Split-screen projection device

Abstract

Provided in the present invention is a split-screen projection device. The split-screen projection device comprises: a projection lens module which sequentially comprises, from a first side to a second side, a plurality of lenses having diopters and an imaging light valve; and a light-splitting module located on the first side of the projection lens module and disposed on an optical axis of the projection lens module, wherein the light-splitting module has a plurality of reflecting surfaces, the plurality of reflecting surfaces reflect light in different directions, and the plurality of reflecting surfaces are configured to receive projection light of the projection lens module and reflect the received projection light to different positions to form a plurality of projection images. The present invention solves the problems in the prior art of split-screen projection devices having a complex structure and a poor imaging quality.

Description

Split-screen projection device TECHNICAL FIELD

[0001] The present application relates to the technical field of optical projection equipment, in particular to a split-screen projection device. BACKGROUND

[0002] With the development of intelligent projection technology, the new intelligent car is usually equipped with an intelligent display device. For example, the projection device installed in the car can enable the user to realize audio-visual interaction and increase the atmosphere of the car's intelligent warehouse, and achieve a new human-computer interaction experience.

[0003] The projection direction area of the conventional projection device of the vehicle is single. In order to realize multi-screen projection display in the projection area of the vehicle, multiple projectors are generally required to achieve this requirement, which has a relatively high cost and an increase in volume that is not conducive to assembly in the limited space of the vehicle. The existing split-screen projection device is provided by a light splitting device to achieve split-screen, but the existing light splitting device has a complex structure and specific requirements for signal source information technology. The light signal of the image light valve needs to be polarized light. Such a chip has poor heat dissipation, and the polarization light imaging is easy to produce speckle and affect the projection quality. In addition, the details of how to plan the parameters of the light splitting device and the lens are not disclosed in the prior art, making it difficult to match the light splitting device and the lens, and making it difficult to apply the scheme to actual products.

[0004] That is, the split-screen projection device in the prior art has the problems of complex structure and poor imaging quality. SUMMARY

[0005] The main purpose of the present application is to provide a split-screen projection device to solve the problem of complex structure and poor imaging quality of the split-screen projection device in the prior art.

[0006] In order to achieve the above purpose, the present application provides a split-screen projection device, comprising: a projection lens module, the projection lens module sequentially comprises a plurality of lenses with refractive power and an image light valve from the first side to the second side; a light splitting module, the light splitting module is located on the first side of the projection lens module and on the optical axis of the projection lens module, the light splitting module has a plurality of reflecting surfaces, the reflecting directions of the plurality of reflecting surfaces are different, and the plurality of reflecting surfaces are used to receive all the projection light of the projection lens module and reflect to different positions to form a plurality of projection pictures.

[0007] Further, the plurality of reflecting surfaces comprises a first reflecting surface and a second reflecting surface, the first reflecting surface is arranged at an angle with the optical axis, the second reflecting surface is arranged at an angle with the optical axis, and the included angle between the first reflecting surface and the optical axis is the same as or different from the included angle between the second reflecting surface and the optical axis.

[0008] Further, the central axis of the light splitting module coincides with the optical axis of the projection lens module, and the plurality of reflecting surfaces comprises a first reflecting surface and a second reflecting surface, and the first reflecting surface and the second reflecting surface are arranged in axial symmetry with the optical axis as the axis of symmetry.

[0009] Further, a distance h from the vertex of the light splitting module on the central axis to the light valve on the optical axis satisfies: 50mm≤h≤200mm; and / or, a distance h from the vertex of the light splitting module on the central axis to the projection target surface on the optical axis and an intercept H between the vertex of the light splitting module on the central axis and the projection target surface satisfy: 0.8≤H / h≤2.

[0010] Further, an angle a between the reflecting surface and the optical axis of the projection lens module satisfies: 0.6≤tan a≤3.5.

[0011] Further, an angle a between the reflecting surface and the optical axis and a maximum field of view angle fov of the projection lens module satisfy: 0.7≤fov / a≤1.3.

[0012] Further, at least one of the plurality of lenses with refractive power is a cylindrical lens or a free-form surface lens, and the cylindrical lens or the free-form surface lens has different focal lengths and magnifications in the x direction and the y direction.

[0013] Further, a focal length EFL_x of the projection lens module in the x direction and a focal length EFL_y of the projection lens module in the y direction satisfy: 1.1≤EFL_x / EFL_y≤1.8.

[0014] Further, a magnification β2 of the projection lens module in the x direction and a magnification β1 of the projection lens module in the y direction satisfy: 0.5≤β1 / β2≤1.0.

[0015] Further, the plurality of lenses comprises a first lens with negative refractive power, a second lens with negative refractive power, a third lens with positive refractive power, a fourth lens with positive refractive power, a fifth lens with positive refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power, and an eighth lens with positive refractive power; or, the plurality of lenses comprises a first lens with negative refractive power, a second lens with negative refractive power, a third lens with positive refractive power, a fourth lens with positive refractive power, a fifth lens with negative refractive power, a sixth lens with negative refractive power, a seventh lens with positive refractive power, an eighth lens with negative refractive power, a ninth lens with positive refractive power, and a tenth lens with positive refractive power, and at least one of the fourth lens, the fifth lens, and the sixth lens is a cylindrical lens.

[0016] Further, the focal length EFL of the projection lens module is greater than or equal to 5mm and less than or equal to 8mm; the total track length TTL of the projection lens module satisfies TTL≤85mm; and the maximum field of view fov of the projection lens module is greater than or equal to 56.5°.

[0017] Further, the focal length EFL_x of the projection lens module in the x direction is greater than or equal to 8.0mm and less than or equal to 10.0mm; and / or the focal length EFL_y of the projection lens module in the y direction is greater than or equal to 5.0mm and less than or equal to 7.0mm.

