CN216748409U

CN216748409U - Optical projection module and electronic equipment

Info

Publication number: CN216748409U
Application number: CN202122993122.3U
Authority: CN
Inventors: 郭恒琳
Original assignee: Goertek Optical Technology Co Ltd
Current assignee: Goertek Optical Technology Co Ltd
Priority date: 2021-11-30
Filing date: 2021-11-30
Publication date: 2022-06-14
Anticipated expiration: 2031-11-30
Also published as: WO2023097767A1

Abstract

The application discloses optical projection module and illumination ray apparatus. The optical projection module includes: the light-adjusting lens comprises a display chip, a light-adjusting part, a first lens group and a second lens group, wherein the focal length of the first lens group is different from that of the second lens group; the display chip is provided with a first deflection angle and a second deflection angle, and can rotate and switch between the first deflection angle and the second deflection angle; the display chip rotates to a first deflection angle state to form a first light beam; the display chip rotates to a second deflection angle state to form a second light beam; the light adjusting component is used for receiving and modulating the first light beam and the second light beam so that the first light beam is incident to the first lens group and the second light beam is incident to the second lens group.

Description

Optical projection module and electronic equipment

Technical Field

The present application relates to the field of optical projection technology, and more particularly, to an optical projection module and an electronic device.

Background

At present, the projection optical system is developed rapidly and has wide application fields. However, the projector using the fixed focus lens can only project images within a certain distance, and cannot project images with different projection distances. The projector adopting the zoom lens can realize the transformation of the size and the distance of a projection picture by adjusting the focal length of the lens, but the zoom lens has the problems of limited zoom ratio, high design difficulty, high price cost, low yield and the like.

Therefore, the technical problem to be solved urgently is to enable the projector to display images with different projection distances and avoid the defects brought by the zoom lens.

SUMMERY OF THE UTILITY MODEL

An object of the present application is to provide a new technical solution for an optical projection module and an electronic device.

According to a first aspect of embodiments of the present application, an optical projection module is provided. The optical projection module includes: the light modulator comprises a display chip, a light adjusting component, a first lens group and a second lens group, wherein the focal length of the first lens group is different from that of the second lens group;

the display chip is provided with a first deflection angle and a second deflection angle, and can rotate and be switched between the first deflection angle and the second deflection angle;

the display chip rotates to the state of the first deflection angle to form a first light beam;

the display chip rotates to the state of the second deflection angle to form a second light beam;

the light adjusting component is used for receiving and modulating the first light beam and the second light beam so that the first light beam is incident to the first lens group and the second light beam is incident to the second lens group.

Optionally, the first lens group comprises a first fixed focus lens and a first multiplying mirror for receiving and transmitting a first light beam emitted from the first fixed focus lens;

the second lens group comprises a second fixed-focus lens and a second multiplying lens, the second multiplying lens is used for receiving and transmitting a second light beam emitted from the second fixed-focus lens, and the focal length of the first multiplying lens is different from that of the second multiplying lens.

Optionally, the optical projection module comprises a fixed focus lens, a first multiplying lens and a second multiplying lens, and the focal length of the first multiplying lens is different from that of the second multiplying lens;

the fixed-focus lens and the first multiplying lens form the first lens group;

the fixed-focus lens and the second zoom lens form the second lens group.

Optionally, the dimming component includes a first reflector disposed on the light exit side of the display chip and an optical component having diopter disposed on the light exit side of the first reflector.

Optionally, the dimming component is a turning prism.

Optionally, the turning prism has an incident surface, a reflecting surface and an exit surface, and at least one of the reflecting surface and the exit surface is a non-planar surface.

Optionally, the optical projection module further includes a first mirror group, and the first mirror group is located between the fixed-focus lens and the first magnification increasing mirror.

Optionally, the optical projection module further includes a second mirror group, and the second mirror group is located between the fixed-focus lens and the second magnification-increasing mirror.

According to a second aspect of embodiments of the present application, an electronic device is provided. The electronic equipment comprises the optical projection module of the first aspect.

