CN116157735A

CN116157735A - Projection module, assembly method thereof and near-to-eye display device comprising projection module

Info

Publication number: CN116157735A
Application number: CN202180058419.0A
Authority: CN
Inventors: 卢超; 李泓; 杜佳玮
Original assignee: Ningbo Sunny Opotech Co Ltd
Current assignee: Ningbo Sunny Opotech Co Ltd
Priority date: 2020-07-28
Filing date: 2021-07-06
Publication date: 2023-05-23
Also published as: WO2022022240A1; CN114002898A

Abstract

The invention relates to a projection module, an assembly method thereof and near-eye display equipment comprising the projection module. The projection module comprises a projection display device and a projection lens, wherein the projection display device comprises an illumination assembly and a display module with a display chip; the display module comprises a display module, a light conversion element, a display module and a light source, wherein the light conversion element is fixedly arranged on the rigid structural member, and a gap is reserved between the display module and the rigid structural member. The projection module has good optical axis consistency, and the projection image is not easy to distort and has good quality.

Description

Projection module, assembly method thereof and near-to-eye display device comprising projection module

Technical Field

The invention belongs to the technical field of projection display, and particularly relates to a projection module, an assembly method of the projection module and near-to-eye display equipment comprising the projection module.

Background

Near-eye display devices are receiving increasing attention, which may choose to use Virtual Reality (VR) technology and augmented Reality (Augmented Reality, AR) technology for projection imaging. Compared with VR, AR can construct virtual scenes based on the physical environment, and brings brand new experience to users.

The AR technique may use a waveguide sheet scheme (i.e., light source, projection lens plus waveguide sheet) or a conventional Birdbath scheme. The traditional Birdback scheme is difficult to be tolerated by consumers due to the problems of large volume, difficult further improvement of the angle of view, relatively poor experience and the like; in the scheme of using the waveguide sheet, only one waveguide sheet is mainly arranged in front of eyes of a user, so that the near-eye display device is smaller and more attractive, and the user experience is better. Accordingly, near-eye display devices using the waveguide sheet scheme are increasingly being received by users.

The near-eye display device using the waveguide sheet scheme mainly comprises a projection module (e.g. an optical machine) and a waveguide sheet. The projection module projects the image into the waveguide sheet, and the image is subjected to two-dimensional pupil expansion through the waveguide sheet so as to enter human eyes.

Disclosure of Invention

According to a first aspect of the present invention, there is provided a projection module comprising a projection display device and a projection lens, the projection display device comprising an illumination assembly and a display module with a display chip; the display module comprises a display module, a light conversion element, a display module and a light source, wherein the light conversion element is fixedly arranged on the rigid structural member, and a gap is reserved between the display module and the rigid structural member.

According to some additional or alternative embodiments, a connecting medium is provided in the gap, the connecting medium securing the display module to the rigid structure.

According to some additional or alternative embodiments, a first window is formed on one side of the rigid structural member, the display module is fixed at a window corresponding to the first window, and the display module and the light conversion element are respectively located on two sides of the first window.

According to some additional or alternative embodiments, the gap is in the range of 0.05mm or more and 1mm or less, or further in the range of 0.1mm or more and 0.6mm or less.

According to some additional or alternative embodiments, the gap is configured to: and determining the positioning of the display chip relative to the illumination assembly, so that the image projection image output by the projection lens meets the preset requirement under the determined positioning.

According to some additional or alternative embodiments, the projected image meeting predetermined requirements includes: the imaging definition of the projection image accords with corresponding preset requirements, the brightness uniformity of the projection image accords with corresponding preset requirements, and the virtual image of the projection image accords with corresponding preset requirements; or further comprising: the projected image is capable of entering the human eye in a substantially horizontal or substantially vertical orientation.

According to some additional or alternative embodiments, the display module is fixed to the rigid structure by a cured connecting medium in the gap, such that the display chip is fixed in the projection module based on the determined positioning.

According to some additional or alternative embodiments, the lighting assembly comprises a light source module;

the light conversion element is used for at least partially turning light rays emitted by the light source module to the display chip and/or at least partially turning light rays returned by the display chip to the projection lens of the projection module.

According to some additional or alternative embodiments, the first fenestration is configured to enable the display module to be positioned and mounted at the fenestration corresponding to the first fenestration from outside the rigid structure.

According to some additional or alternative embodiments, the display module includes a substrate for attaching the display chip;

and a connecting medium for fixing the display module on the rigid structural member is arranged between the edge part of the substrate and the step corresponding to the first window and used for supporting and positioning the substrate.

According to some additional or alternative embodiments, the thickness of the connecting medium is in the range of 0.05mm or more and 1mm or less, or further in the range of 0.1mm or more and 0.6mm or less.

According to some additional or alternative embodiments, the connection medium is configured to be able to seal the gap.

According to some additional or alternative embodiments, the connection medium has a thickness arrangement with a non-uniform thickness such that the display module is positioned obliquely with respect to the rigid structural member.

According to some additional or alternative embodiments, the projection module further comprises a support plate;

the support plate is provided with a glue drawing groove and a limiting structure, a connecting medium for fixedly mounting the rigid structural member is arranged in the glue drawing groove, and the limiting structure is arranged corresponding to the rigid structural member and used for limiting and mounting the rigid structural member on the support plate.

According to some additional or alternative embodiments, a second fenestration towards the light source module and a third fenestration towards the projection lens are also provided on an outer wall of the rigid structure;

the projection lens is positioned and installed on the third opening window, so that the projection lens is positioned and installed relative to the projection display device.

According to some additional or alternative embodiments, the projection lens is positionally mounted on the third fenestration by a connecting medium of a desired thickness arrangement and/or shape with the positioning of the projection lens relative to the rigid structure adjusted.

According to a second aspect of the present invention, there is provided a near-eye display device comprising: the projection module comprises a waveguide sheet, any one of the projection modules and a bracket;

wherein the waveguide sheet and the projection module are positioned and mounted on the bracket such that the center of the light projected by the projection module falls at the center of the coupling-in region of the waveguide sheet.

According to some additional or alternative embodiments, the support has receiving structure open thereon for at least partially receiving the waveguide sheet;

and the waveguide sheet is positioned and installed on the bracket through a connecting medium in the receiving structure under the condition that the positioning of the waveguide sheet relative to the bracket is regulated, so that the center of light rays projected by the projection module falls at the center of a coupling-in area of the waveguide sheet.

According to some additional or alternative embodiments, the connection medium is arranged bilaterally corresponding to the glue-drawing area of the waveguide sheet and is located between the waveguide sheet and the inner wall of the receiving structure; or the connecting medium is arranged on one side relative to the glue drawing area of the waveguide sheet and is positioned between the waveguide sheet and the inner wall of the receiving structure.

According to some additional or alternative embodiments, the inner wall of the receiving structure is provided with protrusions for increasing the surface area of the connecting medium in contact with the inner wall.

According to some additional or alternative embodiments, glue overflow grooves are provided on the inner wall of the receiving structure.

According to some additional or alternative embodiments, the unilateral gap between the waveguide sheet and the inner wall of the receiving structure is in the range of 0.25mm or more and 1mm or less.

According to some additional or alternative embodiments, a plurality of glue injection holes are provided in the bracket at positions corresponding to the glue drawing areas of the receiving structure and the waveguide sheet.

According to some additional or alternative embodiments, the projection module is located substantially on the out-coupling side of the waveguide sheet, or the projection module is located substantially on the opposite side of the out-coupling side of the waveguide sheet.

According to some additional or alternative embodiments, the projection module is mounted on the support in a position substantially vertically aligned with the incoupling region of the waveguide.

According to some additional or alternative embodiments, the projection module is mounted on the support with a position substantially parallel to the coupling-in region of the waveguide sheet, a refractive prism being arranged between the projection module and the coupling-in region of the waveguide sheet, the refractive prism being mounted with a position relative to the support such that the centre of the light rays projected by the projection module falls at the centre of the coupling-in region of the waveguide sheet after refraction by the prism.

According to some additional or alternative embodiments, the support is provided with an avoidance opening at a position corresponding to the coupling-in area of the waveguide sheet, the avoidance opening being used for avoiding the light rays projected by the projection module.

According to some additional or alternative embodiments, the support comprises a main support and a sub-support, wherein the main support and the sub-support are detachably and fixedly connected together and form a receiving structure for at least partially receiving the waveguide sheet, the waveguide sheet is positioned and mounted in the receiving structure between the main support and the sub-support, and the projection module is positioned and mounted on the left and right sides of the main support.

According to some additional or alternative embodiments, and the secondary support is fixedly arranged with respect to the primary support in a positioning manner avoiding the coupling-in region of the waveguide sheet.

According to some additional or alternative embodiments, the support is provided with marking points for positioning and mounting the waveguide sheet directly relative to the support by machine vision techniques.

According to a third aspect of the present invention, there is provided an assembling method of a projection module, comprising the steps of:

assembling an illumination assembly of the projection module, wherein a light conversion element of the illumination assembly is fixedly arranged on a rigid structural member;

Setting a display module with a display chip at a preset position of the projection module so as to leave an initial gap between the display module and the rigid structural member;

based on the preset position, adjusting the positioning of the display module relative to the lighting assembly until the projection image output by the projection lens of the projection module meets the preset requirement, and correspondingly, adjusting and determining the initial gap as the adjusted gap; and

and fixing the display module relative to the lighting assembly under the well-regulated positioning.

According to some additional or alternative embodiments, in the calibrating step, the positioning of the display chip with respect to the assembled lighting assembly is actively calibrated or adjusted using machine vision techniques.

