Lens, projection device, vehicle lamp device and vehicle

Abstract

The embodiment of the invention provides a lens, a projection device, a vehicle lamp device and a vehicle, and belongs to the technical field of optics. The lens comprises a lens group and a diaphragm. Wherein the lens group comprises at least five lenses arranged from the image side to the object side, the number of the lenses with focal power in the lens group is at least five, and the number of the lenses with negative focal power in the lens group is at least one. The diaphragm comprises a first side and a second side which are oppositely arranged in the direction from the image side to the object side, at least one of the first side and the second side is provided with a lens, and when the lens is arranged on the first side, the lens which is located on the first side and closest to the diaphragm has negative focal power. And / or when the second side is provided with the lens, the lens which is located on the second side and closest to the diaphragm has negative focal power. By means of the arrangement, the lens can be matched with direct display chips such as the micro light-emitting diode display chip to form a small-size projection device, and therefore the size of the vehicle lamp device can be reduced.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the optical technical field, in particular to a lens, a projection device, a vehicle lamp device and a vehicle. BACKGROUND

[0002] With the development of intelligent automobile technology, it is required that the vehicle-mounted headlamp has a traditional lighting function and a projectable pattern to meet more and more needs of welcoming, information interaction, automatic driving and the like. In the related art, the vehicle lamp device includes a lens, a modulation device, a light source and a curved mirror. The curved mirror is configured to reflect a light beam emitted by the light source to the modulation device. The modulation device is a liquid crystal on silicon (LCOS). The modulation device modulates an imaging light beam according to the light beam from the curved mirror and emits the imaging light beam to the lens. However, in order to meet the arrangement requirements of the modulation device, the light source and the curved mirror and the like, the back focal length of the lens is relatively long, which leads to a large volume of the vehicle lamp device, thereby increasing the difficulty of arranging the vehicle lamp device in the vehicle. SUMMARY

[0003] Embodiments of the present application provide a lens, a projection device, a vehicle lamp device and a vehicle. The lens has a small back focal length, can be matched with a direct display chip such as a micro light emitting diode display chip to form a projection device with a small volume, thereby reducing the volume of the vehicle lamp device, and further reducing the difficulty of arranging the vehicle lamp device in the vehicle.

[0004] A first aspect of the present application provides a lens. The lens includes a lens group and a diaphragm. The lens group includes at least five lenses arranged from an image side to an object side. The number of lenses with optical power in the lens group is at least five. The number of lenses with negative optical power in the lens group is at least one. The diaphragm includes a first side and a second side oppositely arranged along a direction from the image side to the object side. The first side is close to the image side, and the second side is close to the object side. At least one of the first side and the second side is provided with a lens. When the first side is provided with a lens, the lens located on the first side and closest to the diaphragm has negative optical power. And / or, when the second side is provided with a lens, the lens located on the second side and closest to the diaphragm has negative optical power.

[0005] The rear focal length of the lens provided by the embodiments of the present application is small, so that the lens can be matched with a direct display chip such as a micro light emitting diode display chip to form a projection device with small volume, and the projection device is applied to a vehicle lamp device, so that the volume of the vehicle lamp device can be reduced, and the difficulty of arranging the vehicle lamp device in a vehicle is reduced. In addition, the lens can have the characteristics of a large aperture and a large field of view, the imaging range of the lens can be increased, the lens can be matched with a direct display chip with a large target surface, for example, a direct display chip with a million pixels, that is, the large target surface design of the lens can be realized, the increase of the light emitting area is beneficial, so that the light emitting power of the projection device can be improved, and the brightness of the projection device can be improved. In addition, the optical performance of the lens can be improved, so that the imaging quality is improved, and the distortion is reduced.

[0006] In a possible implementation, the lens satisfies the relationship: 4.5mm < BFL < 10mm, where BFL is the rear focal length of the lens.

[0007] In this way, by controlling the rear focal length of the lens to be between 4.5mm and 10mm, the distance between the lens and the direct display chip such as the micro light emitting diode display chip can be further reduced, and the volume of the projection device can be further reduced. In addition, the lens can also have the characteristics of a large aperture and a large field of view.

[0008] In a possible implementation, the lens satisfies the relationship: 30.02mm < R1 < 100mm, where R1 is the radius of curvature of the image side surface of the lens closest to the image side in the lens group.

[0009] In this way, by making the lens satisfy the relationship: 30.02mm < R1 < 100mm, the manufacturing difficulty of the lens closest to the image side in the lens group can be reduced under the premise of realizing a large aperture and a large field of view at the same time, the yield is improved, and the economy is improved. In addition, the correction of aberration can be facilitated, and the optical performance of the lens is improved. In addition, the image side surface of the lens closest to the image side can be effectively balanced with the optical performance of the lens and the modeling of the vehicle lamp.

[0010] In a possible implementation, the lens satisfies the relationship: 15mm < R2 < 30mm, where R2 is the radius of curvature of the object side surface of the lens closest to the object side in the lens group.

[0011] In this way, by making the lens satisfy the relationship: 15mm < R2 < 30mm, the manufacturing difficulty of the lens closest to the object side in the lens group can be reduced under the premise of realizing a large aperture and a large field of view at the same time, the yield is improved, and the economy is improved. In addition, the object side surface of the lens closest to the object side can be effectively balanced with the optical performance of the lens and the modeling of the vehicle lamp.

[0012] In a possible implementation, the first side and the second side are each provided with a lens.

[0013] In this way, the diaphragm is arranged between the lens closest to the image side in the lens group and the lens closest to the object side in the lens group, which can further reduce the volume of the lens and improve the economy of the lens.

[0014] In a possible implementation, at least one lens in the lens group is an aspherical lens with optical power.

[0015] In this way, the aspherical lens capable of correcting aberration is arranged in the lens group, which can further improve the optical performance of the lens and improve the imaging quality.

[0016] In a possible implementation, all lenses with optical power in the lens group are spherical lenses.

[0017] In this way, while the lens has the characteristics of a large aperture and a large field of view, the manufacturing difficulty of each lens can be reduced, thereby reducing the cost of the lens and further improving the economy of the lens.

[0018] In a possible implementation, the number of lenses with negative optical power in the lens group is one.

[0019] In this way, while the lens has the characteristics of a large aperture and a large field of view, the influence of the lens with negative optical power on the optical power of the lens can be reduced, thereby further improving the comprehensive performance of the lens.

[0020] The second aspect of the present application provides a projection device, which comprises a display unit and the lens according to any one of the first aspect. The display surface of the display unit is opposite to the lens closest to the object side in the lens, and the display unit is configured to form a display image and transmit the display image to the lens through the display surface.

[0021] Since the lens has a small back focal length and a large target surface design, the lens can be matched with a display unit with at least a million pixels, which not only can reduce the volume of the projection device, but also can improve the brightness of the projection device. In addition, the structure of the projection device can be simplified, and the performance of the projection device can be improved.

[0022] In a possible implementation, the display unit is a micro light-emitting diode display chip, a sub-millimeter light-emitting diode display chip, or a thin film field effect transistor display chip.