One technical effect of the present application is that the optical projection module includes a display chip and a dimming part, a first lens group and a second lens group. Two non-overlapping light beams are formed by the display chip and the dimming component. Two non-overlapping light beams form two pictures with different projection ratios through the first lens group and the second lens group. The optical projection module can project pictures with different projection distances.

Further features of the present application and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which is to be read in connection with the accompanying drawings.

Drawings

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

Fig. 1 is a first schematic structural diagram of an optical projection module according to an embodiment of the present disclosure.

Fig. 2 is an enlarged view of a structure a in fig. 1.

Fig. 3 is a second schematic structural diagram of an optical projection module according to an embodiment of the present application.

Fig. 4 is a schematic structural diagram of an optical projection module according to an embodiment of the present application.

Fig. 5 is a schematic structural diagram of an optical projection module according to an embodiment of the present application.

Description of reference numerals:

1. a light emitting part; 2. a display chip; 21. a protective cover plate; 22. a micro-lens; 3. a dimming component; 4. a fixed focus lens; 51. a first magnification increasing mirror; 52. a second multiplying mirror; 61. a first reflector; 62. a second reflector; 63. a third reflector; 64. a fourth mirror; 65. a fifth reflecting mirror; 7. an optical element.

Detailed Description

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

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

Techniques and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be considered a part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be discussed further in subsequent figures.

In a first aspect of the embodiments of the present application, an optical projection module is provided. Referring to fig. 1-5, the optical projection module includes: the display device comprises a display chip 2, a dimming component 3, a first lens group and a second lens group, wherein the focal length of the first lens group is different from that of the second lens group;

the display chip 2 has a first deflection angle a1 and a second deflection angle a2, and the display chip 2 is capable of rotating and switching between the first deflection angle a1 and the second deflection angle a 2. For example, the display chip 2 receives incident light, and processes (e.g., reflects or transmits, etc.) the incident light to project the processed incident light to the dimming part 3.

The display chip 2 rotates to the first deflection angle a1 to form a first light beam L1. The display chip 2 rotates to the second deflection angle a2 to form a second light beam L2. The light adjusting part 3 is used for receiving and modulating the first light beam L1 and the second light beam L2, so that the first light beam L1 is incident to the first lens group, and the second light beam is incident to the second lens group.

In this embodiment, the optical projection module includes an illumination optical path and an imaging optical path. In this embodiment, the light beam emitted from the external light emitting part 1 is projected to the display chip 2. The display chip 2 and the dimming member 3 constitute an illumination light path. Two non-overlapping light beams are formed through the illumination light path. In a specific embodiment, the light emitted by the light emitting component 1 can penetrate through the dimming component 3 and then enter the display chip 2, and the light received by the display chip 2 after reflection can enter the dimming component 3 to form an illumination light path. The display chip 2 may be a digital micromirror device, for example.

The display chip 2 may be a reflective light modulator such as a Liquid Crystal On Silicon (LCoS) panel, a Digital Micro-mirror Device (DMD), and the like. In other embodiments, the display chip 2 may also be a transmissive light Modulator such as a Transparent Liquid Crystal Panel (transmissive Liquid Crystal Panel), an Electro-Optical Modulator (Electro-Optical Modulator), a Magneto-Optical Modulator (Magneto-Optical Modulator), an Acousto-Optical Modulator (AOM), and the like. The present invention does not limit the type and kind of the display chip 2.

The first lens group and the second lens group constitute an imaging optical path. Because the focal lengths of the first lens group and the second lens group are different, two pictures with different throw ratios are formed by the first lens group and the second lens group.

In this embodiment, the optical projection module includes a display chip 2. The display chip 2 has a first deflection angle a1 and a second deflection angle a 2. When the display chip 2 rotates to the first deflection angle a1 (positive first deflection angle a1), the display chip 2 may reflect the light rays incident thereon at the first angle to form a first light beam L1. When the display chip 2 rotates to the second deflection angle a2 (positive second deflection angle a2), the display chip 2 may reflect the light rays incident thereon at a second angle to form a second light beam L2. The first angle is the reflection angle of the first light beam L1 on the display chip 2, and the second angle is the reflection angle of the second light beam L2 on the display chip 2.

