WO2026007666A1 - 镜头、投影装置、车灯装置和交通工具 - Google Patents

镜头、投影装置、车灯装置和交通工具

Info

Publication number
WO2026007666A1
WO2026007666A1 PCT/CN2025/100765 CN2025100765W WO2026007666A1 WO 2026007666 A1 WO2026007666 A1 WO 2026007666A1 CN 2025100765 W CN2025100765 W CN 2025100765W WO 2026007666 A1 WO2026007666 A1 WO 2026007666A1
Authority
WO
WIPO (PCT)
Prior art keywords
lens
image
lenses
closest
optical power
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/CN2025/100765
Other languages
English (en)
French (fr)
Inventor
马明
赵壮
苏喜林
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shenzhen Yinwang Intelligent Technology Co Ltd
Original Assignee
Shenzhen Yinwang Intelligent Technology Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shenzhen Yinwang Intelligent Technology Co Ltd filed Critical Shenzhen Yinwang Intelligent Technology Co Ltd
Publication of WO2026007666A1 publication Critical patent/WO2026007666A1/zh
Pending legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21S—NON-PORTABLE LIGHTING DEVICES; SYSTEMS THEREOF; VEHICLE LIGHTING DEVICES SPECIALLY ADAPTED FOR VEHICLE EXTERIORS
    • F21S43/00—Signalling devices specially adapted for vehicle exteriors, e.g. brake lamps, direction indicator lights or reversing lights
    • F21S43/20—Signalling devices specially adapted for vehicle exteriors, e.g. brake lamps, direction indicator lights or reversing lights characterised by refractors, transparent cover plates, light guides or filters
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G02B13/06—Panoramic objectives; So-called "sky lenses" including panoramic objectives having reflecting surfaces
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G02B13/18—Optical objectives specially designed for the purposes specified below with lenses having one or more non-spherical faces, e.g. for reducing geometrical aberration
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
    • G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
    • G09F9/30—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements
    • G09F9/33—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements being semiconductor devices, e.g. diodes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21W—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO USES OR APPLICATIONS OF LIGHTING DEVICES OR SYSTEMS
    • F21W2103/00—Exterior vehicle lighting devices for signalling purposes
    • F21W2103/60—Projection of signs from lighting devices, e.g. symbols or information being projected onto the road
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F21—LIGHTING
    • F21W—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO USES OR APPLICATIONS OF LIGHTING DEVICES OR SYSTEMS
    • F21W2107/00—Use or application of lighting devices on or in particular types of vehicles
    • F21W2107/10—Use or application of lighting devices on or in particular types of vehicles for land vehicles

Definitions

  • This application relates to the field of optical technology, and in particular to a lens, a projection device, a vehicle lighting device, and a vehicle.
  • a headlight assembly comprising a lens, a modulator, a light source, and a curved mirror.
  • the curved mirror reflects the light beam emitted by the light source to the modulator, which is a liquid crystal on silicon (LCOS).
  • the modulator modulates the beam from the curved mirror to create an image beam and then projects it onto the lens.
  • the lens requires a long back focal length, resulting in a large headlight assembly and increasing the difficulty of its placement within a vehicle.
  • This application provides a lens, a projection device, a vehicle lighting device, and a vehicle.
  • the lens has a small back focal length, which can be used with direct display chips such as micro light-emitting diode display chips to form a small projection device, thereby reducing the size of the vehicle lighting device and thus reducing the difficulty of arranging the vehicle lighting device in the vehicle.
  • This application provides a lens comprising a lens group and an aperture stop.
  • the lens group includes at least five lenses arranged from the image side to the object side, wherein at least five lenses in the lens group have optical power, and at least one lens in the lens group has negative optical power.
  • 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.
  • At least one of the first side and the second side has a lens disposed thereon, wherein: when a 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 a lens is disposed on the second side, the lens located on the second side and closest to the aperture stop has negative optical power.
  • the lens provided in this application 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 systems, this reduces the size of the lighting system and simplifies 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 lens design, increasing the light-emitting area and thus improving the projection device's luminous power and brightness. Additionally, it enhances the lens's optical performance, improving image quality and reducing distortion.
  • the lens satisfies the relationship: 4.5mm ⁇ BFL ⁇ 10mm, where BFL is the back focal length of the lens.
  • the lens's back focal length between 4.5mm and 10mm, the distance between the lens and the direct-viewing chip, such as the micro LED display chip, can be further reduced, thus further reducing the size of the projection device. Furthermore, this ensures the lens possesses the characteristics of a large aperture and a wide field of view.
  • the lens satisfies 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.
  • the lens By ensuring the lens satisfies the relationship 30.02mm ⁇ R1 ⁇ 100mm, it's possible to achieve both a large aperture and a wide field of view while reducing the manufacturing difficulty of the lens element closest to the image side, thus improving yield and cost-effectiveness. Furthermore, it facilitates aberration correction and enhances the lens's optical performance. In addition, it prevents the image side of the lens element from being too prominent or too flat, effectively balancing the lens's optical performance with the headlight design.
  • 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.
  • the lens By ensuring the lens satisfies the relationship 15mm ⁇ R2 ⁇ 30mm, it's possible to achieve both a large aperture and a wide field of view while reducing the manufacturing difficulty of the lens element closest to the object side, thus improving yield and cost-effectiveness. Furthermore, it avoids the object side of the lens element being too prominent or too concave, effectively balancing the lens's optical performance with the headlight design.
  • lenses are provided on both the first and second sides.
  • the size of the lens can be further reduced, and the lens economy can be improved.
  • At least one lens in the lens group is an aspherical lens with optical power.
  • the optical performance of the lens can be further improved, thus enhancing image quality.
  • the lens group contains one lens with negative optical power.
  • a second aspect of this application provides a projection device including a display unit and a lens as described in any of the first aspects.
  • the display surface of the display unit faces the lens closest to the object side of the lens, and the display unit is configured to form a display image and transmit the display image through the display surface to the lens.
  • the lens can be used with display units of at least tens of thousands of pixels. This not only reduces the size of the projection device but also improves its brightness. Furthermore, it simplifies the structure of the projection device and enhances its performance.
  • the display unit is a micro LED display chip, a sub-millimeter LED display chip, or a thin-film field-effect transistor display chip.
  • the display unit uses an array of light sources such as micro LEDs and sub-millimeter LEDs integrated with a display chip, which simplifies the structure of the projection device and can also reduce the size of the projection device.
  • a third aspect of this application provides a vehicle lighting device, which includes a housing and a projection device as described in any of the second aspects, wherein at least a portion of the projection device is disposed inside the housing.
  • the fourth aspect of this application provides a means of transportation that includes the lighting device as described in the third aspect.
  • Figure 1 is a structural schematic diagram of a vehicle lighting device provided in the related art
  • FIG. 2 is a structural schematic diagram of a vehicle lighting device provided in an embodiment of this application.
  • Figure 3 is a schematic diagram of the structure of a lens provided in an embodiment of this application.
  • Figure 4 is a schematic diagram of the projection device provided in Embodiment 1 of this application.
  • Figure 5 shows the spherical chromatic aberration of the lens in Figure 4.
  • Figure 6 is the image bokeh curve of the lens in Figure 4.
  • Figure 7 shows the distortion diagram of the lens in Figure 4.
  • Figure 8 is a schematic diagram of the projection device provided in Embodiment 2 of this application.
  • Figure 9 shows the spherical chromatic aberration of the lens in Figure 8.
  • Figure 10 is a bokeh curve of the lens in Figure 8.
  • Figure 11 shows the distortion of the lens in Figure 8.
  • Figure 12 is a schematic diagram of the projection device provided in Embodiment 3 of this application.
  • Figure 13 is a spherical chromatic aberration diagram of the lens in Figure 12;
  • Figure 14 is the image bokeh curve of the lens in Figure 12;
  • Figure 15 shows the distortion of the lens in Figure 12
  • Figure 17 is a spherical chromatic aberration diagram of the lens in Figure 16;
  • Figure 18 is a bokeh curve of the lens in Figure 16;
  • Figure 19 shows the distortion of the lens in Figure 16.
  • 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.
  • 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.
  • 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.
  • Total track length refers to the total length from the vertex of the first lens element located on the object side of the lens to the image plane of the lens; it is also known as the total optical length.
  • Back focal length is defined as the distance from the lens element closest to the imaging plane to the display unit.
  • Optical power is the ability of a lens to refract a parallel beam of light incident from an incident lens.
  • Positive focal length means that the lens has a positive focal length and has the effect of converging light.
  • Negative power means that the lens has a negative focal length, which has the effect of diverging light.
  • 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.
  • 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.
  • CG Cover glass
  • 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.
  • the field of view is the angle between the two edges of the lens, which represent the maximum area of the image that can be seen through the lens.
  • 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.