According to some additional or alternative embodiments, the projected image meeting predetermined requirements includes: the imaging definition of the projection image accords with corresponding preset requirements, the brightness uniformity of the projection image accords with corresponding preset requirements, and the virtual image distance of the projection image accords with corresponding preset requirements; or further comprising: the projected image is capable of entering the human eye in a substantially horizontal or substantially vertical orientation.

According to some additional or alternative embodiments, the step of assembling the lighting assembly of the projection module comprises:

the light conversion element and the light source module of the lighting assembly are respectively and fixedly arranged in the first rigid structural member and the second rigid structural member; and

and fixedly mounting the first rigid structural member and the second rigid structural member on a support plate.

According to some additional or alternative embodiments, the step of assembling the lighting assembly of the projection module further comprises:

before the first rigid structural member and the second rigid structural member are fixedly installed on the supporting plate, the first rigid structural member and the second rigid structural member are positioned and connected with each other in a clamping manner.

According to some additional or alternative embodiments, the preset position is located outside the rigid structure to which the light-converting element is fixedly mounted;

in the adjusting step, the positioning of the display module with the display chip relative to the rigid structural member is adjusted from the outer side of the rigid structural member, so that the positioning of the display chip relative to the lighting assembly is adjusted.

According to some additional or alternative embodiments, the tuning includes one or more of:

Adjusting the inclination angle of the display module relative to the rigid structural member until the imaging definition of the projection image output by the projection lens of the projection module meets the corresponding preset requirement;

translating the display module relative to the rigid structural member in an xoy plane until the brightness uniformity of the projected image meets corresponding predetermined requirements, wherein the xoy plane is based on a direction perpendicular to light rays emitted from a light conversion element of the illumination assembly to the display chip;

translating the display module relative to the rigid structural member along a z direction until a virtual image distance of the projected image meets corresponding preset requirements, wherein the z direction is a direction of light rays emitted from a light conversion element of the illumination assembly to the display chip;

the display module is rotated relative to the rigid structure in the xoy plane until the projected image is able to enter the human eye in a substantially horizontal or substantially vertical orientation.

According to some additional or alternative embodiments, in the fixing step, the substrate to which the display chip is attached is fixed with respect to the rigid structural member of the lighting assembly to which the light conversion element is fixedly mounted, by a connection medium.

According to some additional or alternative embodiments, in the step of adjusting, an initial gap between the display module and the rigid structure is determined by adjusting the positioning of the display chip relative to the assembled lighting assembly to obtain the adjusted gap; wherein the connecting medium is arranged in the gap after adjustment.

According to a fourth aspect of the present invention, there is provided a method for assembling a projection module, comprising the steps of:

assembling a projection display device of the projection module;

setting a projection lens of the projection module at a preset position of the projection module;

based on the preset position, adjusting the positioning of the projection lens relative to the projection display device until the projection image output by the projection lens of the projection module meets the preset requirement; and

and fixing the projection lens relative to the projection display device under the well-regulated positioning.

According to some additional or alternative embodiments, in the adjusting step, the positioning of the projection lens with respect to the assembled projection display device is actively adjusted or adjusted using machine vision techniques.

According to some additional or alternative embodiments, the projected image meeting predetermined requirements includes: the imaging definition of the projection image meets corresponding preset requirements, the brightness uniformity of the projection image meets corresponding preset requirements, and the virtual image of the projection image meets corresponding preset requirements.

According to some additional or alternative embodiments, the step of assembling the projection display device of the projection module comprises:

the light conversion element and the light source module of the lighting assembly are respectively and fixedly arranged in the first rigid structural member and the second rigid structural member;

fixedly mounting the rigid structural member and the second rigid structural member on a support plate; and

and fixedly mounting the display chip on the first rigid structural member.

According to some additional or alternative embodiments, the step of assembling the projection display device of the projection module further comprises:

before the rigid structural member and the second rigid structural member are fixedly mounted on the support plate, the rigid structural member and the second rigid structural member are positioned and connected with each other in a clamping manner.

In the adjusting step, the positioning of the projection lens relative to the rigid structural member is adjusted from the outer side of the rigid structural member, so that the positioning of the projection lens relative to the projection display device is adjusted.

adjusting the inclination angle of the projection lens relative to the rigid structural member fixedly provided with the light conversion element until the imaging definition of the projection image output by the projection lens meets the corresponding preset requirement;

translating the projection lens relative to the rigid structural member in an xoy plane until the brightness uniformity of the projected image meets corresponding predetermined requirements, wherein the xoy plane is based on a direction perpendicular to light rays emitted from a light conversion element of the illumination assembly to the display chip;

and translating the projection lens relative to the rigid structural member along the z direction until the virtual image of the projection image meets corresponding preset requirements, wherein the z direction is the direction of light rays emitted from the light conversion element of the illumination assembly to the display chip.

According to some additional or alternative embodiments, in the fixing step, the projection lens is fixed with respect to a rigid structural member of the illumination assembly to which the light-converting element is fixedly mounted, by means of a connecting medium.

According to some additional or alternative embodiments, in the adjusting step, a gap between the projection lens and a rigid structural member to which the light conversion element is fixedly mounted is determined by adjusting a positioning of the projection lens with respect to the assembled projection display device; wherein the connection medium is disposed in the gap.

According to a fifth aspect of the present invention, there is provided a method of assembling a near-eye display device, comprising the steps of:

positioning and mounting the projection module on the bracket;

adjusting the positioning of the waveguide sheet relative to the bracket until the center of the light projected by the projection module falls at the center of the coupling-in area of the waveguide sheet; and

and fixing the waveguide sheet relative to the bracket under the well-regulated positioning.

The above features, operation and advantages of the present invention will become more apparent from the following description and the accompanying drawings.

Drawings

The above and other objects and advantages of the present invention will become more fully apparent from the following detailed description taken in conjunction with the accompanying drawings, in which identical or similar elements are designated by the same reference numerals.

Fig. 1 is a schematic view of a basic structure of a projection module according to an embodiment of the present invention, in which a receiving camera used in a calibration process of the projection module is shown.

Fig. 2 is a schematic diagram of a basic structure of the projection module of the embodiment of fig. 1 from another perspective.

Fig. 3 is a schematic structural diagram of a first rigid structure of the projection module of the embodiment shown in fig. 1, and a light conversion element and a projection lens fixedly mounted thereon.

Fig. 4 is a schematic structural diagram of the first rigid structure of the projection module of the embodiment shown in fig. 1, and the light conversion element and the projection lens fixedly mounted thereon, and the display module.

Fig. 5 is a schematic diagram of an optical path of the projection module according to the embodiment shown in fig. 1.

Fig. 6 is a schematic diagram of a further optical path of the projection module according to the embodiment shown in fig. 1.

Fig. 7 is a schematic view of an optical path of a projection module according to another embodiment of the invention.

Fig. 8 is a flowchart of an assembling method of a projection module according to an embodiment of the invention.

Fig. 9 is a flowchart of an assembling method of a projection module according to still another embodiment of the present invention.

Fig. 10 is a schematic structural view of a near-eye display device according to a first embodiment of the present invention.

Fig. 11 is a schematic structural view of the near-eye display device of the embodiment shown in fig. 10 from another perspective.

Fig. 12 is a top view of the near-eye display device of the embodiment shown in fig. 10, further showing an enlarged view of a partial area a with respect to the receiving structure.

Fig. 13 is a schematic structural view of a waveguide sheet used for the near-eye display device according to the first embodiment of the present invention, wherein fig. 13 (a) and 13 (b) show the waveguide sheet from different viewing angles, respectively.

Fig. 14 is a schematic structural view of a near-eye display device according to a second embodiment of the present invention.

Fig. 15 is a schematic structural view of the near-eye display device of the embodiment shown in fig. 14 from another perspective.

Fig. 16 is a top view of the near-eye display device of the embodiment shown in fig. 14, further showing an enlarged view of a partial region B with respect to the receiving structure.

Fig. 17 is a schematic diagram of a projection module for positioning and mounting the near-eye display device of the embodiment of fig. 14.

Fig. 18 is a schematic structural view of a waveguide sheet used for the near-eye display device according to the second embodiment of the present invention, wherein fig. 18 (a) and 18 (b) show the waveguide sheet from different viewing angles, respectively.

Fig. 19 to 21 are schematic structural views of a near-eye display device according to a third embodiment of the present invention.

Fig. 22 is a schematic structural view of a near-eye display device according to a fourth embodiment of the present invention.

Fig. 23 is a flowchart of an assembling method of a near-eye display device according to an embodiment of the present invention.

Detailed Description

The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which illustrative embodiments of the invention are shown. This invention may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. The above-described embodiments are presented in order to provide a thorough and complete disclosure of the present invention, and to provide a more complete and accurate understanding of the scope of the present invention.

In the following description, not all of the various components shown in the figures are depicted for clarity and conciseness of description. The various components are shown in the drawings to provide those of ordinary skill with a fully enabling disclosure of the present invention. The operation of many of the components will be familiar and apparent to those skilled in the art within the scope of this invention.

Herein, the terms of orientation of "upper", "lower", "left", "right", "front", "rear" are defined with respect to the orientation of the projection module/near-eye display device in the drawings after installation and use or with respect to the orientation shown in the drawings, and it should be understood that these directional terms are relative concepts used for the description and clarification of the relative terms, which may be changed accordingly depending on the change in the orientation in which the opening and closing device is placed.