Since the first deflection angle a1 and the second deflection angle a2 are different, the reflection angle of the first light beam L1 on the display chip 2 is different from the reflection angle of the second light beam L2 on the display chip 2, so that the first light beam L1 and the second light beam L2 emitted from the display chip 2 do not overlap. Referring to fig. 1, the first and second light beams L1 and L2 are separated in the vertical direction. Wherein the thin lines represent the first light beam L1 and the thick lines represent the second light beam L2.

In this embodiment, the optical projection module comprises a dimming component 3. Wherein the dimming component 3 is located at the light exit side of the display chip 2. The dimming member 3 receives the first light beam L1 and the second light beam L2 emitted from the display chip 2. In addition, the light adjusting component 3 is also used for adjusting the emitting directions of the first light beam L1 and the second light beam L2 from the light adjusting component 3, so that the first light beam L1 and the second light beam L2 do not overlap after passing through the light adjusting component 3.

Specifically, the first light beam L1 emitted from the dimming member 3 is incident to the first lens group to form a first image having a first cast ratio. The second light beam L2 emitted from the dimming part 3 is incident to the second lens group to form a second image having a second cast ratio.

The first light beam L1 emitted from the dimming part 3 is incident to the first lens group, and a first image is displayed on the first display part. The second light beam L2 emitted from the dimming part 3 is incident to the second lens group, and a second image is displayed on the second display part.

Since the first lens group and the second lens group are different in focal length. The first projection ratio of the first image and the second projection ratio of the second image are different. The throw ratio is the ratio of the throw distance to the frame width. The throw ratio determines the distance between the optical projection module and the display component.

For example, the focal length of the first lens group is smaller than that of the second lens group, the first lens group can realize short-distance projection, and the second lens group can realize long-distance projection.

Wherein the first image and the second image may display the same picture, or the first image and the second image may display different pictures. For example, the first display member and the second display member may be a curtain, a table, a wall, or glass, etc.

In the embodiment of the present application, the display chip 2 rotates under the control of a time sequence (for example, a time sequence of control signals to be sent when a command is executed), so that the display chip 2 switches between the first deflection angle a1 and the second deflection angle a2, the display chip 2 forms a first light beam and a second light beam which are not overlapped with each other in combination with the dimming component 3, and further, the first lens group and the second lens group enable the optical projection module to simultaneously project a first image and a second image with different projection ratios, thereby implementing the switching of the far-distance and near-distance images. The far and near distance images are switched at high speed, and human eyes can see the first image and the second image to be displayed simultaneously by utilizing the visual pause principle of people.

In this embodiment, the first lens group and the second lens group can realize a large range of variation in the throw ratio by adjusting the focal lengths of the first lens group and the second lens group so that the virtual image distance can cover 0.5m to 50m, but the virtual image distance is not limited to this distance.

In an alternative embodiment, the display chip 2 further comprises a protective cover 21. The protective cover plate is a plane lens.

In one embodiment, the first lens group includes a first focusing lens and a first magnification-increasing mirror 51, the first magnification-increasing mirror 51 for receiving and transmitting a first light beam emitted from the first focusing lens;

the second lens group includes a second fixed focus lens and a second magnification-increasing mirror 52, and the second magnification-increasing mirror 52 is configured to receive and transmit the second light beam emitted from the second fixed focus lens.

The focal length of the first magnification-increasing mirror 51 and the focal length of the second magnification-increasing mirror 52 are different.

In this embodiment, the focal length of the first focus lens and the focal length of the second focus lens may be the same or different.

The first and second fixed focus lenses may be disposed on different sides or the same side of the dimming member 3. The first fixed focus lens and the second fixed focus lens are arranged on different sides of the light adjusting component 3, and the light adjusting component 3 modulates the first light beam L1 and the second light beam L2 to be emitted from different sides of the light adjusting component 3; the first and second fixed focus lenses are disposed on the same side of the dimming part, and the dimming part 3 modulates the first light velocity L1 and the second light beam L2 to be emitted from the same side of the dimming part 3.

