in the lens group 21 of the sub-aperture lens 20 may be implemented by glass, or may be implemented by transparent resin.

It should be noted that, due to the diaphragm advance characteristic of the sub-aperture lens 20, the aperture of the lens in the lens group 21 which is forward (i.e. close to the diaphragm 22) is larger than the aperture of the diaphragm 22 (i.e. the size of the sub-pupil), so that in order to avoid the collision between the adjacent sub-aperture lenses 20, the sub-pupils of the adjacent sub-aperture lenses 20 in the aperture-dividing micro projection apparatus 1 cannot be connected, and only the optical waveguide 2 can be far away from the diaphragm 22 of the sub-aperture lens 20. Meanwhile, in order not to miss any ray information of the field of view, the optical waveguide 2 is preferably located at a field-of-view overlapping position of the adjacent sub-aperture lenses 20, so as to minimize the length size of the apparatus while ensuring that a continuous eyebox range is achieved. It will be appreciated that in other examples of the application, the optical waveguide 2 may also be arranged at a greater distance from the diaphragm 22, while still ensuring continuity of the eyebox range.

For example, each index in the multi-aperture micro-projection apparatus 1 in the augmented reality device needs to satisfy the following formulas (1) and (2):

(2*p*tanω+d)*n≥D (1)

wherein: p is the distance between the optical waveguide 2 and the diaphragm 22; ω is the half field angle of the multi-aperture microlens device 1; d is the aperture of the diaphragm 22 of the sub-aperture lens 20; n is the number of the sub-aperture lenses 20; d is the pupil required for the multi-aperture microlens device 1; l is the sub-aperture distance of the adjacent sub-aperture lens 20.

In an example of the present application, the pupil D required for the multi-aperture microlens apparatus 1 may be, but is not limited to, implemented to be 10mm to 30mm. Preferably, the pupil D required for the multi-aperture microlens device 1 is implemented as 20mm.

In an example of the present application, the half field angle ω of the multi-aperture microlens apparatus 1 may be, but is not limited to, implemented to be 5 ° to 90 °. Preferably, the half field angle ω of the multi-aperture microlens device 1 is implemented as 15 °.

It should be noted that, in order to reduce the system volume as much as possible, the smaller the sub-aperture distance L of the adjacent sub-aperture lenses 20, the better; in order to reduce the weight and volume of the system, the number of the sub-aperture lenses 20 is as small as possible, but the number of the sub-aperture lenses 20 should be greater than or equal to two. In order to simplify the system as much as possible, the aperture d of the stop 22 of the sub-aperture lens 20 is preferably larger. In order to reduce the system length as much as possible, the distance p between the optical waveguide 2 and the diaphragm 22 is preferably as small as possible.

Further, in an example of the present application, the focal length f of the sub-aperture lens 20 may be, but is not limited to, implemented to be 3mm to 90mm. Preferably, the focal length f of the sub-aperture lens 20 is implemented to be 9.8mm.

In an example of the present application, the F-number of the sub-aperture lens 20 may be, but is not limited to, implemented to be 0.3 to 3.5. Preferably, the F-number of the sub-aperture lens 20 is implemented as 2.

It is noted that in the first example of the present application, as shown in fig. 3, the at least one image source 10 in the multi-aperture microlens apparatus 1 may be implemented as a plurality of sub-image sources 11 arranged side by side, wherein the plurality of sub-image sources 11 are in one-to-one correspondence with the plurality of sub-aperture lenses 20, and the sub-aperture lenses 20 are used for modulating the image light emitted via the corresponding sub-image sources 11 to be projected to the incoupling area of the optical waveguide 2. It can be understood that, since the multi-aperture microlens apparatus 1 includes a plurality of the sub-image sources 11, and the sub-image sources 11 correspond to the sub-aperture lenses 20 one to one, the size of each sub-image source 11 is small, that is, in this example of the application, the image height of the screen required in the multi-aperture microlens apparatus 1 is small, such as a screen with a diagonal half length of 1.3 mm.

