Projection light machine and wearable device

Abstract

The embodiment of the invention discloses a projection light machine and wearable equipment. The projection light machine comprises a light source module, a light guide device, a light splitting device and a projection system. The light source module is used for emitting illumination light; the light guide device comprises a substrate, a coupling-in area and a coupling-out area, wherein the coupling-in area and the coupling-out area are arranged on the substrate. The light source module is located on the side, provided with the coupling-in area, of the substrate. The light splitting device is embedded in the substrate; the projection system is located on the side, away from the light source module, of the substrate. The illumination light enters the substrate through the coupling-in area and then is emitted into the projection system to form projection light, the projection light is reflected into the substrate, and the light splitting device is at least located on a propagation path of the projection light. The reflection area is used for reflecting the projection light rays and enabling the projection light rays to be totally reflected and propagated to the coupling-out area in the substrate, and the coupling-out area is used for coupling out the projection light rays.

Description

Technical Field

[0001] The present application belongs to the field of optical projection technology. Specifically, the present application relates to a projection optical machine and a wearable device. Background Art

[0002] AR technology is a technology that integrates images into reality through optical methods to achieve augmented reality. Taking AR glasses as an example, it is one of the important forms of AR technology. Among them, the display is projected to the left and right eyes of the wearer through two optical machines respectively. The fusion distance of the binocular images can be adjusted through the image algorithm to give the human eye a sense of distance.

[0003] However, the current projection optical engine solution has the problem of being too large in size. For example, the volume of a DLP optical engine is 5 to 6 cc, and the volume of a traditional LCOS optical engine is 3 to 4 cc, which is not conducive to the lightweight of AR glasses. Specifically, the traditional projection optical engine solution is mainly divided into the light source part (or lighting part) and the projection imaging part. The light source part often uses multiple lamps and multi-channel light sources, and finally uses a light-combining prism to unify the light source, which often increases the volume and makes the entire projection optical engine too bulky. Summary of the invention

[0004] The purpose of this application is to provide a new technical solution for a projection light machine and a wearable device, which is a compact light machine optical architecture that at least solves the problem of the large size of existing projection light machines.

[0005] According to a first aspect of the present application, a projection optical engine is provided. The projection optical engine comprises:

[0006] A light source module, used for emitting illumination light;

[0007] A light guide device, the light guide device comprising a substrate and an incoupling region and an outcoupling region arranged on the substrate, the light source module being located on a side of the substrate where the incoupling region is arranged;

[0008] A light splitting device, wherein the light splitting device is obliquely embedded in the substrate;

[0009] A projection system, the projection system is located on a side of the substrate away from the light source module, and at least a portion of the projection system is opposite to the coupling-in area;

[0010] The illumination light enters the substrate through the coupling-in area and then emerges into the projection system to form projection light. The projection light is reflected back into the substrate, and the spectroscopic device is at least located on the propagation path of the projection light, for reflecting the projection light and making the projection light totally reflected in the substrate and propagated to the coupling-out area, and the coupling-out area is used to couple out the projection light.

[0011] Optionally, the light source module and the light splitting device are arranged opposite to each other in a thickness direction of the substrate, and the thickness direction is a direction perpendicular to two opposite surfaces of the substrate;

[0012] The light source module covers the coupling-in area on one side of the substrate, and the illumination light coupled into the substrate through the coupling-in area can be transmitted through the light splitting device and then emitted into the projection system.

[0013] Optionally, the light source module and the spectroscopic device are staggered in the thickness direction of the substrate, and the thickness direction is perpendicular to the two opposite surfaces of the substrate. The illumination light coupled into the substrate through the coupling region is directly emitted into the projection system.

[0014] Optionally, the light source module and the light splitting device each occupy half of the coupling-in area.

[0015] Optionally, the optical splitter is provided as one or more.

[0016] Optionally, the beam splitter is a semi-reflective and semi-mirror device, and a polarizing reflective film is provided on any surface of the beam splitter.

