In-vehicle projection optical system

Abstract

This invention discloses an in-vehicle projection optical system, comprising a first optical component, a light-transmitting substrate, and a second optical component arranged sequentially from the projection surface towards the light source along the optical axis. The first optical component includes a first lens, a second lens, and a third lens arranged sequentially, and an image is printed on the light-transmitting substrate. The second optical component includes a fourth lens, a fifth lens, and a light-emitting chip arranged sequentially. The optical power of the first lens is φ1, the optical power of the second lens is φ2, the optical power of the third lens is φ3, the optical power of the fourth lens is φ4, and the optical power of the fifth lens is φ5, wherein 0.06 < |φ1| < 0.07, 0.04 < |φ2| < 0.05, 0.03 < φ3 < 0.04, 0.02 < φ4 < 0.03, and 0.02 < φ5 < 0.3, so that the total optical length (TTL) of the optical system is ≤ 36 mm. The light-emitting chip emits light, which is converged and collimated by the fifth and fourth lenses to illuminate the light-transmitting substrate. The pattern on the light-transmitting substrate is revealed, and the image is projected onto a fixed position by the first optical component, thereby achieving clear imaging.

Description

Technical Field

[0001] This invention relates to the field of optical system technology, and particularly to vehicle-mounted projection optical systems. Background Technology

[0002] In recent years, with the rapid development of intelligent electric vehicles, various intelligent applications in vehicles have become more and more widespread. Existing in-vehicle projection display systems, such as the trunk using patterns projected by the projection system for intelligent recognition, car location, or opening and closing of the trunk, and the installation of welcome lights on the doors, have placed higher demands on the size of the projection optical system due to the limitation of installation space. Summary of the Invention

[0003] The main objective of this invention is to propose an in-vehicle projection optical system that is small in size and low in cost, so as to adapt to the installation space in the vehicle and meet the needs of consumers.

[0004] To achieve the above objectives, the present invention proposes an in-vehicle projection optical system, comprising a first optical component, a light-transmitting substrate, and a second optical component arranged sequentially from the projection surface to the light source along the optical axis. The first optical component includes a first lens, a second lens, and a third lens arranged sequentially. An image is printed on the light-transmitting substrate. The second optical component includes a fourth lens, a fifth lens, and a light-emitting chip arranged sequentially.

[0005] The optical power of the first lens is The optical power of the second lens is The optical power of the third lens is The optical power of the fourth lens is The optical power of the fifth lens is in, This ensures that the total optical length (TTL) of the optical system is less than or equal to 36 mm.

[0006] Optionally, the optical power of the first optical component is in,

[0007] Optionally, the optical power of the second optical component is in,

[0008] Optionally, the first lens, the second lens, the fourth lens, and the fifth lens are made of glass, and the light-transmitting substrate and the fourth lens are made of plastic.

[0009] Optionally, the first lens is configured as a spherical lens, and the optical power is positive;

[0010] The second lens is configured as a spherical lens with a negative optical power;

[0011] The third lens is configured as an aspherical lens with positive optical power;

[0012] The fourth lens is configured as an aspherical lens and has a positive optical power;

[0013] The fifth lens is configured as a spherical lens with positive optical power.

[0014] Optionally, the light-transmitting substrate is configured as a flat glass plate, and both end faces of the light-transmitting substrate opposite to each other in the optical axis direction are planar.

[0015] Optionally, the first lens is a biconvex lens, the second lens is a concave lens with its concave surface facing the projection surface, the third lens is a meniscus lens with its convex surface facing the light-emitting chip, the fourth lens is a convex lens with its convex surface facing the projection surface, and the fifth lens is a convex lens with its convex surface facing the projection surface.

[0016] Optionally, the third lens has a first surface facing the projection plane and a second surface facing away from the first surface, the central radius of curvature of the first surface being R1, and the central radius of curvature of the second surface being R2, wherein 1.2 <R1 / R2<1.3。

[0017] Optionally, the vehicle-mounted projection optical system further includes an aperture stop located on the side of the first lens facing away from the light-emitting chip.

[0018] Optionally, a filter is provided between the fifth lens and the light-emitting chip.