[0023] In this way, the display unit adopts the display chip integrated with the array light source of the micro light-emitting diode, the sub-millimeter light-emitting diode, etc., which simplifies the structure of the projection device and can also reduce the volume of the projection device.

[0024] The third aspect of the present application provides a vehicle lamp device, which comprises a housing and the projection device according to any one of the second aspect, and at least part of the projection device is arranged inside the housing.

[0025] The fourth aspect of the present application provides a vehicle, which comprises the vehicle lamp device according to the third aspect. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A structural schematic diagram of a vehicle lamp device provided in the related art;

[0027] Figure 2 A structural schematic diagram of a vehicle lamp device provided in an embodiment of the present application;

[0028] Figure 3 A structural schematic diagram of a lens provided in an embodiment of the present application;

[0029] Figure 4 A structural schematic diagram of a projection device provided in the first embodiment of the present application;

[0030] Figure 5 A spherical aberration diagram of the lens in the first embodiment of the present application; Figure 4

[0031] A field curvature diagram of the lens in the first embodiment of the present application; Figure 6 Figure 4 A distortion diagram of the lens in the first embodiment of the present application;

[0032] Figure 7 Figure 4 A structural schematic diagram of a projection device provided in the second embodiment of the present application;

[0033] Figure 8 A spherical aberration diagram of the lens in the second embodiment of the present application;

[0034] Figure 9 A field curvature diagram of the lens in the second embodiment of the present application; Figure 8

[0035] A distortion diagram of the lens in the second embodiment of the present application; Figure 10 Figure 8 A structural schematic diagram of a projection device provided in the third embodiment of the present application;

[0036] Figure 11 Figure 8 A spherical aberration diagram of the lens in the third embodiment of the present application;

[0037] Figure 12 A field curvature diagram of the lens in the third embodiment of the present application;

[0038] Figure 13 A distortion diagram of the lens in the third embodiment of the present application; Figure 12

[0039] Figure 14 Figure 12 ​​​​​​The image in the shot is like a fade-out curve;

[0040] Figure 15 for Figure 12 The distortion diagram of the lens in the image;

[0041] Figure 16 This is a schematic diagram of the projection device provided in Embodiment 4 of this application;

[0042] Figure 17 for Figure 16 A spherical chromatic aberration diagram of the lens in the image;

[0043] Figure 18 for Figure 16 The image in the shot is like a fade-out curve;

[0044] Figure 19 for Figure 16 The distortion of the lens in the image.

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

[0046] 100. Vehicle lighting system;

[0047] 110. Outer shell;

[0048] 120. Projection device;

[0049] 130. Preset position;

[0050] 10. Lens; 101. Lens group; 102. Aperture stop; 103. Cover glass;

[0051] 20. Display unit;

[0052] 11. First lens; 12. Second lens; 13. Third lens; 14. Fourth lens; 15. Fifth 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 that faces the image side is the image-side surface of the lens.

[0057] The object side refers to the side where the display unit is located, and the side of the lens facing the object side is called the object side surface.

[0058] Total track length (TTL) refers to the total length from the vertex of the first lens element located near the object side to the image plane of the lens; it is also known as the total optical length.

[0059] Back focal length (BFL) is defined as the distance from the lens element closest to the imaging plane to the display unit.

[0060] Optical power is the ability of a lens to refract a parallel beam of light incident from an incident lens.

[0061] Positive focal length means that the lens has a positive focal length and has the effect of converging light.

[0062] Negative power means that the lens has a negative focal length, which has the effect of diverging light.

[0063] Aperture is a device used to control the amount of light passing through the lens into an electronic device. It is usually expressed in the lens using the F# (F-number) value.

[0064] The aperture number F# is a relative value derived from the lens's focal length and the lens's light-gathering diameter (the reciprocal of the relative aperture). The smaller the aperture number F#, the more light enters the lens in the same unit of time.

[0065] Cover glass (CG) is used to protect the display chip.

[0066] The target surface refers to the imaging part of the image sensor. In the embodiments of this application, it refers to the light-emitting surface of the displayed image (such as the display surface of the display unit). The larger the target surface, the larger the available light-emitting area for the displayed image, and the higher the brightness of the displayed image.

[0067] The field of view (FOV) is the angle between the two edges of the lens that allow the image to pass through the lens to its maximum extent. The size of the FOV determines the range of the lens's field of view; the larger the FOV, the wider the field of view.

[0068] 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.

[0069] 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.

[0070] Figure 1 This is a structural schematic diagram of a vehicle lighting device provided in related technologies.

[0071] In related technologies, see Figure 1 As shown, the vehicle lighting device includes a lens 210, a modulator 220, a light source 230, and a curved mirror 240. The curved mirror 240 is used to reflect the light beam emitted by the light source 230 to the modulator 220. The modulator 220 is a liquid crystal on silicon (LCOS). The modulator 220 modulates the imaging beam according to the light beam from the curved mirror 240 and outputs the imaging beam to the lens 210.

[0072] However, in order to meet the arrangement requirements of devices such as the modulation device 220, the light source 230, and the curved mirror 240, the back focal length of the lens 210 is relatively long, resulting in a large size of the vehicle lighting device and thus increasing the difficulty of its placement in a vehicle. Furthermore, the large number of components in the vehicle lighting device leads to its complex structure. In addition, the complex optical path within the vehicle lighting device results in low illumination efficiency.

[0073] In view of this, embodiments of this application provide a lens, a projection device, a vehicle lighting device, and a vehicle. The lens has a short back focal length, allowing it to be used with direct-view display chips such as micro-LED display chips to form a compact projection device. When applied to vehicle lighting devices, this reduces the size of the lighting device, thereby simplifying its installation in vehicles. Furthermore, the lens can possess a large aperture and a wide field of view, increasing its imaging range. This allows it to be used with large-area micro-LED display chips, such as those with tens of thousands of pixels. This enables a large-area design for the lens, increasing the light-emitting area and thus improving the luminous power and brightness of the projection device. Additionally, it improves the lens's optical performance, thereby enhancing image quality and reducing distortion.

[0074] The vehicles provided in this application embodiment may include, but are not limited to, automobiles, trucks, motorcycles, boats, airplanes, helicopters, lawnmowers, recreational vehicles, amusement park vehicles, construction equipment, trams, golf carts, trains, or handcarts. Furthermore, the vehicles provided in this application embodiment may also be new vehicles that will emerge in the future.

[0075] The term "car" can refer to electric vehicles, gasoline-powered vehicles, or hybrid vehicles, such as pure electric vehicles, range-extended electric vehicles, new energy vehicles, fuel cell vehicles, and hybrid electric vehicles. For example, the following explanation uses "car" as an example of the aforementioned means of transportation.

[0076] For example, a vehicle may include a lighting device 100 and a vehicle body. The vehicle body may include components that complete the structure or function of the vehicle, such as seats, dashboards, and body panels, including braking systems, drive systems, and sensors. The lighting device 100 has both illumination and projection functions, capable of providing illumination or fulfilling projection requirements.