[0018] Further, the first reflector is further included, and the first reflector is located on the light exit side of the light splitting module and is used to receive the light emitted by the light splitting module and reflect the light to the projection target surface to form a projection picture.

[0019] Further, at least one second reflector is further included, and the second reflector is located between the lenses of the projection lens module and / or the second reflector is located on the first side of the projection lens module and between the light splitting module and the projection lens module; the second reflector is used to change the exit angle of the light path of the projection lens module.

[0020] Further, the reflecting surface of the first reflector is a free surface.

[0021] Further, the reflecting surface of the at least one second reflector is a free surface.

[0022] By using the technical scheme of the present application, the split-screen projection device includes a projection lens module and a light splitting module; the projection lens module sequentially includes a plurality of lenses with refractive power and an imaging light valve from the first side to the second side; the light splitting module is located on the first side of the projection lens module and on the optical axis of the projection lens module, and has a plurality of reflecting surfaces; the reflecting directions of the plurality of reflecting surfaces are different; and the plurality of reflecting surfaces are used to receive all the projection light of the projection lens module and reflect the projection light to different positions to form a plurality of projection pictures.

[0023] By arranging the light splitting module to have a plurality of reflecting surfaces and planning the reflecting directions of the plurality of reflecting surfaces to be different, all the projection light of the projection lens module is received by the plurality of reflecting surfaces of the light splitting module, and the different reflecting surfaces reflect the received projection light to different positions to form a plurality of projection pictures on the projection target surface, so that the light splitting module of the present application can realize the split-screen projection function in cooperation with the projection lens module, can form a plurality of independent projection pictures on the projection target surface, and uses the reflecting surfaces to realize the turning of the light path of the projection light, which is beneficial to avoiding the loss of light and ensuring the light transmission efficiency and the imaging quality. In addition, the split-screen projection device of the present application has the advantages of simple structure and good projection quality, and does not need to use high-energy-consumption imaging light valves, thereby saving the cost. BRIEF DESCRIPTION OF DRAWINGS

[0024] The accompanying drawings, which form a part of this specification, are included to provide a further understanding of the application, and are incorporated herein by reference. The embodiments of the present application, together with its

[0025] Fig. 1 shows a structural schematic diagram of a split-screen projection device according to an embodiment of the present application;

[0026] Fig. 2 shows a whole projection effect diagram of the split-screen projection device in Fig. 1;

[0027] Fig. 3 shows a partial projection effect diagram of the split-screen projection device in Fig. 1;

[0028] Fig. 4 shows a projection schematic diagram of a split-screen projection device according to another embodiment of the present application;

[0029] Fig. 5 shows a schematic diagram of a projection picture of the split-screen projection device according to the embodiment of the present application on a target projection picture;

[0030] Fig. 6 shows a schematic diagram of the split-screen projection device according to the embodiment of the present application after adjusting the size of the projection picture;

[0031] Fig. 7 shows another schematic diagram of the split-screen projection device according to the embodiment of the present application after adjusting the size of the projection picture;

[0032] Fig. 8 shows a structural schematic diagram of a projection lens module of the split-screen projection device according to the embodiment of the present application in the meridian direction and the sagittal direction;

[0033] Fig. 9 shows a structural schematic diagram of a split-screen projection device according to another embodiment of the present application;

[0034] Fig. 10 shows a projection effect diagram of the split-screen projection device in Fig. 9 and a traditional projection lens;

[0035] Fig. 11 shows a structural schematic diagram of a split-screen projection device according to a first embodiment of the present application;

[0036] Fig. 12 shows a structural schematic diagram of a split-screen projection device according to a second embodiment of the present application;

[0037] Fig. 13 shows a structural schematic diagram of a split-screen projection device according to a first embodiment of the present application;

[0038] Fig. 14 shows a structural schematic diagram of a split-screen projection device according to a second embodiment of the present application;

[0039] Wherein, the above-mentioned drawings include the following reference signs: 10, light splitting module; 11, first reflecting surface; 12, second reflecting surface; L1, first lens; L2, second lens; L3, third lens; L4, fourth lens; L5, fifth lens; L6, sixth lens; L7, seventh lens; L8, eighth lens; L9, ninth lens; L10, tenth lens; STOP, diaphragm; 20, prism; 30, protective glass; 40, DMD chip; 51, first projected picture; 52, second projected picture. DETAILED DESCRIPTION

[0040] It should be noted that the embodiments and features of the embodiments in the present application can be combined with each other without conflict. The present application will be described in detail below with reference to the drawings and in combination with the embodiments.

[0041] It should be noted that, unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0042] In the present application, unless otherwise specified, the orientation words such as "upper", "lower", "top", "bottom" are generally directed to the directions shown in the drawings, or are directed to the vertical, perpendicular or gravity directions of the components themselves; similarly, for the convenience of understanding and description, "inner" and "outer" refer to the inner and outer relative to the contour of the components themselves, but the above orientation words are not used to limit the present application.

[0043] It should be noted that in the present specification, the expressions of first, second, third, etc. are only used to distinguish one feature from another feature, and do not represent any limitation on the features.

[0044] In this context, the paraxial region refers to the region near the optical axis. If the lens surface is convex and the position of the convex surface is not specified, it means that the lens surface is convex at least in the paraxial region; if the lens surface is concave and the position of the concave surface is not specified, it means that the lens surface is concave at least in the paraxial region. The surface of each lens near the first side becomes the first side surface of the lens, and the surface of each lens near the second side is called the second side surface of the lens. The judgment of the surface shape in the paraxial region can be based on the judgment method of those skilled in the art, with R value, (R refers to the radius of curvature in the paraxial region, usually refers to the R value on the lens data in the optical software) to judge the convexity and concavity. In terms of the first side surface, when the R value is positive, it is determined to be convex, and when the R value is negative, it is determined to be concave; in terms of the second side surface, when the R value is positive, it is determined to be concave, and when the R value is negative, it is determined to be convex.

