Projection device, display device and vehicle

Abstract

Embodiments of the present application provide a projection device, a display device and a vehicle, and relate to the technical field of display. The projection device comprises an image source, a projection lens, a curved mirror and a diffusion element. The image source is located at the light entrance side of the projection lens, the curved mirror is located at the light exit side of the projection lens, and the diffusion element is arranged between the image source and the curved mirror along the optical axis direction of the projection lens. In a plane perpendicular to the optical axis direction, the orthographic projection of the diffusion element does not coincide with the orthographic projection of the projection lens. The projection lens is used for projecting the image light generated by the image source to the curved mirror, the curved mirror reflects the image light emitted by the projection lens to the diffusion element, and the diffusion element diffuses the image light from the curved mirror. In this way, it can ensure that the user can see the image in strong light, and the projection device has the characteristics of good imaging quality and small size.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a projection device, display equipment, and vehicle. Background Technology

[0002] With the development of intelligent vehicle technology, head-up displays (HUDs) are installed in vehicles to improve driving safety. A HUD typically consists of a picture generation unit (PGU) and an optical system (mainly composed of various optical components, such as diffusers and light reflectors). The picture generation unit generates the image light to form an image and projects it outwards. The optical system processes the image light projected by the picture generation unit, performing folding, magnification, and other processing. However, while ensuring image quality, HUDs tend to be relatively large. Utility Model Content

[0003] This application provides a projection device, a display device, and a vehicle that can ensure users can see images under strong light, and also enable the projection device to have the characteristics of good image quality and small size.

[0004] A first aspect of this application provides a projection device including an image source, a projection lens, a curved reflector, and a diffuser. The image source is located on the light-inlet side of the projection lens, the curved reflector is located on the light-outlet side of the projection lens, and the diffuser is disposed between the image source and the curved reflector along the optical axis of the projection lens. In a plane perpendicular to the optical axis, the orthographic projection of the diffuser does not coincide with the orthographic projection of the projection lens. The projection lens projects image light generated by the image source onto the curved reflector, the curved reflector reflects the image light emitted from the projection lens to the diffuser, and the diffuser diffuses the image light from the curved reflector.

[0005] In this embodiment, by converging the image light emitted from the projection lens through a curved reflector, the image light received by the diffuser element can be increased, thereby increasing the image light projected to the human eye by the diffuser element, and thus improving the image light received by the human eye, ensuring that the user can see the image under strong light. Furthermore, by positioning the diffuser element along the optical axis between the image source and the curved reflector, the size of the projection device in the optical axis direction can be reduced, contributing to a smaller overall size. In addition, the cooperation of the projection lens, curved reflector, and diffuser element enables short-distance projection (ultra-short-throw projection), and also gives the projection device characteristics of high image quality and low distortion.

[0006] In some possible implementations, the diffusion element is positioned along the optical axis between the light-inlet side and the light-outlet side of the projection lens.

[0007] This avoids the distance between the vertex of the curved mirror and the diffusion element along the optical axis being too large or too small, effectively balancing the size of the diffusion element and the display area in the direction perpendicular to the optical axis, and ensuring imaging quality and miniaturization of the projection device.

[0008] In some possible implementations, the projection lens includes a first lens group, an aperture, and a second lens group arranged along the optical axis of the projection lens. The first lens group is close to the curved mirror, and the second lens group is close to the image source. Both the first and second lens groups include at least four lenses arranged along the optical axis of the projection lens.

[0009] In this way, while achieving a small-sized projection device, the image quality can be further improved and distortion reduced.

[0010] In some possible implementations, the first lens group has six lenses and the second lens group has six lenses.

[0011] In this way, while ensuring the compact design of the projection device, the image quality and display effect can be further improved.

[0012] In some possible implementations, the projection lens satisfies the relationship: -3≤EFL1 / L≤3. Where EFL1 is the focal length of the first lens group, and L is the distance from the vertex of the curved mirror along the optical axis to the diffuser element.

[0013] This effectively balances the distance between the vertex of the curved mirror and the diffusion element with the imaging quality, resulting in a smaller distance between the vertex of the curved mirror and the diffusion element, which helps to further reduce the size of the projection device.

[0014] In some possible implementations, the projection lens satisfies the relationship: -1.3≤EFL1 / L≤0.9.

[0015] This allows for a further reduction in the size of the projection device while ensuring that the image quality meets the requirements.

[0016] In some possible implementations, the projection lens satisfies the relationship: -200mm≤EFL1≤200mm.

[0017] This allows for a short optical path design for the first lens group, which helps reduce the size of the projection device and ensures image quality.

[0018] In some possible implementations, the projection lens satisfies the relationship: -0.5 ≤ EFL2 / L ≤ -0.1, where EFL2 is the focal length of the second lens group.

[0019] In this way, while ensuring image quality, the distance between the vertex of the curved mirror and the diffusion element can be reduced, which can further reduce the size of the projection device.

[0020] In some possible implementations, the projection lens satisfies the relationship: -35mm≤EFL2≤-10mm.

[0021] This allows for a short optical path design for the second mirror group, which helps reduce the size of the projection device and ensures image quality.

[0022] In some possible implementations, the projection device satisfies the relationship: 100mm≤L≤120mm.

[0023] This design allows for a small distance between the diffuser element and the vertex of the curved mirror, while effectively balancing the relationship between the size of the diffuser element, the imaging quality, and the projection device. This results in high imaging quality, a small projection device size, and a relatively large diffuser element size.

[0024] In some possible implementations, the projection device satisfies the relationship: 123mm ≤ IMH1 ≤ 369mm. Here, IMH1 is the distance between the top of the diffuser element and the optical axis of the projection lens in a direction perpendicular to the optical axis.

[0025] This allows for a smaller size design for the projection device in the direction perpendicular to the optical axis, which helps reduce the size of the projection device and the space required to install it.

[0026] In some possible implementations, the projection device satisfies the relationship: 33mm ≤ IMH2 ≤ 99mm. Here, IMH2 is the distance between the bottom of the diffuser element and the optical axis of the projection lens in a direction perpendicular to the optical axis.