[0017] Optionally, the light source module includes an illumination light source and a light homogenizing device, and the light homogenizing device is arranged on a light output path of the illumination light source; or, the light source module is an LED point array light source.

[0018] Optionally, the light source module can emit illumination light of multiple different wavelength bands, and the illumination light can directly enter the light guide device and then be transmitted to the projection system to form the projection light.

[0019] Optionally, the projection system comprises an eyepiece and an image source arranged in sequence;

[0020] The eyepiece includes a plurality of lenses arranged along the same optical axis;

[0021] The image source includes an LCOS chip or a DLP chip.

[0022] Optionally, the illumination light entering the projection system passes through the eyepiece and is projected to the image source to form the projection light. The projection light is reflected from the image source to the eyepiece and enters the substrate after being transmitted through the eyepiece.

[0023] Optionally, the light guiding device is an optical waveguide element.

[0024] According to a second aspect of the present application, a wearable device is also provided. The wearable device comprises:

[0025] a housing; and

[0026] A projection optical machine as described in the first aspect.

[0027] The beneficial effects of this application are:

[0028] The projection optical machine proposed in the embodiment of the present application introduces a light-guiding device to transmit light between the light source module and the projection system, wherein the light source module and the projection system are arranged on both sides of the light-guiding device through the optimized design of the layout positions of the light source module, the light-splitting device and the projection system, and the light-splitting device is embedded in the base of the light-guiding device, so that the light source module and the projection system can share the light path, and the light-combining device is omitted in the entire optical architecture, thereby compressing the volume and realizing a compact design of the optical structure of the entire projection optical machine, thereby solving the problem of the existing projection optical machine being too bulky due to its large volume.

[0029] Other features and advantages of the present application will become apparent from the following detailed description of exemplary embodiments of the present application with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the application and, together with the description, serve to explain the principles of the application.

[0031] Figure 1 A schematic diagram of the structure of a projection optical machine provided in one embodiment of the present application;

[0032] Figure 2 A schematic diagram of the structure of a projection optical machine provided in another embodiment of the present application;

[0033] Figure 3 A schematic diagram of the structure of a projection optical machine provided in yet another embodiment of the present application.

[0034] Description of reference numerals:

[0035] 1. Light source module; 2. Light guide device; 21. Base; 22. Incoupling area; 23. Outcoupling area; 3. Beam splitter; 4. Projection system; 41. Eyepiece; 42. Image source; 01. Illumination light; 02. Projection light; 001. Human eye. DETAILED DESCRIPTION

[0036] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present application.

[0037] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present application, its application, or uses.

[0038] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0039] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0040] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0041] The projection light machine and the wearable device provided in the embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0042] According to one aspect of the present application, a projection optical machine is provided, which can be applied to, for example, an AR device. The AR device is, for example, an AR head-mounted display device, such as AR glasses or an AR helmet.

[0043] The projection optical machine provided in the embodiment of the present application is shown in FIG. Figures 1 to 3 The projection optical machine includes: a light source module 1, a light guide device 2, a light splitter device 3 and a projection system 4. The light source module 1 is used to emit an illumination light 01. The light guide device 2 includes a substrate 21 and a coupling-in area 22 and a coupling-out area 23 arranged on the substrate 21. The light source module 1 is located on a side of the substrate 21 where the coupling-in area 22 is arranged. The light splitter device 3 is obliquely embedded in the substrate 21. The projection system 4 is located on a side of the substrate 21 away from the light source module 1, and at least a part of the projection system 4 is opposite to the coupling-in area 22. The illumination light 01 enters the substrate 21 through the coupling-in area 22 and then emerges into the projection system 4 to form a projection light 02. The projection light 02 is reflected into the substrate 21, and the spectroscopic device 3 is at least located on the propagation path of the projection light 02, which can be used to reflect the projection light 02 and make the projection light 02 totally reflected in the substrate 21 and propagated to the coupling-out area 23, and the coupling-out area 23 is used to couple out the projection light 02.