[0077] The vehicle lighting device 100 may include, but is not limited to, pixel display vehicle lights, near-field welcome lights, pedestrian or interactive vehicle lights, and car headlights. For example, in this embodiment, a car headlight is used as an example of the vehicle lighting device 100. The car headlight can be installed at the front or rear of the car; therefore, the car headlight can fulfill both lighting and display requirements.

[0078] Figure 2 This is a structural schematic diagram of a vehicle lighting device 100 provided in an embodiment of this application.

[0079] See Figure 2 As shown, the vehicle lighting device 100 may include a housing 110 and a projection device 120. At least a portion of the projection device 120 is disposed inside the housing 110, for example... Figure 2 As shown, the projection device 120 is disposed inside the housing 110. Of course, the projection device 120 may also be partially disposed inside the housing 110 and partially disposed outside the housing 110. The projection device 120 is used to realize the lighting and other display needs of the vehicle lighting device 100.

[0080] It should be noted that the projection device 120 provided in this application embodiment can be applied not only to the vehicle lighting device 100, but also to projectors, head-up display (HUD) devices, augmented reality (AR) glasses and other devices to meet display requirements.

[0081] For example, see [link to previous article] Figure 2As shown, the projection device 120 may include a display unit 20 and a lens 10. The display surface of the display unit 20 is opposite to the lens closest to the object side of the lens 10; that is, the display unit 20 is disposed on the object side of the lens 10 and opposite to its display surface along the optical axis of the lens 10. The display unit 20 is configured to form a display image and transmit the display image through the display surface to the lens 10. The lens 10 can magnify, focus, and adjust the focus of the display image. After passing through the lens 10, the display image is projected onto a preset position 130, thus achieving the projection display of the image.

[0082] The preset position 130 can be understood as a structure used to support the display image projected by the projection device 120, thereby enabling the display of the image. The preset position 130 can be any structure capable of supporting the display image, such as a projection screen, vehicle window, glass, wall, or ground. For example, the projection device 120 can project the display image onto the ground in front of the vehicle, allowing passengers to see the display image while viewing the ground.

[0083] The display unit 20 can be a direct-view chip such as a micro-emitting diode (Micro LED) display chip, a sub-millimeter light-emitting diode (Mini LED) display chip, or a thin-film transistor (TFT) display chip. By using a display chip that integrates an array of light sources such as micro-emitting diodes or sub-millimeter light-emitting diodes with the chip, the structure of the display unit 20 is simplified, thereby simplifying the structure of the projection device 120 and reducing the size of the projection device 120.

[0084] Because the lens 10 provided in this application embodiment has a small back focal length and a large target surface design, the lens 10 can support a large target surface direct display chip, such as a direct display chip with at least tens of thousands of pixels. This not only reduces the size of the projection device 120, but also improves the brightness of the projection device 120.

[0085] The lens 10 provided in the embodiments of this application will now be described with reference to the accompanying drawings.

[0086] Figure 3 This is a schematic diagram of the structure of a lens 10 provided in an embodiment of this application.

[0087] See Figure 3 As shown, the lens 10 may include a lens group 101 and an aperture stop 102. The lens group 101 includes at least five lenses arranged from the image side to the object side, for example... Figure 3As shown, lens group 101 includes five lenses, which are a first lens 11, a second lens 12, a third lens 13, a fourth lens 14, and a fifth lens 15 arranged from the image side to the object side. Of course, the number of lenses in lens group 101 can also exceed five. The number of lenses with optical power in lens group 101 is at least five, for example... Figure 3 As shown, the lens group 101 contains five lenses with optical power; however, the number of lenses with optical power in the lens group 101 can also exceed five. The lens group 101 contains at least one lens with negative optical power, for example... Figure 3 As shown, the lens group 101 has one lens with negative optical power. Of course, the lens group 101 may have more than one lens with negative optical power.

[0088] See also Figure 3 As shown, the aperture stop 102 includes a first side and a second side disposed opposite to each other along the direction from the image side to the object side. The first side is closer to the image side, and the second side is closer to the object side. At least one of the first side and the second side is provided with a lens. When a lens is provided on the first side, the lens located on the first side and closest to the aperture stop 102 has negative optical power. And / or, when a lens is provided on the second side, the lens located on the second side and closest to the aperture stop 102 has negative optical power. That is, when there is one lens with negative optical power, the lens with negative optical power can be located on either the first side or the second side and disposed closest to the aperture stop 102, i.e., the aperture stop 102 is adjacent to the lens with negative optical power; or, when there are two or more lenses with negative optical power, two of the lenses with negative optical power are respectively located on the first side and the second side and respectively disposed closest to the aperture stop 102, i.e., the aperture stop 102 is located between the two lenses with negative optical power.

[0089] The negative optical power of the lens contributes negatively to the optical power of the lens 10. By placing the lens with negative optical power next to the aperture stop 102, the influence of the lens with negative optical power on the optical power of the lens 10 is reduced, which is conducive to giving full play to the overall performance of the lens and thus improving the overall performance of the lens 10.

[0090] By controlling the arrangement of the optical power of each lens in the lens group 101 and the positions of the aperture stop 102 and the lens with negative optical power, the back focal length of the lens 10 can be reduced and controlled within a reasonable range. This allows the lens 10 to cooperate with direct display chips such as micro LED display chips to form a small projection device 120. When the projection device 120 is applied to the vehicle lighting device 100, the size of the vehicle lighting device 100 can be reduced, thereby reducing the difficulty of arranging the vehicle lighting device 100 in a vehicle.

[0091] Furthermore, the lens 10 can possess the characteristics of a large aperture and a wide field of view, increasing the imaging range of the lens 10. This allows the lens 10 to be used with direct-view display chips such as large-area micro-LED display chips, for example, with direct-view display chips with tens of thousands of pixels. In other words, a large-area design for the lens 10 can be achieved, which is beneficial for increasing the light-emitting area, thereby increasing the light-emitting power of the projection device 120 and thus improving the brightness of the projection device 120. In addition, the optical performance of the lens 10 can be improved, thereby improving image quality and reducing distortion.

[0092] It should be noted that lens 10, in addition to using at least five lens elements with optical power (e.g., ...), Figure 3 In addition to being composed of five lenses with optical power, the lens 10 can also be composed of a portion of lenses with optical power and a portion of lenses without optical power. For example, the lens 10 may include five lenses with optical power and two lenses without optical power.

[0093] For example, see Figure 3 As shown, lenses can be provided on both the first and second sides. That is, by placing the aperture stop 102 between the lens closest to the image side and the lens closest to the object side in the lens group 101, the volume of the lens 10 can be further reduced and the economy of the lens 10 can be improved.

[0094] See Figure 3 As shown, a first lens 11 and a second lens 12 are provided on the first side, and a third lens 13, a fourth lens 14, and a fifth lens 15 are provided on the second side. Therefore, the number of lenses provided on the first side is different from the number of lenses provided on the second side. However, in some embodiments, the number of lenses provided on the first side and the number of lenses provided on the second side may be the same.