  • 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, so the images of different colors of light cannot be perfectly superimposed during the final imaging, causing polychromatic light to scatter and form chromatic dispersion.
  • 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.
  • Figure 1 is a structural schematic diagram of a vehicle lighting device provided in the related art.
  • 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.
  • LCOS liquid crystal on silicon
  • 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.
  • the large number of components in the vehicle lighting device leads to its complex structure.
  • the complex optical path within the vehicle lighting device results in low illumination efficiency.
  • 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.
  • 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.
  • 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.
  • 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.
  • vehicle 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.
  • the following explanation uses “car” as an example of the aforementioned means of transportation.
  • 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.
  • 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.
  • 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.
  • FIG. 2 is a structural schematic diagram of a vehicle lighting device 100 provided in an embodiment of this application.
  • 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, as shown in Figure 2, the projection device 120 is disposed inside the housing 110. Alternatively, the projection device 120 may be partially disposed inside the housing 110 and partially disposed outside the housing 110. The projection device 120 is used to fulfill the lighting and other display requirements of the vehicle lighting device 100.
  • 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.
  • HUD head-up display
  • AR augmented reality
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • Figure 3 is a schematic diagram of the structure of a lens 10 provided in an embodiment of this application.
  • 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.
  • the lens group 101 includes five lenses: 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.
  • the number of lenses in the lens group 101 may exceed five.
  • the lens group 101 has at least five lenses with optical power.
  • the lens group 101 has five lenses with optical power.
  • the number of lenses with optical power in the lens group 101 may exceed five.
  • the lens group 101 has at least one lens with negative optical power.
  • the lens group 101 has one lens with negative optical power.
  • the lens group 101 may have more than one lens with negative optical power.
  • 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
  • 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.
  • the lens located on the first side and closest to the aperture stop 102 has negative optical power.
  • the lens located on the second side and closest to the aperture stop 102 has negative optical power.
  • the lens with negative optical power can be located on either the first side or the second side and is 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 are respectively disposed closest to the aperture stop 102, i.e., the aperture stop 102 is located between the two lenses with negative optical power.
  • the negative optical power of the lens contributes negatively to the optical power of the lens 10.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • the optical performance of the lens 10 can be improved, thereby improving image quality and reducing distortion.
  • the lens 10 in addition to being constructed by at least five lenses with optical power (for example, the lens 10 in Figure 3 is composed of five lenses with optical power), the lens 10 can also be constructed by a portion of lenses with optical power and a portion of lenses without optical power.
  • the lens 10 may include five lenses with optical power and two lenses without optical power.
  • 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.
  • 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.
  • the number of lenses with negative optical power in the lens group 101 can be one, as shown in FIG3.
  • the lens with negative optical power can be located on the first side or the second side and is set closest to the aperture stop 102.
  • lens 10 can also satisfy the relationship: 4.5mm ⁇ BFL ⁇ 10mm, where BFL is the back focal length of lens 10.
  • lens 10 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.
  • 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.
  • 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.
  • 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.
  • R1 can be 30.5mm, 31mm, 35mm, 40mm, 45.55mm, 50.6mm, 56.55mm, 60mm, 67.698mm, 70mm, 75.654mm, 80mm, 855mm, 90mm, etc.
  • 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.
  • 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.
  • R2 can be 15.315mm, 16mm, 16.5mm, 17mm, 17.55mm, 18mm, 19mm, 20mm, 21mm, 23.65mm, 25mm, 25.98mm, 28mm, 29.5mm, etc.
  • At least one lens in the lens group 101 can be an aspherical lens with optical power, as shown in Figure 3.
  • the number of aspherical lenses in the lens group 101 can be one, or more than one.
  • 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.
  • At least one of the image side and the object side of the aspherical lens can be aspherical.
  • the specific location of the aspherical mirror is not limited here.
  • all lenses with optical power in lens group 101 may also be spherical lenses.
  • lens 10 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.
  • 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.
  • the lens group 101 may also be composed of lenses made of at least two different materials.
  • 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.
  • 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.
  • 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.
  • 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.
  • the projection device 120 provided in this application embodiment will be described below with reference to specific embodiments.
  • Figure 4 is a schematic diagram of the projection device 120 provided in Embodiment 1 of this application.
  • 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, and the fifth lens 15 is also 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.
  • the number of lenses with optical power in lens group 101 is five, which meets the requirements.
  • the second lens 12 has negative optical power. As shown in Figure 4, the second lens 12 is located on the first side and is closest to the aperture stop 102, which also meets the requirements.
  • 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.
  • the lens closest to the object side in lens 10 is the fifth lens 15.
  • Table 1 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment.
  • 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
  • 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
  • S11 is the object-side surface of the fifth lens 15.
  • S12 is the image-side surface of the cover glass 103
  • S13 is the object-side surface of the cover glass 103.
  • OBJ is the projection surface
  • ImgH is the imaging surface.
  • Table 2 shows the aspheric coefficients of each order in this embodiment.
  • 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
  • A4, A6, A8, ..., A30 are aspherical coefficients.
  • Ai corresponds to the i-th order coefficients in Table 2; for example, A4 corresponds to the 4th order coefficients in Table 2.
  • aspherical surface shape z of a spherical mirror can also be calculated using other aspherical formulas, which will not be elaborated here.
  • Table 3 shows the optical parameters of the lens 10 provided in this embodiment.
  • 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.
  • 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
  • f3 is the focal length of the third lens
  • f4 is the focal length of the fourth lens 14
  • f5 is the focal length of the fifth lens 15.
  • Figure 5 shows the spherical chromatic aberration diagram of lens 10 in Figure 4.
  • the vertical axis represents the normalized pupil coordinates
  • the horizontal axis represents the aberration in the axial direction, in millimeters.
  • the three curves correspond to the axial aberration curves of light with a wavelength of 625 nm, 550 nm, and 455 nm after passing through lens 10 in this embodiment.
  • the axial aberration is controlled within a very small range, achieving good correction.
  • Figure 6 shows the astigmatism field curvature of lens 10 in Figure 4
  • Figure 7 shows the distortion of lens 10 in Figure 4.
  • S represents the field curvature value of light with a wavelength of 525 nm in the meridional image plane
  • T represents the field curvature value of light with a wavelength of 525 nm in the sagittal image plane.
  • the solid line represents the distortion value of light with a center wavelength of 525 nm passing through lens 10 of this embodiment.
  • the lens 10 provided in this embodiment controls the field curvature and distortion within the corresponding range, and has high imaging quality.
  • 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, and the fifth lens 15 is also 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.
  • the number of lenses with optical power in lens group 101 is five, which meets the requirements.
  • the second lens 12 has negative optical power. As shown in Figure 8, the second lens 12 is located on the first side and is closest to the aperture stop 102, which also meets the requirements.
  • 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.
  • the lens closest to the object side in lens 10 is the fifth lens 15.
  • 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.
  • Table 4 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment 2.
  • 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
  • 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
  • S11 is the object-side surface of the fifth lens 15.
  • S12 is the image-side surface of the cover glass 103
  • S13 is the object-side surface of the cover glass 103.
  • OBJ is the projection surface
  • ImgH is the imaging surface.
  • 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
  • Vd is the Abbe number of the optical element.
  • Table 5 shows the aspheric coefficients of each order in this embodiment 2.
  • 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:
  • 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
  • A4, A6, A8, ..., A30 are aspherical coefficients.
  • Ai corresponds to the i-th order coefficients in Table 2; for example, A4 corresponds to the 4th order coefficients in Table 2.
  • aspherical surface shape z of a spherical mirror can also be calculated using other aspherical formulas, which will not be elaborated here.
  • Table 6 shows the optical parameters of the lens 10 provided in this embodiment 2.
  • 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.
  • 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
  • f3 is the focal length of the third lens
  • f4 is the focal length of the fourth lens 14
  • f5 is the focal length of the fifth lens 15.
  • Figure 9 shows the spherical chromatic aberration diagram of lens 10 in Figure 8.
  • the vertical axis represents the normalized pupil coordinates
  • the horizontal axis represents the aberration in the axial direction, in millimeters.
  • the three curves correspond to the axial aberration curves of light with a wavelength of 625 nm, 550 nm, and 455 nm after passing through lens 10 in this embodiment.
  • the axial aberration is controlled within a very small range, achieving good correction.
  • Figure 10 shows the astigmatism field curvature of lens 10 in Figure 8
  • Figure 11 shows the distortion of lens 10 in Figure 8.
  • S represents the field curvature value of light with a wavelength of 525 nm in the meridional image plane
  • T represents the field curvature value of light with a wavelength of 525 nm in the sagittal image plane.
  • the solid line represents the distortion value of light with a center wavelength of 525 nm passing through lens 10 of this embodiment.
  • the lens 10 provided in this embodiment controls the field curvature and distortion within the corresponding range, and has high imaging quality.
  • Figure 12 is a schematic diagram of the projection device 120 provided in Embodiment 3 of this application.