[0027] This allows for a small-pitch design between the diffuser element and the projection lens in the direction perpendicular to the optical axis, further reducing the size of the projection device in the direction perpendicular to the optical axis, thereby further reducing the size of the projection device.

[0028] In some possible implementations, the image source includes a light source and a modulation device, which modulates the light emitted by the light source to obtain image light that includes image information.

[0029] In some possible implementations, the modulation device is any one of a liquid crystal display, a liquid crystal on silicon, a digital micromirror device, or a thin-film transistor.

[0030] A second aspect of this application provides a display device, which includes a processor and a projection device as described in any of the first aspects. The processor is configured to send image data to an image source of the projection device so that the image source generates image light.

[0031] A third aspect of this application provides a means of transportation that includes a projection device as described in the first aspect.

[0032] In some possible implementations, the vehicle also includes a windshield and a dashboard, and the projection device includes an image generating device and a diffusion element. The image generating device includes an image source, a projection lens, and a curved reflector, and is fixedly connected to the surface of the dashboard, while the diffusion element is disposed on the windshield.

[0033] In this way, the projection device constitutes a panoramic head-up display device, which can project vehicle information (such as speed, navigation, etc.) onto the windshield in a panoramic driving view, so that the driver can obtain the projected information without looking down, thereby improving driving safety and interactive experience.

[0034] In some possible implementations, the diffuser element is disposed inside the windshield, or the diffuser element is disposed on the surface of the windshield. Attached Figure Description

[0035] Figure 1 This is a schematic diagram illustrating an application scenario of the projection device provided in an embodiment of this application;

[0036] Figure 2 for Figure 1 A schematic diagram of the projection device in the diagram;

[0037] Figure 3 This is a schematic diagram of the structure of a projection device provided in Embodiment 1 of this application;

[0038] Figure 4 for Figure 3 A spherical chromatic aberration diagram of the projection lens in the image;

[0039] Figure 5 for Figure 3 Image scattering curve of the projection lens in the image;

[0040] Figure 6 for Figure 3 The distortion diagram of the projection lens in the image;

[0041] Figure 7 This is a schematic diagram of the structure of a projection device provided in Embodiment 2 of this application;

[0042] Figure 8 for Figure 7 A spherical chromatic aberration diagram of the projection lens in the image;

[0043] Figure 9 for Figure 7 Image scattering curve of the projection lens in the image;

[0044] Figure 10 for Figure 7 The distortion diagram of the projection lens in the image.

[0045] Explanation of reference numerals in the attached figures:

[0046] 100. Projection device;

[0047] 110. Image source; 111. Light source; 112. Modulation device; 113. Cover glass;

[0048] 120. Projection lens; 121. First lens group; 122. Second lens group; 123. Aperture stop;

[0049] 130. Curved surface mirror;

[0050] 140. Diffusion element;

[0051] 150. Image generating apparatus;

[0052] G1, First lens; G2, Second lens; G3, Third lens; G4, Fourth lens; G5, Fifth lens; G6, Sixth lens; G7, Seventh lens; G8, Eighth lens; G9, Ninth lens; G10, Tenth lens; G11, Eleventh lens; G12, Twelfth lens. Detailed Implementation

[0053] The terminology used in the implementation section of this application is for the purpose of explaining specific embodiments of this application only, and is not intended to limit this application.

[0054] To facilitate understanding, the relevant technical terms involved in the embodiments of this application will first be explained and described.

[0055] Focal length, also known as focal length, is a measure of the convergence or divergence of light in an optical system. It refers to the vertical distance from the optical center of a lens or lens group to the focal plane when a scene at infinity is formed into a clear image on the focal plane.

[0056] The image side is the side where the image is located, with the lens as the boundary. The side of the lens facing the image side is the image-side surface of the lens.

[0057] The object side is the side where the modulation device (e.g., DMD) is located, and the side of the lens facing the object side is the object side surface.

[0058] Optical power characterizes the ability of a lens to refract an incident parallel beam of light.

[0059] Positive focal length means that the lens has a positive focal length and has the effect of converging light.

[0060] Negative optical power means that the lens has a negative focal length, which has the effect of diverging light.

[0061] Axial chromatic aberration, also known as longitudinal chromatic aberration or positional chromatic aberration, occurs when a beam of light parallel to the optical axis converges at different positions after passing through a lens. This aberration is called positional chromatic aberration or axial chromatic aberration. This is because the lens images different wavelengths of light at different positions, causing the images of different colors of light to not completely overlap during the final imaging process, resulting in the dispersion of polychromatic light.

[0062] Distortion, also known as image distortion, refers to the degree of distortion in the image formed by an optical system relative to the object itself. Distortion occurs due to aperture aberration; the height of the intersection point between the principal ray from different fields of view and the Gaussian image plane after passing through the optical system is not equal to the ideal image height, and this difference is the distortion. Therefore, distortion only changes the imaging position of an off-axis object point on the ideal plane, causing distortion in the image shape, but it does not affect the image's sharpness.

[0063] This application provides a projection device 100, a display device, and a vehicle. The vehicle can be a car, truck, motorcycle, bus, ship, airplane, helicopter, lawnmower, recreational vehicle, amusement park vehicle, construction equipment, tram, golf cart, train, or handcart, etc., and is not particularly limited in this application.

[0064] Display devices can include head-up displays (HUDs), projectors, and in-vehicle displays. Among them, head-up displays can be windshield (W) HUDs, augmented reality (AR) HUDs, and PHUDs (panoramic head-up displays).

[0065] When the display device is a head-up display (HUD), it projects vehicle status information, external object indicators, and navigation information into the driver's field of vision, avoiding the need for the driver to look down and improving driving safety. Status information includes, but is not limited to, vehicle speed, mileage, fuel level, coolant temperature, and headlight status. External object indicators include, but are not limited to, safe following distance, surrounding obstacles, and reversing camera information. Navigation information includes, but is not limited to, directional arrows, distance, and travel time.

[0066] In some embodiments, the display device includes a processor and a projection device 100, wherein the processor is configured to send image data to the projection device 100 so that the projection device 100 generates image light.