[0095] For example, the number of lenses with negative optical power in lens group 101 can be one, for example... Figure 3 As shown, there is one lens with negative optical power. At this time, the lens with negative optical power can be located on the first side or the second side and set closest to the aperture stop 102.

[0096] Given that lenses with negative optical power make a negative contribution to the optical power of lens 10, setting the number of lenses with negative optical power to one can further reduce the impact of lenses with negative optical power on the optical power of lens 10, and help to further improve the overall performance of lens 10.

[0097] In some possible implementations, lens 10 can also satisfy the relationship: 4.5mm < BFL < 10mm, where BFL is the back focal length of lens 10.

[0098] By controlling the back focal length of lens 10 to between 4.5mm and 10mm, the distance between lens 10 and direct-view chips such as micro LED display chips can be further reduced, thereby further reducing the size of the projection device 120. Furthermore, it ensures that lens 10 possesses a large aperture and a wide field of view, enabling it to work with large-area direct-view chips and improve the brightness of the projection device 120. Additionally, it guarantees the image quality of lens 10.

[0099] The specific value of the back focal length BFL of lens 10 is not limited here. The back focal length BFL of lens 10 can be 4.55mm, 4.8mm, 5mm, 5.35mm, 5.55mm, 6mm, 6.55mm, 7mm, 7.698mm, 8mm, 8.556mm, 9mm, 9.355mm, 9.55mm, etc.

[0100] In some possible implementations, the lens 10 can also satisfy the relationship: 30.02mm < R1 < 100mm, where R1 is the radius of curvature of the image side of the lens closest to the image side in the lens group 101.

[0101] In this way, by ensuring that lens 10 satisfies the relationship 30.02mm < R1 < 100mm, it is possible to simultaneously achieve a large aperture and a wide field of view while reducing the manufacturing difficulty of the lens closest to the image side, thereby improving yield and economic efficiency. Furthermore, it facilitates aberration correction and enhances the optical performance of lens 10. In addition, it prevents the image side of the lens closest to the image side from being too protruding or too flat, effectively balancing the optical performance of lens 10 with the design of the vehicle headlights.

[0102] The specific value of R1 is not restricted here. R1 can be 30.5mm, 31mm, 35mm, 40mm, 45.55mm, 50.6mm, 56.55mm, 60mm, 67.698mm, 70mm, 75.654mm, 80mm, 855mm, 90mm, etc.

[0103] In some possible implementations, lens 10 satisfies the relationship: 15mm < R2 < 30mm, where R2 is the radius of curvature of the object side surface of the lens closest to the object side in lens group 101.

[0104] In this way, by ensuring that lens 10 satisfies the relationship 15mm < R2 < 30mm, it is possible to simultaneously achieve a large aperture and a wide field of view while reducing the manufacturing difficulty of the lens closest to the object side, thereby improving yield and economic efficiency. Additionally, it also prevents the object side of the lens closest to the object side from being too protruding or too concave, effectively balancing the optical performance of lens 10 with the design of the vehicle headlights.

[0105] The specific value of R2 is not restricted here. R2 can be 15.315mm, 16mm, 16.5mm, 17mm, 17.55mm, 18mm, 19mm, 20mm, 21mm, 23.65mm, 25mm, 25.98mm, 28mm, 29.5mm, etc.

[0106] In some possible implementations, at least one lens in the lens group 101 may be an aspherical lens with optical power, for example... Figure 3 As shown, the number of aspherical mirrors in lens group 101 can be one, but of course, the number of aspherical mirrors can also be more than one.

[0107] Thus, by incorporating aspherical mirrors capable of correcting aberrations into the lens group 101, the optical performance of the lens 10 can be further improved, thereby enhancing image quality. Furthermore, the more aspherical mirrors there are, the greater the positive impact on the optical performance of the lens 10.

[0108] It should be noted that at least one of the image side and the object side of the aspherical lens can be aspherical. The more aspherical surfaces the aspherical lens has, the greater the improvement in the optical performance of the lens 10.

[0109] The specific location of the aspherical mirror is not limited here. In some embodiments, there may be two aspherical mirrors, which may be located on the second side and closest to the aperture stop 102. That is, the two aspherical mirrors are located between the aperture stop 102 and the display unit 20, and the two aspherical mirrors are the two lenses closest to the aperture stop 102 on the second side. In other embodiments, there may be only one aspherical mirror, which may be the lens closest to the image side in the lens group 101.

[0110] In some possible implementations, all lenses with optical power in lens group 101 may also be spherical lenses.

[0111] In this way, while enabling lens 10 to possess the characteristics of a large aperture and a wide field of view, the manufacturing difficulty of each lens element can be reduced, thereby lowering the cost of lens 10 and improving its economic efficiency. Furthermore, the back focal length of lens 10 can be reduced, ensuring that lens 10 can be used with a direct-viewing chip and enabling a large target surface design.

[0112] In some possible implementations, all lenses in the lens group 101 can be made of the same material; for example, all lenses in the lens group 101 can be made of optical glass or plastic.

[0113] In some possible implementations, the lens group 101 may also be composed of lenses made of at least two different materials. For example, one part of the lenses in the lens group 101 may be made of optical glass and the other part may be made of plastic.

[0114] See also some possible implementations. Figure 3 As shown, the lens 10 may also include a cover glass 103. The cover glass 103 is disposed between the lens group 101 and the display unit 20, and the cover glass 103 is used to protect the display unit 20.

[0115] In some possible implementations, the lens 10 may also include a filter (not shown) for correcting color deviation. The filter is disposed between the lens group 101 and the display unit 20.

[0116] It should be noted that the lens 10 may include one of the cover glass 103 and the filter, or the lens 10 may also include the cover glass 103 and the filter.

[0117] The projection device 120 provided in this application embodiment will be described below with reference to specific embodiments.

[0118] Example 1:

[0119] Figure 4 This is a schematic diagram of the projection device 120 provided in Embodiment 1 of this application.

[0120] See Figure 4 As shown, the projection device 120 may include a lens 10 and a display unit 20. The lens 10 includes a lens group 101, an aperture 102, and a cover glass 103. The lens group 101 includes a first lens 11, a second lens 12, a third lens 13, a fourth lens 14, and a fifth lens 15 arranged sequentially from the image side to the object side. The first lens 11 is closest to the image side, the fifth lens 15 is closest to the image side, the aperture 102 is disposed between the second lens 12 and the third lens 13, and the cover glass 103 is disposed between the fifth lens 15 and the display unit 20. All five lenses, from the first lens 11 to the fifth lens 15, can be made of optical glass or plastic. The display unit 20 can be a direct-view chip such as a Micro LED display chip, a Mini LED display chip, or a TFT display chip.

[0121] The first lens 11 has positive optical power, and the focal length of the first lens 11 is f1 = 77.326 mm.

[0122] The second lens 12 has negative optical power, and the focal length of the second lens 12 is f2 = -37.669mm.

[0123] The third lens 13 has positive power and a focal length f3 = 71.737 mm.

[0124] The fourth lens 14 has positive power and a focal length f4 = 34.732 mm.

[0125] The fifth lens 15 has positive power and a focal length f5 = 1520.703 mm.