  • 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, and the fifth lens 15 is also 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.
  • the number of lenses with optical power in lens group 101 is five, which meets the requirements.
  • the second lens 12 has negative optical power. As shown in Figure 12, the second lens 12 is located on the first side and is closest to the aperture stop 102, which also meets the requirements.
  • 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.
  • the lens closest to the object side in lens 10 is the fifth lens 15.
  • 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.
  • Table 7 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment 3.
  • 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
  • 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
  • S11 is the object-side surface of the fifth lens 15.
  • S12 is the image-side surface of the cover glass 103
  • S13 is the object-side surface of the cover glass 103.
  • OBJ is the projection surface
  • ImgH is the imaging surface.
  • 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
  • Vd is the Abbe number of the optical element.
  • Table 8 shows the aspheric coefficients of each order in this embodiment 3.
  • 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:
  • 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
  • A4, A6, A8, ... A30 are aspherical coefficients.
  • 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.
  • aspherical surface shape z of a spherical mirror can also be calculated using other aspherical formulas, which will not be elaborated here.
  • Table 9 shows the optical parameters of the lens 10 provided in this embodiment 3.
  • 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.
  • 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
  • f3 is the focal length of the third lens
  • f4 is the focal length of the fourth lens 14
  • f5 is the focal length of the fifth lens 15.
  • Figure 13 shows the spherical chromatic aberration diagram of lens 10 in Figure 12.
  • the vertical axis represents the normalized pupil coordinates
  • the horizontal axis represents the aberration in the axial direction, in millimeters.
  • the three curves correspond to the axial aberration curves of light with a wavelength of 625 nm, 550 nm, and 455 nm after passing through lens 10 in this embodiment.
  • the axial aberration is controlled within a very small range, achieving good correction.
  • Figure 14 shows the astigmatism field curvature of lens 10 in Figure 12, and Figure 15 shows the distortion of lens 10 in Figure 12.
  • S represents the field curvature value of light with a wavelength of 525 nm in the meridional image plane
  • T represents the field curvature value of light with a wavelength of 525 nm in the sagittal image plane.
  • the solid line represents the distortion value of light with a center wavelength of 525 nm passing through lens 10 of this embodiment.
  • the lens 10 provided in this embodiment controls the field curvature and distortion within a corresponding range, and has high imaging quality.
  • Figure 16 is a schematic diagram of the projection device 120 provided in Embodiment 4 of this application.
  • 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, and the fifth lens 15 is also 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.
  • the number of lenses with optical power in lens group 101 is five, which meets the requirements.
  • the second lens 12 has negative optical power. As shown in Figure 16, the second lens 12 is located on the first side and is closest to the aperture stop 102, which also meets the requirements.
  • 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.
  • the lens closest to the object side in lens 10 is the fifth lens 15.
  • 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.
  • Table 10 shows the optical parameters of each optical element in the projection device 120 provided in this embodiment 4.
  • all the lenses in lens 10 are spherical lenses.
  • 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
  • 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
  • ImgH is the imaging surface.