[0045] In the present application, the left side of the projection lens module is the first side, and the right side is the second side. In the specific embodiments of the present application, the first side of the projection lens module is the projection side, and the second side is the light valve side. When projecting, the light from the light valve can be imaged on the projection side.

[0046] In order to solve the problems of complex structure and poor imaging quality of the split-screen projection device in the prior art, the present application provides a split-screen projection device.

[0047] As shown in FIGS. 1-10, the split-screen projection device comprises a projection lens module and a light splitting module 10. The projection lens module comprises a plurality of lenses with refractive power and a light valve in sequence from the first side to the second side. The light splitting module 10 is located on the first side of the projection lens module and on the optical axis of the projection lens module. The light splitting module 10 has a plurality of reflecting surfaces. The reflecting surfaces have different reflecting light directions. The plurality of reflecting surfaces are used to receive all the projection light of the projection lens module and reflect it to different positions to form a plurality of projection images.

[0048] By providing the light splitting module 10 with a plurality of reflecting surfaces and planning the reflecting light directions of the plurality of reflecting surfaces to be different, all the projection light of the projection lens module is received by the plurality of reflecting surfaces of the light splitting module 10, and the different reflecting surfaces reflect the received projection light to different positions to form a plurality of projection images on the projection target surface. The light splitting module 10 of the present application can realize the split-screen projection function in combination with the projection lens module, and can form a plurality of independent projection images on the projection target surface. The use of reflecting surfaces to realize the turning of the projection light path is beneficial to avoiding the loss of light and ensuring the light transmission efficiency, thereby ensuring the imaging quality. In addition, the split-screen projection device of the present application has the advantages of simple structure and good projection quality. Moreover, the split-screen projection device of the present application does not need to use high-energy consumption light valves, thereby saving costs.

[0049] It should be noted that the projection light emitted by the projection lens module can be received by the light splitting module 10 in its entirety, specifically by the plurality of reflecting surfaces. The plurality of reflecting surfaces reflect the received projection light to the projection target surface to form a plurality of projection images on the projection target surface. The contents displayed by the plurality of projection images can be the same or different, and the plurality of projection images are arranged at intervals.

[0050] It should be further noted that the above-mentioned light valve comprises one of a DMD chip 40, an LCOS chip, and an LCD screen, which can be set according to actual needs.

[0051] As shown in FIG. 1 and FIG. 9, the plurality of reflecting surfaces include a first reflecting surface 11 and a second reflecting surface 12, the first reflecting surface 11 is arranged at an angle with the optical axis, the second reflecting surface 12 is arranged at an angle with the optical axis, and the angle between the first reflecting surface 11 and the optical axis is the same as or different from the angle between the second reflecting surface 12 and the optical axis. In an optional embodiment of the present application, the angle between the first reflecting surface 11 and the optical axis is the same as the angle between the second reflecting surface 12 and the optical axis. In another optional embodiment of the present application, the angle between the first reflecting surface 11 and the optical axis is different from the angle between the second reflecting surface 12 and the optical axis, which can be set according to actual needs.

[0052] Specifically, the side of the light splitting module 10 facing the projection lens module has a first reflecting surface 11 and a second reflecting surface 12, and the area of the first reflecting surface 11 is the same as or different from the area of the second reflecting surface 12, which can be set according to actual conditions.

[0053] In an embodiment of the present application, the central axis of the light splitting module 10 coincides with the optical axis of the projection lens module, and the first reflecting surface 11 and the second reflecting surface 12 are arranged symmetrically with the optical axis as the axis of symmetry. That is, the connection position of the first reflecting surface 11 and the second reflecting surface 12 is on the optical axis, and the angle between the first reflecting surface 11 and the optical axis is the same as the angle between the second reflecting surface 12 and the optical axis. Such a setting makes half of the total projection light emitted by the projection lens module be received by the first reflecting surface 11 and the other half be received by the second reflecting surface 12, and since the angle between the first reflecting surface 11 and the optical axis is the same as the angle between the second reflecting surface 12 and the optical axis, the two projection pictures formed by the two reflecting surfaces transmitted to the projection target surface are of the same size and are arranged at intervals, and as shown in FIG. 2, the two projection pictures are a first projection picture 51 and a second projection picture 52.

[0054] In another embodiment of the present application, the central axis of the light splitting module 10 can also be parallel to and arranged at intervals with the optical axis of the projection lens module, so that the two projection pictures formed by the two reflecting surfaces transmitted to the projection target surface are of different sizes, which can be set according to actual conditions.

[0055] As shown in FIG. 1, the distance h from the vertex of the light splitting module 10 on the central axis to the light valve on the optical axis satisfies: 50mm≤h≤200mm. The vertex of the light splitting module 10 on the central axis specifically refers to the vertex of the side of the light splitting module 10 facing the projection lens module on the central axis. By reasonably planning the distance from the light splitting module 10 to the light valve, it is beneficial to ensure that the total projection light emitted by the projection lens module can be fully received by the light splitting module 10, thereby avoiding the case of picture loss, ensuring the integrity and stability of display, and at the same time, it is beneficial to compress h, ensuring the small volume of the split-screen projection device.

[0056] As shown in FIG. 2, the distance h between the vertex of the light splitting module 10 on the central axis and the projection target surface on the optical axis and the intercept H of the vertex of the light splitting module 10 on the central axis to the projection target surface satisfy: 0.8≤H / h≤2. The intercept of the vertex of the light splitting module 10 on the central axis to the projection target surface specifically refers to the vertical distance from the vertex of the light splitting module 10 on the central axis to the projection target surface. By reasonably constraining H / h, the overall length of the split-screen projection device can be compressed while ensuring imaging stability and imaging integrity, thereby ensuring a small volume.