In this embodiment, the first light beam L1 is incident on the first focusing lens and passes through the first magnification-increasing mirror 51, forming a first image having a first projection ratio; the second light beam L2 is incident on the second fixed focus lens and passes through the second magnification increasing mirror 52, forming a second image having a second projection ratio.

In one embodiment, referring to fig. 1, the optical projection module includes a fixed focus lens 4, a first magnification-increasing mirror 51 and a second magnification-increasing mirror 52; the fixed focus lens 4 and the first magnification-increasing lens 51 constitute the first lens group; the fixed-focus lens 4 and the second magnification-increasing mirror 52 constitute the second lens group.

In this embodiment, the fixed focus lens 4 is provided on the light outgoing side of the light adjusting member 3. The dimming member 3 modulates the first light beam L1 and the second light beam L2 to be emitted from the same side of the dimming member 3. The dimming element 3 projects both the first light beam L1 and the second light beam L2 to the fixed focus lens 4. The first light beam L1 and the second light beam L2 can be projected by using the same fixed focus lens 4.

The first light flux L1 emitted from the light adjustment member 3 is projected onto the fixed focus lens 4, and the first magnification-increasing mirror 51 is provided between the fixed focus lens 4 and the first display member. The first light flux L1 emitted from the fixed focus lens 4 passes through the first magnification-increasing mirror 51, and a first image is displayed on the first display unit.

The second light flux L2 emitted from the light adjustment member 3 is projected to the fixed focus lens 4, and the second magnification-increasing mirror 52 is provided between the fixed focus lens 4 and the second display member. The second light beam L2 emitted from the fixed focus lens 4 passes through the second magnification increasing mirror 52, and a second image is displayed on the second display unit.

In this embodiment, by adjusting the focal lengths of the first magnification-increasing mirror 51 and the second magnification-increasing mirror 52, the first magnification-increasing mirror 51 and the second magnification-increasing mirror 52 can realize a large range of variation in the projection ratio in cooperation with the fixed-focus lens 4, so that the virtual image distance can cover 0.5m to 50m, but the virtual image distance is not limited to this distance.

Since the focal lengths of the first multiplying mirror 51 and the second multiplying mirror 52 are different, that is, the multiplying times of the first multiplying mirror 51 and the second multiplying mirror 52 are different. The first image aspect ratio and the second image aspect ratio are different. The throw ratio is the ratio of the throw distance to the frame width. The throw ratio determines the distance between the optical projection module and the display component.

For example, the focal length of the first multiplying mirror 51 is smaller than that of the second multiplying mirror 52, the first multiplying mirror 51 can realize short-distance projection, and the second multiplying mirror 52 can realize long-distance projection.

In one embodiment, referring to fig. 5, the light adjusting part 3 includes a first reflector 61 disposed at a light-emitting side of the display chip 2 and an optical element 7 having diopter disposed at the light-emitting side of the first reflector 61.

Specifically, the dimming member 3 functions to reflect the first light beam L1 and the second light beam L2, and to modulate the propagation angle of the first light beam L1 and the propagation angle of the second light beam L2.

The light adjusting part 3 includes a first reflecting mirror 61 and an optical element 7 of diopter, wherein the first reflecting mirror 61 and the optical element 7 of diopter are two optical parts independent of each other. The optical element 7 of diopter may be a free-form surface mirror, for example.

The first reflecting mirror 61 reflects the first light beam L1 to the optical element 7 of diopter. The first light beam L1 travels to the fixed focus lens 4 through the optical element 7 of diopter. While the first mirror 61 reflects the second light beam L2 to the optical element 7 of diopter. The second light beam L2 travels to the fixed focus lens 4 through the optical element 7 of diopter.

In particular, the curved design of the optical element 7 of diopter enables compensation of the relative deflection angle of the first light beam L1 and the second light beam L2. The first light beam L1 and the second light beam L2 both exit from the diopter optical element 7 so that the first light beam L1 and the second light beam L2 are parallel light beams.