The applicant has also noted that the projection module generally comprises a display device and a projection lens, the relative positions of which directly determine the quality of the projected image, however, assembly tolerances are also not necessarily present when the display device and the projection lens are assembled together, so that the image projected by the projection module may appear distorted when reaching the human eye, etc. In addition, assembly tolerances are inevitably present in the assembly process of a plurality of components of the display device (such as the light source module, the display chip and the optical element for splitting light), so that distortion is also easily caused in the projection image of the projection module.

For ease of understanding and description, in the relevant figures of the projection module 10, the x-direction, the y-direction, and the z-direction are defined based on the orientation of the projection module, where the x-direction corresponds to the direction of light from the light conversion element toward the projection lens, the z-direction corresponds to the direction of light from the light conversion element toward the display chip, and the y-direction is substantially perpendicular to the plane xoz.

The following illustrates a projection module 10 according to an embodiment of the invention with reference to fig. 1 to 4. The projection module 10 of the following example may be actively calibrated and then assembled prior to installation on a near-eye display device (e.g., the near-eye display device 200 of fig. 8), so that the projection image (which may be projected onto a waveguide sheet) output by the projection module 10 may be of good image quality (e.g., with little distortion) against assembly tolerances, etc., of the projection module 10, such as during assembly.

Referring to fig. 1 and 2, a projection module 10 according to an embodiment of the present invention includes a projection display device 11 and a projection lens 13, and the projection display device 11 may include an illumination assembly 111, a display module 113 with a display chip 1130. The projection module 10 or the illumination assembly 111 may further comprise a first rigid structure 121. For ease of understanding, the display module 113 is illustrated in fig. 1-4 as being separately disposed with respect to the first rigid structure 121, and it will be appreciated that the display module 113 is positioned and secured to the first rigid structure 121 after the projection module 10 is assembled.

The illumination assembly 111 may include a light source module 1110 and at least one light conversion element 1112, and the light conversion element 1112 may at least partially convert light emitted from the light source module 1110 to the display chip 1130 (see fig. 5, in which S light of the light emitted from the light source module 1110 is reflected to the LCOS chip) or may at least partially convert light returned from the display chip 1130 to the projection lens 13 (see fig. 6, in which S light for forming a projection image is reflected to the projection lens 13), so that the light conversion element 1112 may have a light splitting and combining function, which may be, but not limited to, a PBS (Polarization Beam Splitter, polarization splitting) prism as exemplified in fig. 5 and 6, which may also be, for example, a TIR (Total Internal Reflection total internal reflection) prism as illustrated in fig. 7. For example, the light source module 1110 may include a light source, or may further include a light equalizing element (such as a collimator) corresponding to the light source, where the light emitted by the light source enters the light conversion element 1112 after passing through the light equalizing element; further, the light sources may be two or three (e.g., red light source, blue light source, color filter light source), and three corresponding light source devices may be disposed in one structural member, and then combined by a color combining optical element to form an RGB light source. It will be appreciated that the specific arrangement of the light source module 1110 is not limiting.

The display chip 1130 of the display module 113 may be a passive light emitting display, which may be, for example, an LCOS (Liquid Crystal on Silicon ) chip (as shown in fig. 5 and 6) or a DLP (Digital Light Processing, digital optical processing) chip (as shown in fig. 7) or the like, and the display module 113 further includes a substrate 1131 for mounting the display chip 1130, wherein the display chip 1130 may be pre-mounted inside the substrate 1131, and the positioning of the display chip 1130 and the substrate 1131 with respect to, for example, the first rigid structure 121 may be adjusted together during assembly.

As further shown in fig. 1 to 4, the projection module 10 or the illumination assembly 111 further includes a second rigid structure 122, and a support plate 123 is provided corresponding to the first rigid structure 121, and the first rigid structure 121, the second rigid structure 122 and the support plate 123 are used to position the respective optical elements of the illumination assembly 111 so that the optical paths of the illumination assembly 111 are fixed after being assembled.

Wherein the first and second rigid

structural members

121 and 122 may be fixedly mounted on the support plate 123; the first rigid structure 121 may be generally configured as a hexahedron, and at least the light conversion element 1112 (see fig. 3 and 4) may be accommodated and fixed in the inner cavity of the first rigid structure 121. In an embodiment, the first rigid structure 121 may also be used to position the display module 113 and/or the projection lens 13; the second rigid structure 122 may be generally configured as a hexahedron, and the light source module 1110, for example, a light source of the light source module 1110, a collimator lens, etc., may be received and fixed in the inner cavity of the second rigid structure 122.

It will be appreciated that the first and second rigid

structural members

121, 122 are separate from each other prior to assembly, and they are positioned and mounted to each other; in other embodiments, the first and second

rigid structures

121 and 122 may also be integrally provided.

Fig. 5 shows a schematic diagram of an optical path of the projection module of the embodiment of fig. 1. Referring to fig. 5, an lcos chip represents a display chip 1130, which may modulate a light source to form an image, a PBS prism represents a light conversion element 1112, and a light source and collimator represents a light source module 1110; in this embodiment, the LCOS chip, PBS prism and projection lens 13 form a straight optical path that can be formed by fixing their positions during assembly so that they lie along a generally straight line. In the projection imaging process, light rays emitted by a light source enter a PBS prism through a collimating lens, S light of the light rays can be turned and reflected to an LCOS chip through the PBS prism, the LCOS chip can convert the S light received by different pixels of the LCOS chip into P light for forming a projection image in a proportion controllable manner, and the P light passes through the PBS prism in a straight line and is projected to a projection lens 13. Thus, the projection lens 13 can form, for example, a color projection image to be projected.

Fig. 6 shows a schematic diagram of a further optical path principle of the projection module of the embodiment of fig. 1. Referring to fig. 6, an lcos chip represents a display chip 1130, which may modulate a light source to form an image, a PBS prism represents a light conversion element 1112, a light source and a collimator mirror represent a light source module 1110, and a mirror of the projection module 10, which is not specifically shown in fig. 1, is also shown; in this embodiment, the LCOS chip, PBS prism and projection lens 13 form a straight optical path that can be formed by fixing their positions during assembly so that they lie along a generally straight line. In projection imaging, light from a light source enters a PBS prism via a collimator lens, S light of the light is reflected to a wave plate (not shown) and a total reflection mirror in a turning way through the PBS prism, the wave plate converts the S light into P light, then the P light is reflected to the PBS prism by the total reflection mirror, the P light passes through the PBS prism and is projected to an LCOS chip, the LCOS chip converts the P light received by different pixels into S light for forming a projection image in a proportion controllable way, and the S light for forming the projection image is reflected to a projection lens 13 in a turning way through the PBS prism. Thus, the projection lens 13 can form, for example, a color projection image to be projected.

As can be seen from the light paths shown in fig. 5 or fig. 6, the projection module 10 has complex light paths and various internal devices, besides the precision errors of manufacturing various devices, errors are unavoidable in the assembly process of numerous devices, and more importantly, the display chip 113 modulates the incident light to form an image, so that the assembly precision of the display chip is easy to directly relate to the quality of the projection pattern, the requirement of the display chip 113 on the angle of the incident light is high, and the requirement is within a certain range, otherwise, the projected image is easy to generate negative effects (such as aberration or chromatic aberration, etc.).

To overcome problems such as image distortion caused by assembly errors, in one embodiment, a gap (not shown) is provided between display module 113 and first rigid structure 121, which gap reflects the positioning of display chip 1130 relative to illumination assembly 111; in the assembled projection module 10, a connecting medium (e.g. a cured gel) is provided in the gap, which secures the display module 113 to the first rigid structure 121.

It will be appreciated that this gap is movable before the attachment medium is provided (e.g., before the glue is drawn) to allow adjustment of the positioning of the display module 113 relative to the first rigid structure 121, and is determined and fixed after the attachment medium is provided (e.g., after the glue is cured), the positioning of the display module 113 relative to the first rigid structure 121 is fixed, i.e., the positioning of the display chip 1130 relative to the illumination assembly 111 is fixed. Thus, the presence of this gap will allow the positioning of display module 113/display chip 1130 to be actively adjusted after illumination assembly 111 has been substantially assembled until the projected image output by projection lens 13 meets predetermined requirements; the gap reflecting the good positioning of the display module 113 is easily fixed by a connection medium such as a gel, so that the adjusted positioning of the display module 113/the display chip 1130 is always reflected in the projection module 10 and used. Therefore, the projection module 10 having such a gap easily overcomes the unavoidable internal tolerance inside the illumination assembly 111 to achieve substantial uniformity of the optical axis between the projection lens 13 and the display chip 1130, and even to achieve substantial uniformity of the optical axis between the projection lens 13, the light conversion element 1112, and the display chip 1130.

The gap between the display module 113 and the first rigid structure 121 may be determined and fixed, for example, in the following manner (i.e., first manner): actively adjusting the positioning of the display module 113 as a whole relative to the first rigid structure 121 then fixedly mounts the display module 113 on the first rigid structure 121, for example by gluing.

In other embodiments, there is a gap (not shown) between the projection lens 13 and the first rigid structure 121, which reflects the positioning of the projection lens 13 relative to the projection display device 11; in the assembled projection module 10, a connecting medium (e.g., a cured gel) is disposed in the gap, and the connecting medium fixes the projection lens 13 to the first rigid structure 121. It will be appreciated that the gap is movable before the attachment medium is provided (e.g. before the glue is drawn) to allow adjustment of the positioning of the projection lens 13 relative to the first rigid structure 121, and that the gap is determined and fixed after the attachment medium is provided (e.g. after the glue is cured), i.e. the positioning of the projection lens 13 relative to the first rigid structure 121 is fixed, i.e. the positioning of the projection lens 13 relative to the assembled projection display device 11 is fixed. Thus, the presence of this gap will allow the positioning of the projection lens 13 to be actively adjusted after the projection display device 11 has been substantially assembled until the projected image output by the projection lens 13 meets the predetermined requirements; the gap reflecting the good positioning of the display module 113 is easily fixed by a connection medium such as a colloid, so that the positioning of the adjusted projection lens 13 is always reflected in the projection module 10 and used. Therefore, the projection module 10 having such a gap easily overcomes the unavoidable internal tolerances (including the mounting tolerance of the display module 113) inside the projection display device 11 to achieve substantial uniformity of the optical axis between the projection lens 13 and the display chip 1130, and even to achieve substantial uniformity of the optical axis between the projection lens 13, the light conversion element 1112, and the display chip 1130.