[0057] Specifically, the angle a between the reflecting surface and the optical axis of the projection lens module satisfies: 0.6≤tan a≤3.5. Specifically, the angle between the first reflecting surface 11 and the optical axis of the projection lens module and the angle between the second reflecting surface 12 and the optical axis of the projection lens module are both a. Such a setting is conducive to the split-screen projection device to make the two projection pictures within a certain size range within the limited width direction range of the projection target surface, and to ensure the best projection effect.

[0058] As shown in FIG. 1 and FIG. 3, the projection light emitted by the projection lens module is split by the two reflecting surfaces and projected at a large angle. If the light cone angle is too large, the projection blind area will be too large. The projection blind area is the interval region between the first projection picture 51 and the second projection picture 52. Therefore, the angle a between the reflecting surface and the maximum field of view fov of the projection lens module satisfies: 0.7≤fov / a≤1.3. Such a setting makes the reflection angle of the projection lens module matched with the projection target surface size optimized. The parameters h, tan a, and fov are related to each other. By constraining h, tan a, and fov, the projection blind area is small, and the utilization rate of the imaging light valve is improved.

[0059] In optional embodiments of the present application, at least one of the plurality of lenses with refractive power in the projection lens module is a cylindrical lens or a free-form lens. This arrangement makes the focal length and magnification of the projection lens module different in the x direction and the y direction. This arrangement enables the split-screen projection device of the present application to be applied to special projection target surfaces, for example, in a car dashboard. The split-screen projection device is placed in the middle of the car console and projects images to the two side instrument panels respectively. The conventional instrument panel size is usually 1.5:1-4:1 in length to width ratio. The two reflecting surfaces and the optical axis of the split-screen projection device form an angle of a, and the projection images of the two reflecting surfaces are large-angle side projection. The projection images are large trapezoidal images, and the projection light cones at the outer edges often exceed the target projection range. To avoid too much projection image exceeding the instrument panel projection area, the field of view angle of the projection lens module can be reduced. However, this arrangement results in a small projection width size area at the inner edge, i.e., a small overall projection image. At this time, the present application uses a cylindrical lens or a free-form lens to design a large magnification in the width direction of the projection image and a small magnification in the length direction. In this way, a large projection image is obtained at the inner edge, and the outer edge covers the instrument panel area and exceeds the target projection range less, thereby increasing the effective projection area.

[0060] In specific embodiments of the present application, at least one of the plurality of lenses with refractive power in the projection lens module is a cylindrical lens. The focal length EFL_x of the projection lens module in the x direction and the focal length EFL_y of the projection lens module in the y direction satisfy: 1.1≤EFL_x / EFL_y≤1.8. This arrangement is conducive to the allocation of the focal lengths of the projection lens module in the two perpendicular directions and is conducive to ensuring the use reliability of the projection lens module. It should be noted that the optical axis of the projection lens module is perpendicular to the plane formed by the x direction and the y direction. This arrangement reduces the projection size of the projection lens module in the x direction, which is conducive to reducing the ineffective projection area.

[0061] Specifically, the magnification β2 of the projection lens module in the x direction and the magnification β1 of the projection lens module in the y direction satisfy: 0.5≤β1 / β2≤1.0. This arrangement constrains the relationship between the magnifications of the projection lens module in the x direction and the y direction, which is conducive to ensuring that the projection lens module can compress the size of the projection image in the x direction and appropriately increase the size of the projection image in the y direction, thereby adjusting the projection target surface to be covered by the projection image and increasing the effective projection area. This arrangement reduces the projection size of the projection lens module in the x direction, which is conducive to reducing the ineffective projection area.

[0062] Specifically, the projection lens module further comprises a prism 20 and a protective glass 30, the prism 20 and the protective glass 30 are located at the first side of the light valve, and the protective glass 30 is arranged close to the light valve relative to the prism 20.

[0063] The split-screen projection device of the present application will be described below in combination with specific embodiments.

[0064] Embodiment one

[0065] As shown in FIGS. 1-3, the split-screen projection device of embodiment one is described.

[0066] As shown in FIG. 1, the split-screen projection device comprises a projection lens module and a light splitting module 10, the light splitting module 10 is located at the first side of the projection lens module and on the optical axis of the projection lens module, and the central axis of the light splitting module 10 coincides with the optical axis of the projection lens module. The body of the light splitting module 10 can be a prism structure, and the side of the light splitting module 10 facing the projection lens module has a first reflecting surface 11 and a second reflecting surface 12. The first reflecting surface 11 and the second reflecting surface 12 have the same angle with the optical axis and are both α.

[0067] Specifically, the projection lens module is composed of eight lenses with refractive power. Specifically, the projection lens module comprises, in order from the first side to the second side, a first lens L1 with negative refractive power, a second lens L2 with negative refractive power, a third lens L3 with positive refractive power, a stop STOP, a fourth lens L4 with positive refractive power, a fifth lens L5 with positive refractive power, a sixth lens L6 with negative refractive power, a seventh lens L7 with positive refractive power, an eighth lens L8 with positive refractive power, a prism 20, a protective glass 30, and a DMD chip 40. Among them, the fifth lens L5 and the sixth lens L6 are glued to form a double-glued lens.

[0068] In the embodiment, the first side of the first lens L1 is convex, and the second side is concave. The first lens L1 has a meniscus shape and can converge large-angle light rays. Reasonably optimizing the curvature radius is conducive to correcting the distortion aberration. The first side of the second lens L2 is concave, and the second side is concave. The first side of the third lens L3 is concave, and the second side is convex. The first side of the fourth lens L4 is convex, and the second side is concave. The fourth lens L4 is arranged near the rear of the stop STOP, effectively alleviates the light deflection degree near the stop STOP, and effectively reduces the lens size while realizing the performance and tolerance sensitivity reduction of the projection lens module. The first side of the fifth lens L5 is concave, and the second side is convex. The first side of the sixth lens L6 is concave, and the second side is concave. The fifth lens L5 and the sixth lens L6 are set to be cemented as a double-cemented lens, wherein the refractive index nd1 and the Abbe number Vd1 of the fifth lens L5 and the refractive index nd2 and the Abbe number Vd2 of the sixth lens L6 satisfy nd1>nd2 and Vd1>Vd2. The first side of the seventh lens L7 is convex, and the second side is convex. The first side of the eighth lens L8 is convex, and the second side is a plane. To ensure stable optical performance in high and low temperature environments, the first lens L1 to the eighth lens L8 are glass lenses with good thermal stability.