  • 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
  • Vd is the Abbe number of the optical element.
  • Table 11 shows the optical parameters of the lens 10 provided in this embodiment 4.
  • 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.
  • 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
  • f3 is the focal length of the third lens
  • f4 is the focal length of the fourth lens 14
  • f5 is the focal length of the fifth lens 15.
  • Figure 17 shows the spherical chromatic aberration diagram of lens 10 in Figure 16.
  • the vertical axis represents the normalized pupil coordinates
  • the horizontal axis represents the aberration in the axial direction, in millimeters.
  • the three curves correspond to the axial aberration curves of light with a wavelength of 625 nm, 550 nm, and 455 nm after passing through lens 10 in this embodiment.
  • the axial aberration is controlled within a very small range, achieving good correction.
  • Figure 18 shows the astigmatism field curvature of lens 10 in Figure 16, and Figure 19 shows the distortion of lens 10 in Figure 16.
  • S represents the field curvature value of light with a wavelength of 525 nm in the meridional image plane
  • T represents the field curvature value of light with a wavelength of 525 nm in the sagittal image plane.
  • the solid line represents the distortion value of light with a center wavelength of 525 nm passing through lens 10 of this embodiment.
  • the lens 10 provided in this embodiment controls the field curvature and distortion within a corresponding range, and has high imaging quality.

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Abstract

本申请实施例提供一种镜头、投影装置、车灯装置和交通工具，属于光学技术领域。其中，镜头包括透镜组和光阑。其中，透镜组包括从像侧到物侧排列的至少五个镜片，透镜组中具有光焦度的镜片的数量为至少五个，透镜组中具有负光焦度的镜片的数量为至少一个。光阑包括沿像侧到物侧的方向相对设置的第一侧和第二侧，第一侧和第二侧中的至少一侧设置有镜片，其中：在第一侧设置有镜片时，位于第一侧且最靠近光阑的镜片具有负光焦度。和/或，在第二侧设置有镜片时，位于第二侧且最靠近光阑的镜片具有负光焦度。如此设置，使得镜头能够与微型发光二极管显示芯片等直显芯片配合并构成体积小的投影装置，从而可以减小车灯装置的体积。

Description

镜头、投影装置、车灯装置和交通工具
本申请要求于2024年07月03日提交中国专利局、申请号为202410893097.7、申请名称为“镜头、投影装置、车灯装置和交通工具”的中国专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本申请实施例涉及光学技术领域，特别涉及一种镜头、投影装置、车灯装置和交通工具。
背景技术
随着智能汽车技术的发展，需要车载大灯具有传统的照明功能，还要有着可投影图案，以满足迎宾、信息交互、自动驾驶等方面愈来愈多的需求。相关技术中，车灯装置包括镜头、调制器件、光源和曲面镜，曲面镜用于将光源发出的光束反射至调制器件，调制器件为硅基液晶(liquid crystal on silicon，LCOS)，调制器件根据来自曲面镜的光束调制出成像光束并将成像光束出射至镜头。然而，为了满足调制器件、光源和曲面镜等器件的布置要求，镜头的后焦长度较长，导致车灯装置的体积大，从而提高了车灯装置在交通工具中的布置难度。
发明内容
本申请实施例提供一种镜头、投影装置、车灯装置和交通工具，该镜头的后焦长度小，能够与微型发光二极管显示芯片等直显芯片配合并构成体积小的投影装置，从而可以减小车灯装置的体积，进而降低了在交通工具中布置车灯装置的难度。
本申请第一方面提供一种镜头，该镜头包括透镜组和光阑。其中，透镜组包括从像侧到物侧排列的至少五个镜片，透镜组中具有光焦度的镜片的数量为至少五个，透镜组中具有负光焦度的镜片的数量为至少一个。光阑包括沿像侧到物侧的方向相对设置的第一侧和第二侧，第一侧靠近像侧，第二侧靠近物侧，第一侧和第二侧中的至少一侧设置有镜片，其中：在第一侧设置有镜片时，位于第一侧且最靠近光阑的镜片具有负光焦度。和/或，在第二侧设置有镜片时，位于第二侧且最靠近光阑的镜片具有负光焦度。
本申请实施例提供的镜头的后焦长度小，使得镜头可以与微型发光二极管显示芯片等直显芯片配合并构成体积小的投影装置，投影装置应用于车灯装置，可以减小车灯装置的体积，进而降低了在交通工具中布置车灯装置的难度。另外，镜头可以具备大光圈和大视场角的特性，能增加镜头的成像范围，使得镜头可以与大靶面的微型发光二极管显示芯片等直显芯片配合，例如与万级像素的直显芯片配合，也就是说，可以实现镜头的大靶面设计，有利于发光面积的增加，从而可以提高投影装置的发光功率，进而可以提高投影装置的明亮度。此外，还可以提高镜头的光学性能，从而提高成像质量，降低畸变。
在一种可能的实施方式中，镜头满足关系式：4.5mm＜BFL＜10mm，其中，BFL为镜头的后焦长度。
这样，通过将镜头的后焦长度控制在4.5mm～10mm之间，可以进一步地减小镜头与微型发光二极管显示芯片等直显芯片之间的距离，可以进一步地减小投影装置的体积。此外，还可以确保镜头具备大光圈和大视场角的特性。
在一种可能的实施方式中，镜头满足关系式：30.02mm＜R1＜100mm，其中，R1为透镜组中最靠近像侧的镜片的像侧面的曲率半径。
这样，通过让镜头通过满足关系式：30.02mm＜R1＜100mm，可以在同时实现大光圈和大视场角的前提下，降低镜头中最靠近像侧的镜片的制造难度，提高良率，以提升经济性。另外，还可以方便像差的校正，提升镜头的光学性能。除此之外，还可以避免镜头中最靠近像侧的镜片的像侧面太突出或太平，有效平衡镜头的光学性能和车灯造型。
在一种可能的实施方式中，镜头满足关系式：15mm＜R2＜30mm，其中，R2为透镜组中最靠近物侧的镜片的物侧面的曲率半径。
这样，通过让镜头通过满足关系式：15mm＜R2＜30mm，可以在同时实现大光圈和大视场角的前提下，降低镜头中最靠近物侧的镜片的制造难度，提高良率，以提升经济性。另外，也可以避免镜头中最靠近物侧的镜片的物侧面太突出或太凹，有效平衡镜头的光学性能和车灯造型。
在一种可能的实施方式中，第一侧和第二侧均设置有镜片。
这样，将光阑设置于透镜组中最靠近像侧的镜片与透镜组中最靠近物侧的镜片之间，可以进一步地减小镜头的体积，并提升镜头的经济性。
在一种可能的实施方式中，透镜组中的至少一个镜片为具有光焦度的非球面镜。
这样，在透镜组中设置能够修正像差的非球面镜，可以进一步地提高镜头的光学性能，提高成像质量。
在一种可能的实施方式中，透镜组中具有光焦度的所有镜片均为球面镜。
这样，在让镜头具备大光圈和大视场角的特性的同时，可以降低各个镜片的制造难度，从而降低镜头的成本，进而提升镜头的经济性。
在一种可能的实施方式中，透镜组中具有负光焦度的镜片的数量为一个。
这样，使镜头具备大光圈和大视场角的同时，可以减小具有负光焦度的镜片对镜头的光焦度的影响，进一步地提高镜头的综合性能。
本申请第二方面提供一种投影装置，该投影装置包括显示单元和如第一方面任一项的镜头。其中，显示单元的显示面与镜头中最靠近物侧的镜片相对，显示单元被配置成形成显示图像，并将显示图像经过显示面传输至镜头。
由于镜头的后焦长度小并具备大靶面设计，使得镜头可以与至少是万级像素的显示单元配合，不仅可以减小投影装置的体积，而且还可以提高投影装置的明亮度。另外，还可以简化投影装置的结构，提高投影装置的性能。
