Vehicle, optical system and lens group thereof

Abstract

The invention discloses a vehicle, an optical system and a lens group thereof, the lens group comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are arranged from a light incident side to a light emergent side along an optical axis direction, the first lens has positive diopter, the second lens has positive diopter, the third lens has negative diopter, and the sixth lens has negative diopter. The fourth lens has positive diopter, the fifth lens has negative diopter, and the sixth lens has positive diopter. According to the lens group of the optical system provided by the embodiment of the invention, through the combination of the first lens to the sixth lens, the light emitting efficiency can be improved, and the modeling design is facilitated. In addition, diopter distribution is reasonable, sensitivity and performance are good, light rays emitted by the light source are shaped and projected by the lens set, high-pixel projection can be achieved, and the requirement for vehicle lamp illumination with pixels of ten thousand levels or above can be met.

Description

Technical Field

[0001] The present application relates to the field of vehicle technology, and in particular to a lens group of an optical system, an optical system and a vehicle. Background Art

[0002] With the development of automobile headlights and the increasing demand for headlights, the requirements for headlights are gradually increasing. The axial chromatic aberration, vertical chromatic aberration, MTF and field curvature distortion of the lens module are all crucial to its imaging quality. The imaging quality of automobile headlights in related technologies is relatively low. Summary of the invention

[0003] The present application aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present application is to provide a lens assembly of an optical system.

[0004] According to an embodiment of the present application, the lens group of the optical system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged from a light incident side to a light exit side along an optical axis, wherein the first lens has a positive refractive power, the second lens has a positive refractive power, the third lens has a negative refractive power, the fourth lens has a positive refractive power, the fifth lens has a negative refractive power, and the sixth lens has a positive refractive power.

[0005] According to the lens group of the optical system of the embodiment of the present application, the combination of the first lens to the sixth lens can improve the light extraction efficiency and facilitate the design. In addition, the diopter distribution in the present application is reasonable, and the sensitivity and performance have good performance, so that the light emitted by the light source is shaped and projected by the lens group, and high-pixel projection can be achieved, which can meet the lighting needs of car lights with more than 10,000 pixels.

[0006] In addition, the lens group of the optical system according to the above embodiment of the present application may also have the following additional technical features:

[0007] In some embodiments, the refractive index of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens is greater than 1.8.

[0008] In some embodiments, the Abbe number of the material of the first lens, the fifth lens and the sixth lens is greater than or equal to 40 and less than or equal to 50; and / or the Abbe number of the material of the second lens, the third lens and the fourth lens is greater than or equal to 20 and less than or equal to 40.

[0009] In some embodiments, a distance between two adjacent lenses of the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens is less than 8 mm.

[0010] In some embodiments, a stop is disposed on the light exit surface of the second lens.

[0011] In some embodiments, the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens are spherical lenses.

[0012] In some embodiments, the light incident surface of the first lens is concave, and the light emitting surface is convex; the light incident surface of the second lens is convex, and the light emitting surface is convex; the light incident surface of the third lens is concave, and the light emitting surface is concave; the light incident surface of the fourth lens is concave, and the light emitting surface is convex; the light incident surface of the fifth lens is concave, and the light emitting surface is concave; the light incident surface of the sixth lens is convex, and the light emitting surface is convex.

[0013] In some embodiments, at least a portion of the light emitting surface of the second lens is located inside the light incident surface of the third lens, and at least a portion of the light incident surface of the sixth lens is located inside the light emitting surface of the fifth lens.

[0014] In some embodiments, the light extraction efficiency of the lens group is higher than 30%.

[0015] According to an embodiment of the present application, the optical system includes a light source and the lens group of the aforementioned optical system, wherein the light source is disposed on the light incident side of the lens group.

[0016] In some embodiments, the light emitting surface of the light source is disposed at the focus of the first lens.

[0017] In some embodiments, the light source is configured as a planar light source perpendicular to the optical axis; and / or the light source is an LED light source or a laser light source; and / or the light emitted by the light source is white light.