The gap between the projection module 10 and the first rigid structure 121 may be determined and fixed, for example, in the following manner (i.e., the second manner): actively adjusting the positioning of the entire projection lens 13 relative to the first rigid structure 121 and then fixedly mounting the projection lens 13 on the first rigid structure 121, for example, by a glue.

Since the optical axis between the projection lens 13 and the display chip 1130 is uniform in the assembled projection module 10, it is advantageous to form a high-quality projection image, for example, a projection image meeting predetermined requirements.

In the above-described positioning process of the display chip 1130 or the projection lens 13, a receiving camera 91 as shown in fig. 1 may be used to help determine the positioning; the receiving camera 91 may be fixedly disposed at a light output position of the projection module 10 to receive the projection image; by the received projection image, the relative position of the display chip 113 and the illumination assembly 111 can be adjusted in real time (the display chip 113 is fixedly mounted), or the relative position of the projection lens 13 and the projection display device 11 can be adjusted in real time.

It will be appreciated that the predetermined requirement for projecting the image may be determined in advance, for example, in a projection module having good assembly accuracy and good optical axis consistency between the projection lens 13 and the display chip 1130; in the case where the projection image output by the projection lens 13 (which can be determined and the quality thereof acquired by the receiving camera 91) meets a predetermined requirement, the optical axis between the projection lens 13 and the display chip 1130 is determined to be substantially uniform. Specifically, the projected image meeting the predetermined requirements includes: the imaging definition of the projection image accords with corresponding preset requirements, the brightness uniformity of the projection image accords with corresponding preset requirements, and the virtual image distance of the projection image accords with corresponding preset requirements; or further comprising: the projected image can enter the human eye in a substantially horizontal or substantially vertical orientation (in the case where, for example, the display module 113 can be rotated in the xoy plane relative to the first rigid structure 121).

As shown in fig. 1 to 4, the first rigid structure 121 may have a hexahedral structure as a whole, in which at least three sides have windows, a side facing the light source module 1110 has a second window 126 (i.e., a light incident window), a side facing the projection lens 13 has a third window 127 (i.e., a light exit window for outputting outgoing light to the projection lens), and a side facing the display module 113 has a first window 124 (display window). Both the light entrance window and the light exit window are arranged in the x-direction and the display window may be open towards the z-direction.

The outer side of the first window 124 may be provided with a step 1212 (see fig. 4), the step 1212 is used to support and position the display module 113, the display module 113 may be well positioned with respect to the illumination assembly 111 after being actively adjusted (a gap between the display module 113 and the first rigid structure 121 is determined), and may be fixed at the window of the first window 124 of the first rigid structure 121 by a glue, wherein the step 1212 is provided with the glue, and the step of the first rigid structure 121 and the substrate 1131 of the display module 113 are fixedly connected by the glue, so that the gap between the display module 113 and the first rigid structure 121 described above may be formed. The display module 113 and the light conversion element 1112 are respectively located on, for example, the upper and lower sides of the first window 124.

The substrate 1131 may be, but not limited to, a ceramic or metal substrate, which has high strength and heat dissipation performance. In the positioning process of the adjustment display module 113, the display module 113 can be fixed on an external adjusting mechanism in a clamping or sucking manner, and the ceramic or metal substrate with larger strength can not easily deform when being clamped or sucked by the adjusting mechanism. Optionally, the substrate 1131 further includes a circuit board, and the display chip 1130 (e.g., LCOS chip) is electrically connected to the circuit board.

The fixed gap between the display module 113 and the first rigid structural member 121 is in a range of 0.05mm or more and 1mm or less; alternatively, when the optical axis consistency of the optical components of the illumination assembly 111 is high, the fixed gap between the display module 113 and the first rigid structure 121 is in a range of 0.1mm or more and 0.6mm or less. Correspondingly, the thickness of the connection medium (e.g., colloid) provided on the step 1212 is in a range of 0.05mm or more and 1mm or less, or further, in a case where the optical axis uniformity of each optical element of the illumination assembly 111 is high, the thickness of the connection medium (e.g., colloid) provided on the step 1212 is in a range of 0.1mm or more and 0.6mm or less.

It will be appreciated that the thickness of the connecting medium (e.g. glue) or the fixed gap between the display module 113 and the first rigid structure 121 may be arranged unequally within the above-mentioned ranges to ensure various oblique positioning of the display module 113 relative to the first rigid structure 121.

In an embodiment, the gel between the substrate 1131 and the first rigid structure 121 is shaped to seal all gaps between the substrate 1131 and the first fenestration 124; for example, the gel may be provided in a ring shape, so that the inner space of the first rigid structural member 121 may be sealed. In this way, unwanted stray light and dust can be avoided from entering the interior of the first rigid structure 121.

Further, at least a mounting wall for mounting the projection lens 13 is provided on the third window 127. In the first manner, the projection lens 13 may be fixed on the third opening 127 by a connecting medium such as glue before the display module 113, and the display module 113 is positioned and mounted on the first opening 124 from the outside of the first rigid structure 121 (for example, on the exposed step 1212 of the first rigid structure 121), so as to achieve accurate positioning and mounting of the display chip 1130 relative to the illumination assembly 111.

It should be noted that, in the miniature projection module 10, not only the display chip 1130 and other optical elements are small in size, but also their installation space is small, so it is generally difficult to perform internal adjustment to achieve high optical axis consistency; the projection module 10 of the above embodiment can fix the display module 113 on the outer side of the first rigid structural member 121 and fix the light conversion element 1112 on the inner side of the first rigid structural member 121, so that the display module 113 can be actively adjusted from the outer side of the first rigid structural member 121, which is beneficial to facilitating adjustment and obtaining accurate positioning results or gaps, and also facilitating fixed installation (such as fixing the gap between the display module 113 and the first rigid structural member 121) after the positioning is adjusted; thereby being beneficial to obtaining better consistency of optical axes and improving the quality of projection images.

With continued reference to fig. 1 and 2, a surface of the second rigid structure 122 facing the light-converting element 1112 is also provided with a window for incidence of light emitted by the light source. The first rigid structure 121 and the second rigid structure 122 may be positioned and connected to each other before the first rigid structure 121 is mounted on the supporting plate 123, so that the mounting accuracy of the second rigid structure 122 and the first rigid structure 121 is improved, and the consistency of the optical axes of the light source, the collimating mirror, the PBS prism and other optical elements is improved.

In an embodiment, the second rigid structure 122 and/or the first rigid structure 121 may be provided with chamfers or steps or the like at the two structure contact areas to form the glue-drawing area 233, by means of the glue-drawing area 233, the second rigid structure 122 and the first rigid structure 121 may be connected to each other before they are mounted on the support plate 123. Further, referring to fig. 1 and 2, the first rigid structure 121 and the second rigid structure 122 may also be connected together by a snap-fit manner. Specifically, the second rigid structural member 122 has a pair of protruding portions 124a on both side walls thereof, the protruding portions 124a being provided so as to protrude toward the first rigid structural member 121 in the x direction, and correspondingly, the first rigid structural member 121; a pair of concave portions 124b are arranged on the two side walls, and the concave portions 124b are concave inwards to receive the protruding portions 124a; by configuring the shapes of the protruding portion 124a and the recessed portion 124b, they can be made to form the engagement structure 124; the second rigid structural member 122 and the first rigid structural member 121 are positioned and connected through the clamping structure 124, so that the positioning precision and the connecting strength between the second rigid structural member 122 and the first rigid structural member 121 are improved. It will be appreciated that the second rigid structure 122 and the first rigid structure 121 may be further fixedly connected after being snapped together, such as by glue.

It will be appreciated that the support plate 123 serves primarily a fixing and reinforcing function in the case where the second rigid structural member 122 and the first rigid structural member 121 are connected to each other. In other embodiments, the second rigid structure 122 and the first rigid structure 121 may be fixedly connected to each other during the process of mounting them to the support plate 123, and the support plate 123 may also function as a positioning connection.

In one embodiment, as shown in fig. 2, the support plate 123 is provided with a glue drawing groove 1231 and a limiting structure 1232; the glue drawing groove 1231 may be a through structure, and a connecting medium such as a glue may be disposed in the glue drawing groove 1231, where the glue may be used to fixedly mount the second rigid structural member 122 and/or the first rigid structural member 121; the limiting structure 1232 is mainly disposed corresponding to the first rigid structural member 121, and is used for limiting and installing the first rigid structural member 121 on the supporting plate 123. The limiting structure 1232 may specifically include one or more pairs of limiting holes, and correspondingly, a corresponding limiting structure including one or more pairs of limiting posts 1212 may be disposed at the bottom of the first rigid structure 121. In other embodiments, the stop structure 1232 may also be disposed corresponding to the second rigid structure 122 (e.g., a corresponding stop post may also be disposed on the second rigid structure 122). The lighting assembly 111 (including the first rigid structure 121 and the second rigid structure 122) is integrally positionally mounted on the support plate 123 in a spacing manner by the spacing structure of the above embodiment.