Exemplarily, in order to design a micro projection system with a pupil size of 20mm and a field angle of 15 °, the multi-aperture microlens device 1 of the present application may include four sub-image sources 11 and four sub-aperture lenses 20, wherein the sub-image sources 11 are screens with a diagonal half length of 1.3mm, and the aperture of the sub-aperture lenses 20 is 4mm. The focal length of the sub-aperture lens 20 of the multi-aperture microlens device 1 is 9.8mm and the f-number is 2.47, which contributes to reducing the difficulty in designing thereof and can increase the uniformity of illuminance over the entire pupil.

Thus, it can be calculated from the above equations (1) and (2): the minimum distance p between the optical waveguide 2 and the diaphragm 22 is 3.8mm; the sub-aperture distance L of the adjacent sub-aperture lenses 20 is 1mm; the overall length of the multi-aperture microlens device 1 is 11.8mm and the maximum aperture is 12.2mm. Therefore, the overall system volume of the multi-aperture micro-projection device 1 of the present application is greatly reduced compared to the volume of a single-aperture system as shown in fig. 1.

It is to be noted that, since the F number of the sub-aperture lens 20 in this example of the present application is 2.47, the difficulty in designing the sub-aperture lens 20 is reduced, and therefore, as shown in fig. 5, the sub-aperture lens 20 of the present application only needs four lenses to obtain a better imaging quality.

Further, the MTF graph of the multi-aperture micro-projection apparatus 1 according to this example of the present application is shown in fig. 5, the distortion graph is shown in fig. 6, the field curvature graph is shown in fig. 7, and the relative illuminance graph is shown in fig. 8. Therefore, the multi-aperture micro-projection apparatus 1 has good image quality and a relative illumination greater than 85% to obtain good projection quality according to the image quality evaluation curve.

It should be noted that, since the multi-aperture microlens apparatus 1 according to the above-mentioned example of the present application employs a plurality of self-luminous screens (i.e., the sub-image source 11), the multi-aperture microlens apparatus 1 is costly and difficult to adjust. Similarly to the conventional single-aperture imaging scheme shown in fig. 1, in a case where the design criteria (i.e., the pupil size is 20mm and the field angle is 15 °) are kept unchanged, as shown in another single-aperture imaging scheme shown in fig. 9, the half-image height of the screen 21P in the optical engine 2P is increased to 5.9mm, and the F-number of the single-aperture lens 22P in the optical engine 2P is increased to 2.24. At this time, it is known through calculation that the focal length of the single-aperture lens 22P is about 45mm, the entire length of the optical machine 2P is as high as 41mm, the maximum aperture is 21mm, and the distortion reaches 2%, which results in a long total length and a large volume of the optical machine 2P. In addition, as is apparent from the MTF graph of the optical machine 2P shown in fig. 10, the image quality of the optical machine 2P is also poor.

In order to solve the above problem, in the second example of the present application, as shown in fig. 11, the at least one image source 10 in the multi-aperture microlens apparatus 1 may also be implemented as a single image source 12, wherein the single image source 12 corresponds to the plurality of sub-aperture lenses 20, and the single image source 12 is configured to emit a plurality of image lights in one-to-one correspondence with the plurality of sub-aperture lenses 20, such that each of the sub-aperture lenses 20 modulates the corresponding image light emitted via the single image source 12. It can be understood that, since the multi-aperture microlens apparatus 1 includes only one single image source 12, and one single image source 12 needs to correspond to a plurality of sub-aperture lenses 20 at the same time, in this example of the present application, the multi-aperture microlens apparatus 1 only needs to adopt one larger screen to replace a plurality of smaller-sized screens, which helps to reduce the cost and the difficulty of adjustment.

Exemplarily, the single image source 12 of the multi-aperture microlens device 1 may be implemented as a screen having a diagonal half length of 5.9mm, and has a plurality of image areas 120 distributed side by side, and the image areas 120 are in one-to-one correspondence with the sub-aperture lenses 20, so that the sub-aperture lenses 20 can modulate image light emitted via the corresponding image areas 120 to project the image light to corresponding positions of the incoupling area of the light guide 2.