[0018] The vehicle according to the embodiment of the present application includes a vehicle body and a lens group of the aforementioned optical system; or includes the aforementioned optical system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of a lens group of an optical system according to an embodiment of the present application.

[0020] Figure 2 It is a schematic diagram of vertical axis chromatic aberration of a lens group of an optical system according to an embodiment of the present application.

[0021] Figure 3 It is a schematic diagram of the axial chromatic aberration of a lens group of an optical system according to an embodiment of the present application.

[0022] Figure 4 It is a schematic diagram of the MTF of a lens group of an optical system according to an embodiment of the present application.

[0023] Figure 5 It is a schematic diagram of the field curvature distortion of a lens group of an optical system according to an embodiment of the present application.

[0024] Figure 6 It is a schematic diagram of an optical system according to an embodiment of the present application.

[0025] Figure 7 It is a beam trajectory diagram of an optical system according to an embodiment of the present application.

[0026] Figure 8 Schematic diagram of the MTF of an optical system according to an embodiment of the present application.

[0027] Reference numerals: optical system 100 , lens group 20 , first lens 21 , second lens 22 , third lens 23 , fourth lens 24 , fifth lens 25 , sixth lens 26 , light source 10 . DETAILED DESCRIPTION

[0028] The low beam headlight assembly in the related art has hundreds of pixels, which is mainly affected by size and materials, and the imaging quality cannot be improved. Moreover, the lens group in the related art is mainly for design purposes, and tolerance analysis has not been performed. Whether it can meet production needs remains to be verified. In addition, the structure volume of the low beam headlight assembly in the related art is relatively large in order to achieve the purpose of improving efficiency. For this reason, the present application provides a lens group of an optical system, which can achieve tens of thousands of pixels, improve the imaging quality, and has a compact structural design, high light output efficiency, and is conducive to modeling design. In addition, the design of the lens group in the present application is for the purpose of actual production, and the imaging quality can still be guaranteed after the tolerance analysis of the lens group.

[0029] This application aims to achieve mass production to meet human lighting needs, and has conducted tolerance analysis to meet production needs. The optical system of this application has a compact structure, which is conducive to modeling design, and at the same time ensures that the light output efficiency is higher than 30%. This application reduces axial chromatic aberration, vertical chromatic aberration, MTF, and field curvature distortion relative to the low beam headlight assembly in the related art through the design of lens materials, lens size, and relative position between lenses. The size of the blue-yellow edge is about 2 / 3 of the size of the 10,000-pixel module in the related art.

[0030] In order to facilitate the understanding of the technical solution, the technical terms involved in this application are explained below.

[0031] The optical axis is a ray of light that passes vertically through the center of an ideal lens. When light parallel to the optical axis enters a convex lens, the ideal convex lens should have all the light rays converge at one point behind the lens. The point where all the light rays converge is the focus.

[0032] Positive refractive power: The lens or lens group has a positive focal length and has the effect of converging light.

[0033] Negative refractive power: The lens or lens group has a negative focal length and has the effect of diverging light.

[0034] Abbe number: also known as dispersion coefficient, refers to the difference ratio of the refractive index of optical materials at different wavelengths, indicating the degree of dispersion of the material.

[0035] Chromatic aberration: When a beam of white light is emitted from a white object point to the optical system, after refraction through the optical series, the red, orange, yellow, green, cyan, blue, purple and other colored lights that make up the beam of white light cannot converge at the same point. That is, the white object point cannot form a white image point, but forms a colorful image spot. This imaging error is called chromatic aberration.

[0036] Axial chromatic aberration refers to the fact that the focal points of light beams of different wavelengths are located at different positions along the axis after passing through the lens. Its formation reason is the same as spherical aberration.

[0037] Vertical chromatic aberration refers to the situation when an object is imaged by light of different wavelengths through a lens. Due to the different magnifications, the image is formed at different heights. This aberration is called vertical chromatic aberration or magnification chromatic aberration.

[0038] MTF (Modulation Transfer Function) is an important indicator for measuring lens performance. The MTF curve is plotted by expressing the degree to which the lens reproduces the contrast of the subject on the image plane in terms of spatial frequency characteristics.