[0044] According to the projection optical machine provided in the above embodiment, see Figures 1 to 3, wherein the light source module 1 is the lighting part of the projection light machine, which can emit an illumination light 01 for imaging display. The light guide device 2 can be used to transmit the illumination light 01 emitted by the light source module 1 to the projection system 4. The projection system 4 can make the incident illumination light 01 form a projection light 02 with image information. When the projection light 02 enters the substrate 21 of the light guide device 2 again, it can be reflected by the spectroscopic device 3 embedded in the substrate 21 to change the propagation direction of the light. At this time, the spectroscopic device 3 is used as a reflector, and the projection light 02 can be fully reflected in the substrate 21 and propagated to the decoupling area 23, and finally coupled out through the decoupling area 23, thereby forming a projection picture. In this way, the user can watch the projection picture from one side of the decoupling area 23 of the light guide device 2.

[0045] The light guide device 2 is located between the light source module 1 and the projection system 4, and the light guide device 2 can be used to realize the transmission of light between the two. In the projection optical machine provided in the embodiment of the present application, the light source module 1 and the projection system 4 are arranged on two opposite sides of the base 21. This design makes the optical architecture of the entire projection optical machine more reasonably arranged.

[0046] For traditional projection optical machine solutions, the lighting part often uses multiple lamp beads to form a multi-channel light source. On the path of light transmission, it is necessary to set up a light combining device such as a light combining prism to unify the light source, which is also called light combining processing. On this basis, the volume of the projection optical machine will be increased, making the entire projection optical machine relatively bulky, which will reduce the wearing comfort when applied to AR devices.

[0047] The projection optical machine provided in the embodiment of the present application adopts a light guide device 2 to transmit light between the light source module 1 and the projection system 4, which can save the need for a light combining device on the optical path. Light combining devices are large in size and occupy a large space. In the present application, the volume of the projection optical machine can be compressed by eliminating the traditional light combining device, and the miniaturization and light weight of the projection optical machine can be achieved.

[0048] The projection light machine according to the above-mentioned embodiment of the present application can be applied to, for example, the optical display part of AR glasses. Since the optical structure of the projection light machine is relatively compact, its volume is relatively small, which is conducive to the miniaturization design of AR glasses and can reduce the weight of the whole machine, thereby improving the wearing comfort of users.

[0049] The projection light machine provided in the embodiment of the present application is a compact optical structure design, in which the illumination light 01 emitted by the light source module 1 is transmitted by introducing a light guide device 2, and the illumination light 01 may include light of multiple different wavelength bands. The illumination light 01 includes, for example, red light, green light, or blue light. The illumination light 01 may be coupled into the substrate 21 through the coupling-in area 22 on the substrate 21, and then emitted to the projection system 4 opposite to the coupling-in area 22, and the illumination light 01 becomes a projection light 02 with image information. The projection light 02 may be reflected by the optical splitter 3 embedded in the substrate 21, and then propagate in the substrate 21 in a state of total reflection, and finally propagate to the coupling-out area 23 and then couple out to the outside of the substrate 21 for projection imaging.

[0050] In the projection light machine provided in the above embodiment of the present application, the light guide device 2 can play the role of transmitting the illumination light 01 emitted by the light source module 1 to the projection system 4, and the projection light 02 formed at the same time can also be coupled out for projection imaging after being transmitted through the light guide device 2. The introduction of the light guide device 2 can not only save the need to set up a light combining device, but also allow the light source module 1 and the projection system 4 to share the light path. The light guide device 2 has a thin and light appearance and a small size. After being applied to the projection light machine, it does not occupy a large space, which is conducive to reducing the volume and weight of the projection light machine.