[0067] The processor can be referred to as a front-end processor. A processor includes one or more processing units, such as: an application processor (AP), a modem processor, a graphics processing unit (GPU), an image signal processor (ISP), a controller, a video codec, a digital signal processor (DSP), a baseband processor, and / or a neural network processing unit (NPU). These different processing units can be independent devices or integrated into one or more processors.

[0068] It should be noted that, in addition to the projection device 100 and processor mentioned above, the display device may also include other components. For example, the display device may also include a power module, a wireless communication module, an I / O interface, and other components.

[0069] It should also be noted that in some embodiments, when the display device is applied to a vehicle, the display device may also remove the processor. In this case, the projection device 100 can be controlled by the vehicle controller to generate image light.

[0070] In related technologies, the projection device is a head-up display (PHUD) device. The PHUD is installed on the surface of the vehicle's dashboard and located inside the windshield. The PHUD includes a housing, a display screen, and a light-emitting module. Both the light-emitting module and the display screen are housed inside the housing. The housing has a light-emitting port, and the display screen is located near the light-emitting port. The light-emitting module supplies light to the display screen, illuminating and displaying the image on the screen, which is then output through the light-emitting port. However, in related technologies, the display screen has a large divergence angle, resulting in less light entering the user's eyes and low image brightness, making it difficult for users to view the image in bright sunlight.

[0071] Figure 1 This is a schematic diagram of an application scenario of the projection device provided in the embodiments of this application.

[0072] Therefore, in the embodiments of this application, see Figure 1 The projection device 100 includes an image generating device 150 and a diffusion element 140. The image generating device 150 generates image light including image information, which forms a real image at the diffusion element 140. The diffusion element 140 diffuses the image light from the image generating device 150, thus expanding the eyebox and allowing light from more angles to be seen by the user.

[0073] In some embodiments, such as Figure 1 As shown, the vehicle also includes a windshield and a dashboard. The image generating device 150 is fixedly connected to the surface of the dashboard and located inside the windshield, and the diffuser element 140 is disposed on the windshield. When the projection device 100 is working, the image light generated by the image generating device 150 is projected onto the diffuser element 140, and the diffuser element 140 reflects the diffused image light to the user's eye, allowing the user to see the image.

[0074] In this way, the projection device 100 can form a panoramic head-up display device, which can project vehicle information (such as speed, navigation, etc.) onto the windshield in a panoramic driving view, so that the driver can obtain the projected information without looking down, thereby improving driving safety and interactive experience.

[0075] It should be noted that when the projection device 100 is applied to a vehicle, the vehicle may include one or more projection devices.

[0076] In some embodiments, when the vehicle includes a projection device 100, the projection device 100 serves as a head-up display or an in-vehicle display. Alternatively, in some embodiments, the vehicle includes multiple projection devices 100, which include a first projection device and a second projection device. The first projection device serves as a head-up display, and the second projection device serves as an in-vehicle display. The number of second projection devices can be one or more.

[0077] The diffuser element 140 of the vehicle display device can be installed on the rear windshield or door glass of the vehicle, or the diffuser element 140 of the vehicle display device can be a projection screen with a diffusion function.

[0078] In some possible implementations, the diffuser element 140 is disposed inside the windshield, in which case the windshield can protect the diffuser element 140 from damage.

[0079] For example, the windshield may include an inner glass layer and an outer glass layer, with a diffuser element 140 disposed between the inner and outer glass layers, and the windshield and the diffuser element 140 forming a sandwich structure.

[0080] In some possible implementations, the diffuser element 140 is disposed on the surface of the windshield, which reduces the difficulty of the windshield supporting the diffuser element 140.

[0081] In some embodiments, such as Figure 1 As shown, the diffusion element 140 is a reflective diffusion element, which is used to diffuse the image light from the image generating device 150 and reflect the diffused image light to the human eye.

[0082] In some embodiments, the diffusion element 140 is a transmissive diffusion element, which is used to diffuse the image light from the image generating device 150 and transmit the diffused image light to the human eye.

[0083] In some embodiments, the diffusion element 140 may be a diffusion screen, which may also be called a diffusion sheet or diffusion plate.

[0084] For example, the surface of the diffuser screen is provided with a microstructure array, which includes multiple microstructures arranged in an array to achieve light diffusion.

[0085] In some embodiments, the diffusion element 140 can be a holographic diffusion element, which is a holographic optical element (HOE) made using holographic technology. The diffusion function of the HOE is achieved through a holographic exposure process, mainly by using the photochemical reaction of photosensitive materials to record interference patterns and form specific micro-nano structures, thereby controlling the scattering and diffraction of incident light. In this way, the holographic diffusion element can produce a diffusion effect on imaging light at a specific incident angle while maintaining high transmittance for ambient light, allowing the driver to see the image while clearly viewing the real environment.

[0086] In some embodiments, the diffusion element 140 may also be a particle diffusion element generated by a particle diffusion function. A particle diffusion element is an optical thin film that achieves light homogenization by incorporating scattering particles.

[0087] Figure 2 for Figure 1 A schematic diagram of the projection device.

[0088] See Figure 2 The image generating apparatus 150 includes an image source 110, a projection lens 120, and a curved reflector 130. The image source 110 is located on the light-inlet side of the projection lens 120, the curved reflector 130 is located on the light-outlet side of the projection lens 120, and the diffuser element 140 is located along the optical axis of the projection lens 120 (e.g., along the light-emitting side of the projection lens 120). Figure 2 The diffuser element 140 (located in the X direction) is positioned between the image source 110 and the curved reflector 130. In a plane perpendicular to the optical axis, the orthographic projection of the diffuser element 140 does not coincide with the orthographic projection of the projection lens 120. The projection lens 120 projects the image light generated by the image source 110 onto the curved reflector 130. The curved reflector 130 reflects the image light emitted from the projection lens 120 to the diffuser element 140, which diffuses the image light from the curved reflector 130.

[0089] In this embodiment, the curved reflector 130 converges the image light emitted from the projection lens 120, increasing the image light received by the diffuser 140. This increases the image light projected to the human eye by the diffuser 140, thereby enhancing the image light received by the human eye and ensuring that the user can see the image even in strong light. Furthermore, the diffuser 140 is positioned along the optical axis between the image source 110 and the curved reflector 130, reducing the size of the projection device 100 along the optical axis and contributing to a smaller overall size. Moreover, the cooperation of the projection lens 120, the curved reflector 130, and the diffuser 140 achieves short-distance projection (ultra-short-throw projection) while maintaining high image quality and low distortion.