The first light beam L1 and the second light beam L2 are emitted from the diopter optical element 7 as two parallel light beams, and can receive two different light beams by using one fixed focus lens 4, and form two images with different projection ratios through the first magnification lens 51 and the second magnification lens 52 with different focal lengths. When the first light flux L1 and the second light flux L2 are emitted from the light adjustment member 3, the two light fluxes are emitted in different directions, which makes it inconvenient to install the focus lens 4. On the other hand, it is also not advantageous to reduce the size of the optical projection system.

In one embodiment, referring to fig. 1, 3 and 4, the dimming component 3 is a turning prism.

In particular, the embodiment realizes the reflection of the first light beam L1 and the second light beam L2 by the turning prism, and realizes the modulation of the propagation angle of the first light beam L1 and the modulation of the propagation angle of the second light beam L2 by the turning prism, so that the structure of the optical projection module is more compact.

The bending prism comprises an incident surface S3, a reflecting surface S1 and an emergent surface S2, wherein the incident surface S3 is positioned on the light emergent side of the working surface of the display chip 2, and the incident surface S3 is parallel to the working surface of the display chip 2; the exit surface S2 is located on the light exit side of the reflection surface S1.

The length of the incident surface S3 of the turning prism is determined by the two deflection angles of the display chip 2, the material of the turning prism, and the shape of the turning prism. For example, the light reflected from the display chip 2 enters the turning prism through the incident surface S3 of the device prism and propagates in the turning prism.

Specifically, the reflection angle of the light beam reflected from the display chip 2 is correlated with the deflection angle of the display chip 2. When the light beam reflected from the display chip 2 enters the turning prism to propagate, the propagation direction of the light beam is related to the material of the turning prism; the propagation direction of the light beam entering the turning prism through the incident surface S3 of the turning prism in the turning prism is related to the shape of the turning prism, and the angle of the light beam exiting from the turning prism is related to the material of the turning prism.

If the length of the incident surface S3 of the turning prism is too short, it is not favorable for the first light beam L1 and the second light beam L2 to enter the turning prism. If the length of the incident surface S3 of the turning prism is too long, it is not favorable to reduce the size of the optical projection module.

In a specific embodiment, referring to fig. 1, the dimming component 3 is a turning prism. The turning prism comprises a reflecting surface S1, an emergent surface S2 and an incident surface S3, wherein the reflecting surface S1, the emergent surface S2 and the incident surface S3 are all planar lenses. The incident surface S3 is located on the light emergent side of the working surface of the display chip 2, and the incident surface S3 is parallel to the working surface of the display chip 2; the exit surface S2 is located on the light exit side of the reflection surface S1.

The light emitted by the light emitting component 1 can transmit to the display chip 2 after passing through the reflecting surface S1 of the bending prism, the light reflected by the display chip 2 can transmit to the reflecting surface S1 of the bending prism through the incident surface S3 of the bending prism, the light is reflected from the reflecting surface S1 of the bending prism and transmitted to the emergent surface S2 of the bending prism, and the light is transmitted from the emergent surface S2 of the bending prism and transmitted to the fixed focus lens 4. Since the exit surface S2 of the bending prism is a planar lens, the first light beam L1 and the second light beam L2 exit from the bending prism and propagate in different directions.

In a specific embodiment, referring to fig. 3 and 4, the turning prism includes a reflecting surface S1, an exit surface S2 and an entrance surface S3, and at least one of the reflecting surface S1 and the exit surface S2 is non-planar.

Specifically, the incident surface S3 is located on the light exit side of the working surface of the display chip 2, and the incident surface S3 is parallel to the working surface of the display chip 2; the exit surface S2 is located on the light exit side of the reflection surface S1, and at least one of the reflection surface S1 and the exit surface S2 is a non-planar surface.

In one embodiment, the reflecting surface S1 of the turning prism is planar and the exit surface S2 of the turning prism is non-planar.

In yet another embodiment, the reflecting surface S1 of the turning prism is non-planar and the exit surface S2 of the turning prism is non-planar.

