Projection module and electronic device

Abstract

The present application discloses a projection module and an electronic device. The projection module includes a light source, a display reflector, and a lens group. The display reflector is configured to process light from the light source and reflect the light carrying image information toward the lens group. The lens group includes at least one concave lens, and the concave lens includes an incident light surface and an emergent light surface facing away from each other. The light from the display reflector enters the concave lens of the lens group through the incident light surface. The line connecting the center of the incident light surface and the center of the emergent light surface is the short axis direction of the concave lens, and the long axis direction of the concave lens is perpendicular to the short axis direction of the concave lens. The length of the concave lens in the long axis direction is greater than the length of the concave lens in the short axis direction. The lens group is configured to diffuse the light from the display reflector to increase the projection area of the image information. The present application utilizes the display reflector and the elongated concave lens to achieve miniaturization of the projection module, which is beneficial to integrating the projection module into the electronic device, and the electronic device can directly perform projection without an additional projection device.

Description

Technical Field

[0001] This application relates to the field of projection devices, and particularly to a projection module and an electronic device. Background Art

[0002] A projection device can project an image onto an external plane to enlarge the display screen for easy viewing by users. However, existing projection devices are usually standalone and have a relatively large volume, making them inconvenient to carry around at any time. Summary of the Invention

[0003] Embodiments of this application provide a projection module and an electronic device.

[0004] This application provides a projection module. Along the optical path, the projection module sequentially includes a light source, a display reflector, and a lens group. The light source is configured to emit light. The display reflector is configured to process the light from the light source and reflect the light carrying image information towards the lens group. The lens group includes at least one concave lens, and the concave lens includes an incident light surface and an exit light surface facing away from each other. The light from the display reflector enters the concave lens of the lens group through the incident light surface. The line connecting the center of the incident light surface and the center of the exit light surface is the short axis direction of the concave lens. The long axis direction of the concave lens is perpendicular to the short axis direction of the concave lens, and the length of the concave lens in the long axis direction is greater than the length of the concave lens in the short axis direction. The lens group is configured to diffuse the light from the display reflector to increase the projection area of the image information.

[0005] This application also provides an electronic device. The electronic device includes a housing and a projection module, and the projection module is combined with the housing. Along the optical path, the projection module sequentially includes a light source, a display reflector, and a lens group. The light source is configured to emit light. The display reflector is configured to process the light from the light source and reflect the light carrying image information towards the lens group. The lens group includes at least one concave lens, and the concave lens includes an incident light surface and an exit light surface facing away from each other. The light from the display reflector enters the concave lens of the lens group through the incident light surface. The line connecting the center of the incident light surface and the center of the exit light surface is the short axis direction of the concave lens. The long axis direction of the concave lens is perpendicular to the short axis direction of the concave lens, and the length of the concave lens in the long axis direction is greater than the length of the concave lens in the short axis direction. The lens group is configured to diffuse the light from the display reflector to increase the projection area of the image information.

[0006] The projection module and the electronic device according to the embodiments of the present application utilize a display reflector to form light rays with image information, and use an elongated concave lens to magnify the light rays reflected by the display reflector, and finally project a larger area of image information. This projection structure is beneficial to reducing the volume of the entire projection module, so that the projection module can be easily integrated into the electronic device. In this way, there is no need to carry an additional independent projection device with a large volume, and the electronic device can directly implement the projection function.

[0007] Additional aspects and advantages of the embodiments of the present application will be given in part in the following description, will become apparent in part from the following description, or will be understood through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0009] Figure 1 is a schematic perspective view of a projection module according to an embodiment of the present application;

[0010] Figure 2 is a schematic optical path diagram of a projection module according to an embodiment of the present application;

[0011] Figure 3 is a schematic perspective view of another projection module according to an embodiment of the present application;

[0012] Figure 4 is a schematic perspective view of an electronic device according to an embodiment of the present application;

[0013] Figure 5 is an exploded schematic view of the structure of an electronic device according to an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0014] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the drawings, in which the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the embodiments of the present application and should not be construed as limiting the embodiments of the present application.