[0069] As shown in FIG. 1 and FIG. 3, during projection, light rays enter the multi-lens from the side of the DMD chip 40 through the prism 20, and finally leave the projection lens module to irradiate the light splitting module 10. The first reflecting surface 11 and the second reflecting surface 12 divide the screen and project the screen on the projection target surface respectively. Half of the screen is reflected by the first reflecting surface 11 to form a first projection screen 51, and the other half of the screen is reflected by the second reflecting surface 12 to form a second projection screen 52. The first reflecting surface 11 and the second reflecting surface 12 are both high-reflectivity mirror surfaces. The distance between the vertex of the light splitting module 10 on the central axis and the axis of the object side of the first lens L1 is 32 mm. The distance between the vertex of the light splitting module 10 on the central axis and the light axis of the image light valve h is 107 mm. The angle α between the first reflecting surface 11, the second reflecting surface 12 and the light axis is 58°.

[0070] By optimizing the curvature, material properties, and spacing of each lens included in the optical system, a high-performance, low-distortion, fixed-focus projection lens module is obtained. The focal length EFL of the projection lens module is greater than or equal to 5 mm and less than or equal to 8 mm. The total optical length TTL of the projection lens module satisfies: TTL≤85 mm, where TTL is the axial distance from the first side of the first lens L1 to the DMD chip 40. The maximum field of view fov of the projection lens module is greater than or equal to 56.5°. The projection lens module is combined with the light splitting module 10 to obtain split-screen projection. The first projection image 51 and the second projection image 52 both have good imaging quality. The projection lens module in this embodiment has long-focus characteristics, and the maximum field of view fov is 56.5°.

[0071] Table 1 below shows the basic structure parameter table of the projection lens module of Example 1. The units of the curvature radius and thickness are both millimeters.

[0072] Table 1

[0073] In summary, the split-screen projection device provided in this embodiment can achieve multi-direction, ultra-short distance and long distance, high imaging quality projection. Based on the principles of optical imaging and basic physics, the curvature radius, material, thickness, and air spacing of each lens of the projection lens module are repeatedly optimized and designed using optical design software to achieve small aberration and high-quality connection. By designing and arranging the spatial position and size of the lens, each focal length module lens can be projected to different directional areas, achieving multi-directional projection image delivery. The overall design scheme is simple in structure, ingenious in design, high in production quantity, and easy to mass produce.

[0074] Example Two

[0075] As shown in FIGS. 4-10, a split-screen projection device of Example Two is described.

[0076] The difference from Example One is that the projection lens module is different. The projection lens module of this embodiment is composed of ten lenses with refractive power, and at least one of the ten lenses is a cylindrical lens.

[0077] As shown in FIG. 8 and FIG. 9, the projection lens module comprises, from the first side to the second side, a first lens L1 with a negative refractive power, a second lens L2 with a negative refractive power, a third lens L3 with a positive refractive power, a fourth lens L4 with a positive refractive power, a stop STOP, a fifth lens L5 with a negative refractive power, a sixth lens L6 with a negative refractive power, a seventh lens L7 with a positive refractive power, an eighth lens L8 with a negative refractive power, a ninth lens L9 with a positive refractive power, a tenth lens L10 with a positive refractive power, a prism 20, a protective glass 30 and a DMD chip 40, wherein the fourth lens L4, the fifth lens L5 and the sixth lens L6 are all cylindrical lenses. Such arrangement makes the projection lens module have different combined refractive powers in the meridional direction and the sagittal direction, i.e. different effective focal lengths in the meridional direction and the sagittal direction, wherein the meridional direction is the y direction mentioned above and the sagittal direction is the x direction mentioned above. Specifically, the focal length EFL_x of the projection lens module in the x direction is greater than or equal to 8.0 mm and less than or equal to 10.0 mm, and the focal length EFL_y of the projection lens module in the y direction is greater than or equal to 5.0 mm and less than or equal to 7.0 mm.