The non-planar curved design in the embodiment of the present application can compensate the relative deflection angle of the first light beam L1 and the second light beam L2. The first light beam L1 and the second light beam L2 both exit from the non-planar mirror, so that the first light beam L1 and the second light beam L2 are parallel light beams.

The first light beam L1 and the second light beam L2 are emitted from the non-planar mirror as two parallel light beams, and two different images with different projection ratios can be formed by using one fixed focus lens 4 to receive the two different light beams. When the first light beam L1 and the second light beam L2 are emitted from the light adjustment member 3, the two light beams are emitted and travel in different directions, which makes it inconvenient to install the focus lens 4. On the other hand, it is also not advantageous to reduce the size of the optical projection system.

In addition, the embodiment realizes the reflection of the first light beam L1 and the second light beam L2 by the turning prism, and realizes the modulation of the propagation angle of the first light beam L1 and the modulation of the propagation angle of the second light beam L2 by the turning prism, so that the structure of the optical projection module is more compact.

In one embodiment, referring to fig. 3 and 4, the optical projection module further includes a first mirror group located between the fixed-focus lens 4 and the first magnification-increasing mirror 51.

In one embodiment, referring to fig. 3 and 4, the optical projection module further includes a second mirror group, and the second mirror group is located between the fixed-focus lens 4 and the second magnification-increasing mirror 52.

Specifically, the first light beam L1 is imaged by the fixed focus lens 4 and reflected by the first mirror group to act on the first magnification increasing mirror 51. The position of the first mirror group is related to the position of the first display component, so that the image formed by the fixed-focus lens 4 reflects the first mirror group on the first multiplying mirror 51, and then is directly displayed on the first display component.

The second light beam L2 is imaged by the fixed focus lens 4 and then reflected by the second mirror group to act on the second magnification increasing mirror 52. The setting position of the second mirror group is related to the position of the second display component, so that the image formed by the fixed-focus lens 4 reflects the second mirror group on the second multiplying mirror 52, and then is directly displayed on the second display component.

For example, referring to fig. 3, the optical projection module is applied to synchronously display scenes of desktop projection and wall projection. The desktop setting position and the wall setting position are mutually perpendicular.

In the present embodiment, the first mirror group includes the second mirror 62, and the first light beam L1 is imaged by the fixed focus lens 4 and reflected by the second mirror 62 to act on the first magnification-increasing mirror 51. The first light beam L1 is used to project an image with a small throw ratio.

The second reflecting mirror group comprises a third reflecting mirror 63 and a fourth reflecting mirror 64, and the second light beam L2 is imaged by the fixed-focus lens 4, reflected by the third reflecting mirror 63 and acts on the fourth reflecting mirror 64, and reflected by the fourth reflecting mirror 64 and acts on the second multiplying mirror 52. The second light beam L2 is used to project an image with a large projection ratio.

The second reflector 62 and the third reflector 63 are arranged at an included angle, and the third reflector 63 and the fourth reflector 64 are arranged in parallel.

For example, referring to fig. 4, the optical projection module is applied to a synchronous display scene of HUD (head-up display) distance imaging. In HUD distance imaging, it is necessary to display both an image with a large projection ratio and an image with a small projection ratio in front of the vehicle. Information such as vehicle speed, oil amount, and rotation speed is projected and suspended on a hood or other optical components such as window glass; such as projecting road signs, routes, etc. in front of the vehicle.

In this embodiment, the first mirror group includes the second mirror 62 and the fifth mirror 65, and the first light beam L1 is imaged by the fixed focus lens 4 and then reflected by the second mirror 62 to act on the fifth mirror 65, and then reflected by the fifth mirror 65 to act on the first multiplying mirror 51. The first light beam L1 is used to project an image at a close distance.

The second reflecting mirror group comprises a third reflecting mirror 63 and a fourth reflecting mirror 64, and the second light beam L2 is imaged by the fixed-focus lens 4, reflected by the third reflecting mirror 63 and acts on the fourth reflecting mirror 64, and reflected by the fourth reflecting mirror 64 and acts on the second multiplying mirror 52. The second light beam L2 is used to project a distant image.