[0015] The projection device can project an image onto an external plane to enlarge the display screen for the convenience of the user to view. However, the existing projection devices are usually independent and have a large volume, which is not convenient to carry around.

[0016] To solve the above problems, please refer to Figure 1 and Figure 2, this application provides a projection module 10. The projection module 10 includes a light source 11, a display reflector 12, and a lens group 13, and the light source 11, the display reflector 12, and the lens group 13 are arranged along the optical path of the projection module 10. The light source 11 is used to emit light. The display reflector 12 is used to process the light from the light source 11 and reflect the light with image information toward the lens group 13. The lens group 13 includes at least one concave lens 130. The concave lens 130 includes an incident light surface 1301 and an exit light surface 1302 facing away from each other. The light from the display reflector 12 enters the concave lens 130 of the lens group 12 through the incident light surface 1301. The connection line between the center of the incident light surface 1301 and the center of the exit light surface 1302 is the short axis direction D1 of the concave lens 130. The long axis direction D2 of the concave lens 130 is perpendicular to the short axis direction D1 of the concave lens 130. The length of the concave lens 130 in the long axis direction D2 is greater than the length of the concave lens 130 in the short axis direction D1. The lens group 13 is used to diffuse the light from the display reflector 12 to increase the projection area of the image information.

[0017] Please refer to Figure 1 , Figure 4 and Figure 5 , this application also provides an electronic device 100. The electronic device 100 includes a housing 20 and a projection module 10. The projection module 10 includes a light source 11, a display reflector 12, and a lens group 13, and the light source 11, the display reflector 12, and the lens group 13 are arranged along the optical path of the projection module 10. The light source 11 is used to emit light. The display reflector 12 is used to process the light from the light source 11 and reflect the light with image information toward the lens group 13. The lens group 13 includes at least one concave lens 130. The concave lens 130 includes an incident light surface 1301 and an exit light surface 1302 facing away from each other. The light from the display reflector 12 enters the concave lens 130 of the lens group 12 through the incident light surface 1301. The connection line between the center of the incident light surface 1301 and the center of the exit light surface 1302 is the short axis direction D1 of the concave lens 130. The long axis direction D2 of the concave lens 130 is perpendicular to the short axis direction D1 of the concave lens 130. The length of the concave lens 130 in the long axis direction D2 is greater than the length of the concave lens 130 in the short axis direction D1. The lens group 13 is used to diffuse the light from the display reflector 12 to increase the projection area of the image information.

[0018] The projection module 10 and the electronic device 100 according to the embodiments of the present application use the display reflector 12 to form light rays with image information, and use the elongated concave lens 130 to magnify the light rays reflected by the display reflector 12, and finally project a larger area of image information. This projection structure is beneficial to reducing the volume of the entire projection module 10, so that the projection module 10 can be easily integrated into the electronic device 100. In this way, there is no need to carry an additional independent and large-volume projection device, and the electronic device 100 can directly implement the projection function.

[0019] The projection module 10 according to the embodiments of the present application will be further described below with reference to the accompanying drawings.

[0020] Please refer to Figure 1 and Figure 2 , the projection module 10 includes a light source 11, a display reflector 12 and a lens group 13, and the light source 11, the display reflector 12 and the lens group 13 are arranged in sequence along the optical path of the projection module 10.

[0021] The light source 11 is used to emit light rays. In some embodiments, the light source 11 emits light at a predetermined light-emitting cycle, and within a predetermined light-emitting cycle, the light source 11 alternately emits light rays of different colors. For example, the light source 11 alternately emits red light, green light and blue light within a predetermined light-emitting cycle (the emission order of the three-color light rays is not limited here); or, the light source 11 alternately emits red light, blue light and yellow light within a predetermined light-emitting cycle (the emission order of the three-color light rays is not limited here), etc. Since the light source 11 can alternately emit light rays of different colors within a predetermined light-emitting cycle, multiple different-color light rays can be mixed to form a certain specific-color light ray, so that the projection module 10 can project a color image.