It should be noted that the positioning and mounting of the display chip 1130 with respect to the illumination assembly 111 or the positioning and mounting of the projection lens 13 with respect to the projection display device 11 described in the above examples may be performed after the first rigid structural member 121 and the second rigid structural member 122 are integrally mounted on the support plate 123, so that, by actively adjusting the positioning of the display chip 1130 with respect to, for example, the first rigid structural member 121/actively adjusting the positioning of the projection lens 13 with respect to, for example, the first rigid structural member 121, the mounting errors of the respective devices inside the illumination assembly 111/display device 11, etc. that have been substantially assembled, will be taken into consideration during the active adjustment, and the problem of poor optical axis consistency of the projection lens 13 and the display chip 1130 due to such errors will be effectively overcome.

Fig. 7 is a schematic view of an optical path of a projection module according to another embodiment of the invention. In the projection module of this embodiment, the display chip 1130 may be a DMD chip, and the light conversion element 1112 is correspondingly configured as a TIR prism.

The following describes an exemplary assembly method of the projection module 10 according to an embodiment of the present invention with reference to fig. 8.

First, in step S801, the illumination assembly 111 of the projection module 10 is assembled, and in particular, the light conversion element 1112 of the illumination assembly 111 is fixedly mounted on the rigid structure 121.

In this step, the optical device or the like of the illumination assembly 111 may be assembled using the first rigid structural member 121, the second rigid structural member 122 or the like. First, various components required for assembly are provided, such as a first rigid structural member 121, a second rigid structural member 122, a support plate 123, a light source, a collimator mirror, a light conversion element 1112, and the like; further, attaching the light source and the collimator lens into the inner cavity of the second rigid structure 122, and attaching the light conversion element 1112 into the inner cavity of the first rigid structure 121; alternatively, the projection lens 13 may be attached to the first rigid structure 121, wherein the projection lens 13 may be disposed at the light emitting position of the light converting element 1112, for example, at the window opening of the third window opening 127 positioned and mounted on the first rigid structure 121. Then, the second rigid structural member 122 and the first rigid structural member 121 may be positioned and connected to each other in a clamping manner by the clamping structure 124, and fixed by a connecting medium such as glue.

Step S801 may further include integrally positioning and mounting the first rigid structure 121 and the second rigid structure 122 that are fixedly connected together on the supporting plate 123, for example, integrally positioning and mounting the first rigid structure 121 and the second rigid structure 122 on the supporting plate 123 by using the spacing posts 1212 and the glue in the glue slot 1231.

It should be noted that, in the step S801, two separate structural members (i.e., the first rigid structural member 121 and the second rigid structural member 122) are adopted, and the light source module 1110 and the light conversion element 1112 may be disposed on the two structural members, so that the corresponding components of the lighting assembly 111 may be accurately attached to the corresponding structural members by using the machine vision technology, which is beneficial to improving the assembly accuracy of the lighting assembly 111, and improving the consistency of the optical axes between the optical elements inside the lighting assembly 111.

Further, in step S802, the display module 113 with the display chip 1130 is disposed at a preset position of the projection module 10, so that an initial gap is left between the display module 113 and the rigid structure 121.

It should be noted that, the preset position may enable the rough positioning of the display module 113 relative to the first rigid structure 121, and the preset position does not take into consideration the assembly tolerance generated in step S801, and when the display module 113 is placed in the preset position, the projection image generated by the projection module 10 is easily distorted, for example.

The predetermined position may be outside the first rigid structure 121; for a plurality of projection modules 10, the preset position of the display module 113 may be uniformly determined with respect to the first rigid structure 121; the display module 113 may be placed at the preset position by means of an external device and controlling the position of the component of the external device to which the display module 113 is attached.

Further, in step S803, the positioning of the display module 113 relative to the substantially assembled lighting assembly 111 is adjusted based on the preset position until the projection image output by the projection lens 13 of the projection module 10 meets the predetermined requirement, and accordingly, the initial gap is adjusted and determined as the adjusted gap.

In this step S803, the display chip 1130 is fixed on the substrate 1131 in advance, and thus the adjustment of the positioning of the display chip 1130 can be achieved by the adjustment of the positioning of the display module 113 with respect to the illumination assembly 111 (e.g., the first rigid structure 121).

In this step S803, the positioning of the display module 113 with respect to the lighting assembly 111 (e.g., the first rigid structure 121) may be continuously adapted using the corresponding assembly system until the projected image received in the receiving camera 91 meets the predetermined requirements.

In an embodiment, the assembly system may include a six-axis platform, where the display module 113 is fixed to the six-axis platform by a clamping jaw or a suction nozzle, and the six-axis platform may actively control the orientation of the display module 113 relative to the first rigid structure 121 or the light conversion element 1112, so as to facilitate active adjustment.

In the calibration process, the projection module 10 is powered on and projects a specific pattern, and the relative position between the display module 113 and the illumination assembly 111 is adjusted in real time according to the image information received by the receiving camera 91, where the adjustment direction may include six-axis adjustment (for example, translation in x/y/z direction, rotation around z/y/z direction, and a plane perpendicular to the central light of the display chip 1130 is defined as xoy plane), until the pattern received by the receiving camera 91 meets a predetermined standard, and the relative position between the display module 113 and the illumination assembly 111 at this time is determined. When determining whether the image received by the receiving camera 91 meets the standard, the direction, the scale, the angle, etc. to be adjusted by the display chip 1130 may be obtained by using the image aberration obtained by computer calculation; parameters such as a relative inclination angle, a translation amount, and a distance between the display chip 1130 and the light conversion element 1112 (or the projection lens 13) can be obtained by receiving the resolution data of a series of images received by the camera 91; further, the six-axis platform can adjust the relative position between the display chip 1130 and the light conversion element 1112 based on these parameters.

During the calibration process, the positioning adjustment of the display module 113 may include the following actions:

adjusting the inclination angle of the display module 13 relative to the first rigid structural member 121 until the imaging definition of the projection image output by the projection lens 13 of the projection module 10 meets the corresponding preset requirement;

translating the displayed module 113 relative to the first rigid structure 121 in an xoy plane based on a direction perpendicular to light rays emitted from the light conversion element 1112 of the illumination assembly 111 toward the display chip 1130 (as shown in fig. 1) until the brightness uniformity of the projected image meets the respective predetermined requirements;

translating the display module 113 relative to the first rigid structure 121 along a z-direction until a virtual image distance of the projected image meets a corresponding predetermined requirement, wherein the z-direction is a direction of light emitted from the light conversion element 1112 of the illumination assembly 111 to the display chip 1130 (as shown in fig. 1);

the display module 113 is rotated in the xoy plane relative to the first rigid structure 121 until the projected image can enter, for example, the human eye or the receiving camera 91 in a substantially horizontal or substantially vertical orientation.

It will be appreciated that since the light-converting element 1112 has been fixedly disposed in the first rigid structure 121, the positioning of the alignment display module 113/display chip 1130 relative to the first rigid structure 121 also indicates the positioning of the alignment display module 113/display chip 1130 relative to the light-converting element 1112.

In the step S803, the positioning of the display module 113 with the display chip 1130 relative to the first rigid structure 121 can be adjusted from the outside of the first rigid structure 121 by means of, for example, a six-axis platform, which is beneficial to facilitating adjustment and obtaining accurate positioning results, and also facilitating fixing installation after the positioning is adjusted; thereby being beneficial to obtaining better consistency of optical axes and improving the quality of projection images.

In step S803, the positioning of display chip 1130 with respect to substantially assembled lighting assembly 111 may be actively calibrated, or the positioning of display chip 1130 with respect to substantially assembled lighting assembly 111 may also be adjusted using machine vision techniques.

Through the teaching process of step S803, the display module 113 is further accurately positioned with respect to the first rigid structural member 121, that is, the display chip 1130 is further accurately positioned with respect to the light conversion element 1112 and the projection lens 13 fixed on the first rigid structural member 121, so that the problems caused by assembly errors of the illumination assembly 111 and tolerances of the elements are overcome, and the consistency of the optical axes among the display chip 1130, the light conversion element 1112 and the projection lens 13 is good.

Further, in step S804, the display module 113 is fixed relative to the illumination assembly 111 under the adjusted positioning.

It will be appreciated that the adjusted positioning of step S803 may be determined or recorded, and in particular the adjusted positioning may indicate that under the positioning condition, the imaging sharpness of the projected image meets the respective predetermined requirement, the brightness uniformity of the projected image meets the respective predetermined requirement, the virtual image distance of the projected image meets the respective predetermined requirement, and the projected image is capable of entering the human eye in a substantially horizontal or substantially vertical orientation. With the aligned positioning, the aligned gap between the display module 113 and the first rigid structure 121 is determined.

In step S804, the substrate 1131 to which the display chip 1130 is attached may be fixed to the first rigid structure 121 by a connection medium such as a glue, and the glue is placed in the gap between the display module 113 and the first rigid structure 121, for example, the glue is applied on the step 1212 and cured, so as to seal the first window 124.

The assembly method of the above embodiment can form the projection module 10 of an embodiment of the present invention after the assembly is completed, and the active adjustment process of step S803 can overcome the assembly error or the self tolerance of the lighting assembly element that has occurred in the assembly process of step S801, so that the optical axes among the display chip 1130, the light conversion element 1112 and the projection lens 13 are substantially consistent, and the quality of the projection image is greatly improved.

A specific assembly method of the projection module 10 according to another embodiment of the present invention is described below with reference to fig. 9.