[0051] The projection optical machine proposed in the embodiment of the present application introduces the light guiding device 2 to transmit light between the light source module 1 and the projection system 4, wherein the layout positions of the light source module 1, the light splitting device 3 and the projection system 4 are optimized. For example, the light source module 1 and the projection system 4 are designed to be arranged on both sides of the light guiding device 2, and the light splitting device 3 is embedded in the base 21 of the light guiding device 2. This allows the light source module 1 and the projection system 4 to share the light path, and the light combining device is omitted in the entire optical architecture, thereby compressing the volume and realizing a compact design of the optical structure of the entire projection optical machine, thereby solving the problem of the existing projection optical machine being too bulky due to its large volume.

[0052] In some examples of this application, see Figure 1 and Figure 2 The light source module 1 and the spectrometer 3 are arranged opposite to each other in the thickness direction of the substrate 21, and the thickness direction is a direction perpendicular to the two opposite surfaces of the substrate 21; the light source module 1 covers the coupling area 22, so that the illumination light 01 coupled into the substrate 21 through the coupling area 22 can be transmitted through the spectrometer 3 and then emitted into the projection system 4.

[0053] It should be noted that the substrate 21 of the light guide device is, for example, a thin sheet with a certain thickness. The substrate 21 has two opposite surfaces, and the thickness direction of the substrate 21 is a direction perpendicular to the two opposite surfaces.

[0054] Based on the above example, see Figure 1 and Figure 2 The coupling area 22 on the substrate 21 is relative to the projection system 4 in position, the light source module 1 is located on one side of the coupling area 22, and the light source module 1 is designed to occupy the entire coupling area 22, that is, the projection of the light source module 1 on the substrate 21 can cover the entire coupling area 22. At this time, the illumination light 01 emitted by the light source module 1 can cover the entire coupling area 22.

[0055] According to the above example, the light splitter 3 is tiltedly embedded in the substrate 21 and is opposite to the coupling-in area 22 in position, and it also occupies the entire coupling-in area 22. In this way, the illumination light 01 emitted by the light source module 1 passes through the light splitter 3 after entering the substrate 21 through the coupling-in area 22. At this time, the light splitter 3 plays the role of transmitting light, so that the propagation path of the illumination light 01 emitted by the light source module 1 passes through the light splitter 3 and then emerges into the projection system 4.

[0056] After the illumination light 01 passes through the projection system 4, a projection light 02 with image information can be formed. The projection light 02 is reflected into the substrate 21 and also encounters the spectrometer 3. At this time, the spectrometer 3 acts as a reflector to change the propagation direction of the light. The projection light 02 coupled into the substrate 21 will be totally reflected and propagated to the decoupling area 23, and finally coupled out by the decoupling area 23 to form a projection image.

[0057] The light splitting device 3 is, for example, a semi-reflective and semi-mirror device, which can transmit a part of the light and reflect another part of the light.

[0058] The light splitting device 3 may be embedded in the substrate 21 at an angle.

[0059] Optionally, the optical splitter 3 can be configured as one, see Figure 1 In this case, the size of the light splitter 3 is relatively large. When one light splitter 3 is embedded in the substrate 21, the light splitter 3 can be tilted at, for example, 30 degrees.

[0060] Optionally, the optical splitter 3 may be provided in a plurality of configurations, see Figure 2For example, the number of the optical splitter 3 can be two or three. In this case, the size of each optical splitter 3 is relatively small. The advantage of this design is that a larger optical splitter can be split into multiple small-sized optical splitters, and the inclination angle of each small-sized optical splitter can be set relatively small, which can reduce the thickness of the substrate 21. For example, the thickness of the substrate 21 can be reduced to about 0.8 mm. Figure 1 In the optical scheme of setting a spectrometer 3 shown in FIG. 1 , the thickness of the substrate 21 is about 2 mm.

[0061] In some examples of this application, see Figure 3 As shown, the light source module 1 and the spectrometer 3 are staggered in the thickness direction of the substrate 21, and the thickness direction is perpendicular to the two opposite surfaces of the substrate 21. The illumination light 01 coupled into the substrate 21 through the coupling area 22 is directly emitted into the projection system 4.