[0022] The display emission plate 12 is used to process the light rays from the light source 11 and reflect the light rays with image information toward the lens group 13. Specifically, the display reflector 12 includes a plurality of micro mirrors, and one micro mirror can be regarded as a pixel. When the display emission plate 12 receives the micro mirrors in a plurality of pixels to perform different degrees of reflection on the incident light rays, light rays with image information are formed and reflected toward the lens group 13.

[0023] Please refer to Figure 1 , the lens group 13 is used to diffuse the light rays with image information from the display reflector 12 to increase the projection area of the image information. Specifically, the lens group 13 includes a concave lens 130, and the concave lens 130 includes an incident light surface 1301 and an exit light surface 1302 arranged opposite to each other. The light rays with image information from the display reflector 12 enter the concave lens 130 from the incident light surface 1301 of the concave lens 130 and exit from the exit light surface 1302 of the concave lens 130.

[0024] The concave lens 130 is strip-shaped. Specifically, the line connecting the center point of the light incident surface 1301 of the concave lens 130 and the center point of the light exit surface 1302 of the concave lens 130 is the minor axis direction D1; the major axis direction D2 of the concave lens 130 is perpendicular to the minor axis direction D1 of the concave lens 130, and the length of the concave lens 130 in the major axis direction D2 is greater than the length of the concave lens 130 in the minor axis direction D1. The curvature of the concave lens 130 in the minor axis direction D1 is zero, that is, the concave lens 130 is smooth in the minor axis direction D1; the curvature of the concave lens 130 in the major axis D2 direction is not zero, that is, the concave lens 130 is arc-shaped in the major axis D2 direction. Specifically, for the cross-sectional area of the concave lens 130 along the minor axis direction, the cross-sectional area at the center of the concave lens 130 is the smallest, and the cross-sectional area at both ends of the concave lens 130 is the largest. Since the concave lens 130 has curvature only in the major axis direction D2 and has no curvature in the minor axis direction D1, the lens group 13 can not only magnify the image information incident on the concave lens 130 by the display reflector 12 in the major axis direction D2, but also reduce the height of the lens group 13, thereby reducing the height of the projection module 10, which is beneficial to integrating the projection module 10 into the electronic device 100( Figure 4 as shown).

[0025] In some embodiments, the lens group 13 includes a plurality of concave lenses 130. Along the light exit direction, the plurality of concave lenses 130 are arranged in sequence, and the lengths of the plurality of concave lenses 130 in the major axis direction D2 increase in sequence. For example Figure 1 and Figure 2In the embodiment, the number of the concave lenses 130 is three, and each concave lens 130 has an incident light surface and an emergent light surface. Specifically, the concave lenses 130 include a first concave lens 131, a second concave lens 132, and a third concave lens 133 arranged in sequence along the light emergent direction. The first concave lens 131 includes a first incident light surface 1312 and a first emergent light surface 1314. The second concave lens 132 includes a second incident light surface 1322 and a second emergent light surface 1324. The third concave lens 133 includes a third incident light surface 1332 and a third emergent light surface 1334. And the length of the second concave lens 132 in the long axis direction D2 is longer than the length of the first concave lens 131 in the long axis direction D2; the length of the third concave lens 133 in the long axis direction D2 is longer than the length of the second concave lens 132 in the long axis direction D2. That is to say, the light rays with image information from the display reflector 12 first enter the first concave lens 131 from the first incident light surface 1312. The first concave lens 131 performs the first diffusion on the incident light rays. The diffused light rays exit from the first emergent light surface 1314 and enter the second concave lens 132. After the second incident light surface 1322 of the second concave lens 132 receives the incident light rays, it performs the second diffusion on the incident light rays. The diffused light rays exit from the second emergent light surface 1324 and enter the third concave lens 133. After the third incident light surface 1332 of the third concave lens 133 receives the incident light rays, it performs the third diffusion on the incident light rays. The diffused light rays are emitted from the third emergent light surface 1332 to increase the projection area of the image information, thereby realizing the projection function.