[0090] In some embodiments, the curved reflector 130 may also be referred to as a curved reflector bowl.

[0091] In this embodiment, the non-overlapping orthographic projections of the projection lens 120 and the diffusion element 140 in a plane perpendicular to the optical axis can be understood as the diffusion element 140 not blocking the projection lens 120 along the optical axis.

[0092] In some embodiments, such as Figure 2 As shown, the diffuser element 140 and the projection lens 120 are in a direction perpendicular to the optical axis of the projection lens 120 (e.g., Figure 2 (Z-direction) Spacing settings.

[0093] Of course, in some embodiments, the distance between the diffuser element 140 and the projection lens 120 in the direction perpendicular to the optical axis can also be zero.

[0094] In some possible implementations, such as Figure 2 As shown, the projection lens 120 includes a projection lens along the optical axis direction (e.g., Figure 2 A first lens group 121, an aperture 123, and a second lens group 122 are arranged in the X-direction. The first lens group 121 is close to the curved mirror 130, and the second lens group 122 is close to the image source 110. Both the first lens group 121 and the second lens group 122 include at least four lenses arranged along the optical axis of the projection lens 120. In this way, while achieving a small-volume design for the projection device 100, the image quality can be further improved and distortion reduced.

[0095] In some embodiments, the first lens group 121 has six lenses and the second lens group 122 has six lenses. This ensures that the projection device 100 remains compact while further improving image quality and display performance.

[0096] Of course, the number of lenses in the first lens group 121 can be less than or more than six, for example, the number of lenses in the first lens group 121 can also be four or seven.

[0097] Of course, the number of lenses in the second lens group 122 can be less than or more than six, for example, the number of lenses in the second lens group 122 can also be four or seven.

[0098] In some possible implementations, such as Figure 2 As shown, the image source 110 includes a light source 111 and a modulation device 112. The modulation device 112 is used to modulate the light emitted by the light source 111 to obtain image light including image information.

[0099] The modulation device 112 includes, but is not limited to, liquid crystal display (LCD), liquid crystal on silicon (LCOS), digital micro-mirror device (DMD), and thin film transistor (TFT).

[0100] Of course, in addition to the light source 111 and the modulation device 112, the image source 110 may also include other devices, such as in some embodiments. Figure 2 As shown, the image source 110 may also include a cover glass 113 (CG), which is located on the light-emitting side of the modulator 112 and protects the modulator 112. The number of cover glasses 113 can be one or more, and there is no limitation here.

[0101] In some possible implementations, such as Figure 2 As shown, the diffusion element 140 is disposed between the light-inlet side and the light-outlet side of the projection lens 120 along the optical axis.

[0102] This avoids the distance between the vertex of the curved reflector 130 and the diffusion element 140 along the optical axis being too large or too small, effectively balancing the size of the diffusion element 140 and the display area in the direction perpendicular to the optical axis, and ensuring imaging quality and miniaturization of the projection device 100.

[0103] In some embodiments, such as Figure 2 As shown, along the optical axis (e.g.) Figure 2 In the X direction, the diffuser element 140 is located between the light-inlet side and the light-outlet side of the first mirror group 121. In this way, while ensuring the display area, the volume of the projection device 100 is further reduced and the image quality is ensured.

[0104] In some possible implementations, the projection lens 120 satisfies the relationship: -3 ≤ EFL1 / L ≤ 3. Where EFL1 is the focal length of the first lens group 121, such as... Figure 2 As shown, L is the vertex of the curved mirror 130 along the optical axis (e.g., Figure 2 The distance from the diffuser element 140 in the X direction.

[0105] In this way, the distance between the vertex of the curved mirror 130 and the diffusion element 140 can be effectively balanced with the imaging quality, so that the distance between the vertex of the curved mirror 130 and the diffusion element 140 is smaller, which helps to further reduce the size of the projection device 100.

[0106] In this embodiment of the application, the vertex of the curved mirror 130 refers to the geometric center point of the curved mirror 130.

[0107] In some embodiments, the projection lens 120 satisfies the relationship: -1.3 ≤ EFL1 / L ≤ 0.9. This further reduces the size of the projection device 100 and ensures that the image quality meets the requirements.

[0108] The specific ratio of EFL1 / L can be 0.85, 0.8128, 0.8, 0.7, 0.5, 0.3, 0.1, -1.125, -1.1, -1.0, -1.2, -0.9, -0.8, etc.

[0109] Of course, the specific ratio of EFL1 / L can also be set to other values ​​according to requirements. For example, the projection lens 120 can satisfy the relationship: -0.1≤EFL1 / L≤-0.05. Among them, the specific ratio of EFL1 / L can be -0.06, -0.065, -0.067, -0.08, -0.09, etc.

[0110] It should be noted that, in addition to being in the range of -3 to 3, the specific ratio of EFL1 / L in some embodiments may also be less than -3 or greater than 3.

[0111] In some possible implementations, the projection lens 120 satisfies the relationship: -200mm ≤ EFL1 ≤ 200mm. This allows the optical path of the first lens group 121 to be designed as a short optical path, which helps to reduce the size of the projection device 100 and ensures image quality.

[0112] The focal lengths of the first lens group 121 can be 20mm, 50mm, 60mm, 81.28mm, 90mm, 100mm, 150mm, 180mm, -150mm, -140mm, -135mm, -134.97mm, -100mm, -90mm, -80mm, -10mm, etc.

[0113] In some possible implementations, the projection lens 120 satisfies the relationship: -0.5 ≤ EFL2 / L ≤ -0.1, where EFL2 is the focal length of the second lens group 122. This ensures image quality while reducing the distance between the vertex of the curved reflector 130 and the diffuser element 140, further reducing the size of the projection device 100.

[0114] The specific ratio of EFL2 / L can be -0.5, -0.4, -0.398, -0.2, -0.22, -0.2516, -0.05, 0.01, 0.05, 0.1, etc.