In an alternative embodiment, the fixed-focus lens 4 is an image-side telecentric lens.

In the embodiment, the image-side telecentric lens forms an image-side telecentric optical path. Because the lens in the image space telecentric lens is in an axisymmetric structure, the image space telecentric lens forms an axisymmetric image space telecentric light path. The first light beam L1 and the second light beam L2 are formed by being split by the illumination optical path. The split first light beam L1 and the split second light beam L2 are imaged by an axially symmetric image space telecentric optical path and then are respectively acted on the first multiplying lens 51 and the second multiplying lens 52 through a reflector group, so that images with different projection ratios are realized. In addition, the fixed-focus lens 4 in this embodiment adopts an image-side telecentric lens, which can improve the quality of a projection picture.

In an alternative embodiment, referring to fig. 1 and fig. 2, the optical projection module includes a digital micromirror controller, and the display chip 2 is a digital micromirror device;

the digital micromirror device has a plurality of micromirrors 22, and the digital micromirror controller controls the rotation of the micromirrors 22 to switch the micromirrors 22 between a first deflection angle A1 and a second deflection angle A2.

Specifically, the light beam emitted from the light emitting component 1 is irradiated onto the dmd, and the micromirror 22 array of the dmd is controlled by a dmd controller (not shown in the figure) to deflect, thereby modulating the angle of the light source, so that the dmd alternately reflects the first light beam L1 and the second light beam L2.

For example, a PWM (pulse width modulation) modulation value is stored in a digital micromirror controller, and the frame frequency of the digital micromirror device is modulated to a set range; the PWM modulation value corresponding to each micro lens 22 is correspondingly set, the opening times and the rotation angle of the opening frequency of the corresponding micro lens 22 are controlled, and the optical projection module simultaneously displays far and near projection images by utilizing the human eye visual persistence principle.

In one particular embodiment, the digital micromirror device comprises a plurality of micromirrors 22, the micromirrors 22 having a size ranging from 14 μm to 16 μm, and the digital micromirror device is typically arrayed with up to 50 to 200 ten thousand micromirrors 22. The micromirror 22 rotates around the hinge as a rotation axis, wherein the rotation angle is a first deflection angle a1 and a second deflection angle a 2. Specifically, the micromirror 22 is switched between the first deflection angle a1 and the second deflection angle a2 by timing control.

In the digital micromirror device, each micromirror 22 is an independent individual and can be flipped to a first deflection angle a1 (positive or negative) and a second deflection angle a2 (positive or negative), so that light received by the micromirror can be reflected at different angles.

The digital micromirror device has three stable states including an "on" state, an "off" state, and a no-signal state. Wherein the rotation angle of the dmd is the positive first deflection angle a1 or the positive second deflection angle a2, and the display chip 2 is in the "on" state. The digital micromirror device rotates by a negative first deflection angle a1 or a negative second deflection angle a2 and is in an "off" state. The rotation angle of the digital micromirror device is 0 deg., and the display chip 2 is in a no-signal state.

In an alternative embodiment, the difference between the first deflection angle A1 and the second deflection angle A2 is in the range of 10 to 15.

Specifically, the first deflection angle a1 and the second deflection angle a2 affect the reflection angle of the light beam on the display chip 2. For example, the display chip 2 rotates to the first deflection angle a1, the display chip 2 reflects the first light beam L1, and the reflection angle and the propagation direction of the first light beam L1 are related to the first deflection angle a1 of the display chip 2. The display chip 2 rotates to the second deflection angle a2, the display chip 2 reflects the second light beam L2, and the reflection angle and the propagation direction of the second light beam L2 are related to the second deflection angle a2 of the display chip 2.