在一种可能的实施方式中，显示单元为微型发光二极管显示芯片、次毫米发光二极管显示芯片或薄膜场效应晶体管显示芯片。
这样，显示单元采用微型发光二极管、次毫米发光二极管等阵列光源与芯片集成的显示芯片，简化了投影装置的结构，还可以减小投影装置的体积。
本申请第三方面提供一种车灯装置，该车灯装置包括外壳和如第二方面任一项的投影装置，投影装置的至少部分设置于外壳的内部。
本申请第四方面提供一种交通工具，该交通工具包括如第三方面的车灯装置。
附图说明
图1为相关技术中提供的一种车灯装置的结构示意图；
图2为本申请实施例提供的一种车灯装置的结构示意图；
图3为本申请实施例提供的一种镜头的结构示意图；
图4为本申请实施例一提供的投影装置的结构示意图；
图5为图4中的镜头的球色差图；
图6为图4中的镜头的像散场曲图；
图7为图4中的镜头的畸变图；
图8为本申请实施例二提供的投影装置的结构示意图；
图9为图8中的镜头的球色差图；
图10为图8中的镜头的像散场曲图；
图11为图8中的镜头的畸变图；
图12为本申请实施例三提供的投影装置的结构示意图；
图13为图12中的镜头的球色差图；
图14为图12中的镜头的像散场曲图；
图15为图12中的镜头的畸变图；
图16为本申请实施例四提供的投影装置的结构示意图；
图17为图16中的镜头的球色差图；
图18为图16中的镜头的像散场曲图；
图19为图16中的镜头的畸变图。
附图标记说明：
100、车灯装置；
110、外壳；
120、投影装置；
130、预设位置；
10、镜头；101、透镜组；102、光阑；103、盖板玻璃；
20、显示单元；
11、第一镜片；12、第二镜片；13、第三镜片；14、第四镜片；15、第五镜片。
具体实施方式
本申请的实施方式部分使用的术语仅用于对本申请的具体实施例进行解释，而非旨在限定本申请。
为便于理解，首先对本申请实施例所涉及的相关技术术语进行解释和说明。
焦距，也称为焦长，是光学系统中衡量光的聚集或发射散的度量方式，指无限远的景物通过透镜或透镜组在焦平面结成清晰影像时，透镜或透镜组的光学中心至焦平面的垂直距离。
像侧，以镜头为界，图像所在的一侧为像侧，镜片面向像侧的一面为镜片的像侧面。
物侧，显示单元所在的一侧为物侧，镜片面向物侧的一面为物侧面。
总长度(total track length，简称TTL)，指镜头中邻近物侧设置的第一镜片的顶点至镜头成像面的总长度，也被称为光学总长。
后焦长度(back focal length，简称BFL)，定义为镜头中最靠近成像面的镜片至显示单元的距离。
光焦度，表征镜片对入射平行光束的屈折能力。
正光焦度，表示镜片有正的焦距，有汇聚光线的效果。
负光焦度，表示镜片有负的焦距，有发散光线的效果。
光圈，是用来控制光线透过镜头进入电子设备内部的光量的装置，通常在镜头内，表达光圈大小用F#(F-number)数值表示。
光圈数F#，是镜头的焦距/镜头通光直径得出的相对值(相对孔径的倒数)，光圈数F#值越小，在同一单位时间内的进光量越多。
盖板玻璃(cover glass，CG)，用于保护显示芯片。
靶面，指图像传感器的成像部分，在本申请实施例中，指的是显示图像的出光面(如显示单元的显示面)，靶面越大，显示图像可用的发光面积越大，显示图像的亮度越高。
视场角(field of view，简称FOV)，以镜头为顶点，以图像可通过镜头的最大范围的两条边缘构成的夹角，称为视场角。视场角的大小决定了镜头的视野范围，视场角越大，视野就越大。
轴向色差，也称为纵向色差或位置色差，一束平行于光轴的光线，在经过镜头后会聚于前后不同的位置，这种像差称为位置色差或轴向色差。这是由于镜头对各个波长的光所成像的位置不同，使得最后成像时不同色的光的像其成像面不能完全重合，复色光散开形成色散。
畸变(distortion)，也称为失真，光学系统对物体所成的像相对于物体本身而言的失真程度。畸变是由于光阑像差的影响，不同视场的主光线通过光学系统后与高斯像面的交点高度不等于理想像高，两者之差就是畸变。因此畸变只改变轴外物点在理想面上的成像位置，使像的形状产生失真，但不影响像的清晰度。
图1为相关技术中提供的一种车灯装置的结构示意图。
在相关技术中，参见图1所示，车灯装置包括镜头210、调制器件220、光源230和曲面镜240，曲面镜240用于将光源230发出的光束反射至调制器件220，调制器件220为硅基液晶(liquid crystal on silicon，LCOS)，调制器件220根据来自曲面镜240的光束调制出成像光束并将成像光束出射至镜头210。
然而，为了满足调制器件220、光源230和曲面镜240等器件的布置要求，镜头210的后焦长度较长，导致车灯装置的体积大，从而提高了车灯装置在交通工具中的布置难度。另外，构成车灯装置的零件数量多，导致了车灯装置的结构复杂。此外，车灯装置中的光路复杂，导致照明效率低。
有鉴于此，本申请实施例提供一种镜头、投影装置、车灯装置和交通工具，该镜头的后焦长度小，使得镜头可以与微型发光二极管显示芯片等直显芯片配合并构成体积小的投影装置，投影装置应用于车灯装置，可以减小车灯装置的体积，进而降低了在交通工具中布置车灯装置的难度。另外，镜头可以具备大光圈和大视场角的特性，能增加镜头的成像范围，使得镜头可以与大靶面的微型发光二极管显示芯片等直显芯片配合，例如与万级像素的直显芯片配合，也就是说，可以实现镜头的大靶面设计，有利于发光面积的增加，从而可以提高投影装置的发光功率，进而可以提高投影装置的明亮度。此外，还可以提高镜头的光学性能，从而提高成像质量，降低畸变。
本申请实施例提供的交通工具可以包括但不局限于为汽车、卡车、摩托车、船、飞机、直升飞机、割草机、娱乐车、游乐场车辆、施工设备、电车、高尔夫球车、火车或手推车等。另外，本申请实施例提供的交通工具还可以是未来新出现的交通工具。
其中，汽车可以是电动汽车、燃油车或混合动力车，例如纯电动汽车、增程式电动汽车、新能源汽车、燃料电池汽车、混合动力电动汽车等。示例性地，下文以汽车为上述交通工具为例来进行说明。
示例性地，交通工具可以包括车灯装置100和交通工具主体。其中，交通工具主体可以包括座椅、仪表台、车身等让交通工具的结构或功能完整的零部件，例如制动系统、驱动系统、传感器等。车灯装置100具备照明功能和投影功能，能够进行照明或满足投影需求。
其中，车灯装置100可以包括但不局限于为像素显示车灯、近场迎宾车灯、行人或交互车灯、汽车大灯等。示例性地，在本申请实施例中，以汽车大灯为上述车灯装置100为例进行说明，汽车大灯可以安装在汽车的前方或后方，因此，汽车大灯在实现照明需求的同时，还可以实现显示需求。
图2为本申请实施例提供的一种车灯装置100的结构示意图。
参见图2所示，车灯装置100可以包括外壳110和投影装置120。其中，投影装置120的至少部分设置于外壳110的内部，例如图2所示，投影装置120设置于外壳110的内部，当然，投影装置120也可以一部分设置于外壳110的内部、另一部分设置于外壳110的外部。投影装置120，用于实现车灯装置100的照明及其他显示需求。
需要说明的是，本申请实施例提供的投影装置120除了应用于车灯装置100外，还可以应用于投影仪、抬头显示(head up display，简称HUD)设备、增强显示(augmented reality，AR)眼镜等设备，实现显示需求。
示例性地，继续参见图2所示，投影装置120可以包括显示单元20和镜头10。其中，显示单元20的显示面与镜头10中最靠近物侧的镜片相对，也就是说，显示单元20设置于镜头10的物侧并沿镜头10的光轴方向与显示单元20的显示面相对。显示单元20被配置成形成显示图像，并将显示图像经过显示面传输至镜头10。镜头10可以对显示图像起到放大、调焦、对焦等作用，显示图像经过镜头10后照射至预设位置130，实现对显示图像的投影显示。
预设位置130可以理解为用于承载投影装置120投影的显示图像，实现对显示图像的显示。预设位置130可以为投影幕布、车窗、玻璃、墙面、地面等任何能够承载显示图像的结构，例如投影装置120可以将显示图像投影至交通工具前方的地面上，使得乘客观看地面的同时看到显示图像。
显示单元20可以为微型发光二极管(light-emitting diode，简称Micro LED)显示芯片、次毫米发光二极管(Mini LED)显示芯片或薄膜场效应晶体管(thin film transistor，TFT)显示芯片等直显芯片。通过采用微型发光二极管、次毫米发光二极管等阵列光源与芯片集成的显示芯片，简化了显示单元20的结构，从而简化了投影装置120的结构，还可以减小投影装置120的体积。
由于本申请实施例提供的镜头10的后焦长度小并具备大靶面设计，使得镜头10能够支持大靶面的直显芯片，例如可以与至少是万级像素的直显芯片配合，不仅可以减小投影装置120的体积，而且还可以提高投影装置120的明亮度。
下面结合附图，对本申请实施例提供的镜头10进行说明。
图3为本申请实施例提供的一种镜头10的结构示意图。
参见图3所示，镜头10可以包括透镜组101和光阑102。其中，透镜组101包括从像侧到物侧排列的至少五个镜片，例如图3所示，透镜组101包括五个镜片，五个镜片为从像侧至物侧排列的第一镜片11、第二镜片12、第三镜片13、第四镜片14和第五镜片15，当然，透镜组101的镜片数量也可以超过五个。透镜组101中具有光焦度的镜片的数量为至少五个，例如图3所示，透镜组101中具有光焦度的镜片数量为五个，当然，透镜组101中具有光焦度的镜片的数量也可以超过五个。透镜组101中具有负光焦度的镜片的数量为至少一个，例如图3所示，透镜组101中具有负光焦度的镜片的数量为一个，当然，透镜组101中具有负光焦度的镜片的数量也可以超过一个。