[0115] Of course, in addition to being in the range of -0.5 to -0.1, in some embodiments, the specific ratio of EFL2 / L can also be less than -0.5 or greater than -0.1.

[0116] In some possible implementations, the projection lens 120 satisfies the relationship: -35mm ≤ EFL2 ≤ -10mm. This allows the optical path of the second lens group 122 to be designed as a short optical path, which helps to reduce the size of the projection device 100 and ensures image quality.

[0117] The specific values ​​for EFL2 can be -35mm, -30mm, -27mm, -36.45mm, -25mm, -25.16mm, -20mm, -15mm, etc.

[0118] In some possible implementations, the projection device 100 satisfies the relationship: 100mm≤L≤120mm. This allows for a small distance between the apex of the diffuser element 140 and the curved reflector 130, while effectively balancing the relationship between the size of the diffuser element 140, the imaging quality, and the projection device 100, thus achieving high imaging quality, a small-volume design for the projection device 100, and a relatively large size for the diffuser element 140.

[0119] The specific value of L can be 100mm, 105mm, 110mm, 111.25mm, 120mm, etc.

[0120] It should be noted that, in addition to being between 100mm and 120mm, in some embodiments, the specific value of L can be less than 100mm or greater than 120mm.

[0121] In some possible implementations, the projection device 100 satisfies the relationship: 123mm ≤ IMH1 ≤ 369mm. Where, for example... Figure 2As shown, IMH1 is the top of the diffuser element 140 and the optical axis of the projection lens 120 (e.g., Figure 2 In the direction perpendicular to the optical axis (e.g., P) Figure 2 The distance in the Z direction.

[0122] This allows the projection device 100 to be designed with a small size in the direction perpendicular to the optical axis, which helps to reduce the volume of the projection device 100 and reduce the space required to arrange the projection device 100.

[0123] The specific values ​​for IMH1 can be 125mm, 150mm, 180mm, 190mm, 200mm, 210mm, 240mm, 246mm, 250mm, 280mm, 300mm, 350mm, etc.

[0124] In this embodiment, the top of the diffusion element 140 refers to the direction of the diffusion element 140 perpendicular to the optical axis (e.g., Figure 2 The optical axis (e.g., in the Z-direction) is 120 degrees away from the projection lens. Figure 2 The farthest end of the diffuser element 140. Or, the top of the diffuser element 140 can also be understood as the end of the diffuser element 140 that is far away from the projection lens 120 in a direction perpendicular to the optical axis.

[0125] In some possible implementations, the projection device 100 satisfies the relationship: 33mm ≤ IMH2 ≤ 99mm. Where, for example... Figure 2 As shown, IMH2 is the distance between the bottom of the diffusion element 140 and the optical axis of the projection lens 120 in a direction perpendicular to the optical axis.

[0126] This allows for a small-pitch design between the diffuser element 140 and the projection lens 120 in the direction perpendicular to the optical axis, which further reduces the size of the projection device 100 in the direction perpendicular to the optical axis, thereby further reducing the volume of the projection device 100.

[0127] The specific values ​​for IMH2 can be 33mm, 35mm, 40mm, 50mm, 60mm, 66mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, etc.

[0128] In this embodiment, the bottom end of the diffusion element 140 refers to the direction of the diffusion element 140 perpendicular to the optical axis (e.g., Figure 2 The optical axis (e.g., in the Z-direction) is 120 degrees away from the projection lens. Figure 2 The end closest to the projection lens 120 (P). Or, the bottom end of the diffusion element 140 can also be understood as the end of the diffusion element 140 that is close to the projection lens 120 in a direction perpendicular to the optical axis.

[0129] The specific structure of the projection device 100 provided in this application will be described below with reference to specific embodiments.

[0130] Implementation 1

[0131] Figure 3 This is a schematic diagram of the structure of a projection device provided in Embodiment 1 of this application.

[0132] See Figure 3 The projection device 100 includes an image source 110, a projection lens 120, a curved reflector 130, and a diffusion element 140. The image source 110 is located on the light-inlet side of the projection lens 120, and includes a light source 111. Figure 3 (Not shown in the image), cover glass 113 and modulation device 112, the cover glass 113 is located between the light source 111 and the modulation device 112 along the optical axis of the projection lens 120, and the modulation device 112 is close to the projection lens 120. A curved reflector 130 is disposed on the light-emitting side of the projection lens 120, and a diffuser 140 is disposed between the light-input side and the light-output side of the projection lens 120 along the optical axis of the projection lens 120. The diffuser 140 is positioned in a direction perpendicular to the optical axis (e.g., ...). Figure 3 The distance between the projection lens and the center Z direction is 120 degrees.

[0133] like Figure 3 As shown, the projection lens 120 includes a first lens group 121, an aperture 123, and a second lens group 122 arranged sequentially along the optical axis of the projection lens 120. The first lens group 121 is close to the curved reflector 130, and the second lens group 122 is close to the cover glass 113.

[0134] like Figure 3 As shown, the first lens group 121 includes a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, a fifth lens G5 and a sixth lens G6 arranged sequentially along the optical axis of the projection lens 120. The first lens G1 is closest to the curved mirror 130 and the sixth lens G6 is closest to the aperture stop 123.

[0135] The first lens G1 has negative optical power, and its focal length f1 = -31.94 mm. The second lens G2 has negative optical power, and its focal length f2 = -61.61 mm. The third lens G3 has positive optical power, and its focal length f3 = 20.44 mm. The fourth lens G4 has positive optical power, and its focal length f4 = 30.62 mm. The fifth lens G5 has negative optical power, and its focal length f5 = -28.29 mm. The sixth lens G6 has negative optical power, and its focal length f6 = -54.78 mm.

[0136] like Figure 3 As shown, the second lens group 122 includes a seventh lens G7, an eighth lens G8, a ninth lens G9, a tenth lens G10, an eleventh lens G11, and a twelfth lens G12 arranged sequentially along the optical axis of the projection lens 120. The seventh lens G7 is closest to the aperture stop 123, and the twelfth lens G12 is closest to the cover glass 113.