According to another aspect of the present application, as shown in fig. 12, the present application further provides an augmented reality device 4, wherein the augmented reality device 4 may include a multi-aperture micro-projection apparatus 1, an optical waveguide 2, and a device body 3, wherein the multi-aperture micro-projection apparatus 1 and the optical waveguide 2 are correspondingly disposed on the device body 3, such that image light projected via the multi-aperture micro-projection apparatus 1 is transmitted to a user's eye by the optical waveguide 2 to be received to see a corresponding image.

In an example of the present application, as shown in fig. 12, the main body 3 of the augmented reality apparatus 4 may be implemented as an eyeglass frame 31 including a beam portion 311 and a pair of temple portions 312, wherein the temple portions 312 extend rearward from left and right sides of the beam portion 311, respectively, to form the main body 3 of the apparatus having an eyeglass frame structure. The optical waveguide 2 is provided in the beam portion 311 as a spectacle lens for near-eye display.

Exemplarily, as shown in fig. 12, the coupling-in region in the optical waveguide 2 may correspond to the beam portion 311 of the eyeglasses frame 31; at this time, the multi-aperture micro-projector 1 is mounted to the beam portion 311 of the glasses frame 31, so that when the user wears the augmented reality device 4, the multi-aperture micro-projector 1 is correspondingly located near the forehead of the user, which helps to reserve a larger mounting space for the multi-aperture micro-projector 1.

Notably, the augmented reality device 4 may be implemented as a heads-up display (HUD) in addition to the augmented reality device 4 being implemented as AR glasses. As is well known, the HUD is another promising application of the optical waveguide, and particularly, the vehicle-mounted HUD enables a vehicle owner to view relevant information of the vehicle without lowering his head when driving the vehicle, and the eye sight line does not need to be switched back and forth between the road condition and the display, so as to ensure the driving safety and comfort. And AR-HUD combines image information in actual traffic road conditions through inside specially designed optical system accurately, projects information such as tire pressure, speed, rotational speed to the virtual image that forms far away in order to get into people's eye behind windshield reflection for the user just can observe the suggestion information that fuses with actual road conditions through front windshield's display area. In addition, compared with the general W-HUD in the market at present, the AR-HUD has a compact and light structure, can greatly save the installation space in the automobile, has larger intuition for a user, and intuitively guides a driver to advance by combining the real road condition information and showing some information such as virtual arrows in real time, thereby avoiding the situations of crossing the intersection and dispersing the attention of the driver in driving.

According to another aspect of the present application, as shown in fig. 13, an embodiment of the present application further provides a method for manufacturing a multi-aperture micro-projection device, which may include the steps of:

s100: providing at least one image source 10; and

s200: a plurality of sub-aperture lenses 20 are disposed side by side on a light emitting side of the at least one image source 10, wherein the plurality of sub-aperture lenses 20 correspond one-to-one to a plurality of image lights emitted from the at least one image source 10 for modulating the corresponding image lights to project to the coupling-in area of the optical waveguide 2.

It is noted that, in an example of the present application, in the step S100: a plurality of sub-image sources 11 are arranged side by side to form the at least one image source 10, wherein the plurality of sub-image sources 11 are in one-to-one correspondence with the plurality of sub-aperture lenses 20, and the sub-aperture lenses 20 are configured to modulate image light emitted by the corresponding sub-image sources 11 to be projected to the optical waveguide 2.

In another example of the present application, in the step S100: the at least one image source 10 is a single image source 12, wherein the single image source 12 corresponds to the plurality of sub-aperture lenses 20, and the single image source 12 is configured to emit a plurality of image lights corresponding to the plurality of sub-aperture lenses 20 one to one.

In an example of the present application, in the step S200: the plurality of sub-aperture lenses 20 are arranged in a direction perpendicular to the pupil expanding direction of the optical waveguide 2.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the present invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the embodiments, and any variations or modifications may be made to the embodiments of the present invention without departing from the principles described.