[0039] Field curvature is also called "image field curvature". When the lens has field curvature, the intersection of the entire light beam does not coincide with the ideal image point. Although a clear image point can be obtained at each specific point, the entire image plane is a curved surface. In this way, the entire image plane cannot be seen clearly at the same time during microscopic examination, which makes observation and photography difficult.

[0040] Distortion: The straight line outside the main axis in the plane of the object becomes a curve after being imaged by the optical system. The imaging error of this optical system is called distortion.

[0041] Aperture refers to an entity that limits the light beam in an optical system. It can be the edge of a lens, a frame, or a specially set screen with holes. Its function can be divided into two aspects: limiting the light beam or limiting the size of the field of view (imaging range).

[0042] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0043] like Figure 1The lens group 20 of the optical system 100 according to the embodiment of the present application includes a first lens 21, a second lens 22, a third lens 23, a fourth lens 24, a fifth lens 25 and a sixth lens 26 arranged from the light incident side to the light exit side along the optical axis. The first lens 21 has a positive refractive power, the second lens 22 has a positive refractive power, the third lens 23 has a negative refractive power, the fourth lens 24 has a positive refractive power, the fifth lens 25 has a negative refractive power, and the sixth lens 26 has a positive refractive power.

[0044] like Figure 7 , the light source 10 is arranged on the light incident side of the lens group 20, and the light enters the first lens 21 through the light incident surface of the first lens 21 along the optical axis direction, and is emitted from the light exit surface of the first lens 21 after being refracted by the first lens 21; then the light enters the second lens 22 through the light incident surface of the second lens 22, and is emitted from the light exit surface of the second lens 22 after being refracted by the second lens 22; then the light enters the third lens 23 through the light incident surface of the third lens 23, and is emitted from the light exit surface of the third lens 23 after being refracted by the third lens 23; then the light enters the fourth lens 24 through the light incident surface of the fourth lens 24, and is emitted from the light exit surface of the fourth lens 24 after being refracted by the fourth lens 24; then the light enters the fifth lens 25 through the light incident surface of the fifth lens 25, and is emitted from the light exit surface of the fifth lens 25 after being refracted by the fifth lens 25; then the light enters the sixth lens 26 through the light incident surface of the sixth lens 26, and is emitted from the light exit surface of the sixth lens 26 after being refracted by the sixth lens 26.

[0045] According to the lens group 20 of the optical system 100 of the embodiment of the present application, the combination of the first lens 21 to the sixth lens 26 can improve the light extraction efficiency and facilitate the design. In addition, the diopter distribution in the present application is reasonable, and the sensitivity and performance are well performed, so that the light emitted by the light source 10 is shaped and projected by the lens group 20, and high-pixel projection can be achieved, which can meet the lighting requirements of vehicle lights with more than 10,000 pixels. At the same time, through the reasonable setting of the light transmission diameter, the axial length of the entire optical system 100 increases less, and the overall volume is kept within a small range.

[0046] In some embodiments, the refractive index of the first lens 21, the second lens 22, the third lens 23, the fourth lens 24, the fifth lens 25, and the sixth lens 26 is greater than 1.8. By setting a higher refractive index, it is possible to facilitate the thinning of the lens group 20, thereby reducing the size of the lens group 20, and in addition, the imaging quality of the lens group 20 can be improved.

[0047] In addition, the Abbe number of the materials of the first lens 21, the fifth lens 25 and the sixth lens 26 is greater than or equal to 40 and less than or equal to 50; and / or the Abbe number of the materials of the second lens 22, the third lens 23 and the fourth lens 24 is greater than or equal to 20 and less than or equal to 40. The purpose of optimizing chromatic aberration and improving imaging quality can be achieved through the mutual coordination between the materials.

[0048] In some embodiments, the distance between two adjacent lenses of the first lens 21, the second lens 22, the third lens 23, the fourth lens 24, the fifth lens 25 and the sixth lens 26 in the present application is less than 8 mm. Thus, the size of the lens group 20 can be further reduced, thereby achieving the purpose of reducing the size of the lens group 20.