[0137] The seventh lens G7 has negative optical power and a focal length f7 = -17.92 mm. The eighth lens G8 has positive optical power and a focal length f8 = 10.40 mm. The ninth lens G9 has negative optical power and a focal length f9 = -15.35 mm. The tenth lens G10 has positive optical power and a focal length f10 = 8.45 mm. The eleventh lens G11 has negative optical power and a focal length f11 = -15.88 mm. The twelfth lens G12 has negative optical power and a focal length f12 = -25.33 mm.

[0138] In some embodiments, any one of the lenses in the projection lens 120 is made of optical glass or plastic.

[0139] In some embodiments, the surface profile of any one of the lenses in the projection lens 120 is spherical or aspherical; for example, the surface profile of any one of the lenses is spherical.

[0140] The focal length (EFL1) of the first lens group 121 is 81.28mm, and the focal length (EFL2) of the second lens group 122 is -25.16mm.

[0141] The curved reflector 130 has a radius of curvature of 35.06 mm. The distance between the vertex of the curved reflector 130 and the diffuser 140 along the optical axis of the projection lens 120 is L = 100 mm. EFL1 / L = 0.8128 and EFL2 / L = -0.2516.

[0142] The distance between the top of the diffuser element 140 and the optical axis of the projection lens 120 in the direction perpendicular to the optical axis is IMH1 = 246 mm, and the distance between the bottom of the diffuser element 140 and the optical axis of the projection lens 120 in the direction perpendicular to the optical axis is IMH2 = 66 mm.

[0143] Table 1 shows the optical parameters of each optical element of the projection device 100 in Embodiment 1 of this application.

[0144]

[0145]

[0146] Wherein, OBJ is the diffuser element 140, S1 is the curved mirror 130, S2 is the image-side surface of the first lens G1, S3 is the object-side surface of the first lens G1, S4 is the image-side surface of the second lens G2, S5 is the object-side surface of the second lens G2, S6 is the image-side surface of the third lens G3, S7 is the object-side surface of the third lens G3, S8 is the image-side surface of the fourth lens G4, S9 is the object-side surface of the fourth lens G4, S10 is the image-side surface of the fifth lens G5, S11 is the object-side surface of the fifth lens G5, S12 is the image-side surface of the sixth lens G6, S13 is the image-side surface of the sixth lens G6, Stop is the aperture stop 123, S14 is the image-side surface of the seventh lens G7, and S15 is... The object-side surface of the seventh lens G7, S16 is the image-side surface of the eighth lens G8, S17 is the object-side surface of the eighth lens G8, S18 is the image-side surface of the ninth lens G9, S19 is the object-side surface of the ninth lens G9, S20 is the image-side surface of the tenth lens G10, S21 is the object-side surface of the tenth lens G10, S22 is the image-side surface of the eleventh lens G11, S23 is the object-side surface of the eleventh lens G11, S24 is the image-side surface of the twelfth lens G12, S25 is the object-side surface of the twelfth lens G12, S26 is the image-side surface of the cover glass 113, S27 is the object-side surface of the cover glass 113, S28 to S30 are the modulation device 112, and Image is the imaging surface.

[0147] Where R is the radius of curvature of the optical element (such as a lens or cover glass 113) at the corresponding position on the optical axis, TH is the surface thickness of the optical element along the optical axis, Nd is the refractive index of each optical element when d-line is incident on it, and Vd is the Abbe number of the optical element.

[0148] Table 2 shows Figure 3 The optical parameters of the projection lens 120 in the middle.

[0149] f1(mm) -31.94 f7 (mm) -17.92 f2 (mm) -61.61 f8(mm) 10.40 f3 (mm) 20.44 f9(mm) -15.35 f4 (mm) 30.62 f10(mm)) 8.45 f5 (mm) -28.29 f11(mm) -15.88 f6 (mm) -54.78 f12 (mm) -25.33 EFL1 (mm) 81.28 EFL2 (mm) -25.16

[0150] Wherein, f1 is the focal length of the first lens G1. f2 is the focal length of the second lens G2. f3 is the focal length of the third lens G3. f4 is the focal length of the fourth lens G4. f5 is the focal length of the fifth lens G5. f6 is the focal length of the sixth lens G6. f7 is the focal length of the seventh lens G7. f8 is the focal length of the eighth lens G8. f9 is the focal length of the ninth lens G9. f10 is the focal length of the tenth lens G10. f11 is the focal length of the eleventh lens G11. f12 is the focal length of the twelfth lens G12. EFL1 is the focal length of the first lens group 121. EFL2 is the focal length of the second lens group 122.

[0151] Figure 4 for Figure 3 The spherical chromatic aberration diagram of the projection lens. Figure 4In the diagram, the vertical axis represents the normalized pupil coordinates, and the horizontal axis represents the aberrations along the axial direction, with units of millimeters. Figure 4 In the diagram, the three curves correspond to the axial aberration curves of light with wavelengths of 625nm, 550nm, and 455nm after passing through the projection lens 120 of Embodiment 1 of this application. From... Figure 4 As can be seen, in Embodiment 1 of this application, the axial aberration is controlled within a very small range, resulting in good correction.

[0152] Figure 5 for Figure 3 The image scattering curve of the projection lens in the image. Figure 6 for Figure 3 The distortion diagram of the projection lens in the image. Figure 5 In the diagram, S represents the field curvature of light with a wavelength of 550 nm in the meridional image plane, and T represents the field curvature of light with a wavelength of 550 nm in the sagittal image plane. Figure 6 In the diagram, the solid line represents the distortion value of light with a center wavelength of 550nm passing through the projection lens 120 of Embodiment 1 of this application. (Combined with...) Figure 5 and Figure 6 It is understood that the projection lens 120 provided in Embodiment 1 of this application controls field curvature and distortion within the corresponding range, which can meet the usage requirements.

[0153] Implementation 2

[0154] Figure 7 This is a schematic diagram of the structure of a projection device provided in Embodiment 2 of this application.