[0078] In the embodiment, the first side of the first lens L1 is convex, and the second side is concave. The first lens L1 is an aspheric lens, and the system distortion and the axial aberration are effectively corrected by reasonably optimizing the aspheric coefficients. The curvature radius of the first side of the first lens L1 ranges from 9 mm to 35 mm, and the curvature radius of the second side of the first lens L1 ranges from 5 mm to 20 mm. The first side and the second side of the second lens L2 are both concave. The curvature radius of the first side of the second lens L2 ranges from -25 mm to -10 mm, and the curvature radius of the second side of the second lens L2 ranges from 7 mm to 30 mm. The first side of the third lens L3 is convex, and the second side is convex. The curvature radius of the first side of the third lens L3 ranges from 20 mm to 40 mm, and the curvature radius of the second side of the third lens L3 ranges from -50 mm to -20 mm. The fourth lens L4 is a double-convex cylindrical lens. The curvature radius of the first side of the fourth lens L4 in the sagittal direction ranges from 10 mm to 50 mm, the curvature radius of the second side of the fourth lens L4 in the sagittal direction ranges from -100 mm to -20 mm, and the refractive power of the fourth lens L4 in the sagittal direction fg4x satisfies: 10 mm≤fg4x≤40 mm. The curvature radius of the two side surfaces of the fourth lens L4 in the meridional direction is infinite, and the refractive power is zero. The stop STOP is arranged between the fourth lens L4 and the fifth lens L5. The first side of the fifth lens L5 is a cylindrical surface with a curvature radius of 80 mm to 250 mm in the sagittal direction, and the second side of the fifth lens L5 is a spherical surface with a curvature radius of 80 mm to 250 mm. The refractive power of the fifth lens L5 in the sagittal direction fg5x satisfies: fg5x≤-100 mm, and the refractive power of the fifth lens L5 in the meridional direction fg5y satisfies: -200 mm≤fg5y≤-55 mm. The sixth lens L6 is a double-concave cylindrical lens. The curvature radius of the first side of the sixth lens L6 in the sagittal direction ranges from -50 mm to -10 mm, the curvature radius of the second side of the sixth lens L6 in the meridional direction ranges from 10 mm to 30 mm, the refractive power of the sixth lens L6 in the sagittal direction fg6x satisfies: -40 mm≤fg4x≤-10 mm, and the curvature radius of the two side surfaces of the sixth lens L6 in the meridional direction is infinite, and the refractive power is zero. The seventh lens L7 and the eighth lens L8 are cemented to form a double-cemented lens. The first side of the seventh lens L7 is convex, and the second side is convex. The curvature radius of the first side of the seventh lens L7 ranges from 10 mm to 30 mm, and the curvature radius of the second side ranges from -40 mm to -10 mm. The first side of the eighth lens L8 is concave, and the second side is concave. The curvature radius of the first side of the eighth lens L8 ranges from -40 mm to -10 mm, and the curvature radius of the second side ranges from 10 mm to 30 mm. The first side of the ninth lens L9 is concave, and the second side is convex.The first side of the ninth lens L9 has a curvature radius of 70mm-200mm, and the second side has a curvature radius of -25mm--10mm. The ninth lens L9 is an aspheric lens. The first side of the tenth lens L10 is concave, and the second side is convex. The first side of the tenth lens L10 has a curvature radius of -200mm--100mm, and the second side has a curvature radius of -30mm--10mm.

[0079] In the embodiment, the projection lens module has a focal length EFL_x of 9.9mm in the x direction, a focal length EFL_y of 6.82mm in the y direction, an aperture number Fno of 1.99, and a back focal length BFL of 20.5mm.

[0080] Table 2 below shows the basic structure parameter table of the projection lens module of the second embodiment. The units of the curvature radius and the thickness are both millimeters.

[0081] Table 2

[0082] The principle of the embodiment is that, as shown in FIG. 4 and FIG. 5, when the width of the target projection area is B and the length is A; in FIG. 4, the split projection device projects obliquely beyond the target projection area, as shown in FIG. 5, the trapezoidal area is the trapezoidal picture formed by the side projection, the rectangular area is the target projection area, and the trapezoidal picture corresponds to the projection area formed by the projection lens module with a magnification β matching the width B of the target projection area; at this time, the light beyond the length A is not effectively utilized. The magnification β = image height / object height, and in the projection lens module, β = DMD inch / Project inch.

[0083] To increase the effective projection area, i.e. to reduce the light cone beyond the target projection area, a cylindrical lens or a free-form lens is arranged in the projection lens module, so as to compress the projection size of the projection lens module in the long direction, i.e. the x direction, and increase the projection size of the projection lens module in the width direction, i.e. the y direction, as shown in FIG. 6. The projection lens module has different focal lengths and magnifications in the meridional direction and the sagittal direction. Specifically, the focal length EFL_x of the projection lens module in the x direction and the focal length EFL_y of the projection lens module in the y direction satisfy: 1.1≤EFL_x / EFL_y≤1.8. The magnification β2 of the projection lens module in the x direction and the magnification β1 of the projection lens module in the y direction satisfy: 0.5≤β1 / β2≤1.0. The magnification β1 matches the width B; and the magnification β2 matches the length A. Since the long direction size of the projection picture is reduced, the side projection long direction of the split-screen projection device is also compressed, as shown in FIG. 7, and the range beyond the target projection area is greatly reduced, and the light efficiency and chip utilization rate are improved by 20%.

[0084] FIG. 10 shows a projection effect diagram of a projection lens module of the embodiment and a conventional projection lens. As can be seen from the diagram, the chip utilization rate of the embodiment is improved.

[0085] Embodiment Three

[0086] As shown in FIGS. 11-12, a split-screen projection device of embodiment three is described.

[0087] The difference between embodiments one and two is that a device with reflection capability, hereinafter referred to as a reflector, is further included, and the number of reflectors is greater than or equal to one.

[0088] Specifically, the light splitting module 10 is located on the first side of the projection lens module and on the optical axis of the outgoing light of the projection lens module. The central axis of the light splitting module 10 can coincide with the optical axis of the outgoing light of the projection lens module. For some special structure design, such as the light splitting module 10 with asymmetric design, the central axis does not coincide with the optical axis of the outgoing light of the projection lens module. The body of the light splitting module 10 can be a prism structure. The side of the light splitting module 10 facing the projection lens module has a first reflecting surface 11 and a second reflecting surface 12. The included angle between the first reflecting surface 11 and the second reflecting surface 12 and the outgoing light optical axis of the projection lens module is the same and is α. The reflector includes a first reflector R1 located on the light exit side of the light splitting module 10, used to receive the outgoing light of the light splitting module 10, and reflect the outgoing light onto the projection target surface to form a projection picture. The reflecting surface of the first reflector R1 is a free-form surface, which can correct the shape of the picture. The more the first reflector R1, the greater the correction ability of the picture quality.

[0089] Further, the number and the setting position of the first reflector R1 can be adjusted according to the structure of the light splitting module 10.

[0090] In the embodiment, as shown in FIG. 11, the reflector further comprises a second reflector R2, which is located on the light path of the projection lens module and used to change the exit angle of the light path of the projection lens module, for example, to turn the light path of the projection lens module by 90°. The second reflector R2 can be arranged between the lenses of the projection lens module, for example, between the first lens L1 and the second lens L2, or arranged on the first side of the projection lens module between the light splitting module 10 and the projection lens module. The second reflector R2 can change the light exit direction of the projection lens module, so as to make the arrangement of the projection lens module more flexible.