[0019] In the technical solution of this invention, the light-emitting chip emits light, which is converged and collimated by the fifth lens and the fourth lens to illuminate the light-transmitting substrate. The pattern on the light-transmitting substrate is revealed, and the image is projected onto a fixed position by the first optical component to form a projection surface, thereby achieving clear imaging and meeting consumer needs. By limiting the optical power values ​​of the first lens, the second lens, the third lens, the fourth lens, and the fifth lens, the total optical length (TTL) of the optical system is guaranteed to be ≤36mm after the lenses are debugged and assembled, thus achieving a smaller size compared to the prior art and adapting to vehicle installation space. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of an embodiment of the vehicle-mounted projection optical system provided by the present invention;

[0022] Figure 2 for Figure 1 A schematic diagram of the imaging MTF of the vehicle-mounted projection optical system;

[0023] Figure 3 for Figure 1 A schematic diagram of the distortion / field curvature of the vehicle-mounted projection optical system.

[0024] Explanation of icon numbers:

[0025] label name label name 100 In-vehicle projection optical system 2 Transparent substrate 1 First optical component 3 Second optical component 11 First lens 31 Fourth lens 12 Second lens 32 Fifth lens 13 Third lens 33 LED chip

[0026] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that if the embodiments of the present invention involve directional indication, the directional indication is only used to explain the relative positional relationship and movement of the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0029] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0030] In recent years, with the rapid development of intelligent electric vehicles, various intelligent applications in vehicles have become increasingly widespread. Due to the limitation of installation space, the projection optical system needs to be small in size. In response to the above requirements, this invention designs a miniaturized vehicle projection optical system that can be applied to vehicle projection display systems, such as intelligent recognition of patterns projected by the trunk through the projection system, for operations such as finding the car or opening and closing the trunk, and for use as welcome lights on the car doors. Figures 1 to 3 This is an embodiment of the vehicle-mounted projection optical system provided by the present invention.

[0031] Please refer to Figure 1 The vehicle-mounted projection optical system 100 includes a first optical component 1, a light-transmitting substrate 2, and a second optical component 3 arranged sequentially from the projection surface towards the light source along the optical axis. The first optical component 1 includes a first lens 11, a second lens 12, and a third lens 13 arranged sequentially. An image is printed on the light-transmitting substrate 2. The second optical component 3 includes a fourth lens 31, a fifth lens 32, and a light-emitting chip 33 arranged sequentially. The optical power of the first lens 11 is [missing information]. The optical power of the second lens 12 is The optical power of the third lens 13 is: The optical power of the fourth lens 31 is The optical power of the fifth lens 32 is in, This ensures that the total optical length (TTL) of the optical system is less than or equal to 36 mm.

[0032] In the technical solution of the present invention, the light-emitting chip 33 emits light as a light source. The light is converged and collimated by the fifth lens 32 and the fourth lens 31 to illuminate the light-transmitting substrate 2. The pattern on the light-transmitting substrate 2 is revealed and the image is projected onto a fixed position by the first optical component 1 to form a projection surface, thereby achieving clear imaging and meeting consumer needs. By limiting the optical power values ​​of the first lens 11, the second lens 12, the third lens 13, the fourth lens 31, and the fifth lens 32, the total optical length (TTL) of the optical system is guaranteed to be ≤36mm after the lenses are debugged and assembled. This achieves a smaller size compared to the prior art and is suitable for vehicle installation space.

[0033] Optical power is equal to the difference between the image-side beam convergence and the object-side beam convergence. It characterizes the ability of an optical system to deflect light rays. Since the first optical component 1 in this invention is formed by combining multiple lenses, in addition to the aforementioned limitation on the optical power of a single lens, in one embodiment, the optical power of the first optical component 1 is: in,

[0034] Furthermore, the second optical component 3 is also composed of multiple lenses; therefore, in another embodiment, the optical power of the second optical component 3 is... in,

[0035] In this embodiment, while limiting the optical power of a single lens, the overall optical power of the first optical component 1 and the second optical component 3 is also limited, thereby further ensuring that after the lenses are assembled, the total optical length TTL is ≤36mm under the condition of clear projection.