继续参见图3所示，光阑102包括沿像侧到物侧的方向相对设置的第一侧和第二侧，第一侧靠近像侧，第二侧靠近物侧，第一侧和第二侧中的至少一侧设置有镜片。其中，在第一侧设置有镜片时，位于第一侧且最靠近光阑102的镜片具有负光焦度。和/或，在第二侧设置有镜片时，位于第二侧且最靠近光阑102的镜片具有负光焦度。也就是说，当具有负光焦度的镜片为一个时，具有负光焦度的镜片可以位于第一侧或第二侧，并最靠近光阑102设置，即光阑102与具有负光焦度的镜片相邻；或者，当具有负光焦度的镜片的数量为两个以上时，其中两个具有负光焦度的镜片分别位于第一侧和第二侧，并分别最靠近光阑102设置，即光阑102位于该其中两个具有负光焦度的镜片之间。
具有负光焦度的镜片对镜头10的光焦度起到的负的贡献，将具有负光焦度的镜片设置在光阑102的旁边，使得具有负光焦度的镜片对镜头10的光焦度的影响变小，有利于发挥镜片的综合性能，从而可以提高镜头10的综合性能。
通过控制透镜组101中各个镜片的光焦度布置以及光阑102和具有负光焦度的镜片的位置，可以减小镜头10的后焦长度，将镜头10的后焦长度控制在合理范围内，使得镜头10可以与微型发光二极管显示芯片等直显芯片配合并构成体积小的投影装置120，投影装置120应用于车灯装置100，可以减小车灯装置100的体积，进而降低了在交通工具中布置车灯装置100的难度。
另外，还可以使镜头10具备大光圈和大视场角的特性，能增加镜头10的成像范围，使得镜头10可以与大靶面的微型发光二极管显示芯片等直显芯片配合，例如与万级像素的直显芯片配合，也就是说，可以实现镜头10的大靶面设计，有利于发光面积的增加，从而可以提高投影装置120的发光功率，进而可以提高投影装置120的明亮度。此外，还可以提高镜头10的光学性能，从而提高成像质量，降低畸变。
需要说明的是，镜头10除了通过具有光焦度的至少五个镜片(例如图3中镜头10通过五个具有光焦度的镜片构成)构成外，镜头10也可以通过一部分具有光焦度的镜片和一部分不具有光焦度的镜片构成，例如，镜头10可以包括五个具有光焦度的镜片和两个不具有光焦度的镜片构成。
示例性地，参见图3所示，第一侧和第二侧均可以设置有镜片，也就是说，将光阑102设置于透镜组101中最靠近像侧的镜片与透镜组101中最靠近物侧的镜片之间，可以进一步地减小镜头10的体积，并提升镜头10的经济性。
参见图3所示，第一侧设置有第一镜片11和第二镜片12，第二侧设置有第三镜片13、第四镜片14和第五镜片15。由此可知，设置于第一侧的镜片数量与设置于第二侧的镜片数量不同。但是，在一些实施例中，设置于第一侧的镜片数量与设置于第二侧的镜片数量也可以相同。
示例性地，透镜组101中具有负光焦度的镜片的数量可以为一个，例如图3所示，具有负光焦度的镜片的数量为一个，此时，具有负光焦度的镜片可以位于第一侧或第二侧并最靠近光阑102设置。
鉴于具有负光焦度的镜片对镜头10的光焦度起到的负的贡献，将具有负光焦度的镜片的数量设置为一个，可以进一步地减小具有负光焦度的镜片对镜头10的光焦度的影响，有助于进一步地提高镜头10的综合性能。
在一些可能地实现方式中，镜头10还可以满足关系式：4.5mm＜BFL＜10mm，其中，BFL为镜头10的后焦长度。
这样，通过将镜头10的后焦长度控制在4.5mm～10mm之间，可以进一步地减小镜头10与微型发光二极管显示芯片等直显芯片之间的距离，可以进一步地减小投影装置120的体积。此外，还可以确保镜头10具备大光圈和大视场角的特性，使得镜头10能够与大靶面的直显芯片配合，提升投影装置120的明亮度。此外，还可以保证镜头10的成像质量。
对于镜头10的后焦长度BFL的具体取值，这里不作限制。其中，镜头10的后焦长度BFL可以为4.55mm、4.8mm、5mm、5.35mm、5.55mm、6mm、6.55mm、7mm、7.698mm、8mm、8.556mm、9mm、9.355mm、9.55mm等。
在一些可能地实现方式中，镜头10还可以满足关系式：30.02mm＜R1＜100mm，其中，R1为透镜组101中最靠近像侧的镜片的像侧面的曲率半径。
这样，通过让镜头10通过满足关系式：30.02mm＜R1＜100mm，可以在同时实现大光圈和大视场角的前提下，降低镜头10中最靠近像侧的镜片的制造难度，提高良率，以提升经济性。另外，还可以方便像差的校正，提升镜头10的光学性能。除此之外，还可以避免镜头10中最靠近像侧的镜片的像侧面太突出或太平，有效平衡镜头10的光学性能和车灯造型。
对于R1的具体取值，这里不作限制。其中，R1可以为30.5mm、31mm、35mm、40mm、45.55mm、50.6mm、56.55mm、60mm、67.698mm、70mm、75.654mm、80mm、855mm、90mm等。
在一些可能地实现方式中，镜头10满足关系式：15mm＜R2＜30mm，其中，R2为透镜组101中最靠近物侧的镜片的物侧面的曲率半径。
这样，通过让镜头10通过满足关系式：15mm＜R2＜30mm，可以在同时实现大光圈和大视场角的前提下，降低镜头10中最靠近物侧的镜片的制造难度，提高良率，以提升经济性。另外，也可以避免镜头10中最靠近物侧的镜片的物侧面太突出或太凹，有效平衡镜头10的光学性能和车灯造型。
对于R2的具体取值，这里不作限制。其中，R2可以为15.315mm、16mm、16.5mm、17mm、17.55mm、18mm、19mm、20mm、21mm、23.65mm、25mm、25.98mm、28mm、29.5mm等。
在一些可能地实现方式中，透镜组101中的至少一个镜片可以为具有光焦度的非球面镜，例如图3所示，透镜组101中的非球面镜的数量可以为一个，当然，非球面镜的数量也可以超过一个。
这样，在透镜组101中设置能够修正像差的非球面镜，可以进一步地提高镜头10的光学性能，提高成像质量。另外，非球面镜的数量越多，那么对镜头10的光学性能的也越大。
需要说明的是，非球面镜的像侧面和物侧面中的至少一个可以为非球面，非球面镜的非球面的数量越多，那么对镜头10的光学性能的提升越大。
对于非球面镜的具体位置，这里不作限制。在一些实施例中，非球面镜的数量可以为两个，两个非球面镜可以位于第二侧并最靠近光阑102设置，也就是说，两个非球面镜位于光阑102和显示单元20之间，两个非球面镜为位于第二侧的镜片中最靠近光阑102的两个镜片。在另一些实施例中，非球面镜的数量也可以为一个，非球面镜也可以为透镜组101中最靠近像侧的镜片。
在一些可能地实现方式中，透镜组101中具有光焦度的所有镜片也可以均为球面镜。
这样，在让镜头10具备大光圈和大视场角的特性的同时，可以降低各个镜片的制造难度，从而降低镜头10的成本，进而提升镜头10的经济性。此外，也可以减小镜头10的后焦长度，确保镜头10可以与直显芯片配合，并实现大靶面设计。
在一些可能的实现方式中，透镜组101中的所有镜片的材质均可以相同，例如，透镜组101中的所有镜片的材质均可以为光学玻璃或塑料。
在一些可能得实现方式中，透镜组101也可以通过至少两种不同材质的镜片构成，例如，透镜组101中的一部分镜片的材质可以为光学玻璃、另一部分可以为塑料。
在一些可能的实现方式中，参见图3所示，镜头10还可以包括盖板玻璃103。其中，盖板玻璃103用于设置于透镜组101与显示单元20之间，盖板玻璃103用于保护显示单元20。
在一些可能的实现方式中，镜头10还可以包括用于校正色彩偏差的滤光片(图中未示出)。其中，滤光片用于设置于透镜组101和显示单元20之间。
需要说明的是，镜头10可以包括盖板玻璃103和滤光片中一个，或者，镜头10也可以包括盖板玻璃103和滤光片。
下面结合具体实施例对本申请实施例提供的投影装置120进行说明。
实施例一：
图4为本申请实施例一提供的投影装置120的结构示意图。
参见图4所示，投影装置120可以包括镜头10和显示单元20。其中，镜头10包括透镜组101、光阑102和盖板玻璃103。透镜组101包括从像侧到物侧依次排列的第一镜片11、第二镜片12、第三镜片13、第四镜片14、第五镜片15。第一镜片11最靠近像侧，第五镜片15最靠近像侧，光阑102设置于第二镜片12和第三镜片13之间，盖板玻璃103设置于第五镜片15和显示单元20之间。第一镜片11到第五镜片15的五个镜片的材质均可以为光学玻璃或塑料。显示单元20可以为Micro LED显示芯片、Mini LED显示芯片或TFT显示芯片等直显芯片。
第一镜片11具有正光焦度，第一镜片11的焦距f1＝77.326mm。
第二镜片12具有负光焦度，第二镜片12的焦距f2＝-37.669mm。
第三镜片13具有正光焦度，第三镜片13的焦距f3＝71.737mm。
第四镜片14具有正光焦度，第四镜片14的焦距f4＝34.732mm。
第五镜片15具有正光焦度，第五镜片15的焦距f5＝1520.703mm。
由此可知，透镜组101中具有光焦度的镜片的数量为五个，满足要求。另外，第二镜片12具备负光焦度，参见图4所示，第二镜片12位于第一侧并最靠近光阑102，满足要求。
镜头10中最靠近像侧的镜片为第一镜片11，第一镜片11的像侧面的曲率半径R1＝82.5151mm，大于30.02mm且小于100mm，满足要求。
镜头10中最靠近物侧的镜片为第五镜片15，第五镜片15的物侧面的曲率半径R2＝15.87mm，大于15mm且小于30mm，满足要求。
镜头10的后焦长度BFL＝7.25mm，大于4.5mm且小于10mm，满足要求。
表1示出了本实施例一提供的投影装置120中的各光学元件的光学参数。
其中，S1为第一镜片11的像侧面，S2为第一镜片11的物侧面。S3为第二镜片12的像侧面，S4为第二镜片12的物侧面。S5为光阑102。S6为第三镜片13的像侧面，S7为第三镜片13的物侧面。S8为第四镜片14的像侧面，S9为第四镜片14的物侧面。S10为第五镜片15的像侧面，S11为第五镜片15的物侧面。S12为盖板玻璃103的像侧面，S13为盖板玻璃103的物侧面。OBJ为投影面，ImgH为成像面。