[0062] The light source module 1 and the light splitting device 3 each occupy half of the coupling-in area 22 .

[0063] Based on the above example, see Figure 3 The sizes of the light source module 1 and the spectrometer 3 are designed to be relatively small. Specifically, the two occupy half the size of the coupling-in area 22 respectively; and the light source module 1 and the spectrometer 3 are respectively arranged in a staggered manner on both sides of the coupling-in area 22. In this way, when the illumination light 01 emitted by the light source module 1 is emitted to the projection system 4 through the light guide device 2, the illumination light 01 does not pass through the spectrometer 3, which can improve the utilization rate of light energy. When the projection light 02 emitted by the projection system 4 propagates into the substrate 21, it will be reflected by the spectrometer 3 to change the light propagation path, so that the projection light 02 can be propagated to the coupling-out area 23 along the total reflection in the substrate 21.

[0064] See also Figure 3 The design of the above example can meet the basic projection imaging brightness and clarity requirements of the projection optical machine. Moreover, the size of the light source module 1 and the light splitting device 3 are relatively small, which can further reduce the volume and weight of the entire projection optical machine and reduce the production cost.

[0065] In some examples of this application, see Figures 1 to 3 The optical splitter 3 is configured as one or more optical splitters.

[0066] The spectrometer 3 is arranged in the base 21 of the light guide device 2. If there are multiple spectrometers 3, the inclination angle of each spectrometer 3 can be set to be relatively small, which is conducive to reducing the thickness of the base 21. The thickness of the base 21 is, for example, about 8 mm.

[0067] In some examples of the present application, the beam splitter 3 is a semi-reflective and semi-mirror device, and a polarized reflective film is provided on any surface of the beam splitter 3 .

[0068] According to the above example, the light splitting device 3 has polarization characteristics.

[0069] The use of a semi-reflective and semi-mirror beam splitter 3 is beneficial for reducing the thickness of the substrate 21 without increasing the size and weight of the entire projection optical machine.

[0070] In some examples of the present application, the light source module 1 includes an illumination light source and a light homogenizing device, and the light homogenizing device is arranged on the light output path of the illumination light source; or, the light source module 1 is an LED point array light source.

[0071] The illumination light source may include lamps of different colors, which can emit light of different colors such as red light, green light and blue light. Of course, the illumination light source may also include lamp beads of other colors, as long as they can emit visible light.

[0072] It should be noted that the light source module 1 may include a light homogenizing device, and the light source module 1 may also directly use a mini-LED dot matrix light source, and the illumination light 01 emitted is relatively uniform. , and there is no need to introduce a light homogenizing device.

[0073] In some examples of the present application, the light source module 1 can emit illumination light 01 of multiple different wavelength bands, and the illumination light 01 can directly enter the light guide device 2 and then be transmitted to the projection system 4 to form the projection light 02 .

[0074] The projection light machine provided in the embodiment of the present application does not need to be provided with a light combining device on the light output path of the light source module 1. The illumination light beams 01 of various different wavelength bands emitted by the light source module 1 can be directly projected into the light guiding device 2, which transmits the light beams. Compared with the traditional light combining device, the light guiding device 2 is thin and light in appearance and compact in size. When applied to the projection light machine, the light guiding device 2 does not occupy a large space, which is beneficial to reducing the size and weight of the projection light machine.

[0075] In some examples of this application, see Figures 1 to 3The projection system 4 includes an eyepiece 41 and an image source 42 which are arranged in sequence; the eyepiece 41 includes a plurality of lenses which are arranged along the same optical axis; and the image source 42 includes an LCOS chip or a DLP chip.

[0076] Among them, the illumination light 01 entering the projection system 4 is projected to the image source 42 after passing through the eyepiece 41, and the projection light 02 is formed at this time. The projection light 02 is reflected to the eyepiece 41 by the image source 42, and enters the substrate 21 after being transmitted through the eyepiece 41.