[0049] In some embodiments, a stop is provided on the light exiting surface of the second lens 22. Providing the stop on the fourth surface is beneficial for each lens to be close to the opening size.

[0050] In addition, the first lens 21 , the second lens 22 , the third lens 23 , the fourth lens 24 , the fifth lens 25 , and the sixth lens 26 are spherical lenses.

[0051] In some embodiments, the light incident surface of the first lens 21 is concave, and the light emitting surface is convex; the light incident surface of the second lens 22 is convex, and the light emitting surface is convex; the light incident surface of the third lens 23 is concave, and the light emitting surface is concave; the light incident surface of the fourth lens 24 is concave, and the light emitting surface is convex; the light incident surface of the fifth lens 25 is concave, and the light emitting surface is concave; the light incident surface of the sixth lens 26 is convex, and the light emitting surface is convex.

[0052] At least a portion of the light exiting surface of the second lens 22 is located inside the light incident surface of the third lens 23, and at least a portion of the light incident surface of the sixth lens 26 is located inside the light exiting surface of the fifth lens 25. This is beneficial to further reduce the size of the lens group 20.

[0053] In some embodiments, the light extraction efficiency of the lens assembly 20 is higher than 30%.

[0054] The lens group 20 of the present application includes a first lens 21 , a second lens 22 , a third lens 23 , a fourth lens 24 , a fifth lens 25 and a sixth lens 26 . The lens group 20 can be used to project a light spot emitted by the light source 10 to a distant place. Figure 1 Each lens from left to right has been designed, and each lens is a spherical lens. Due to the compact structure of the design, the refractive index of the material is required to be high, and the refractive index of all materials is greater than 1.8. The Abbe number of the material of the first, fifth, and sixth lenses is between 40-50, and the Abbe number of the material of the second, third, and fourth lenses is between 20-40. The purpose of optimizing chromatic aberration and improving imaging quality can be achieved through the mutual coordination of the materials.

[0055] Combined with the above lens parameters of the present application, calculation is performed according to the PW method, wherein:

[0056] According to the above calculation results, it can be seen that the aberration of the above lens group in the present application can be corrected very well. Among them, P and W in the pw method are used to select the parameters of the optical glass pair. According to the lens requirements (mainly double-focus lens), the P value and W value can be obtained by calculation, k is the number of lens groups, n is the refractive index, and u is the aperture angle. The lens group of the present application optimizes the Seidel number to the minimum through the pw method to improve the imaging quality.

[0057] For low beam, a clear cut-off line can make the lighting distance farther. The vertical axis chromatic aberration, axial chromatic aberration, MTF, and field curvature distortion of the lens group 20 determine the imaging quality of the lens group 20. Figure 2 The vertical axis chromatic aberration of the light projected by the lens group 20 of some embodiments of the present application is shown. Figure 3 The figure shows the axial chromatic aberration of the light projected by the lens group 20 according to some embodiments of the present application. Figure 4 The MTF of the light projected by the lens group 20 according to some embodiments of the present application is shown. Figure 5 The figure shows the field curvature distortion of the light projected by the lens group 20 of some embodiments of the present application. It can be seen from the above figures that after applying the lens group 20 in the present application, the imaging quality is improved and the yellow-blue edge is improved.

[0058] like Figure 6 According to the optical system 100 of the embodiment of the present application, it includes a light source 10 and the lens group 20 of the optical system 100, and the light source 10 is arranged on the light incident side of the lens group 20. The light of the light source 10 can be emitted through the lens to meet the needs of lighting or projection.

[0059] The present application includes a light source 10 and a lens group 20. The light source 10 can be either an LED or a laser. A spherical lens group 20 is used. The lens group 20 can include six spherical lenses. The present application emits white light from a light source 10 that conforms to the national standard color coordinates, and redistributes the light field through the lens group 20 to achieve the lighting function.

[0060] Optionally, the light emitting surface of the light source 10 is set at the focus of the first lens 21. Assuming the focal length of the lens group 20 is F, the size of the light source 10 is x, and the divergence angle of the light spot emitted by the lens group 20 to the light source 10 is 2α, wherein F, x and α satisfy: F = x / tanα

[0061] The light emitted from the light emitting surface of the light source 10 passes through the lens group 20 and is tested on a test screen at a distance of 25 m according to regulatory requirements. The focal length of the lens can be calculated according to the size of the light source 10 and the divergence angle required by regulations.