[0091] Further, the reflecting surface of the second reflector R2 is a free surface, which can correct the shape of the picture. The reflecting surface of the second reflector R2 can also be a plane or a spherical surface.

[0092] Taking the case that the second reflector R2 is arranged between the lenses of the projection lens module as an example, the projection lens module comprises, in sequence from the first side to the second side, a first lens L1 with positive refractive power, the second reflector R2, a second lens L2 with positive refractive power, a third lens L3 with negative refractive power, a fourth lens L4 with positive refractive power, a fifth lens L5 with positive refractive power, a stop STOP, a sixth lens L6 with negative refractive power, a seventh lens L7 with negative refractive power, an eighth lens L8 with positive refractive power, a ninth lens L9 with negative refractive power, a tenth lens L10 with positive refractive power, an eleventh lens L11 with positive refractive power, a prism 20, a protective glass 30 and a DMD chip 40. The third lens L3, the fourth lens L4 and the fifth lens L5 are all free surfaces.

[0093] In the embodiment, the focal length EFL_x of the projection lens module in the x direction is -5.14 mm, the focal length EFL_y of the projection lens module in the y direction is -5.67 mm, and the back focal length BFL of the projection lens module is 21.4 mm.

[0094] Table 3 below shows the basic structure parameter table of the projection lens module of the third embodiment. The units of the curvature radius and the thickness are both millimeters.

[0095] Table 3

[0096] The principle of the embodiment is that the optical axis is deflected 90° by the second reflector R2 between the first lens L1 and the second lens L2 to meet the positional relationship between the projector and the projection screen. During projection, the light rays enter the multiple lenses from the side of the DMD chip 40 through the prism 20, and finally exit the projection lens module to irradiate the light splitting module 10. The first reflecting surface 11 and the second reflecting surface 12 of the light splitting module 10 split the screen and irradiate on the first reflector R1 respectively, and finally project on the projection target surface. In order to improve the image quality and increase the effective projection area, free-form reflectors can also be continuously added to adjust the aberration and light cone size in multiple reflections, improve the projection quality, the projection area and improve the chip utilization rate.

[0097] Embodiment Four

[0098] As shown in FIGS. 13-14, a split-screen projection device of embodiment four is described.

[0099] One of the differences from embodiment three is that the number of second reflectors R2 in this embodiment is different.

[0100] As shown in FIG. 13, the light splitting module 10 is located on the first side of the projection lens module and on the optical axis of the exiting light of the projection lens module. The central axis of the light splitting module 10 can coincide with the optical axis of the exiting light of the projection lens module. For some special structure designs, such as the light splitting module 10 with asymmetric design, the central axis will not coincide with the optical axis of the exiting light of the projection lens module. The body of the light splitting module 10 can be a prism structure. The side of the light splitting module 10 facing the projection lens module has a first reflecting surface 11 and a second reflecting surface 12. The included angle of the first reflecting surface 11 and the second reflecting surface 12 with the optical axis of the exiting light of the projection lens module is the same and is α.

[0101] In this embodiment, as shown in FIG. 13, in the projection lens module, there is a second reflector R2 on the first side of the stop, which is used to make a certain angle of turn of the light path of the projection lens module. There is another second reflector R2 on the second side of the stop, which is used to make a certain angle of turn of the light path of the projection lens module, for example, 90°.

[0102] Specifically, from the first side to the second side, there are in sequence a first lens L1 with positive refractive power, a second lens L2 with negative refractive power, a second reflector R2, a third lens L3 with negative refractive power, a stop, a fourth lens L4 with negative refractive power, a second reflector R2, a fifth lens L5 with positive refractive power, a sixth lens L6 with negative refractive power, a seventh lens L7 with positive refractive power, an eighth lens L8 with positive refractive power, a ninth lens L9 with positive refractive power, a prism 20, a protective glass 30 and a DMD chip 40. The reflecting surface of the second reflector R2 between the stop and the first side is a free-form surface.

[0103] In the embodiment, the focal length of the projection lens module in the x direction is EFL_x=-11.7mm, the focal length of the projection lens module in the y direction is EFL_y=-10.6mm, and the back focal length of the projection lens module is BFL=22.3mm.

[0104] Table 4 below shows a basic structure parameter table of the projection lens module of Example Four. In the table, the units of the radius of curvature and the thickness are millimeters.

[0105] Table 4

[0106] The principle of the embodiment is that, during projection, light rays enter the lens module from the side of the DMD chip 40 through the prism 20, are irradiated onto the second reflector after passing through the fifth lens, are turned by 90° in the optical path, then enter the fourth lens and the third lens, are irradiated onto another second reflector, are turned by a certain angle again in the optical path, then enter the second lens and the first lens, are then irradiated onto the light splitting module 10, the first reflecting surface 11 and the second reflecting surface 12 of the light splitting module 10 split the picture, and the second reflector cooperates with the light splitting module to project the final picture onto the projection target surface. The cooperation of the second reflector can make the volume of the optical lens more flexible and adapt to more structure envelopes. Setting the reflecting surface of the second reflector as a free-form surface can also correct the shape of the picture.

[0107] Further, a first reflector R1 can be arranged on the light exit side of the light splitting module 10 according to the projection needs, for receiving the exit light of the light splitting module 10 and reflecting the exit light onto the projection target surface to form a projection picture, and the reflecting surface of the first reflector R1 is a free-form surface. It can be understood that the first reflector R1 can also not be arranged.

[0108] To improve the image quality and increase the effective projection area, a free-form surface reflector can be further arranged behind the light splitting module to adjust the aberration and the light cone size in multiple reflections, improve the projection quality, the projection area, and improve the chip utilization rate.

[0109] Obviously, the above-described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the protection scope of the present application.