[0126] Therefore, it can be seen that the number of lenses with optical power in lens group 101 is five, which meets the requirements. In addition, the second lens 12 has negative optical power, see [link to documentation]. Figure 4 As shown, the second lens 12 is located on the first side and is closest to the aperture stop 102, which meets the requirements.

[0127] The lens closest to the image side in lens 10 is the first lens 11. The radius of curvature R1 of the image side of the first lens 11 is 82.5151mm, which is greater than 30.02mm and less than 100mm, thus meeting the requirements.

[0128] The lens closest to the object side in lens 10 is the fifth lens 15. The radius of curvature of the object side of the fifth lens 15 is R2 = 15.87mm, which is greater than 15mm and less than 30mm, thus meeting the requirements.

[0129] The back focal length (BFL) of lens 10 is 7.25mm, which is greater than 4.5mm and less than 10mm, thus meeting the requirements.

[0130] Table 1 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment.

[0131] Surface No. Surface Type R (mm) TH (mm) Nd Vd OBJ Sphere Infinity 13000.000 S1 Sphere 82.815 5.971 1.90 31.3 S2 Sphere -467.891 13.723 S3 Sphere -28.867 1.427 1.95 17.9 S4 Sphere -143.044 0.013 S5 Sphere Infinity 0.649 S6 Asphere 244.890 15.075 1.54 56 S7 Asphere -45.040 0.065 S8 Asphere 29.764 23.355 1.54 56 S9 Asphere -36.784 0.130 S10 Sphere 20.806 10.992 1.88 40.8 S11 Sphere 15.870 5.294 S12 Sphere Infinity 1.102 1.52 58.6 S13 Sphere Infinity 0.696 ImgH Sphere Infinity 0.00E+00

[0132] Wherein, S1 is the image-side surface of the first lens 11, and S2 is the object-side surface of the first lens 11. S3 is the image-side surface of the second lens 12, and S4 is the object-side surface of the second lens 12. S5 is the aperture stop 102. S6 is the image-side surface of the third lens 13, and S7 is the object-side surface of the third lens 13. S8 is the image-side surface of the fourth lens 14, and S9 is the object-side surface of the fourth lens 14. S10 is the image-side surface of the fifth lens 15, and S11 is the object-side surface of the fifth lens 15. S12 is the image-side surface of the cover glass 103, and S13 is the object-side surface of the cover glass 103. OBJ is the projection surface, and ImgH is the imaging surface.

[0133] R is the radius of curvature of the optical element (such as a lens or glass cover) at the corresponding position on the optical axis, Th is the surface thickness of the optical element in the direction of 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.

[0134] Table 2 shows the aspheric coefficients of each order in this embodiment.

[0135] Surface 4th order coefficient 6th order coefficient 8th order coefficient 10th order coefficient 12th order coefficient 14th order coefficient 16th order coefficient S6 -1.8721E-06 6.2472E-09 -2.4486E-11 5.0950E-14 -7.8118E-17 9.8073E-20 -6.0972E-23 S7 1.2105E-05 -3.4080E-08 8.4654E-11 -1.5377E-13 2.0330E-16 -1.4905E-19 3.6352E-23 S8 -7.0386E-05 1.7231E-07 -2.3704E-10 1.4072E-13 0.0000E+00 0.0000E+00 0.0000E+00 S9 -4.1095E-05 2.1503E-07 -4.5079E-10 3.8955E-13 0.0000E+00 0.0000E+00 0.0000E+00

[0136] As shown in Table 2, the third lens element 13 and the fourth lens element 14 in lens 10 are both aspherical lenses, meaning that lens 10 contains four aspherical surfaces. The aspherical surface shape z of each aspherical lens can be calculated using the following aspherical formula:

[0137]

[0138] Where z is the aspherical elevation, r is the radial coordinate of the aspherical surface, c is the spherical curvature at the vertex of the aspherical surface, k is the quadratic surface constant, and A4, A6, A8, ..., A30 are aspherical coefficients. Additionally, Ai corresponds to the i-th order coefficients in Table 2; for example, A4 corresponds to the 4th order coefficients in Table 2.

[0139] It should be noted that the aspherical surface shape z of a spherical mirror can also be calculated using other aspherical formulas, which will not be elaborated here.

[0140] Table 3 shows the optical parameters of the lens 10 provided in this embodiment.

[0141]

[0142]

[0143] As shown in Table 3, the lens 10 provided in Embodiment 1 of this application has the characteristics of large aperture and large field of view, and has a small back focal length.

[0144] Wherein, Fno is the aperture of lens 10, BFL is the back focal length of lens 10, TTL is the total optical length of lens 10, R1 is the radius of curvature of the image side of the lens closest to the image side of lens 10, R2 is the radius of curvature of the object side of the lens closest to the object side of lens 10, f1 is the focal length of the first lens 11, f2 is the focal length of the second lens 12, f3 is the focal length of the third lens 13, f4 is the focal length of the fourth lens 14, and f5 is the focal length of the fifth lens 15.

[0145] Figure 5 for Figure 4 The spherical chromatic aberration diagram of lens 10. Figure 5 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 5 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 lens 10 in this embodiment. From... Figure 5 As can be seen, in this embodiment, axial aberration is controlled within a very small range, resulting in good correction.

[0146] Figure 6 for Figure 4 The image of shot 10 in the scene is a fade-out curve. Figure 7 for Figure 4 The distortion image of lens 10 in the image. Figure 6 In the diagram, S represents the field curvature of light with a wavelength of 525 nm in the meridional image plane, and T represents the field curvature of light with a wavelength of 525 nm in the sagittal image plane. Figure 7 In the image, the solid line represents the distortion value of light with a center wavelength of 525nm passing through the lens 10 of this embodiment. In this embodiment, combined with... Figure 6 and Figure 7 It can be seen that the lens 10 provided in this embodiment controls field curvature and distortion within the corresponding range, and has high imaging quality.

[0147] Example 2:

[0148] Figure 8 This is a schematic diagram of the projection device 120 provided in Embodiment 2 of this application.

[0149] See Figure 8 As shown, the projection device 120 may include a lens 10 and a display unit 20. The lens 10 includes a lens group 101, an aperture 102, and a cover glass 103. The lens group 101 includes a first lens 11, a second lens 12, a third lens 13, a fourth lens 14, and a fifth lens 15 arranged sequentially from the image side to the object side. The first lens 11 is closest to the image side, the fifth lens 15 is closest to the image side, the aperture 102 is disposed between the second lens 12 and the third lens 13, and the cover glass 103 is disposed between the fifth lens 15 and the display unit 20. All five lenses, from the first lens 11 to the fifth lens 15, can be made of optical glass or plastic. The display unit 20 can be a direct-view chip such as a Micro LED display chip, a Mini LED display chip, or a TFT display chip.

[0150] The first lens 11 has positive optical power, and the focal length of the first lens 11 is f1 = 46.801 mm.

[0151] The second lens 12 has negative optical power, and the focal length of the second lens 12 is f2 = -40.389mm.

[0152] The third lens 13 has positive power and a focal length f3 = 41.173 mm.