[0062] In some embodiments, the light source 10 is a plane light source 10 perpendicular to the optical axis; and / or, the light source 10 is an LED light source 10 or a laser light source 10; and / or, the light emitted by the light source 10 is white light. The light source 10 can be an LED white light, or a laser light source 10 that is processed to emit white light. The light emitting surface of the light source 10 should be small, and the light energy density should be large, and the light emitting surface of the light source 10 should be placed at the focus of the lens group 20.

[0063] Combined with the above-mentioned embodiments, this application is user-oriented, and optical design is carried out based on mass production. When designing the lens group 20, tolerance analysis is performed. When distinguishing images with MTF greater than 0.2, the human eye will have a clear perception, and when MTF is less than 0.2, the human eye will see the image blurry. The assembly and processing accuracy will affect the actual imaging effect of the lens. Through Monte Carlo random analysis, the yield is high during the assembly and processing process, which is suitable for production. Figure 8 The MTF of the light projected by the optical system 100 in this application is shown.

[0064] The vehicle according to the embodiment of the present application includes a vehicle body and the lens group 20 of the aforementioned optical system 100 ; or includes the aforementioned optical system 100 .

[0065] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0066] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0067] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0069] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A lens assembly of an optical system, characterized in that: The invention comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens arranged from a light incident side to a light exit side along an optical axis, wherein the first lens has a positive refractive power, the second lens has a positive refractive power, the third lens has a negative refractive power, the fourth lens has a positive refractive power, the fifth lens has a negative refractive power, and the sixth lens has a positive refractive power.

2. The lens assembly according to claim 1, characterized in that: The refractive indexes of the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens are greater than 1.

8.

3. The lens assembly according to claim 1 or 2, characterized in that: The Abbe number of materials of the first lens, the fifth lens and the sixth lens is greater than or equal to 40 and less than or equal to 50; and / or the Abbe number of materials of the second lens, the third lens and the fourth lens is greater than or equal to 20 and less than or equal to 40.

4. The lens assembly according to claim 1, characterized in that: Among the first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens, a distance between two adjacent lenses is less than 8 mm.

5. The lens assembly according to claim 1, characterized in that: The light exiting surface of the second lens is provided with an aperture.

6. The lens assembly according to claim 1, characterized in that: The first lens, the second lens, the third lens, the fourth lens, the fifth lens and the sixth lens are spherical lenses.

7. The lens assembly according to claim 1, characterized in that: The light incident surface of the first lens is concave, and the light exiting surface is convex; the light incident surface of the second lens is convex, and the light exiting surface is convex; the light incident surface of the third lens is concave, and the light exiting surface is concave; the light incident surface of the fourth lens is concave, and the light exiting surface is convex; the light incident surface of the fifth lens is concave, and the light exiting surface is concave; the light incident surface of the sixth lens is convex, and the light exiting surface is convex.

8. The lens assembly according to claim 1, characterized in that: At least a portion of a light emitting surface of the second lens is located inside a light incident surface of the third lens, and at least a portion of a light incident surface of the sixth lens is located inside a light emitting surface of the fifth lens.

9. The lens assembly according to claim 1, characterized in that: The light extraction efficiency of the lens group is higher than 30%.

10. An optical system, characterized in that: A lens group comprising a light source and the optical system according to any one of claims 1 to 9, wherein the light source is arranged on the light incident side of the lens group.

11. The optical system according to claim 10, characterized in that The light emitting surface of the light source is arranged at the focus of the first lens.

12. The optical system according to claim 10, characterized in that The light source is set as a planar light source perpendicular to the optical axis; and / or, the light source is an LED light source or a laser light source; and / or, the light emitted by the light source is white light.

13. A vehicle, characterized in that: A lens group comprising a vehicle body and the optical system according to any one of claims 1 to 9; or an optical system according to any one of claims 10 to 12.

Images