[0110] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting, as the scope of the exemplary embodiments of this application is limited only by the appended claims. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Also, unless otherwise indicated herein, the materials described herein can be used in a variety of applications.

[0111] It should be noted that the terms "first", "second", and the like, as used herein, are intended to modify any one of the identified objects, but do not imply a specific order or sequence, unless otherwise specifically indicated. It is to be understood that the use of the term "about" in describing the embodiments of this application is intended to convey that the description is an approximation, and that the embodiments of this application are not limited to the precise values, ranges, or parameters described, unless otherwise specifically indicated.

[0112] The preferred embodiments of the application are described above in detail. The application is not limited to the embodiments described above, but can vary and be modified, as can occur to those skilled in the art. Any equivalent realizations, modifications, and improvements made without departing from the spirit and principles of the application shall fall within the scope of protection of the application.

Claims

1. A split projection device, characterized by, The projection lens module sequentially comprises a plurality of lenses with refractive power and a light valve from the first side to the second side. The light splitting module (10) is located on the first side of the projection lens module and on the optical axis of the projection lens module, and has a plurality of reflecting surfaces with different reflection directions, which are used to receive the projection light of the projection lens module and reflect to different positions to form a plurality of projection images. The plurality of reflecting surfaces includes a first reflecting surface (11) and a second reflecting surface (12), the first reflecting surface (11) is arranged at an angle with the optical axis, and the second reflecting surface (12) is arranged at an angle with the optical axis, and the included angle between the first reflecting surface (11) and the optical axis is the same as or different from the included angle between the second reflecting surface (12) and the optical axis.

2. The split projection device of claim 1, wherein, The central axis of the light splitting module (10) coincides with the optical axis of the projection lens module, the plurality of reflecting surfaces includes a first reflecting surface (11) and a second reflecting surface (12), and the first reflecting surface (11) and the second reflecting surface (12) are symmetrically arranged with the optical axis as the axis of symmetry.

3. The apparatus of claim 1, wherein, 4. The split-screen projection device according to claim 1, wherein The distance h from the vertex on the central axis of the light splitting module (10) to the light valve on the optical axis satisfies: 50mm≤h≤200mm; and / or The distance h from the vertex on the central axis of the light splitting module (10) to the light valve on the optical axis and the intercept H between the vertex on the central axis of the light splitting module (10) and the projection target surface satisfy: 0.8≤H / h≤2. The included angle α between the reflecting surface and the optical axis of the projection lens module satisfies: 0.6≤tanα≤3.

5.

5. The apparatus of claim 4, wherein, The included angle α between the reflecting surface and the optical axis and the maximum field of view angle fov of the projection lens module satisfy: 0.7≤fov / α≤1.

3.

6. The split -projection device of claim 5, wherein, At least one of the plurality of lenses with refractive power is a cylindrical lens or a free-form surface lens, and the focal length and magnification of the cylindrical lens or the free-form surface lens in the x direction and the y direction are different.

7. The split projection device of any one of claims 1 to 6, wherein, The focal length EFL_x of the projection lens module in the x direction and the focal length EFL_y of the projection lens module in the y direction satisfy: 1.1≤EFL_x / EFL_y≤1.

8.

8. The split -projection device of claim 7, wherein, The magnification β2 of the projection lens module in the x direction and the magnification β1 of the projection lens module in the y direction satisfy: 0.5≤β1 / β2≤1.

0.

9. The apparatus of claim 7, wherein, 10. The split-screen projection device according to any one of claims 1 to 6, wherein The plurality of lenses includes a first lens (L1) with negative refractive power, a second lens (L2) with negative refractive power, a third lens (L3) with positive refractive power, a fourth lens (L4) with positive refractive power, a fifth lens (L5) with positive refractive power, a sixth lens (L6) with negative refractive power, a seventh lens (L7) with positive refractive power, and an eighth lens (L8) with positive refractive power; or ​ The multi-lens includes a first lens (L1) having a negative refractive power, a second lens (L2) having a negative refractive power, a third lens (L3) having a positive refractive power, a fourth lens (L4) having a positive refractive power, a fifth lens (L5) having a negative refractive power, a sixth lens (L6) having a negative refractive power, a seventh lens (L7) having a positive refractive power, an eighth lens (L8) having a negative refractive power, a ninth lens (L9) having a positive refractive power, and a tenth lens (L10) having a positive refractive power, and at least one of the fourth lens (L4), the fifth lens (L5), and the sixth lens (L6) is a cylindrical lens.

11. The split projection device according to claim 10, wherein, a focal length EFL of the projection lens module is greater than or equal to 5 mm and less than or equal to 8 mm; an overall optical length TTL of the projection lens module satisfies TTL≤85 mm; a maximum field of view angle fov of the projection lens module is greater than or equal to 56.5°.

12. The split projection device according to claim 10, wherein, a focal length EFL_x of the projection lens module in an x direction is greater than or equal to 8.0 mm and less than or equal to 10.0 mm; and / or, a focal length EFL_y of the projection lens module in a y direction is greater than or equal to 5.0 mm and less than or equal to 7.0 mm.

13. The split -projection device of any one of claims 1, wherein, Further comprising: a first reflector (R1) located on an outgoing light side of the light splitting module (10) for receiving outgoing light of the light splitting module (10) and reflecting the outgoing light onto a projection target surface to form a projection picture.

14. The apparatus according to claim 1 or 13, wherein, Further comprising: at least one second reflector (R2) located between lenses of the projection lens module and / or located on a first side of the projection lens module and between the light splitting module (10) and the projection lens module; the second reflector (R2) is configured to change an outgoing angle of a light path of the projection lens module.

15. The apparatus of claim 13, wherein, a reflecting surface of the first reflector (R1) is a free-form surface.

16. The apparatus of claim 14, wherein, a reflecting surface of at least one of the second reflectors (R2) is a free-form surface.

Images