[0153] The fourth lens 14 has positive power and a focal length f4 = 45.964 mm.

[0154] The fifth lens 15 has positive power and a focal length f5 = 357.239 mm.

[0155] Therefore, it can be seen that the number of lenses with optical power in lens group 101 is five, which meets the requirements. In addition, the second lens 12 has negative optical power, see [link to documentation]. Figure 8 As shown, the second lens 12 is located on the first side and is closest to the aperture stop 102, which meets the requirements.

[0156] The lens closest to the image side in lens 10 is the first lens 11. The radius of curvature R1 of the image side of the first lens 11 is 40.865mm, which is greater than 30.02mm and less than 100mm, thus meeting the requirements.

[0157] The lens closest to the object side in lens 10 is the fifth lens 15. The radius of curvature of the object side of the fifth lens 15 is R2 = 15.391mm, which is greater than 15mm and less than 30mm, thus meeting the requirements.

[0158] The back focal length (BFL) of lens 10 is 5.620mm, which is greater than 4.5mm and less than 10mm, thus meeting the requirements.

[0159] Table 4 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment 2.

[0160]

[0161]

[0162] Wherein, S1 is the image-side surface of the first lens 11, and S2 is the object-side surface of the first lens 11. S3 is the image-side surface of the second lens 12, and S4 is the object-side surface of the second lens 12. S5 is the aperture stop 102. S6 is the image-side surface of the third lens 13, and S7 is the object-side surface of the third lens 13. S8 is the image-side surface of the fourth lens 14, and S9 is the object-side surface of the fourth lens 14. S10 is the image-side surface of the fifth lens 15, and S11 is the object-side surface of the fifth lens 15. S12 is the image-side surface of the cover glass 103, and S13 is the object-side surface of the cover glass 103. OBJ is the projection surface, and ImgH is the imaging surface.

[0163] R is the radius of curvature of the optical element (such as a lens or glass cover) at the corresponding position on the optical axis, Th is the surface thickness of the optical element in the direction of 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.

[0164] Table 5 shows the aspheric coefficients of each order in this embodiment 2.

[0165] Surface 4th order coefficient 6th order coefficient 8th order coefficient 10th order coefficient 12th order coefficient 14th order coefficient S1 -3.02E-07 2.30E-09 -9.02E-12 -5.82E-14 1.66E-16 -1.32E-19 S2 -1.91E-06 9.21E-09 -4.98E-11 1.29E-13 -1.69E-16 9.45E-20

[0166] As shown in Table 5, the first lens element 11 in lens 10 is an aspherical lens, meaning that lens 10 includes two aspherical surfaces. The aspherical surface shape z of the first lens element 11 can be calculated using the following aspherical formula:

[0167]

[0168] Where z is the aspherical elevation, r is the radial coordinate of the aspherical surface, c is the spherical curvature at the vertex of the aspherical surface, k is the quadratic surface constant, and A4, A6, A8, ..., A30 are aspherical coefficients. Additionally, Ai corresponds to the i-th order coefficients in Table 2; for example, A4 corresponds to the 4th order coefficients in Table 2.

[0169] It should be noted that the aspherical surface shape z of a spherical mirror can also be calculated using other aspherical formulas, which will not be elaborated here.

[0170] Table 6 shows the optical parameters of the lens 10 provided in this embodiment 2.

[0171] f1 (mm) 46.801 R1 (mm) 40.865 f2 (mm) -40.389 R2 (mm) 15.391 f3 (mm) 43.173 TTL (mm) 58.699 f4 (mm) 45.964 BFL (mm) 5.620 f5 (mm) 357.239 Fno 0.608

[0172] As shown in Table 6, the lens 10 provided in Embodiment 2 of this application has the characteristics of large aperture and large field of view, and has a small back focal length.

[0173] Wherein, Fno is the aperture of lens 10, BFL is the back focal length of lens 10, TTL is the total optical length of lens 10, R1 is the radius of curvature of the image side of the lens closest to the image side of lens 10, R2 is the radius of curvature of the object side of the lens closest to the object side of lens 10, f1 is the focal length of the first lens 11, f2 is the focal length of the second lens 12, f3 is the focal length of the third lens 13, f4 is the focal length of the fourth lens 14, and f5 is the focal length of the fifth lens 15.

[0174] Figure 9 for Figure 8 The spherical chromatic aberration diagram of lens 10. Figure 9 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 9 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 lens 10 in this embodiment. From... Figure 9 As can be seen, in this embodiment, axial aberration is controlled within a very small range, resulting in good correction.

[0175] Figure 10 for Figure 8 The image of shot 10 in the scene is a fade-out curve. Figure 11 for Figure 8 The distortion image of lens 10 in the image. Figure 10 In the diagram, S represents the field curvature of light with a wavelength of 525 nm in the meridional image plane, and T represents the field curvature of light with a wavelength of 525 nm in the sagittal image plane. Figure 11 In the image, the solid line represents the distortion value of light with a center wavelength of 525nm passing through the lens 10 of this embodiment. In this embodiment, combined with... Figure 10 and Figure 11 It can be seen that the lens 10 provided in this embodiment controls field curvature and distortion within the corresponding range, and has high imaging quality.

[0176] Example 3:

[0177] Figure 12 This is a schematic diagram of the projection device 120 provided in Embodiment 3 of this application.

[0178] See Figure 12 As shown, the projection device 120 may include a lens 10 and a display unit 20. The lens 10 includes a lens group 101, an aperture 102, and a cover glass 103. The lens group 101 includes a first lens 11, a second lens 12, a third lens 13, a fourth lens 14, and a fifth lens 15 arranged sequentially from the image side to the object side. The first lens 11 is closest to the image side, the fifth lens 15 is closest to the image side, the aperture 102 is disposed between the second lens 12 and the third lens 13, and the cover glass 103 is disposed between the fifth lens 15 and the display unit 20. All five lenses, from the first lens 11 to the fifth lens 15, can be made of optical glass or plastic. The display unit 20 can be a direct-view chip such as a Micro LED display chip, a Mini LED display chip, or a TFT display chip.

[0179] The first lens 11 has positive power and a focal length f1 = 53.949 mm.

[0180] The second lens 12 has negative optical power, and the focal length of the second lens 12 is f2 = -30.622mm.

[0181] The third lens 13 has positive power and a focal length f3 = 46.543 mm.

[0182] The fourth lens 14 has positive power and a focal length f4 = 46.857 mm.

[0183] The fifth lens 15 has positive power and a focal length f5 = 181.938 mm.

[0184] Therefore, it can be seen that the number of lenses with optical power in lens group 101 is five, which meets the requirements. In addition, the second lens 12 has negative optical power, see [link to documentation]. Figure 12 As shown, the second lens 12 is located on the first side and is closest to the aperture stop 102, which meets the requirements.

[0185] The lens closest to the image side in lens 10 is the first lens 11. The radius of curvature R1 of the image side of the first lens 11 is 45.505mm, which is greater than 30.02mm and less than 100mm, thus meeting the requirements.