First, in step S901, the projection display device 11 of the projection module 10 is assembled.

Note that this step S901 is similar to step S801 of the embodiment shown in fig. 8; however, with respect to step S801, this step S901 also fixedly mounts the display module 113 at the window of the first window 124 of the first rigid structure 121 based on the preset position of step S802, for example, which is difficult to achieve the accurate positioning in step S803 above.

Specifically, step S901 includes: fixedly mounting the light conversion element 1112 and the light source module 1110 of the lighting assembly 111 inside the first rigid structural member 121 and the second rigid structural member 122, respectively; positioning and connecting the first rigid structural member 121 and the second rigid structural member 122 to each other in a clamping manner; fixedly mounting the first and second rigid

structural members

121 and 122 on the support plate 123; the display chip 1130 is fixedly mounted on the first rigid structure 121.

In step S902, the projection lens 13 of the projection module 10 is disposed at a predetermined position of the projection module 10. It should be noted that, the preset position may achieve rough positioning of the projection module 10 relative to the first rigid structure 121, and the preset position does not consider, for example, the assembly tolerance generated in step S901, and when the projection lens 13 is placed at the preset position, the projection image generated by the projection module 10 is easily distorted, for example.

In step S903, the positioning of the projection lens 13 of the projection module 10 relative to the substantially assembled projection display device 11 is adjusted until the projection image output by the projection lens 13 of the projection module 10 meets the predetermined requirement.

It should be noted that the adjustment principle and the assembly system used in the step S903 may be similar to those of the display module 113 in the step S803 of the embodiment shown in fig. 8, except that the position movable element of the adjustment process is converted into the projection lens 13 by the display module 113.

In adjusting the positioning of the projection lens 13, the positioning adjustment of the projection lens 13 may include the following actions:

adjusting the inclination angle of the projection lens 13 relative to the first rigid structural member 121 until the imaging definition of the projection image output by the projection lens 13 meets the corresponding preset requirement;

translating the projection lens 13 relative to the first rigid structure 121 in the xoy plane until the brightness uniformity of the projected image meets the corresponding predetermined requirement; and

the projection lens 13 is translated in the z-direction relative to the first rigid structure 121 until the virtual image distance of the projected image meets the respective predetermined requirements.

Accordingly, in the case where the projection image output by the projection lens 13 of the projection module 10 meets a predetermined requirement, the optical axis between the projection lens 13 and the display chip 1130 is determined to be substantially uniform; the projected image meeting the predetermined requirements includes: the imaging definition of the projection image meets corresponding preset requirements, the brightness uniformity of the projection image meets corresponding preset requirements, and the virtual image distance of the projection image meets corresponding preset requirements.

It will be appreciated that since light-converting element 1112 and display chip 1130 have been fixedly disposed in first rigid structure 121, the positioning of alignment projection lens 13 relative to first rigid structure 121 also indicates the positioning of alignment projection lens 13 relative to light-converting element 1112 and display chip 1130.

In step S904, the projection lens 13 is fixedly mounted with respect to the projection display device 11, which has been substantially assembled, in the aligned position. It will be appreciated that the adjusted positioning in step S903 may be determined or recorded, and the adjusted positioning may specifically indicate that, under the positioning condition, the imaging sharpness of the projection image meets the corresponding predetermined requirement, the brightness uniformity of the projection image meets the corresponding predetermined requirement, and the virtual image distance of the projection image meets the corresponding predetermined requirement. With this adjusted positioning, the gap between the projection lens 13 and the first rigid structure 121 is determined.

Specifically, the projection lens 13 is fixed relative to the first rigid structure 121 by a connecting medium such as a colloid, and the colloid is disposed in a gap between the projection lens 13 and the first rigid structure 121.

The assembly method of the above embodiment can obtain the projection module 10 of the embodiment shown in fig. 1 after the assembly is completed, and through the active adjustment of step S903, the assembly error generated in the assembly process of step S901 can be overcome, so that the optical axes among the display chip 1130, the light conversion element 1112 and the projection lens 13 are basically consistent, the consistency of the optical axes is improved, and the quality of the projection image is improved.

The applicant notes that the image quality projected by the projection module directly determines the image quality received by human eyes from the near-eye display device, and the waveguide sheet of the near-eye display device performs two-dimensional pupil expansion on the image and also has an angle requirement on received light, namely, the incident light of the waveguide sheet needs to be within an angle range, so that the light can be transmitted and expanded in the waveguide sheet; therefore, the light rays with different angles of each view field emitted by the projection module meet the corresponding angle requirements, and the relative position relationship (such as angle and distance) between the projection module and the waveguide sheet also has the corresponding precision requirements.

The following further illustrates a near-eye display device and an assembling method thereof according to an embodiment of the present invention. For ease of understanding and description, the X-direction, the Y-direction, and the Z-direction are defined based on the orientation of the near-eye display device, wherein the Y-direction is a substantially horizontal direction that is parallel to the direction in which both eyes of the human eye are located, the Z-direction corresponds to the height direction of the near-eye display device, the X-direction is substantially perpendicular to the YOZ plane, substantially parallel to the coupling-out direction of the waveguide sheet, and wherein the positive X-direction is opposite to the coupling-out direction of the waveguide sheet.

Referring to fig. 10-13, a near-eye display device 200 of an embodiment is shown. The near-eye display device 200 mainly includes a projection module 10, a waveguide 230, and a stand 210. The projection module 10 can use the projection module of any of the above embodiments, and the projected image has small distortion and good quality. The bracket 210 is used for carrying and installing the positioning projection module 10 and the waveguide sheet 230; the waveguide 230 and the projection module 10 are positioned and mounted on the bracket 210 such that the center of the light projected by the projection module 10 falls approximately at the center of the coupling-in region 232 of the waveguide 230.

As shown in fig. 10 and 11, in an embodiment, two projection modules 10 corresponding to the left and right sides of the binocular arrangement may be fixedly mounted on the bracket 210 along the X direction, such that each projection module 10 is positioned and mounted on the bracket 210 in a substantially vertical alignment with the coupling-in region 232 of the waveguide plate 230; specifically, during the assembly process between each projection module 10 and the bracket 210, the position may be determined by the limiting structure first, and then the relative positions of the two may be fixed by means of painting and exposing, so as to realize that each projection module 10 is fixedly mounted on the bracket 210, for example, on the supporting plate 213 of the fixed mounting bracket 210. It should be noted that the support plate 213 may replace the support plate 123 of the projection module 10 (see fig. 1), or may be integrally provided with the support plate 123 of the projection module 10.

As shown in fig. 13, the waveguide plate 230 has a coupling-in region 232, a coupling-out region 231, and a photoresist region 233 thereon; the coupling-in area 232 is used for receiving the light rays projected by the projection module 10, so that the light rays are transmitted in the waveguide plate and two-dimensional pupil expansion is performed, and finally, the image light rays are emitted in the coupling-out area 231 and observed by human eyes; the photoresist areas 233 reserved on the waveguide 230 are not subjected to grating engraving.

It will be appreciated that the specific location of the coupling-in region 232 on the waveguide 230 may be set according to the mounting orientation of the projection module 10 on the bracket 210, thereby facilitating entry of the projection image of the projection module 10 into the coupling-in region 232.

When the incident light is coupled into the coupling region 232, the angle between the light and the surface of the waveguide sheet 230 may affect the transmission efficiency of the waveguide sheet, and an improper coupling angle may also cause distortion of the finally observed image; therefore, the optimum image quality can be obtained by actively adjusting the waveguide 230 in real time. It should be noted that, since there is always an error in grating writing on the waveguide sheet 230, active tuning of the waveguide sheet 230 can also compensate for the effect of the error on the output image. In addition, by actively adjusting the position of the waveguide 230 relative to the projection module 10, the light center of the projection module 10 is exactly located at the center of the waveguide coupling region 232, so as to ensure the undistorted projected image and reduce the light energy loss.

With continued reference to fig. 10 and 11, the two projection modules 10 are located on the coupling-out side of the waveguide 230 (i.e. the side corresponding to the human eye), so that the projection modules 10 can project the projection image from the coupling-out side to the coupling-in region 232 of the waveguide 230. In other embodiments, the projection module 10 may also be located substantially opposite to the coupling-out side of the waveguide 230, such that the projection module 10 may project a projection image from the coupling-in area 232 of the waveguide 230 opposite to the coupling-out side.

In one embodiment, the support 210 is provided with receiving structures 220, for example, left and right receiving structures 220 respectively corresponding to two waveguide sheets 230; the receiving structure 220 at least partially receives the waveguide sheet 230; in the case that the positioning of the waveguide 230 with respect to the bracket 210 is well adjusted, the waveguide 230 may be positioned and mounted on the bracket 210 by the colloid 221 in the receiving structure 220, so that the center of the projected light of the projection module 10 falls approximately at the center of the coupling-in area 232 of the waveguide 230.

It should be noted that the glue 221 in the receiving structure 220 may be disposed on two sides corresponding to the glue drawing area 233 of the waveguide plate 230 (see fig. 12), and the glue 221 on each side is located between the waveguide plate 230 and the inner wall of the receiving structure 220; in yet another embodiment, the glue 221 may be disposed on one side with respect to the glue drawing area 233 of the waveguide 230 (see fig. 21), and the glue 221 disposed on one side is located between the waveguide 230 and the inner wall of the receiving structure 220. It will be appreciated that the double sided arrangement of the glue 221 (i.e. double sided tape) may effectively balance the effect of the deformation caused by the curing of the glue on the waveguide sheet 230.