[0077] According to the above example, the projection system 4 includes, for example, the eyepiece 41 and the image source 42 mentioned above.

[0078] according to Figure 1 and Figure 2 In the optical architecture shown, the light source module 1 and the light splitting device 3 both occupy the entire field of view of the eyepiece 41. Figure 3 In the optical architecture shown, half of the field of view of the eyepiece 41 is used for the light source module 1 , and the other half of the field of view is used for the spectroscopic device 3 .

[0079] According to the above example of the present application, the eyepiece 41 and the image source 42 are located on the same side of the light guide device 2, so that the layout is simple.

[0080] The projection optical machine provided in the embodiment of the present application introduces a light guiding device 2 to realize the light input, light transmission and light coupling out of the illumination part of the projection optical machine, which can reduce the difficulty of the production process and the production cost of the projection optical machine. In addition, it eliminates the light combining device of the traditional solution, optimizes the volume size, and reduces the weight of the projection optical machine.

[0081] In some examples of the present application, the light guiding device 2 is an optical waveguide element.

[0082] The substrate 21 is a waveguide substrate, and the entire projection optical machine transmits light based on a diffraction optical waveguide.

[0083] The projection optical machine provided by the present application is further described below through Examples 1 to 3.

[0084] Example 1

[0085] See also Figure 1The optical projection machine includes a light source module 1, a light guide device 2, a light splitter 3 and a projection system. The light source module 1 can emit light of different wavelength bands. The light guide device 2 includes a substrate 21 and a coupling-in area 22 and a coupling-out area 23 arranged on the substrate 21. The light source module 1 is located on the side of the substrate 21 where the coupling-in area 22 is provided. At least part of the projection system 4 is opposite to the coupling-in area 22. The light splitter 3 is a half-reflecting half-mirror, and a polarizing reflection film is provided on any surface of the half-reflecting half-mirror. The half-reflecting half-mirror is set as one and embedded in the substrate 21. The projection system 4 is located on the side of the substrate 21 away from the light source module 1. The projection system 4 includes an eyepiece 41 and an image source 42 arranged in sequence; the eyepiece 41 includes a plurality of lenses arranged along the same optical axis, and the image source is an LCOS chip.

[0086] The light source module 1 and the spectroscopic device 3 are arranged correspondingly in the thickness direction of the substrate 21, and the light source module 1 covers the coupling-in area 22. The illumination light 01 enters the substrate 21 through the coupling-in area 22, and the illumination light 01 can be transmitted through the spectroscopic device 3 and then emitted into the projection system 4, and the illumination light 01 forms a projection light 02, and the projection light 02 is reflected into the substrate 21. At this time, the spectroscopic device 3 is also used to reflect the projection light 02 and make the projection light 02 fully reflected in the substrate 21 and propagated to the coupling-out area 23, and the coupling-out area 23 is used to couple out the projection light 02.

[0087] Example 2

[0088] See also Figure 2 The difference between this embodiment and the above-mentioned embodiment 1 is that the layout of the light splitting devices 3 arranged in the substrate 21 is different. In this embodiment, a plurality of light splitting devices 3 of smaller size are embedded in the substrate 21 .

[0089] Compared with Embodiment 1, the solution of this embodiment can reduce the thickness of the substrate 21 .

[0090] Example 3

[0091] See also Figure 3 The difference between the optical structure of the projection light machine provided in this embodiment and that in embodiment 1 is that the spectroscopic device 3 and the light source module 1 respectively occupy half of the coupling-in area 22, and the light source module 1 and the spectroscopic device 3 are staggered with each other in the thickness direction of the substrate 21. This design enables the illumination light 01 coupled into the substrate 21 through the coupling-in area 22 to be directly emitted into the projection system 4, that is, the illumination light 01 is directly projected into the projection system 4 without passing through the spectroscopic device 3.

[0092] In another aspect, an embodiment of the present application further provides a wearable device, wherein the wearable device comprises a housing and the above-mentioned projection light engine.