[0186] The lens closest to the object side in lens 10 is the fifth lens 15. The radius of curvature of the object side of the fifth lens 15 is R2 = 21.501mm, which is greater than 15mm and less than 30mm, thus meeting the requirements.

[0187] The back focal length (BFL) of lens 10 is 8.869mm, which is greater than 4.5mm and less than 10mm, thus meeting the requirements.

[0188] Table 7 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment 3.

[0189] Surface No. Surface Type R (mm) TH (mm) Nd Vd OBJ Sphere Infinity 12975.000 S1 Asphere 45.505 8.640 1.58 27.6 S2 Asphere -99.840 11.878 S3 Sphere -31.617 1.427 1.95 17.9 S4 Sphere 470.271 0.639 S5 Sphere Infinity 0.649 S6 Sphere -465.074 14.046 1.82 46.6 S7 Sphere -35.860 0.065 S8 Sphere 74.478 11.558 1.88 40.8 S9 Sphere -88.112 0.130 S10 Sphere 23.843 11.678 1.88 40.8 S11 Sphere 21.501 5.732 S12 Sphere Infinity 1.102 1.52 58.6 S13 Sphere Infinity 1.919 ImgH Sphere Infinity 0.00E+00

[0190] Wherein, S1 is the image-side surface of the first lens 11, and S2 is the object-side surface of the first lens 11. S3 is the image-side surface of the second lens 12, and S4 is the object-side surface of the second lens 12. S5 is the aperture stop 102. S6 is the image-side surface of the third lens 13, and S7 is the object-side surface of the third lens 13. S8 is the image-side surface of the fourth lens 14, and S9 is the object-side surface of the fourth lens 14. S10 is the image-side surface of the fifth lens 15, and S11 is the object-side surface of the fifth lens 15. S12 is the image-side surface of the cover glass 103, and S13 is the object-side surface of the cover glass 103. OBJ is the projection surface, and ImgH is the imaging surface.

[0191] R is the radius of curvature of the optical element (such as a lens or glass cover) at the corresponding position on the optical axis, Th is the surface thickness of the optical element in the direction of 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.

[0192] Table 8 shows the aspheric coefficients of each order in this embodiment 3.

[0193] Surface Conic coefficient 4th order coefficient 6th order coefficient 8th order coefficient 10th order coefficient S1 -6.22E+00 4.50E-06 -1.05E-08 -4.42E-12 4.73E-15 S2 -1.56E+02 -1.30E-05 3.85E-08 -7.68E-11 6.17E-14

[0194] As shown in Table 8, the first lens element 11 in lens 10 is an aspherical lens, meaning that lens 10 includes two aspherical surfaces. The aspherical surface shape z of the first lens element 11 can be calculated using the following aspherical formula:

[0195]

[0196] Where z is the aspherical elevation, r is the radial coordinate of the aspherical surface, c is the spherical curvature at the vertex of the aspherical surface, k is the quadratic surface constant, and A4, A6, A8, ... A30 are aspherical coefficients. Additionally, Ai corresponds to the i-th order coefficients in Table 2; for example, A4 corresponds to the 4th order coefficients in Table 2. The Conic coefficient refers to k, which is the quadratic surface constant.

[0197] It should be noted that the aspherical surface shape z of a spherical mirror can also be calculated using other aspherical formulas, which will not be elaborated here.

[0198] Table 9 shows the optical parameters of the lens 10 provided in this embodiment 3.

[0199] f1 (mm) 53.949 R1 (mm) 45.505 f2 (mm) -30.622 R2 (mm) 21.501 f3 (mm) 46.543 TTL (mm) 69.578 f4 (mm) 46.857 BFL (mm) 8.869 f5 (mm) 181.938 Fno 0.637

[0200] As shown in Table 9, the lens 10 provided in Embodiment 3 of this application has the characteristics of large aperture and large field of view, and has a small back focal length.

[0201] Wherein, Fno is the aperture of lens 10, BFL is the back focal length of lens 10, TTL is the total optical length of lens 10, R1 is the radius of curvature of the image side of the lens closest to the image side of lens 10, R2 is the radius of curvature of the object side of the lens closest to the object side of lens 10, f1 is the focal length of the first lens 11, f2 is the focal length of the second lens 12, f3 is the focal length of the third lens 13, f4 is the focal length of the fourth lens 14, and f5 is the focal length of the fifth lens 15.

[0202] Figure 13 for Figure 12 The spherical chromatic aberration diagram of lens 10. Figure 13 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 13 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 lens 10 in this embodiment. From... Figure 13 As can be seen, in this embodiment, axial aberration is controlled within a very small range, resulting in good correction.

[0203] Figure 14 for Figure 12 The image of shot 10 in the scene is a fade-out curve. Figure 15 for Figure 12 The distortion image of lens 10 in the image. Figure 14 In the diagram, S represents the field curvature of light with a wavelength of 525 nm in the meridional image plane, and T represents the field curvature of light with a wavelength of 525 nm in the sagittal image plane. Figure 15In the image, the solid line represents the distortion value of light with a center wavelength of 525nm passing through the lens 10 of this embodiment. In this embodiment, combined with... Figure 14 and Figure 15 It can be seen that the lens 10 provided in this embodiment controls field curvature and distortion within the corresponding range, and has high imaging quality.

[0204] Example 4:

[0205] Figure 16 This is a schematic diagram of the projection device 120 provided in Embodiment 4 of this application.

[0206] See Figure 16 As shown, the projection device 120 may include a lens 10 and a display unit 20. The lens 10 includes a lens group 101, an aperture 102, and a cover glass 103. The lens group 101 includes a first lens 11, a second lens 12, a third lens 13, a fourth lens 14, and a fifth lens 15 arranged sequentially from the image side to the object side. The first lens 11 is closest to the image side, the fifth lens 15 is closest to the image side, the aperture 102 is disposed between the second lens 12 and the third lens 13, and the cover glass 103 is disposed between the fifth lens 15 and the display unit 20. All five lenses, from the first lens 11 to the fifth lens 15, can be made of optical glass or plastic. The display unit 20 can be a direct-view chip such as a Micro LED display chip, a Mini LED display chip, or a TFT display chip.

[0207] The first lens 11 has positive optical power, and the focal length of the first lens 11 is f1 = 46.620 mm.

[0208] The second lens 12 has negative optical power, and the focal length of the second lens 12 is f2 = -39.654mm.

[0209] The third lens 13 has positive power and a focal length f3 = 62.501 mm.

[0210] The fourth lens 14 has positive power and a focal length f4 = 64.770 mm.

[0211] The fifth lens 15 has positive power and a focal length f5 = 58.035 mm.

[0212] Therefore, it can be seen that the number of lenses with optical power in lens group 101 is five, which meets the requirements. In addition, the second lens 12 has negative optical power, see [link to documentation]. Figure 16 As shown, the second lens 12 is located on the first side and is closest to the aperture stop 102, which meets the requirements.

[0213] The lens closest to the image side in lens 10 is the first lens 11. The radius of curvature R1 of the image side of the first lens 11 is 49.097mm, which is greater than 30.02mm and less than 100mm, thus meeting the requirements.