[0036] Considering the different functions of each lens, in this embodiment, the first lens 11, the second lens 12, the fourth lens 31, and the fifth lens 32 are made of glass, while the light-transmitting substrate 2 and the fourth lens 31 are made of plastic. This design does not affect the optical performance of the lenses, and at the same time, the use of a mixture of glass and plastic greatly reduces costs.

[0037] It is understood that in other embodiments, the materials of the first lens 11, the second lens 12, the fourth lens 31 and the fifth lens 32, the light-transmitting substrate 2 and the fourth lens 31 can all be glass.

[0038] Further, the first lens 11 is set as a spherical lens with a positive optical power, the second lens 12 is set as a spherical lens with a negative optical power, the third lens 13 is set as an aspherical lens with a positive optical power, the fourth lens 31 is set as an aspherical lens with a positive optical power, and the fifth lens 32 is set as a spherical lens with a positive optical power.

[0039] Furthermore, since the main function of the light-transmitting substrate 2 is to carry an image, the light-transmitting substrate 2 is set as flat glass, and both end faces of the light-transmitting substrate 2 opposite to each other in the optical axis direction are flat, and it does not need to have the ability to refract light, and only needs to ensure image display and light transmission.

[0040] Please refer to again Figure 1 , the first lens 11 is a biconvex lens, the second lens 12 is a concave lens with its concave surface facing the projection surface, the third lens 13 is a meniscus lens with its convex surface facing the light-emitting chip 33, the fourth lens 31 is a convex lens with its convex surface facing the projection surface, and the fifth lens 32 is a convex lens with its convex surface facing the projection surface. The light-emitting chip 33 emits light as a light source, the fifth lens 32 converges the angle of the light emitted by the light-emitting chip 33, the fourth lens 31 collimates the light so that the light can evenly illuminate the light-transmitting substrate 2, and then through the third lens 13, the second lens 12 and the first lens 11, the aberrations of the system are corrected in sequence, including distortion, resolution, chromatic aberration, etc., and finally a clear image is formed at a fixed position to form a projection surface.

[0041] It can be understood that the third lens 13 is a meniscus lens. The third lens 13 has a first surface facing the projection surface and a second surface opposite to the first surface. The central radius of curvature of the first surface is R1, and the central radius of curvature of the second surface is R2, where 1.2 < R1 / R2 < 1.3. Such a setting can ensure that the image is still clear when the system works at high temperature, so as not to be affected by the ambient temperature.

[0042] It should be noted that the surface shapes of the third lens 13 and the fourth lens 31 arranged as aspherical surfaces should satisfy the following equation:

[0043]

[0044] Among them, c is the curvature corresponding to the radius; y is the radial coordinate (whose unit is the same as the unit of the lens length); k is the conic section coefficient, and a1, a2, a3, a4, a5, a6, a7, a8 respectively represent the coefficients corresponding to each radial coordinate. The shape and size of the aspherical surfaces of the lens facing the projection surface and the light source can be set through the above parameters.

[0045] Specifically, when k < -1, the corresponding lens surface curve is a hyperbola; when k = -1, the corresponding lens surface curve is a parabola; when -1 < k < 0, the corresponding lens surface curve is an ellipse; when k = 0, the corresponding lens surface curve is a circle; and when k > 0, the corresponding lens surface curve is an oval.

[0046] The following explanation uses a projection system with a light source NA = 0.94 and an image circle diameter of 10.02 mm as an example.