In order to facilitate glue injection, a plurality of glue injection holes 211 are provided at positions of the support 210 corresponding to the receiving structure 220 and the glue drawing area 233 of the waveguide 230, and when glue is drawn, glue can be injected from the glue injection holes 211 into the receiving structure 220 and contacted with the glue drawing area 233, and then exposure and glue solidification are performed. In the case of arranging the glue 221 bilaterally, the front and rear glue injection holes 211b and 211a may be correspondingly provided on the main bracket 210b (which is located at the coupling-out side of the waveguide sheet 230) and the sub-bracket 210a (which is located at the opposite side of the coupling-out side of the waveguide sheet 230), respectively.

Alternatively, the inner wall of the receiving structure 220 is provided with protrusions (not shown in the drawings) protruding toward the waveguide sheet 230, and the shapes thereof may be, but are not limited to, saw-tooth, rectangular, triangular, etc.; the protrusions may serve to increase the surface area of the gel 221 in contact with the inner wall of the receiving structure 220, thereby improving the adhesive force.

Optionally, the inner wall of the receiving structure 220 is provided with a glue overflow groove 212 (see fig. 12), the glue overflow groove 212 may be used to accommodate the excessive glue, and the edge of the bracket may also have a glue overflow preventing structure; the glue overflow groove 212 may be specifically disposed at the corner of the inner wall of the receiving structure 220. The edge of the holder 210 may be further provided with a glue overflow preventing structure to prevent glue from overflowing before curing and contaminating the optical area of the waveguide 230.

Referring to fig. 12, the receiving structure 220 may be a cavity structure surrounded by the main bracket 210b and the sub-bracket 210a, and each of the waveguide sheets 230 is positioned to be installed in one of the receiving structures 220 between the main bracket 210b and the sub-bracket 210 a; the width of the receiving structure 220 in the x-direction is greater than the thickness of the waveguide sheet 230, for example, the width of the receiving structure 220 may be sized such that a single-sided gap 223 between the waveguide sheet 230 and an inner wall of the receiving structure 220 is in a range of 0.25mm or more and 1mm or less (e.g., 0.5mm, 0.8mm, etc.) when the waveguide sheet 230 is received and fixed; in this way, the positioning of the waveguide plate 230 in the receiving structure 220 can be aligned on-line before the waveguide plate 230 is fixed to the receiving structure 220, that is, the receiving structure 220 provides the redundant space required for alignment of the positioning of the waveguide plate 230 relative to the support 210.

Alternatively, the support 210 may be a split support in which the main support 210b and the sub support 210a are detachably and fixedly coupled together and form the receiving structure 220, and the main support 210b and the sub support 210a may be fixedly coupled together by screws, for example. In other embodiments, the primary and

secondary supports

210b, 210a may be bonded together by glue or the like and form the receiving structure 220. Of course, in other embodiments, the bracket 210 may be an integral bracket.

In the case where the projection module 10 is positioned and mounted on the support plate 213 and active adjustment of the display chip 1130 or the projection lens 13 is required (i.e., in the case of active adjustment on the main support 210 b), the sub-support 210a is not mounted on the main support 210b before the active adjustment of the display chip 1130 or the projection lens 13, considering the requirement of receiving the projection image of the projection module 10 by the receiving camera 91, so that the sub-support 210a is prevented from blocking the extending direction of the projection module 10 in which light is emitted, and active adjustment is facilitated by the receiving camera 91. After actively aligning the display chip 1130 or the projection lens 13 on the main support 210b, the sub-support 210a may be fixed to the main support 210b by screws or glue, etc.

In other embodiments, the sub-bracket 210a may be fixed relative to the main bracket 210b (not shown) in a positioning manner avoiding the coupling-in area 232 of the waveguide 230, so that the sub-bracket 210a does not substantially block the extending direction of the projection module 10 in which the light exits, and the projection module 10 is convenient to actively calibrate on the main bracket 210 b.

It should be noted that, the positioning of the waveguide 230 relative to the projection module 10 may be actively adjusted and determined before the curing of the adhesive 221. The positioning of the waveguide 230 relative to the projection module 10 will be described in the assembly method illustrated in fig. 23 below.

Fig. 14 to 18 show a near-eye display device 300 of a second embodiment of the present invention and a waveguide sheet 230 used therefor. The near-eye display device 300 of the second embodiment is different from the near-eye display device 200 of the first embodiment mainly in that the projection module 10 is positioned and mounted on the support 210 substantially parallel to the coupling-in region 232 of the waveguide sheet 230, a refractive prism 340 is disposed between the projection module 10 and the coupling-in region 232 of the waveguide sheet 230, and the refractive prism 340 is positioned and mounted with respect to the support 230 such that the center of the light beam projected by the projection module 10 falls on the center of the coupling-in region 232 of the waveguide sheet 230 after being refracted by the prism 340.

Specifically, referring to fig. 14 to 18, the projection modules 10 on the left and right sides are oppositely arranged along the Y-axis, the light projected by each projection module 10 is refracted by one refraction prism 340 and enters the coupling-in region 232 of the waveguide sheet 230, the projection module 10 and the bracket 210 can be pre-connected through the step bearing surface, the limiting hole 1232 and other limiting structures on the supporting plate 213, and then the glue is drawn and exposed in the glue drawing groove 1231, and the relative positions of the two are fixed (see fig. 17). The refractive prism 340 and the bracket 210 may be pre-coupled by a limiting structure such as a limiting column 341, and then glued and exposed in a glue slot 342, fixing the relative positions of the two (see fig. 17).

Fig. 19 to 21 show a near-eye display device 400 of a third embodiment of the present invention. The near-eye display device 400 of the third embodiment is mainly different from the near-eye display device 200 of the first embodiment in that the stand 210 does not include a stand located outside the waveguide 230, i.e., the sub-stand 210a as shown in fig. 11 is omitted; the receiving structure 220 may be a semi-open cavity structure formed by the integrated bracket 210; the glue 221 may be disposed on a single side with respect to the glue drawing area 233 of the waveguide 230 (see fig. 21), and the glue 221 disposed on a single side is located between the waveguide 230 and the inner wall of the receiving structure 220.

Fig. 22 is a schematic structural view of a near-eye display device according to a fourth embodiment of the present invention. The near-eye display device 500 of the fourth embodiment is different from the near-eye display device 200 of the first embodiment mainly in that the bracket 210 is provided with an avoiding opening 213 at a position corresponding to the coupling-in region 232 of the waveguide 230, and the avoiding opening 213 is used for avoiding the light beam projected by the projection module 10). Therefore, the sub-bracket 210a does not substantially block the extending direction of the projection module 10 in which the light is emitted, so that the projection module 10 can be actively adjusted on the bracket 210. The escape openings 213 may be provided at both left and right sides of the sub-mount 210 a.

The method of assembling the near-eye display device according to an embodiment of the present invention is illustrated below with reference to the near-eye display device 200 of the first embodiment and fig. 23.

Firstly, in step S2301, the projection module 10 is positioned and mounted on the bracket 210;

in step S2302, the positioning of the waveguide 230 relative to the bracket 210 is adjusted until the center of the light beam projected by the projection module 10 falls at the center of the coupling-in region 232 of the waveguide 230.

Specifically, the waveguide sheet 230 is first inserted into the receiving structure 220 of the bracket 210, and a gap exists between the waveguide sheet 230 and the bracket 210, and the gap can be used for fine tuning the waveguide sheet 230, and the single-side gap value is 0.25mm-1mm, for example, 0.55mm; if the gap is too small, the reserved adjustment space is insufficient, interference is generated between the waveguide 230 and the bracket 210, and if the gap is too large, the colloid is too much, which results in problems such as difficulty in solidifying the colloid and large shrinkage during solidifying the colloid, and the reliability is easily reduced.

Since the angle between the incident light and the surface of the waveguide sheet 230 may affect the transmission efficiency of the waveguide sheet 230 when the incident light is coupled, an improper coupling angle may also cause distortion of the finally observed image, so that the waveguide sheet 230 is further actively calibrated in real time to obtain a better image quality. It will be appreciated that since the grating of the waveguide plate 230 is prone to errors, active alignment of the waveguide plate 230 may also compensate for the effects of such errors on the output image. In addition, by actively calibrating the relative positions of the waveguide 230 and the projection module 10, the light center of the projection module is exactly located at the center of the waveguide coupling region 232, so as to ensure the undistorted projected image and reduce the light energy loss.

In the active calibration process, the projection module 10 projects a specific image and can be received by a receiving device (for example, the receiving camera 91) arranged on the eye side, the waveguide 230 can be actively adjusted in the directions of six degrees of freedom of the X axis, the Y axis, the Z axis, the XOY plane, the YOX plane and the XOZ plane in real time by means of an external positioning system, and the best installation position of the waveguide 230 can be determined by identifying the received image.

In an embodiment, the distance between the receiving device and the waveguide sheet 230 may simulate the distance between the human eye and the waveguide sheet 230, for example, 1cm-2cm, the projection module 10 may project a predetermined image, for example, a reticle image, and the receiving device may adjust the waveguide sheet on the XOZ plane and YOX plane by determining the position of the received reticle, specifically, a standard reticle pattern may be set on a camera lens of the receiving device, and the direction and/or the size of the waveguide sheet 230 that needs to be adjusted may be determined by determining the positional relationship between the reticle projected by the projection module 10 received by the receiving device and the standard reticle pattern; and the brightness test of the image is used for adjusting the positions of the X axis, the Y axis and the X axis of the waveguide sheet, so that the uniformity of brightness is ensured. It will be appreciated that the cross pattern used in the present method is only one exemplary pattern, e.g., the cross pattern may be replaced with other patterns such as a lattice; besides the automatic active calibration by using software, the more visual cross pattern is convenient to calibrate manually, and the active calibration can be performed manually when the adjustment range exceeds the upper limit set by the software, so that the reject ratio of products is reduced.