R为光学元件(如镜片或玻璃盖板等)在光轴对应位置处的曲率半径，Th为光学元件在光轴方向上的面厚度，Nd为d线照射至各光学元件的折射率，Vd为光学元件的阿贝数。
表2示出了本实施例一的各阶非球面系数。
由表2可知，镜头10中的第三镜片13和第四镜片14均为非球面镜，也即该镜头10中包括有4个非球面，各个非球面镜的非球面面型z可以通过以下非球面公式计算：
其中，z为非球面的矢高，r为非球面的径向坐标，c为非球面顶点球曲率，k为二次曲面常数，A4、A6、A8、…A30为非球面系数。另外，Ai对应的是表2中的i阶系数，例如，A4对应的是表2中的4阶系数。
需要说明的是，球面镜的非球面面型z也可以通过其他非球面公式进行计算，这里不再一一赘述。
表3示出了本实施例一提供的镜头10的光学参数。

由表3可知，本申请实施例一所提供的镜头10兼具大光圈、大视场角的特性，且具有较小的后焦长度。
其中，Fno为镜头10的光圈，BFL为镜头10的后焦长度，TTL为镜头10的光学总长，R1为镜头10中最靠近像侧的镜片的像侧面的曲率半径，R2为镜头10中最靠近物侧的镜片的物侧面的曲率半径，f1为第一镜片11的焦距，f2为第二镜片12的焦距，f3为第三镜片13的焦距，f4为第四镜片14的焦距，f5为第五镜片15的焦距。
图5为图4中的镜头10的球色差图。在图5中，纵坐标表示的是归一化光瞳坐标，横坐标表示轴向方向上的像差，单位为毫米。在图5中，三条曲线分别对应波长为625nm的光、波长为550nm的光和波长为455nm的光经过本实施例的镜头10后的轴向像差曲线。从图5可以看出，在本实施例中，轴向像差控制在一个很小的范围内，得到较好的校正。
图6为图4中的镜头10的像散场曲图，图7为图4中的镜头10的畸变图。在图6中，S表示波长为525nm的光在子午像面的场曲值，T表示波长为525nm的光在弧矢像面的场曲值。在图7中，实线表示中心波长为525nm的光经过本实施例的镜头10的畸变值。在本实施例中，结合图6和图7可知，本实施例提供的镜头10将场曲和畸变控制在相应范围内，具有高的成像质量。
实施例二：
图8为本申请实施例二提供的投影装置120的结构示意图。
参见图8所示，投影装置120可以包括镜头10和显示单元20。其中，镜头10包括透镜组101、光阑102和盖板玻璃103。透镜组101包括从像侧到物侧依次排列的第一镜片11、第二镜片12、第三镜片13、第四镜片14、第五镜片15。第一镜片11最靠近像侧，第五镜片15最靠近像侧，光阑102设置于第二镜片12和第三镜片13之间，盖板玻璃103设置于第五镜片15和显示单元20之间。第一镜片11到第五镜片15的五个镜片的材质均可以为光学玻璃或塑料。显示单元20可以为Micro LED显示芯片、Mini LED显示芯片或TFT显示芯片等直显芯片。
第一镜片11具有正光焦度，第一镜片11的焦距f1＝46.801mm。
第二镜片12具有负光焦度，第二镜片12的焦距f2＝-40.389mm。
第三镜片13具有正光焦度，第三镜片13的焦距f3＝41.173mm。
第四镜片14具有正光焦度，第四镜片14的焦距f4＝45.964mm。
第五镜片15具有正光焦度，第五镜片15的焦距f5＝357.239mm。
由此可知，透镜组101中具有光焦度的镜片的数量为五个，满足要求。另外，第二镜片12具备负光焦度，参见图8所示，第二镜片12位于第一侧并最靠近光阑102，满足要求。
镜头10中最靠近像侧的镜片为第一镜片11，第一镜片11的像侧面的曲率半径R1＝40.865mm，大于30.02mm且小于100mm，满足要求。
镜头10中最靠近物侧的镜片为第五镜片15，第五镜片15的物侧面的曲率半径R2＝15.391mm，大于15mm且小于30mm，满足要求。
镜头10的后焦长度BFL＝5.620mm，大于4.5mm且小于10mm，满足要求。
表4示出了本实施例二提供的投影装置120中的各光学元件的光学参数。

其中，S1为第一镜片11的像侧面，S2为第一镜片11的物侧面。S3为第二镜片12的像侧面，S4为第二镜片12的物侧面。S5为光阑102。S6为第三镜片13的像侧面，S7为第三镜片13的物侧面。S8为第四镜片14的像侧面，S9为第四镜片14的物侧面。S10为第五镜片15的像侧面，S11为第五镜片15的物侧面。S12为盖板玻璃103的像侧面，S13为盖板玻璃103的物侧面。OBJ为投影面，ImgH为成像面。
R为光学元件(如镜片或玻璃盖板等)在光轴对应位置处的曲率半径，Th为光学元件在光轴方向上的面厚度，Nd为d线照射至各光学元件的折射率，Vd为光学元件的阿贝数。
表5示出了本实施例二的各阶非球面系数。
由表5可知，镜头10中的第一镜片11为非球面镜，也即该镜头10中包括有2个非球面，第一镜片11的非球面面型z可以通过以下非球面公式计算：
其中，z为非球面的矢高，r为非球面的径向坐标，c为非球面顶点球曲率，k为二次曲面常数，A4、A6、A8、…A30为非球面系数。另外，Ai对应的是表2中的i阶系数，例如，A4对应的是表2中的4阶系数。
需要说明的是，球面镜的非球面面型z也可以通过其他非球面公式进行计算，这里不再一一赘述。
表6示出了本实施例二提供的镜头10的光学参数。
由表6可知，本申请实施例二所提供的镜头10兼具大光圈、大视场角的特性，且具有较小的后焦长度。
其中，Fno为镜头10的光圈，BFL为镜头10的后焦长度，TTL为镜头10的光学总长，R1为镜头10中最靠近像侧的镜片的像侧面的曲率半径，R2为镜头10中最靠近物侧的镜片的物侧面的曲率半径，f1为第一镜片11的焦距，f2为第二镜片12的焦距，f3为第三镜片13的焦距，f4为第四镜片14的焦距，f5为第五镜片15的焦距。
图9为图8中的镜头10的球色差图。在图9中，纵坐标表示的是归一化光瞳坐标，横坐标表示轴向方向上的像差，单位为毫米。在图9中，三条曲线分别对应波长为625nm的光、波长为550nm的光和波长为455nm的光经过本实施例的镜头10后的轴向像差曲线。从图9可以看出，在本实施例中，轴向像差控制在一个很小的范围内，得到较好的校正。
图10为图8中的镜头10的像散场曲图，图11为图8中的镜头10的畸变图。在图10中，S表示波长为525nm的光在子午像面的场曲值，T表示波长为525nm的光在弧矢像面的场曲值。在图11中，实线表示中心波长为525nm的光经过本实施例的镜头10的畸变值。在本实施例中，结合图10和图11可知，本实施例提供的镜头10将场曲和畸变控制在相应范围内，具有高的成像质量。
实施例三：
图12为本申请实施例三提供的投影装置120的结构示意图。
参见图12所示，投影装置120可以包括镜头10和显示单元20。其中，镜头10包括透镜组101、光阑102和盖板玻璃103。透镜组101包括从像侧到物侧依次排列的第一镜片11、第二镜片12、第三镜片13、第四镜片14、第五镜片15。第一镜片11最靠近像侧，第五镜片15最靠近像侧，光阑102设置于第二镜片12和第三镜片13之间，盖板玻璃103设置于第五镜片15和显示单元20之间。第一镜片11到第五镜片15的五个镜片的材质均可以为光学玻璃或塑料。显示单元20可以为Micro LED显示芯片、Mini LED显示芯片或TFT显示芯片等直显芯片。
第一镜片11具有正光焦度，第一镜片11的焦距f1＝53.949mm。
第二镜片12具有负光焦度，第二镜片12的焦距f2＝-30.622mm。
第三镜片13具有正光焦度，第三镜片13的焦距f3＝46.543mm。
第四镜片14具有正光焦度，第四镜片14的焦距f4＝46.857mm。
第五镜片15具有正光焦度，第五镜片15的焦距f5＝181.938mm。
由此可知，透镜组101中具有光焦度的镜片的数量为五个，满足要求。另外，第二镜片12具备负光焦度，参见图12所示，第二镜片12位于第一侧并最靠近光阑102，满足要求。
镜头10中最靠近像侧的镜片为第一镜片11，第一镜片11的像侧面的曲率半径R1＝45.505mm，大于30.02mm且小于100mm，满足要求。
镜头10中最靠近物侧的镜片为第五镜片15，第五镜片15的物侧面的曲率半径R2＝21.501mm，大于15mm且小于30mm，满足要求。
镜头10的后焦长度BFL＝8.869mm，大于4.5mm且小于10mm，满足要求。
表7示出了本实施例三提供的投影装置120中的各光学元件的光学参数。
其中，S1为第一镜片11的像侧面，S2为第一镜片11的物侧面。S3为第二镜片12的像侧面，S4为第二镜片12的物侧面。S5为光阑102。S6为第三镜片13的像侧面，S7为第三镜片13的物侧面。S8为第四镜片14的像侧面，S9为第四镜片14的物侧面。S10为第五镜片15的像侧面，S11为第五镜片15的物侧面。S12为盖板玻璃103的像侧面，S13为盖板玻璃103的物侧面。OBJ为投影面，ImgH为成像面。
R为光学元件(如镜片或玻璃盖板等)在光轴对应位置处的曲率半径，Th为光学元件在光轴方向上的面厚度，Nd为d线照射至各光学元件的折射率，Vd为光学元件的阿贝数。
表8示出了本实施例三的各阶非球面系数。
由表8可知，镜头10中的第一镜片11为非球面镜，也即该镜头10中包括有2个非球面，第一镜片11的非球面面型z可以通过以下非球面公式计算：
其中，z为非球面的矢高，r为非球面的径向坐标，c为非球面顶点球曲率，k为二次曲面常数，A4、A6、A8、…A30为非球面系数。另外，Ai对应的是表2中的i阶系数，例如，A4对应的是表2中的4阶系数。Conic系数指的是k，也就是二次曲面常数。
需要说明的是，球面镜的非球面面型z也可以通过其他非球面公式进行计算，这里不再一一赘述。
表9示出了本实施例三提供的镜头10的光学参数。
由表9可知，本申请实施例三所提供的镜头10兼具大光圈、大视场角的特性，且具有较小的后焦长度。