[0026] Since the lens group 13 includes multiple concave lenses 130, the light rays with image information from the display reflector 12 form a projection picture after multiple diffusions by the multiple concave lenses 130, which not only increases the cross-sectional area of the projection picture, but also reduces the spherical aberration distortion caused by magnification and reduction, thereby improving the projection effect of the projection module 10.

[0027] In summary, the projection module 10 of the embodiment of the present application uses the display reflector 12 to form light rays with image information, and uses the strip-shaped concave lenses 130 to realize the magnification of the light rays reflected by the display reflector 12, and finally projects a larger area of image information. This projection structure is beneficial to reducing the volume of the entire projection module 10, so that the projection module 10 can be easily integrated into the electronic device 100. In this way, there is no need to carry an additional independent and large-volume projection device, and the electronic device 100 can directly realize the projection function.

[0028] In some embodiments, please combine Figure 1 and Figure 2, the light source 11 can emit light of only one color, for example, white light. The display emission plate 12 includes a plurality of reflection units (not shown in the figure), and each reflection unit includes a plurality of micro - mirrors (not shown in the figure). The plurality of micro - mirrors within the same reflection unit can reflect light of different colors. Thus, one reflection unit can be regarded as a pixel. When the light emitted by the light source 11 is incident on this pixel, the pixel can reflect the light of a specific color formed by mixing light of multiple colors. Thus, the light reflected by a plurality of pixels is the light carrying image information. As an example, three micro - mirrors can be included within the same reflection unit. One micro - mirror can reflect red light, another micro - mirror can reflect blue light, and the remaining micro - mirror can reflect green light. By different degrees of reflection of red light, blue light, and green light by each reflection unit, a certain specific color of light is mixed and formed. As another example, three micro - mirrors can be included within the same reflection unit. One micro - mirror can reflect red light, another micro - mirror can reflect blue light, and the remaining micro - mirror can reflect yellow light. By different degrees of reflection of red light, blue light, and yellow light by each reflection unit, a certain specific color of light is mixed and formed.

[0029] In some embodiments, the lens group 13 includes only one concave lens 130. Please refer to Figure 3 , specifically, the light carrying image information from the display reflection plate 12 enters the concave lens 130 through the incident light surface 1301 of the one concave lens 130. The concave lens 130 diffuses the incident light and emits it from the exit light surface 1302. Since there is only one concave lens 130 in the lens group 13, the volume and manufacturing cost of the projection module 10 can be minimized while the projection function can be achieved.

[0030] Please refer to Figure 4 and Figure 5 , this application also provides an electronic device 100. The electronic device 100 includes a housing 20 and the projection module 10 described in any of the above embodiments. The housing 20 is combined with the projection module 10.

[0031] Please refer to Figure 5, the housing 20 is provided with a projection window 21, and the opening position of the projection window 21 corresponds to the projection module 10, so that the light with image information projected by the projection module 10 is projected to the outside through the projection window 21. In some embodiments, the area of the projection window 21 is larger than the cross-sectional area of the light with image information projected by the projection module 10 at the projection window 21, so as to avoid the housing 20 blocking the light, that is, all the light with image information can be emitted from the projection window 21. Of course, the area of the projection window 21 may also be equal to the cross-sectional area of the light with image information projected by the projection module 10 at the projection window 21, which is not limited herein.