Claims

1. A split-aperture micro-projection device for use in combination with an optical waveguide to form an augmented reality apparatus, wherein the split-aperture micro-projection device comprises:

at least one image source for emitting a plurality of beams of image light; and

2. The micro-projection apparatus of claim 1, wherein the plurality of sub-aperture lenses are arranged in a direction not parallel to the pupil expanding direction of the optical waveguide.

3. The micro-projection device of claim 2, wherein the sub-aperture lenses are arranged in a direction perpendicular to the pupil expanding direction of the optical waveguide.

4. The split-aperture micro-projection device of claim 3, wherein each of the sub-aperture lenses comprises a lens group and a stop, wherein the stop is disposed in an optical axis direction of the lens group, and the lens group is located between the stop and the image source.

5. The micro-projection apparatus of claim 4, wherein the overlapping positions of the fields of view of adjacent sub-aperture lenses are suitable for disposing the optical waveguide.

6. The split-aperture micro-projection device of claim 5, wherein each of the criteria in the multi-aperture micro-projection device satisfies the following equation:

(2*p*tanω+d)*n≥D (1)

7. The split-aperture micro-projection device of claim 6, wherein the pupil D required for the multi-aperture micro-projection device is between 10mm and 30mm.

8. The small aperture micro-projection device of claim 6, wherein the half field angle ω of the multi-aperture micro-projection device is between 5 ° and 90 °.

9. The micro-projection apparatus according to any of claims 1 to 8, wherein the at least one image source is a plurality of sub-image sources arranged side by side, wherein the plurality of sub-image sources are in one-to-one correspondence with the plurality of sub-aperture lenses, and the sub-aperture lenses are configured to modulate the image light emitted via the corresponding sub-image sources to be projected to the optical waveguide.

10. The micro-projection apparatus of claim 9, wherein the sub-image source is a screen with a diagonal half-length of 1.3 mm.

11. The aperture-dividing micro-projection device of any one of claims 1-8, wherein the at least one image source is a single image source, wherein the single image source corresponds to the plurality of sub-aperture lenses, and the single image source is configured to emit a plurality of image lights in one-to-one correspondence with the plurality of sub-aperture lenses.

12. The split-aperture micro-projection device of claim 11, wherein the single image source is a 5.9mm diagonal half-length screen.

13. The Micro-aperture Micro-projection device of any one of claims 1 to 8, wherein the at least one image source is a Micro-LED screen or an OLED screen.

14. A method of making an aperture-dividing micro-projection device, comprising the steps of:

providing at least one image source; and

and arranging a plurality of sub-aperture lenses side by side on the light-emitting side of the at least one image source, wherein the plurality of sub-aperture lenses correspond to a plurality of image lights emitted by the at least one image source one to one and are used for modulating the corresponding image lights to project the image lights to the coupling-in area of the optical waveguide.

15. The method of manufacturing a split-aperture micro-projection device as claimed in claim 14, wherein in the step of providing at least one image source: and arranging a plurality of sub-image sources side by side to form the at least one image source, wherein the plurality of sub-image sources correspond to the plurality of sub-aperture lenses one to one, and the sub-aperture lenses are used for modulating the image light emitted by the corresponding sub-image sources to project to the optical waveguide.

16. The method of manufacturing a split-aperture micro-projection device as claimed in claim 14, wherein in the step of providing at least one image source: the at least one image source is a single image source, wherein the single image source corresponds to the plurality of sub-aperture lenses, and the single image source is configured to emit a plurality of image lights in one-to-one correspondence with the plurality of sub-aperture lenses.

17. The method of any of claims 14-16, wherein in the step of positioning a plurality of sub-aperture lenses side by side on a light emitting side of the at least one image source, wherein the plurality of sub-aperture lenses are in one-to-one correspondence with a plurality of beams of image light emitted via the at least one image source, for modulating the corresponding image light to project onto the incoupling area of the optical waveguide: the plurality of sub-aperture lenses are arranged along a direction perpendicular to a pupil expanding direction of the optical waveguide.