For example, the difference between the first deflection angle a1 and the second deflection angle a2 is small, and the first light beam L1 and the second light beam L2 are not separated sufficiently, which affects the imaging effect of the first image and the second image. The difference between the first deflection angle a1 and the second deflection angle a2 is small, and the distance separating the first light beam L1 and the second light beam L2 is large, so that the light adjusting component 3 with a longer size is required to receive the first light beam L1 and the second light beam L2, which is not favorable for the reduction design of the optical projection module. The difference range between the first deflection angle A1 and the second deflection angle A2 is limited in the range, and the size of the optical projection module can be further reduced on the premise of not influencing the imaging effect of the first image and the second image.

In a specific embodiment, the first deflection angle a1 is ± 17 °, the second deflection angle a2 is ± 30 °, and when the display chip 2 is in the "on" state, the micro-mirror 22 of the display chip 2 needs to be polarized by +17 ° or +30 °, so the difference between the two in this embodiment is 13 °.

According to a second aspect of the embodiments of the present application, an electronic device is provided. The electronic equipment comprises the optical projection module of the first aspect.

Optionally, the electronic device is an illumination light machine or a head-up display. The electronic device is capable of displaying images of different throw ratios simultaneously. In addition, it should be noted that the electronic device provided in the embodiments of the present application includes, but is not limited to, the above-mentioned illumination light machine or head-up display, and may also be other types of electronic devices. For example, the electronic device is a smart wearable device.

In the above embodiments, the differences between the embodiments are described in emphasis, and different optimization features between the embodiments can be combined to form a better embodiment as long as the differences are not contradictory, and further description is omitted here in consideration of brevity of the text.

Although some specific embodiments of the present application have been described in detail by way of illustration, it should be understood by those skilled in the art that the above illustration is only for purposes of illustration and is not intended to limit the scope of the present application. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the present application. The scope of the application is defined by the appended claims.

Claims

1. An optical projection module, comprising: the dimming device comprises a display chip (2), a dimming part (3), a first lens group and a second lens group, wherein the focal length of the first lens group is different from that of the second lens group;

the display chip (2) has a first deflection angle and a second deflection angle, and the display chip (2) can rotate and switch between the first deflection angle and the second deflection angle;

the display chip (2) rotates to the state of the first deflection angle to form a first light beam;

the display chip (2) rotates to the second deflection angle state to form a second light beam;

the light adjusting component (3) is used for receiving and modulating the first light beam and the second light beam so that the first light beam is incident to the first lens group and the second light beam is incident to the second lens group.

2. The optical projection module as claimed in claim 1, wherein the first lens group comprises a first focusing lens and a first multiplying mirror, the first multiplying mirror is configured to receive and transmit the first light beam emitted from the first focusing lens;

the second lens group comprises a second fixed-focus lens and a second multiplying lens, and the second multiplying lens is used for receiving and transmitting a second light beam emitted from the second fixed-focus lens;

the focal length of the first multiplying mirror is different from that of the second multiplying mirror.

3. The optical projection module as claimed in claim 1, wherein the optical projection module comprises a fixed focus lens (4), a first multiplying mirror (51) and a second multiplying mirror (52), and the focal length of the first multiplying mirror (51) is different from the focal length of the second multiplying mirror (52);

the fixed-focus lens (4) and the first multiplying lens (51) form the first lens group;

the fixed-focus lens (4) and the second multiplying lens (52) form the second lens group.

4. The optical projection module as claimed in any one of claims 1 to 3, wherein the dimming component (3) comprises a first mirror (61) disposed on the light exit side of the display chip (2) and an optical element (7) having optical power disposed on the light exit side of the first mirror (61).

5. The optical projection module as claimed in any of claims 1 to 3, characterized in that the light-modulating component (3) is a turning prism.

6. The optical projection module of claim 5 wherein the turning prism comprises an entrance surface, a reflection surface and an exit surface, at least one of the reflection surface and the exit surface being non-planar.

7. The optical projection module of claim 3 further comprising a first set of mirrors located between the prime lens (4) and the first magnification power increasing mirror (51).

8. The optical projection module of claim 3, further comprising a second mirror group located between the fixed focus lens (4) and the second magnification-increasing mirror (52).

9. An electronic device, characterized in that the electronic device comprises an optical projection module according to any of claims 1-8.