[0093] The above-mentioned wearable device is, for example, AR smart glasses or AR smart helmet.

[0094] The specific implementation of the projection light machine and the wearable device of the embodiment of the present application can refer to the above-mentioned embodiment of the projection light machine, so it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here one by one.

[0095] Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are only for illustration, not for limiting the scope of the present application. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A projection optical machine, characterized in that: include: A light source module (1) for emitting illumination light (01); A light guide device (2), the light guide device (2) comprising a substrate (21) and an incoupling region (22) and an outcoupling region (23) arranged on the substrate (21), the light source module (1) being located on a side of the substrate (21) on which the incoupling region (22) is arranged; A light splitting device (3), wherein the light splitting device (3) is obliquely embedded in the substrate (21); a projection system (4), the projection system (4) being located on a side of the substrate (21) facing away from the light source module (1), and at least a portion of the projection system (4) being opposite to the coupling-in area (22); The illumination light (01) enters the substrate (21) through the coupling-in region (22) and then emerges into the projection system (4) to form a projection light (02). The projection light (02) is reflected back into the substrate (21), and the optical splitter (3) is at least located on the propagation path of the projection light (02) and is used to reflect the projection light (02) and make the projection light (02) propagate through total reflection in the substrate (21) to the coupling-out region (23). The coupling-out region (23) is used to couple out the projection light (02).

2. The projection optical machine according to claim 1, characterized in that: The light source module (1) and the light splitting device (3) are arranged opposite to each other in the thickness direction of the substrate (21), and the thickness direction is a direction perpendicular to two opposite surfaces of the substrate (21); The light source module (1) covers the coupling-in area (22) on one side of the substrate (21); the illumination light (01) coupled into the substrate (21) through the coupling-in area (22) can be transmitted through the light splitting device (3) and then emitted into the projection system (4).

3. The projection optical machine according to claim 1, characterized in that: The light source module (1) and the light splitting device (3) are arranged to be staggered with each other in the thickness direction of the substrate (21), and the thickness direction is a direction perpendicular to two opposite surfaces of the substrate (21). The illumination light (01) coupled into the substrate (21) through the coupling-in region (22) is directly emitted into the projection system (4).

4. The projection optical machine according to claim 3, characterized in that: The light source module (1) and the light splitting device (3) each occupy half of the coupling-in area (22).

5. The projection optical machine according to any one of claims 1 to 4, characterized in that: The light splitting device (3) is provided as one or more.

6. The projection optical machine according to claim 5, characterized in that: The light splitting device (3) is a semi-reflective and semi-mirror device, and a polarized reflective film is provided on any surface of the light splitting device (3).

7. The projection optical machine according to claim 5, characterized in that: The light source module (1) comprises an illumination light source and a light homogenizing device, wherein the light homogenizing device is arranged on a light output path of the illumination light source; or the light source module (1) is an LED point array light source.

8. The projection optical machine according to claim 7, characterized in that: The light source module (1) is capable of emitting illumination light (01) of multiple different wavelength bands, and the illumination light (01) can directly enter the light guide device (2) and then be transmitted to the projection system (4) to form the projection light (02).

9. The projection optical machine according to claim 5, characterized in that: The projection system (4) comprises an eyepiece (41) and an image source (42) which are arranged in sequence; The eyepiece (41) comprises a plurality of lenses arranged along the same optical axis; The image source (42) includes an LCOS chip or a DLP chip.

10. The projection optical machine according to claim 9, characterized in that: The illumination light entering the projection system (4) is projected onto the image source (42) after passing through the eyepiece (41), thereby forming the projection light (02). The projection light (02) is reflected from the image source (42) to the eyepiece (41), and then enters the substrate (21) after being transmitted through the eyepiece (41).

11. The projection optical machine according to claim 1, characterized in that: The light guiding device (2) is an optical waveguide element.

12. A wearable device, characterized in that: include: case; as well as A projection light machine as claimed in any one of claims 1 to 11.

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