[0047] The thickness of each lens and the radius of each surface are shown in Table 1 below, assuming the projection direction is towards the light source:

[0048] Table 1

[0049] Face number type radius R thickness Optical materials OBJ surface Infinity 500 STO standard 10.650 3.806 H-ZK3 S2 standard -40.591 2.038 S3 standard -19.575 0.8 H-ZF52A S4 standard Infinity 9.02 S5 aspherical -7.114 2.759 E48R S6 aspherical -5.581 9.693 S7 standard Infinity 0.7 B270 S8 standard Infinity 0.3 S9 standard 2.37943 3.5 E48R S10 standard Infinity 0.1 S11 standard 3.25 2.2 H-ZF6 S12 standard Infinity 0.2 IMA standard Infinity 0

[0050] The conic quadratic coefficients and aspherical coefficients corresponding to the two surfaces S5 and S6 of the aspherical third lens 13 and the two surfaces S9 and S10 of the aspherical fourth lens 31 are shown in Table 2 below:

[0051] Table 2

[0052]

[0053] Please refer to Figure 2 and Figure 3 The optical performance of the system can be evaluated based on the MTFD imaging curve and the distortion / field curvature curve. As can be seen from the above figures, the spherical aberration, field curvature and distortion in this embodiment can all be well corrected.

[0054] Furthermore, the vehicle-mounted projection optical system 100 also includes an aperture stop, which is located on the side of the first lens 11 facing away from the light-emitting chip 33, thereby limiting the size of the imaging range. The aperture stop can be the edge of the lens, the lens frame, or a specially designed perforated screen, etc., and is not limited here.

[0055] In addition, a filter is provided between the fifth lens 32 and the light-emitting chip 33, and the filter is used for wavelength separation.

[0056] It is understandable that, considering the different ambient light during the day and at night, the projection display effect is different. Therefore, the vehicle-mounted projection optical system 100 may also include a compensation light source that can be selectively turned on or off to compensate for the light source of the light-emitting chip 33.

[0057] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A vehicle-mounted projection optical system, characterized in that, The device includes a first optical component, a light-transmitting substrate, and a second optical component arranged sequentially from the projection surface of the light source along the optical axis. The first optical component includes a first lens with positive optical power, a second lens with negative optical power, and a third lens with positive optical power arranged sequentially. An image is printed on the light-transmitting substrate. The second optical component includes a fourth lens with positive optical power, a fifth lens with positive optical power, and a light-emitting chip arranged sequentially. The optical power of the first lens is φ1, the optical power of the second lens is φ2, the optical power of the third lens is φ3, the optical power of the fourth lens is φ4, and the optical power of the fifth lens is φ5, wherein 0.06 < |φ1| < 0.07, 0.04 < |φ2| < 0.05, 0.03 < φ3 < 0.04, 0.02 < φ4 < 0.03, and 0.02 < φ5 < 0.3, so that the total optical length TTL of the optical system is ≤ 36 mm; The vehicle-mounted projection optical system also includes an aperture stop, which is located on the side of the first lens that faces away from the light-emitting chip.

2. The vehicle-mounted projection optical system as described in claim 1, characterized in that, The optical power of the first optical component is φ100, where 0.04 < φ100 < 0.

05.

3. The vehicle-mounted projection optical system as described in claim 1 or 2, characterized in that, The optical power of the second optical component is φ300, where 0.03 < φ300 < 0.

04.

4. The vehicle-mounted projection optical system as described in claim 1, characterized in that, The first lens is configured as a spherical lens; The second lens is configured as a spherical lens; The third lens is configured as an aspherical lens; The fourth lens is configured as an aspherical lens; The fifth lens is configured as a spherical lens.

5. The vehicle-mounted projection optical system as described in claim 1 or 4, characterized in that, The light-transmitting substrate is made of flat glass, and both ends of the light-transmitting substrate facing each other in the optical axis direction are planar.

6. The vehicle-mounted projection optical system as described in claim 4, characterized in that, The first lens is a biconvex lens, the second lens is a concave lens with its concave surface facing the projection surface, the third lens is a meniscus lens with its convex surface facing the light-emitting chip, the fourth lens is a convex lens with its convex surface facing the projection surface, and the fifth lens is a convex lens with its convex surface facing the projection surface.

7. The vehicle-mounted projection optical system as described in claim 6, characterized in that, The third lens has a first surface facing the projection plane and a second surface facing away from the first surface. The central radius of curvature of the first surface is R1, and the central radius of curvature of the second surface is R2, where 1.2 <R1 / R2<1.3。 8. The vehicle-mounted projection optical system as described in claim 1, characterized in that, A filter is provided between the fifth lens and the light-emitting chip.

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