其中，Fno为镜头10的光圈，BFL为镜头10的后焦长度，TTL为镜头10的光学总长，R1为镜头10中最靠近像侧的镜片的像侧面的曲率半径，R2为镜头10中最靠近物侧的镜片的物侧面的曲率半径，f1为第一镜片11的焦距，f2为第二镜片12的焦距，f3为第三镜片13的焦距，f4为第四镜片14的焦距，f5为第五镜片15的焦距。
图13为图12中的镜头10的球色差图。在图13中，纵坐标表示的是归一化光瞳坐标，横坐标表示轴向方向上的像差，单位为毫米。在图13中，三条曲线分别对应波长为625nm的光、波长为550nm的光和波长为455nm的光经过本实施例的镜头10后的轴向像差曲线。从图13可以看出，在本实施例中，轴向像差控制在一个很小的范围内，得到较好的校正。
图14为图12中的镜头10的像散场曲图，图15为图12中的镜头10的畸变图。在图14中，S表示波长为525nm的光在子午像面的场曲值，T表示波长为525nm的光在弧矢像面的场曲值。在图15中，实线表示中心波长为525nm的光经过本实施例的镜头10的畸变值。在本实施例中，结合图14和图15可知，本实施例提供的镜头10将场曲和畸变控制在相应范围内，具有高的成像质量。
实施例四：
图16为本申请实施例四提供的投影装置120的结构示意图。
参见图16所示，投影装置120可以包括镜头10和显示单元20。其中，镜头10包括透镜组101、光阑102和盖板玻璃103。透镜组101包括从像侧到物侧依次排列的第一镜片11、第二镜片12、第三镜片13、第四镜片14、第五镜片15。第一镜片11最靠近像侧，第五镜片15最靠近像侧，光阑102设置于第二镜片12和第三镜片13之间，盖板玻璃103设置于第五镜片15和显示单元20之间。第一镜片11到第五镜片15的五个镜片的材质均可以为光学玻璃或塑料。显示单元20可以为Micro LED显示芯片、Mini LED显示芯片或TFT显示芯片等直显芯片。
第一镜片11具有正光焦度，第一镜片11的焦距f1＝46.620mm。
第二镜片12具有负光焦度，第二镜片12的焦距f2＝-39.654mm。
第三镜片13具有正光焦度，第三镜片13的焦距f3＝62.501mm。
第四镜片14具有正光焦度，第四镜片14的焦距f4＝64.770mm。
第五镜片15具有正光焦度，第五镜片15的焦距f5＝58.035mm。
由此可知，透镜组101中具有光焦度的镜片的数量为五个，满足要求。另外，第二镜片12具备负光焦度，参见图16所示，第二镜片12位于第一侧并最靠近光阑102，满足要求。
镜头10中最靠近像侧的镜片为第一镜片11，第一镜片11的像侧面的曲率半径R1＝49.097mm，大于30.02mm且小于100mm，满足要求。
镜头10中最靠近物侧的镜片为第五镜片15，第五镜片15的物侧面的曲率半径R2＝39.260mm，大于15mm且小于30mm，满足要求。
镜头10的后焦长度BFL＝5.190mm，大于4.5mm且小于10mm，满足要求。
表10示出了本实施例四提供的投影装置120中的各光学元件的光学参数。
由表10可知，镜头10中各个镜片均为球面镜。
S1为第一镜片11的像侧面，S2为第一镜片11的物侧面。S3为第二镜片12的像侧面，S4为第二镜片12的物侧面。S5为光阑102。S6为第三镜片13的像侧面，S7为第三镜片13的物侧面。S8为第四镜片14的像侧面，S9为第四镜片14的物侧面。S10为第五镜片15的像侧面，S11为第五镜片15的物侧面。S12为盖板玻璃103的像侧面，S13为盖板玻璃103的物侧面。OBJ为投影面，ImgH为成像面。
R为光学元件(如镜片或玻璃盖板等)在光轴对应位置处的曲率半径，Th为光学元件在光轴方向上的面厚度，Nd为d线照射至各光学元件的折射率，Vd为光学元件的阿贝数。
表11示出了本实施例四提供的镜头10的光学参数。
由表11可知，本申请实施例四所提供的镜头10兼具大光圈、大视场角的特性，且具有较小的后焦长度。
其中，Fno为镜头10的光圈，BFL为镜头10的后焦长度，TTL为镜头10的光学总长，R1为镜头10中最靠近像侧的镜片的像侧面的曲率半径，R2为镜头10中最靠近物侧的镜片的物侧面的曲率半径，f1为第一镜片11的焦距，f2为第二镜片12的焦距，f3为第三镜片13的焦距，f4为第四镜片14的焦距，f5为第五镜片15的焦距。
图17为图16中的镜头10的球色差图。在图17中，纵坐标表示的是归一化光瞳坐标，横坐标表示轴向方向上的像差，单位为毫米。在图17中，三条曲线分别对应波长为625nm的光、波长为550nm的光和波长为455nm的光经过本实施例的镜头10后的轴向像差曲线。从图17可以看出，在本实施例中，轴向像差控制在一个很小的范围内，得到较好的校正。
图18为图16中的镜头10的像散场曲图，图19为图16中的镜头10的畸变图。在图18中，S表示波长为525nm的光在子午像面的场曲值，T表示波长为525nm的光在弧矢像面的场曲值。在图19中，实线表示中心波长为525nm的光经过本实施例的镜头10的畸变值。在本实施例中，结合图18和图19可知，本实施例提供的镜头10将场曲和畸变控制在相应范围内，具有高的成像质量。
在本申请实施例的描述中，需要说明的是，除非另有明确的规定和限定，术语“安装”、“相连”、“连接”应作广义理解，例如，可以是固定连接，也可以是通过中间媒介间接相连，可以是两个元件内部的连通或者两个元件的相互作用关系。对于本领域的普通技术人员而言，可以根据具体情况理解上述术语在本申请实施例中的具体含义。
在本申请实施例或者暗示所指的装置或者元件必须具有特定的方位、以特定的方位构造和操作，因此不能理解为对本申请实施例的限制。在本申请实施例的描述中，“多个”的含义是两个或两个以上，除非是另有精确具体地规定。
本申请实施例的说明书和权利要求书及上述附图中的术语“第一”、“第二”、“第三”、“第四”等(如果存在)是用于区别类似的对象，而不必用于描述特定的顺序或先后次序。应该理解这样使用的数据在适当情况下可以互换，以便这里描述的本申请实施例的实施例例如能够以除了在这里图示或描述的那些以外的顺序实施。此外，术语“包括”和“具有”以及他们的任何变形，意图在于覆盖不排他的包含，例如，包含了一系列步骤或单元的过程、方法、系统、产品或设备不必限于清楚地列出的那些步骤或单元，而是可包括没有清楚地列出的或对于这些过程、方法、产品或设备固有的其它步骤或单元。
本文中的术语“多个”是指两个或两个以上。本文中术语“和/或”，仅仅是一种描述关联对象的关联关系，表示可以存在三种关系，例如，A和/或B，可以表示：单独存在A，同时存在A和B，单独存在B这三种情况。另外，本文中字符“/”，一般表示前后关联对象是一种“或”的关系；在公式中，字符“/”，表示前后关联对象是一种“相除”的关系。
可以理解的是，在本申请的实施例中涉及的各种数字编号仅为描述方便进行的区分，并不用来限制本申请的实施例的范围。
可以理解的是，在本申请的实施例中，上述各过程的序号的大小并不意味着执行顺序的先后，各过程的执行顺序应以其功能和内在逻辑确定，而不应对本申请的实施例的实施过程构成任何限定。

Claims (12)

  1. 一种镜头，其特征在于，包括透镜组和光阑；
    所述透镜组包括从像侧到物侧排列的至少五个镜片，所述透镜组中具有光焦度的所述镜片的数量为至少五个，所述透镜组中具有负光焦度的所述镜片的数量为至少一个；
    所述光阑包括沿像侧到物侧的方向相对设置的第一侧和第二侧，所述第一侧靠近所述像侧，所述第二侧靠近所述物侧，所述第一侧和所述第二侧中的至少一侧设置有所述镜片，其中：
    在所述第一侧设置有所述镜片时，位于所述第一侧且最靠近所述光阑的镜片具有负光焦度；和/或，
    在所述第二侧设置有所述镜片时，位于所述第二侧且最靠近所述光阑的镜片具有负光焦度。
  2. 根据权利要求1所述的镜头，其特征在于，所述镜头满足关系式：4.5mm＜BFL＜10mm，其中，所述BFL为所述镜头的后焦长度。
  3. 根据权利要求1或2所述的镜头，其特征在于，所述镜头满足关系式：30.02mm＜R1＜100mm，其中，所述R1为所述透镜组中最靠近所述像侧的所述镜片的像侧面的曲率半径。
  4. 根据权利要求1至3任一项所述的镜头，其特征在于，所述镜头满足关系式：15mm＜R2＜30mm，其中，所述R2为所述透镜组中最靠近所述物侧的所述镜片的物侧面的曲率半径。
  5. 根据权利要求1至4任一项所述的镜头，其特征在于，所述第一侧和所述第二侧均设置有所述镜片。
  6. 根据权利要求1至5任一项所述的镜头，其特征在于，所述透镜组中的至少一个所述镜片为具有光焦度的非球面镜。
  7. 根据权利要求1至5任一项所述的镜头，其特征在于，所述透镜组中具有光焦度的所有镜片均为球面镜。
  8. 根据权利要求1至7任一项所述的镜头，其特征在于，所述透镜组中具有负光焦度的所述镜片的数量为一个。
  9. 一种投影装置，其特征在于，包括显示单元和如权利要求1至8任一项所述的镜头；
    所述显示单元的显示面与所述镜头中最靠近物侧的所述镜片相对，所述显示单元被配置成形成显示图像，并将所述显示图像经过所述显示面传输至所述镜头。
  10. 根据权利要求9所述的投影装置，其特征在于，所述显示单元为微型发光二极管显示芯片、次毫米发光二极管显示芯片或薄膜场效应晶体管显示芯片。
  11. 一种车灯装置，其特征在于，包括外壳和如权利要求9或10所述的投影装置，所述投影装置的至少部分设置于所述外壳的内部。
  12. 一种交通工具，其特征在于，包括如权利要求11所述的车灯装置。
PCT/CN2025/100765 2024-07-03 2025-06-12 镜头、投影装置、车灯装置和交通工具 Pending WO2026007666A1 (zh)

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