[0032] Please refer to Figure 4 , in some embodiments, the electronic device 100 further includes a light-transmitting member 30. The light-transmitting member 30 is installed on the projection window 21 to seal the projection window 21. It should be noted that the light-transmitting member 30 may be transparent plastic, transparent glass, etc., as long as it is light-transmitting (here, light mainly refers to visible light) and the light transmittance exceeds a predetermined threshold (the predetermined threshold is, for example, 75%, 80%, 85%, 90%, 95% or 100% etc.), which is not limited herein. Since the light-transmitting member 30 seals the projection window 21, while satisfying the requirement of allowing the light projected by the projection module 10 to be emitted to the outside, it can also prevent other impurities such as dust from entering the interior of the electronic device 100, so as to improve the service life of the electronic device 100.

[0033] Please continue to refer to Figure 4 and Figure 5 , the housing 20 includes a first surface 41 and a second surface 42 opposite to each other, and a plurality of side surfaces 43 connecting the first surface 41 and the second surface 42. Among them, a display screen 60 is installed on the first surface 41.

[0034] The plurality of side surfaces 43 include a first side surface 431, a second side surface 432, a third side surface 433 and a fourth side surface 434. The first side surface 431 and the third side surface 433 are opposite to each other, and the second side surface 432 and the fourth side surface 434 are opposite to each other, and are all used to connect the first side surface 431 and the third side surface 433. The first side surface 431 is provided with the projection window 21, and the light-emitting surface 1302 of the concave lens 130 in the projection module 10 faces the first side surface 431 of the electronic device 100, that is, the projection module 10 projects the light with image information in the direction of the first side surface 431 of the electronic device 100, so that the light with image information projected by the projection module 10 can be projected to the outside through the projection window 21.

[0035] It should be noted that in other examples, the projection window 21 can also be opened on any one of the first surface 41, the second surface 42, the second side surface 432, the third side surface 433, and the fourth side surface 434 of the electronic device 100. For example, the projection window 21 can be opened on the first surface 41; or, the projection window 21 can be opened on the second surface 42; or, the projection window 21 can be opened on the second side surface 432, etc., as long as it is ensured that the light projected by the projection module 10 can be emitted from the projection window 21, and there is no limitation here.

[0036] Please refer to Figure 5 , in some embodiments, the electronic device 100 further includes a depth camera module 50. The depth camera module 50 includes a transmitter 51 and a receiver 52. An emission window 22 corresponding to the transmitter 51 and a reception window 23 corresponding to the receiver 52 are further opened on the housing 20. The emission window 22 and the reception window 23 are disposed on the same surface of the electronic device 100 as the projection window 21. Among them, the depth camera module 50 can be a structured light depth camera module or a time-of-flight depth camera module, and there is no limitation here. Exemplarily, the depth camera module 50 is a structured light depth camera module. The structured light emitted by the transmitter 51 passes through the emission window 22 and is emitted to the outside. When the structured light is blocked by an object such as a finger and then reflected, the emitted structured light passes through the reception window 23 and enters the receiver 52. After receiving the light, the receiver 52 forms a speckle image. The electronic device 100 can calculate a depth image using the speckle image and use the depth image to assist in detecting the position of an object such as a finger and gesture recognition, etc. The electronic device 100 can determine the position where the finger touches the image projected by the projection module 10 on the external plane through the finger position detection. This touch can be regarded as a user operation instruction, and the electronic device 100 can respond to the user operation instruction. In this way, while the electronic device 100 realizes the projection function, the user can also control the electronic device 100 by operating on the image projected by the projection module 10.

[0037] In some embodiments, the emission window 22 and the reception window 23 are respectively disposed on opposite sides of the projection window 21, that is, the projection window 21 is disposed between the emission window 22 and the reception window 23. Since the projection window 21 is disposed between the emission window 22 and the reception window 23, the picture projected by the projection module 10 can be completely within the viewing angle range of the light emitted by the transmitter 51 and the viewing angle range of the light received by the receiver 52, so that any occluder on the picture projected by the projection module 10 can be captured by the structured light module 50, ensuring the stability of the interaction.