[0155] See Figure 7 The projection device 100 includes an image source 110, a projection lens 120, a curved reflector 130, and a diffusion element 140. The image source 110 is located on the light-inlet side of the projection lens 120, and includes a light source 111. Figure 7 (not shown in the image), cover glass 113 and modulation device 112, cover glass 113 is along the optical axis of projection lens 120 (e.g., Figure 7 The light source 111 and the modulator 112 are located in the X direction, with the modulator 112 close to the projection lens 120. A curved reflector 130 is positioned on the light-emitting side of the projection lens 120. A diffuser 140 is positioned between the light-inlet side and the light-emitting side of the projection lens 120 along the optical axis of the projection lens 120. The diffuser 140 is positioned in a direction perpendicular to the optical axis (e.g., ...). Figure 7 The distance between the projection lens and the center Z direction is 120 degrees.

[0156] like Figure 7As shown, the projection lens 120 includes a first lens group 121, an aperture 123, and a second lens group 122 arranged sequentially along the optical axis of the projection lens 120. The first lens group 121 is close to the curved reflector 130, and the second lens group 122 is close to the cover glass 113.

[0157] like Figure 7 As shown, the first lens group 121 includes a first lens G1, a second lens G2, a third lens G3, a fourth lens G4, a fifth lens G5 and a sixth lens G6 arranged sequentially along the optical axis of the projection lens 120. The first lens G1 is closest to the curved mirror 130 and the sixth lens G6 is closest to the aperture stop 123.

[0158] The first lens G1 has negative optical power and a focal length f1 = -24.59 mm. The second lens G2 has positive optical power and a focal length f2 = 34.29 mm. The third lens G3 has positive optical power and a focal length f3 = 25.98 mm. The fourth lens G4 has positive optical power and a focal length f4 = 19.24 mm. The fifth lens G5 has negative optical power and a focal length f5 = -19.73 mm. The sixth lens G6 has negative optical power and a focal length f6 = -41.26 mm.

[0159] like Figure 7 As shown, the second lens group 122 includes a seventh lens G7, an eighth lens G8, a ninth lens G9, a tenth lens G10, an eleventh lens G11, and a twelfth lens G12 arranged sequentially along the optical axis of the projection lens 120. The seventh lens G7 is closest to the aperture stop 123, and the twelfth lens G12 is closest to the cover glass 113.

[0160] The seventh lens G7 has negative optical power and a focal length f7 = -18.06 mm. The eighth lens G8 has positive optical power and a focal length f8 = 9.26 mm. The ninth lens G9 has negative optical power and a focal length f9 = -15.72 mm. The tenth lens G10 has positive optical power and a focal length f10 = 9.44 mm. The eleventh lens G11 has negative optical power and a focal length f11 = -16.31 mm. The twelfth lens G12 has negative optical power and a focal length f12 = -28.73 mm.

[0161] In some embodiments, any one of the lenses in the projection lens 120 is made of optical glass or plastic.

[0162] In some embodiments, the surface profile of any one of the lenses in the projection lens 120 is spherical or aspherical; for example, the surface profile of any one of the lenses is spherical.

[0163] The focal length (EFL1) of the first lens group 121 is -134.97mm, and the focal length (EFL2) of the second lens group 122 is -26.45mm.

[0164] The curved reflector 130 has a radius of curvature of 34.13 mm. The distance between the vertex of the curved reflector 130 and the diffuser 140 along the optical axis of the projection lens 120 is L = 120 mm. EFL1 / L = -1.125 and EFL2 / L = -0.22.

[0165] The distance between the top of the diffuser element 140 and the optical axis of the projection lens 120 in the direction perpendicular to the optical axis is IMH1 = 246 mm, and the distance between the bottom of the diffuser element 140 and the optical axis of the projection lens 120 in the direction perpendicular to the optical axis is IMH2 = 66 mm.

[0166] Table 3 shows the optical parameters of each optical element of the projection device 100 in Embodiment 2 of this application.

[0167]

[0168]

[0169] Wherein, OBJ is the diffuser element 140, S1 is the curved mirror 130, S2 is the image-side surface of the first lens G1, S3 is the object-side surface of the first lens G1, S4 is the image-side surface of the second lens G2, S5 is the object-side surface of the second lens G2, S6 is the image-side surface of the third lens G3, S7 is the object-side surface of the third lens G3, S8 is the image-side surface of the fourth lens G4, S9 is the object-side surface of the fourth lens G4, S10 is the image-side surface of the fifth lens G5, S11 is the object-side surface of the fifth lens G5, S12 is the image-side surface of the sixth lens G6, S13 is the image-side surface of the sixth lens G6, Stop is the aperture stop 123, S14 is the image-side surface of the seventh lens G7, and S15 is... The object-side surface of the seventh lens G7, S16 is the image-side surface of the eighth lens G8, S17 is the object-side surface of the eighth lens G8, S18 is the image-side surface of the ninth lens G9, S19 is the object-side surface of the ninth lens G9, S20 is the image-side surface of the tenth lens G10, S21 is the object-side surface of the tenth lens G10, S22 is the image-side surface of the eleventh lens G11, S23 is the object-side surface of the eleventh lens G11, S24 is the image-side surface of the twelfth lens G12, S25 is the object-side surface of the twelfth lens G12, S26 is the image-side surface of the cover glass 113, S27 is the object-side surface of the cover glass 113, S28 to S30 are the modulation device 112, and Image is the imaging surface.

[0170] Where R is the radius of curvature of the optical element (such as a lens or cover glass 113) at the corresponding position on the optical axis, TH is the surface thickness of the optical element along the optical axis, Nd is the refractive index of each optical element when d-line is incident on it, and Vd is the Abbe number of the optical element.

[0171] Table 4 shows Figure 7 The optical parameters of the projection lens 120 in the middle.

[0172] f1(mm) -24.59 f7 (mm) -18.06 f2 (mm) 34.29 f8(mm) 9.26 f3 (mm) 25.98 f9(mm) -15.72 f4 (mm) 19.24 f10(mm)) 9.44 f5 (mm) -19.73 f11(mm) -16.31 f6 (mm) -41.26 f12 (mm) -28.73 EFL1 (mm) -134.97 EFL2 (mm) -25.45

[0173] Wherein, f1 is the focal length of the first lens G1. f2 is the focal length of the second lens G2. f3 is the focal length of the third lens G3. f4 is the focal length of the fourth lens G4. f5 is the focal length of the fifth lens G5. f6 is the focal length of the sixth lens G6. f7 is the focal length of the seventh lens G7. f8 is the focal length of the eighth lens G8. f9 is the focal length of the ninth lens G9. f10 is the focal length of the tenth lens G10. f11 is the focal length of the eleventh lens G11. f12 is the focal length of the twelfth lens G12. EFL1 is the focal length of the first lens group 121. EFL2 is the focal length of the second lens group 122.