[0214] The lens closest to the object side in lens 10 is the fifth lens 15. The radius of curvature of the object side of the fifth lens 15 is R2 = 39.260mm, which is greater than 15mm and less than 30mm, thus meeting the requirements.

[0215] The back focal length (BFL) of lens 10 is 5.190mm, which is greater than 4.5mm and less than 10mm, thus meeting the requirements.

[0216] Table 10 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment 4.

[0217] Surface No. Surface Type R (mm) TH (mm) Nd Vd OBJ Sphere Infinity 12975.000 S1 Sphere 49.097 8.093 2.0 28.3 S2 Sphere -1261.038 8.194 S3 Sphere -36.701 1.427 1.95 17.9 S4 Sphere -890.467 0.013 S5 Sphere Infinity 6.592 S6 Sphere -109.979 7.474 1.82 46.6 S7 Sphere -36.112 0.065 S8 Sphere 29.167 7.712 1.82 46.5 S9 Sphere 56.751 5.192 S10 Sphere 25.447 11.678 1.88 40.8 S11 Sphere 39.260 3.906 S12 Sphere Infinity 1.102 1.52 58.6 S13 Sphere Infinity 0.066 ImgH Sphere Infinity 0.00E+00

[0218] As shown in Table 10, all the lenses in lens 10 are spherical lenses.

[0219] S1 is the image-side surface of the first lens 11, and S2 is the object-side surface of the first lens 11. S3 is the image-side surface of the second lens 12, and S4 is the object-side surface of the second lens 12. S5 is the aperture stop 102. S6 is the image-side surface of the third lens 13, and S7 is the object-side surface of the third lens 13. S8 is the image-side surface of the fourth lens 14, and S9 is the object-side surface of the fourth lens 14. S10 is the image-side surface of the fifth lens 15, and S11 is the object-side surface of the fifth lens 15. S12 is the image-side surface of the cover glass 103, and S13 is the object-side surface of the cover glass 103. OBJ is the projection surface, and ImgH is the imaging surface.

[0220] R is the radius of curvature of the optical element (such as a lens or glass cover) at the corresponding position on the optical axis, Th is the surface thickness of the optical element in the direction of 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.

[0221] Table 11 shows the optical parameters of the lens 10 provided in this embodiment 4.

[0222] f1 (mm) 46.620 R1 (mm) 49.097 f2 (mm) -39.654 R2 (mm) 39.260 f3 (mm) 62.501 TTL (mm) 61.630 f4 (mm) 64.770 BFL (mm) 5.190 f5 (mm) 58.035 Fno 0.469

[0223] As shown in Table 11, the lens 10 provided in Embodiment 4 of this application has the characteristics of large aperture and large field of view, and has a small back focal length.

[0224] Wherein, Fno is the aperture of lens 10, BFL is the back focal length of lens 10, TTL is the total optical length of lens 10, R1 is the radius of curvature of the image side of the lens closest to the image side of lens 10, R2 is the radius of curvature of the object side of the lens closest to the object side of lens 10, f1 is the focal length of the first lens 11, f2 is the focal length of the second lens 12, f3 is the focal length of the third lens 13, f4 is the focal length of the fourth lens 14, and f5 is the focal length of the fifth lens 15.

[0225] Figure 17 for Figure 16 The spherical chromatic aberration diagram of lens 10. Figure 17 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 17 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 lens 10 in this embodiment. From... Figure 17 As can be seen, in this embodiment, axial aberration is controlled within a very small range, resulting in good correction.

[0226] Figure 18 for Figure 16 The image of shot 10 in the scene is a fade-out curve. Figure 19 for Figure 16 The distortion image of lens 10 in the image. Figure 18 In the diagram, S represents the field curvature of light with a wavelength of 525 nm in the meridional image plane, and T represents the field curvature of light with a wavelength of 525 nm in the sagittal image plane. Figure 19 In the image, the solid line represents the distortion value of light with a center wavelength of 525nm passing through the lens 10 of this embodiment. In this embodiment, combined with... Figure 18 and Figure 19 It can be seen that the lens 10 provided in this embodiment controls field curvature and distortion within the corresponding range, and has high imaging quality.

[0227] 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 communication 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.

[0228] The devices or elements referred to in the embodiments of this application or implied herein must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as limiting the embodiments of this application. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise precisely specified.

[0229] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the present application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0230] The term "multiple" in this article refers to two or more. The term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Furthermore, the character " / " in this article generally indicates an "or" relationship between the preceding and following related objects; in formulas, the character " / " indicates a "division" relationship between the preceding and following related objects.

[0231] It is understood that the various numerical designations used in the embodiments of this application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application.

[0232] It is understood that, in the embodiments of this application, the order of the above-mentioned process numbers does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

Claims

1. A lens, characterized in that, Includes lens group and aperture stop; The lens group includes at least five lenses arranged from the image side to the object side, wherein the number of lenses having optical power in the lens group is at least five, and the number of lenses having negative optical power in the lens group is at least one. The aperture stop includes a first side and a second side disposed opposite to each other along the direction from the image side to the object side, the first side being closer to the image side and the second side being closer to the object side, and at least one of the first side and the second side is provided with the lens, wherein: When the lens is disposed on the first side, the lens located on the first side and closest to the aperture stop has negative optical power; and / or, When the lens is provided on the second side, the lens located on the second side and closest to the aperture has negative power.

2. The lens according to claim 1, characterized in that, The lens satisfies the following relationship: 4.5mm < BFL < 10mm, where BFL is the back focal length of the lens.

3. The lens according to claim 1 or 2, characterized in that, The lens satisfies the following relationship: 30.02mm < R1 < 100mm, where R1 is the radius of curvature of the image side of the lens closest to the image side in the lens group.

4. The lens according to any one of claims 1 to 3, characterized in that, The lens satisfies the following relationship: 15mm < R2 < 30mm, where R2 is the radius of curvature of the object side surface of the lens closest to the object side in the lens group.

5. The lens according to any one of claims 1 to 4, characterized in that, The lens is provided on both the first side and the second side.

6. The lens according to any one of claims 1 to 5, characterized in that, At least one of the lenses in the lens group is an aspherical lens with optical power.

7. The lens according to any one of claims 1 to 5, characterized in that, All lenses with optical power in the lens group are spherical lenses.

8. The lens according to any one of claims 1 to 7, characterized in that, The number of lenses with negative optical power in the lens group is one.

9. A projection device, characterized in that, Includes a display unit and a lens as described in any one of claims 1 to 8; The display surface of the display unit is opposite to the lens closest to the object side of the lens. The display unit is configured to form a display image and transmit the display image to the lens via the display surface.

10. The projection device according to claim 9, characterized in that, The display unit is a micro LED display chip, a sub-millimeter LED display chip, or a thin-film field-effect transistor display chip.

11. A vehicle lighting device, characterized in that, It includes a housing and a projection device as described in claim 9 or 10, wherein at least a portion of the projection device is disposed inside the housing.

12. A means of transportation, characterized in that, Includes the vehicle lighting device as described in claim 11.

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