[0038] In some embodiments, the emission window 22 and the reception window 23 may also be disposed on the same side of the projection window 21. In this case, the viewing angle difference between the emitter 51 and the receiver 52 is relatively small, and the accuracy of touch position recognition is relatively high, which is conducive to improving the accuracy of interaction.

[0039] In the projection module 10 of the electronic device 100 according to the embodiment of the present application, the display reflector 12 is used to form light rays with image information, and the elongated concave lens 130 is used to magnify the light rays reflected by the display reflector 12, and finally project a larger area of image information. This projection structure is conducive to reducing the volume of the entire projection module 10, so that the projection module 10 can be easily integrated into the electronic device 100. In this way, there is no need to carry an additional independent projection device with a large volume, and the electronic device 100 can directly implement the projection function.

[0040] In the description of this specification, the descriptions with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, without conflict, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0041] Any process or method description shown in the flowchart or described in other ways herein may be understood to represent a module, segment or portion of code including one or more executable instructions for implementing a specific logical function or process. The scope of the preferred embodiments of the present application includes additional implementations, where the functions may be executed in a substantially simultaneous manner or in a reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of the present application belong.

[0042] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present application.

Claims

1. An electronic device, characterized in that, It includes a housing and a projection module. The projection module is combined with the housing. Along the optical path, the projection module sequentially includes a light source, a display reflector, and a lens group; The light source is used to emit light; the display reflector is used to process the light from the light source and reflect the light with image information toward the lens group; The lens group includes at least one concave lens. The concave lens includes an incident light surface and an exit light surface facing away from each other. The light from the display reflector enters the concave lens of the lens group through the incident light surface. The connection line between the center of the incident light surface and the center of the exit light surface is the short axis direction of the concave lens. The long axis direction of the concave lens is perpendicular to the short axis direction of the concave lens. The length of the concave lens in the long axis direction is greater than the length of the concave lens in the short axis direction. The lens group is used to diffuse the light from the display reflector to increase the projection area of the image information; The concave lens is smooth in the short axis direction and arc-shaped in the long axis direction. The long axis direction of the concave lens corresponds to the length direction of the electronic device; The housing is provided with a projection window corresponding to the projection module. The light projected by the projection module exits to the outside through the projection window. The housing includes a first surface, a second surface, and a plurality of side surfaces connecting the first surface and the second surface. The first surface and the second surface face away from each other. A display screen is installed on the first surface. The projection window is opened on one of the side surfaces; The number of the concave lenses includes a plurality. Along the light exit direction, the plurality of concave lenses are arranged in sequence, and the lengths of the plurality of concave lenses in the long axis direction increase in sequence.

2. The electronic device according to claim 1, wherein The display reflector includes a plurality of reflection units. Each reflection unit includes a plurality of micro reflectors. The plurality of micro reflectors in the same reflection unit can reflect light of different colors.

3. The electronic device according to claim 1, wherein The light source emits light at a predetermined light emission period. Within one predetermined light emission period, the light source alternately emits light of different colors.

4. The electronic device according to claim 1, characterized in that The area of the projection window is larger than the cross-sectional area of the light at the projection window.

5. The electronic device according to claim 4, wherein The electronic device further includes a light transmissive member. The light transmissive member is installed on the projection window to seal the projection window.

6. The electronic device according to claim 4, wherein The electronic device further includes a depth camera module. The depth camera module includes a transmitter and a receiver. The housing is provided with a transmission window corresponding to the transmitter and a reception window corresponding to the receiver. The transmission window and the reception window are opened on the same surface as the projection window.

7. The electronic device according to claim 6, wherein The transmission window and the reception window are respectively located on opposite sides of the projection window.

8. The electronic device according to claim 6, wherein The transmission window and the reception window are located on the same side of the projection window.

Images