[0174] Figure 8 for Figure 7 The spherical chromatic aberration diagram of the projection lens. Figure 8 In the diagram, the vertical axis represents the normalized pupil coordinates, and the horizontal axis represents the aberrations along the axial direction, with units of millimeters. Figure 8 In the diagram, the three curves correspond to the axial aberration curves of light with wavelengths of 625nm, 550nm, and 455nm after passing through the projection lens 120 of Embodiment 2 of this application. Figure 8 As can be seen, in Embodiment 2 of this application, the axial aberration is controlled within a very small range, resulting in good correction.

[0175] Figure 9 for Figure 7 The image scattering curve of the projection lens in the image. Figure 10 for Figure 7 The distortion diagram of the projection lens in the image. Figure 9 In the diagram, S represents the field curvature of light with a wavelength of 550 nm in the meridional image plane, and T represents the field curvature of light with a wavelength of 550 nm in the sagittal image plane. Figure 10 In the diagram, the solid line represents the distortion value of light with a center wavelength of 550nm passing through the projection lens 120 of Embodiment 2 of this application. (Combined with...) Figure 9 and Figure 10 It can be seen that the projection lens 120 provided in Embodiment 2 of this application controls the field curvature and distortion within the corresponding range, which can meet the usage requirements.

[0176] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances. The terms "first," "second," "third," "fourth," etc. (if present) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0177] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the embodiments of this application, and are not intended to limit them. Although the embodiments of this application have been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A projection device (100), characterized in that, It includes an image source (110), a projection lens (120), a curved reflector (130), and a diffusion element (140); The image source (110) is located on the light-inlet side of the projection lens (120), the curved reflector (130) is located on the light-outlet side of the projection lens (120), and the diffuser (140) is disposed between the image source (110) and the curved reflector (130) along the optical axis of the projection lens (120). In a plane perpendicular to the optical axis, the orthographic projection of the diffuser (140) does not coincide with the orthographic projection of the projection lens (120). The projection lens (120) is used to project the image light generated by the image source (110) onto the curved mirror (130), the curved mirror (130) reflects the image light emitted from the projection lens (120) onto the diffusion element (140), and the diffusion element (140) diffuses the image light from the curved mirror (130).

2. The projection device (100) according to claim 1, characterized in that, The diffusion element (140) is disposed between the light-inlet side and the light-outlet side of the projection lens (120) along the optical axis.

3. The projection device (100) according to claim 1, characterized in that, The projection lens (120) includes a first lens group (121), an aperture (123), and a second lens group (122) arranged along the optical axis of the projection lens (120). The first lens group (121) is close to the curved mirror (130), and the second lens group (122) is close to the image source (110). Both the first lens group (121) and the second lens group (122) include at least four lenses arranged along the optical axis of the projection lens (120).

4. The projection device (100) according to claim 3, characterized in that, The first lens group (121) and the second lens group (122) both have six lenses.

5. The projection device (100) according to claim 3 or 4, characterized in that, The projection lens (120) satisfies the following relationship: -3≤EFL1 / L≤3; where EFL1 is the focal length of the first lens group (121) and L is the distance from the vertex of the curved mirror (130) along the optical axis to the diffuser element (140).

6. The projection device (100) according to claim 5, characterized in that, The projection lens (120) satisfies the following relationship: -1.3≤EFL1 / L≤0.

9.

7. The projection device (100) according to claim 3 or 4, characterized in that, The projection lens (120) satisfies the following relationship: -200mm≤EFL1≤200mm.

8. The projection device (100) according to claim 3 or 4, characterized in that, The projection lens (120) satisfies the following relationship: -0.5≤EFL2 / L≤-0.1; where EFL2 is the focal length of the second lens group (122).

9. The projection device (100) according to claim 3 or 4, characterized in that, The projection lens (120) satisfies the following relationship: -35mm≤EFL2≤-10mm.

10. The projection device (100) according to any one of claims 1-4, characterized in that, The projection device (100) satisfies the following relationship: 100mm≤L≤120mm.

11. The projection device (100) according to any one of claims 1-4, characterized in that, The projection device (100) satisfies the following relationship: 123mm≤IMH1≤369mm; wherein, IMH1 is the distance between the top of the diffusion element (140) and the optical axis of the projection lens (120) in a direction perpendicular to the optical axis.

12. The projection device (100) according to any one of claims 1-4, characterized in that, The projection device (100) satisfies the following relationship: 33mm≤IMH2≤99mm; wherein, IMH2 is the distance between the bottom end of the diffusion element (140) and the optical axis of the projection lens (120) in a direction perpendicular to the optical axis.

13. The projection device (100) according to any one of claims 1-4, characterized in that, The image source (110) includes: Light source (111); A modulation device (112) is used to modulate the light emitted by the light source (111) to obtain the image light including image information.

14. The projection device (100) according to claim 13, characterized in that, The modulation device (112) is any one of a liquid crystal display, a silicon-based liquid crystal, a digital micromirror device, or a thin-film transistor.

15. A display device, characterized in that, Includes a processor and a projection device (100) as described in any one of claims 1-14, the processor being configured to send image data to an image source (110) of the projection device (100) to cause the image source (110) to generate the image light.

16. A means of transportation, characterized in that, Includes the projection device (100) as described in any one of claims 1-14.

17. The means of transport according to claim 16, characterized in that, The vehicle also includes a windshield and a dashboard; The projection device (100) includes an image generating device (150) and a diffusion element (140). The image generating device (150) includes an image source (110), a projection lens (120), and a curved reflector (130). The image generating device (150) is fixedly connected to the surface of the dashboard, and the diffusion element (140) is disposed on the windshield.

18. The means of transport according to claim 17, characterized in that, The diffuser element (140) is disposed inside the windshield, or the diffuser element (140) is disposed on the surface of the windshield.

Images