Alternatively, the bracket 210 may be provided with marking points for positioning and mounting the waveguide sheet 230 directly with respect to the bracket 210 by machine vision techniques; for example, in the active calibration process, the position of the waveguide sheet 230 may be adjusted on the YOZ plane by identifying the mark point, and further, the relative positions of the waveguide sheet 230 and the projection module 10 may be aligned by directly using the identification of the mark point.

It should be noted that the active alignment process of the waveguide sheet 230 in the above example may be repeated for each waveguide sheet 230, although the waveguide sheet 230 may obtain different positioning results.

In step S2303, the waveguide 230 is fixed to the support 210 in the adjusted position.

Under the well-regulated positioning, the position of the waveguide sheet 230 is determined, glue is injected into the glue-drawing areas 233 of the waveguide sheet 230 through the glue-injecting holes 211 on the two sides of the bracket 210, and the glue 211 is exposed and solidified through the glue-injecting holes 211, so that the waveguide sheet 230 is fixed relative to the bracket 210.

The above-mentioned assembly method can adjust the relative positions of the waveguide sheet 230 and the projection module 10 in the five degrees of freedom directions by adopting an active calibration mode, and can accurately determine the relative positions of the waveguide sheet 230 and the projection module 10 by identifying the image, which is received by the receiving device and is output by the projection module 10 and is acted by the waveguide sheet 230, in real time; in addition, the device can be fixed in a gluing exposure mode, the adopted mechanical structural parts are few, the assembly tolerance of the near-to-eye display device is low, and the assembly process is simpler. As a result, the assembly method of the above example obtains a near-eye display device and can provide an image of high imaging quality.

Although the invention has been described in connection with one or more implementations, alterations and/or modifications may be made to the described examples without departing from the spirit or scope of the appended claims. Furthermore, while a particular feature of the invention may have been disclosed with respect to only one of several implementations/embodiments, such feature may be combined with one or more other features of the other implementations/embodiments as may be desired and advantageous for any given or particular function.

Claims

The utility model provides a projection module (10), its includes projection display device (11) and projection lens (13), projection display device (11) include illumination component (111) and have display module (113) of display chip (1130), a serial communication port still includes rigid structure (121), the light conversion component (1112) of illumination component (111) fixed mounting in rigid structure (121), display module (113) with have the clearance between rigid structure (121).
Projection module (10) according to claim 1, characterized in that a connecting medium is provided in the gap, which connecting medium secures the display module (113) to the rigid structure (121).
The projection module (10) according to claim 1 or 2, wherein a first window (124) is formed on one side of the rigid structural member (121), the display module (113) is fixed at a window position corresponding to the first window (124), and the display module (113) and the light conversion element (1112) are respectively located at two sides of the first window (124).
A projection module (10) according to any of claims 1 to 3, wherein the gap is in the range of 0.05mm or more and 1mm or less, or further in the range of 0.1mm or more and 0.6mm or less.
The projection module (10) of any of claims 1 to 4, wherein the gap is configured to: the positioning of the display chip (1130) relative to the illumination assembly (111) is determined such that the image projection image output by the projection lens (13) meets a predetermined requirement in the determined positioning.
The projection module of claim 5, wherein the projected image meeting predetermined requirements comprises: the imaging definition of the projection image accords with corresponding preset requirements, the brightness uniformity of the projection image accords with corresponding preset requirements, and the virtual image of the projection image accords with corresponding preset requirements; or further comprising: the projected image is capable of entering the human eye in a substantially horizontal or substantially vertical orientation.
The projection module (10) according to any one of claims 2 to 6, wherein the display module (113) is fixed to the rigid structure (121) by means of a cured connecting medium in the gap, such that the display chip (1130) is fixed in the projection module (10) based on the determined positioning.
The projection module (10) of any of claims 1 to 7, wherein the illumination assembly (111) comprises a light source module (1110);

the light conversion element (1112) is configured to at least partially convert light emitted by the light source module (1110) to the display chip (1130), and/or at least partially convert light returned by the display chip (1130) to the projection lens (13) of the projection module (10).
The projection module (10) according to any one of claims 3 to 8, wherein the first fenestration (124) is configured to enable the display module (113) to be positioned and mounted at the fenestration corresponding to the first fenestration (124) from outside the rigid structure (121).
The projection module (10) of any of claims 3 to 9, wherein the display module (113) comprises a substrate (1131) for attaching the display chip (1130);

wherein a connection medium for fixing the display module (113) on the rigid structural member (121) is arranged between the edge part of the substrate (1131) and the step (1212) corresponding to the first window (124) and used for supporting and positioning the substrate (1131).
The projection module (10) of any of claims 2 to 10, wherein the connection medium is configured to seal the gap.
Projection module according to any of claims 2 to 11, wherein the connection medium has a thickness arrangement of non-uniform thickness such that the display module (113) is positioned obliquely with respect to the rigid structure (121).
The projection module (10) of any of claims 1 to 12, wherein the projection module (10) further comprises a support plate (123);

wherein, be provided with drawing gluey groove (1231) and limit structure (1232) on backing plate (123), be provided with in drawing gluey groove (1231) and be used for fixed mounting rigid structure (121)'s linking medium, limit structure (1232) correspond rigid structure (121) set up and be used for with rigid structure (121) spacing install in on backing plate (123).
The projection module (10) according to any one of claims 3 to 13, characterized in that a second opening (126) towards the light source module (1110) and a third opening (127) towards the projection lens (13) are also provided on the outer wall of the rigid structure (121);

wherein the projection lens (13) is positioned and mounted on the third opening window (127) so that the projection lens (13) is positioned and mounted relative to the projection display device (11).
The projection module (10) according to claim 14, characterized in that the projection lens (13) is positioned on the third fenestration (127) by a connecting medium of a desired thickness arrangement and/or shape with the positioning of the projection lens (13) relative to the rigid structure (121) adjusted.
A near-eye display device (200), comprising: a waveguide (230), a projection module (10) according to any one of claims 1 to 15, and a bracket (210);

wherein the waveguide sheet (230) and the projection module (10) are positioned and mounted on the bracket (210) such that the center of light projected by the projection module (10) falls at the center of the coupling-in region (232) of the waveguide sheet (230).
The assembling method of the projection module is characterized by comprising the following steps:

assembling an illumination assembly (111) of the projection module (10), wherein a light conversion element (1112) of the illumination assembly (111) is fixedly mounted to a rigid structural member (121);

setting a display module (113) with a display chip (1130) at a preset position of the projection module (10) so as to leave an initial gap between the display module (113) and the rigid structural member (121);

Based on the preset position, adjusting the positioning of the display module (113) relative to the lighting assembly (111) until the projection image output by the projection lens (13) of the projection module (10) meets the preset requirement, and correspondingly, the initial gap is adjusted and determined to be the adjusted gap; and

-fixing the display module (113) with respect to the illumination assembly (111) in the calibrated position.
The assembly method of claim 17, wherein in the calibrating step, a positioning of the display chip (1130) with respect to the assembled lighting assembly (111) is actively calibrated or a positioning of the display chip (1130) with respect to the assembled lighting assembly (111) is adjusted using machine vision techniques.
The method of assembling of claim 17 or 18, wherein the projected image meeting predetermined requirements comprises: the imaging definition of the projection image accords with corresponding preset requirements, the brightness uniformity of the projection image accords with corresponding preset requirements, and the virtual image distance of the projection image accords with corresponding preset requirements; or further comprising: the projected image is capable of entering the human eye in a substantially horizontal or substantially vertical orientation.
The assembly method according to any one of claims 17 to 19, wherein the preset position is located outside the rigid structure (121);

in the adjustment step, the positioning of the display module (113) with the display chip (1130) relative to the rigid structure (121) is adjusted from the outside of the rigid structure (121), thereby adjusting the positioning of the display chip (1130) relative to the illumination assembly (111).
The assembly method of any one of claims 17 to 20, wherein the tuning comprises one or more of:

adjusting the inclination angle of the display module (113) relative to the rigid structural member (121) until the imaging definition of the projection image output by the projection lens (13) of the projection module (10) meets the corresponding preset requirement;

translating the display module (113) relative to the rigid structure (121) in an xoy plane, which is based on a direction perpendicular to light rays emitted from the light converting element (1112) of the illumination assembly (111) towards the display chip (1130), until a brightness uniformity of the projected image meets respective predetermined requirements;

translating the display module (113) relative to the rigid structure (121) along a z-direction, which is a direction of light rays emitted from the light conversion element (1112) of the illumination assembly (111) to the display chip (1130), until a virtual image distance of the projected image meets corresponding predetermined requirements;

The display module (113) is rotated relative to the rigid structure (121) in the xoy plane until the projected image is able to enter the human eye in a substantially horizontal or substantially vertical orientation.
The assembling method according to any one of claims 17 to 21, wherein in the fixing step, the substrate (1131) to which the display chip (1130) is attached is fixed with respect to the rigid structural member (121) of the illumination assembly (111) to which the light conversion element (1112) is fixedly mounted through a connection medium.
The assembly method according to any one of claims 17 to 22, wherein in the step of adjusting, by adjusting the positioning of the display chip (1130) with respect to the assembled lighting assembly (111), an initial gap between the display module (113) and the rigid structure (121) is determined to obtain the adjusted gap; wherein the connecting medium is arranged in the gap after adjustment.