Wide field-of-view zoom lens for vehicle headlight inspection

Abstract

This invention discloses a large field-of-view zoom lens for vehicle headlight inspection, comprising an aperture stop, a first lens, a second lens, a third lens, and a fourth lens arranged sequentially along the optical axis from the object side to the image side. The first lens is a positive lens, the second lens is a negative lens, the third lens is a positive lens, and the fourth lens is a positive lens. Each of the first, second, third, and fourth lenses includes both an object-side surface and an image-side surface. This large field-of-view zoom lens for vehicle headlight inspection is designed to be compatible with large field-of-view pixel headlights, reducing the space required for testing and improving measurement accuracy while meeting the mass production testing requirements of large field-of-view pixel headlights.

Description

Technical Field

[0001] This invention relates to the technical field of optical systems, and in particular to a large field-of-view zoom lens for vehicle headlight detection. Background Technology

[0002] In existing technologies, there are two main methods for detecting high and low beam headlights:

[0003] 1. Direct testing method: The light pattern is directly shone on the screen; this testing method is suitable for pixel headlights, but the direct testing method of shone the light pattern on the screen at a distance requires a large testing space, which is not conducive to mass production testing needs.

[0004] II. Indirect Detection Method: The light pattern is projected onto the screen after being shortened by a lens. This method is suitable for pixel headlights, but for indirect detection, although the shortened lenses currently have a large aperture design, the image clarity is not high, and it can only test high and low beam headlights. Indirect testing methods using a lens device require the lens device to be compatible with the headlight module under test; otherwise, the measurement accuracy will be affected. Currently, lens devices compatible with high and low beam headlights are relatively mature, but those compatible with wide-angle pixel headlights are relatively few. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0006] To address this, the present invention proposes a large field-of-view zoom lens for vehicle headlight inspection, which meets the mass production inspection requirements of large field-of-view pixel headlights, reduces the space required for testing, and improves measurement accuracy.

[0007] A large field-of-view zoom lens for vehicle headlight detection according to an embodiment of the present invention includes an aperture stop, a first lens, a second lens, a third lens, and a fourth lens arranged sequentially from the object side to the image side along the optical axis. The first lens is a positive lens, the second lens is a negative lens, the third lens is a positive lens, and the fourth lens is a positive lens. The first lens includes a first object-side surface and a first image-side surface; the second lens includes a second object-side surface and a second image-side surface; the third lens includes a third object-side surface and a third image-side surface; and the fourth lens includes a fourth object-side surface and a fourth image-side surface.

[0008] The beneficial effects of this invention are: it adopts a four-element spherical lens design, with mature processing technology and stable materials, resulting in excellent manufacturability and reliability; the reasonable combination of positive and negative lenses allows the shortened lens to meet the requirements of a large field of view while possessing small image distortion and high image resolution; furthermore, this invention has excellent compatibility with large field-of-view pixel headlights, enabling accurate measurement of the optical performance of the lamps; and by using the shortened lens of this invention in the testing system to reduce the testing distance and testing area, it can save testing space and improve mass production testing capabilities.

[0009] According to one embodiment of the present invention, the first object-side surface of the first lens is convex or concave, and the first image-side surface of the first lens is convex.

[0010] According to one embodiment of the present invention, the second object-side surface of the second lens is concave, and the second image-side surface of the second lens is either concave or convex.

[0011] According to one embodiment of the present invention, the third object-side surface of the third lens is a convex surface, and the third image-side surface of the third lens is a concave surface.

[0012] According to one embodiment of the present invention, the fourth object-side surface of the fourth lens is concave, and the fourth image-side surface of the fourth lens is convex.

[0013] According to one embodiment of the present invention, the second lens and the third lens are two independent lenses or cemented doublet lenses.

[0014] According to one embodiment of the present invention, the first lens, the second lens, the third lens and the fourth lens are all spherical in surface type and the lens material is glass.

[0015] According to one embodiment of the present invention, the material of at least one of the second lens and the third lens satisfies the following condition: Abbe number abv ≤ 35.

[0016] According to one embodiment of the present invention, the focal length of the first lens is set to f1, and the focal length of the fourth lens is set to f4. Then the focal lengths of the first lens and the fourth lens satisfy: 3f1≤f4≤7f1.

[0017] According to one embodiment of the present invention, the shortest distance between the aperture stop and the first object side surface of the first lens is set to D, then D satisfies: D≥20mm.

[0018] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. 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 recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0023] Figure 3 This is a schematic diagram of the structure of Embodiment 3 of the present invention.

[0024] The labels in the figure are: a, optical axis; Stop, aperture stop; L1, first lens; L2, second lens; L3, third lens; L4, fourth lens; S1, first object side; S2, first image side; S3, second object side; S4, second image side; S5, third object side; S6, third image side; S7, fourth object side; S8, fourth image side. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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 some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In the description of this invention, it should be understood that the terms "one side", "the other side", "both sides", "between", "middle", "upper end", "lower end", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0027] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "set" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The following describes in detail, with reference to the accompanying drawings, a large field-of-view zoom lens for vehicle headlight detection according to an embodiment of the present invention.

[0029] See Figure 1 , Figure 2 and Figure 3 The present invention relates to a large field-of-view zoom lens for vehicle headlight detection. The zoom lens has a four-element structure, including an aperture stop (Stop), a first lens (L1), a second lens (L2), a third lens (L3), and a fourth lens (L4) arranged sequentially from the object side to the image side along the optical axis a. The first lens (L1) is a positive lens, the second lens (L2) is a negative lens, the third lens (L3) is a positive lens, and the fourth lens (L4) is a positive lens. The optical power of the first lens (L1), the second lens (L2), the third lens (L3), and the fourth lens (L4) is arranged in a positive-negative-positive-positive pattern. The first lens (L1) includes a first object-side surface (S1) and a first image-side surface (S2). The first lens (L1), the second lens (L2), the third lens (L3), and the fourth lens (L4) all include an object-side surface and an image-side surface. Specifically, the second lens (L2) includes a second object-side surface (S3) and a second image-side surface (S4); the third lens (L3) includes a third object-side surface (S5) and a third image-side surface (S6); and the fourth lens (L4) includes a fourth object-side surface (S7) and a fourth image-side surface (S8). The zoom lens of this invention can clearly project the object-side virtual image onto the image-side screen, thereby reducing the test distance and shrinking the test area in pixel headlight detection.

[0030] Preferably, the first object-side surface S1 of the first lens L1 is convex or concave, and the first image-side surface S2 of the first lens L1 is convex.

[0031] Preferably, the second object-side surface S3 of the second lens L2 is concave, and the second image-side surface S4 of the second lens L2 is either concave or convex.

[0032] Preferably, the third object-side surface S5 of the third lens L3 is convex, and the third image-side surface S6 of the third lens L3 is concave.

[0033] Preferably, the fourth object-side surface S7 of the fourth lens L4 is concave, and the fourth image-side surface S8 of the fourth lens L4 is convex.

[0034] Preferably, the second lens L2 and the third lens L3 are two independent lenses or cemented doublet lenses.

[0035] Preferably, the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 are all spherical and made of glass. That is, the surface type of the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 are all spherical, and the first lens L1, the second lens L2, the third lens L3, and the fourth lens L4 are all made of glass. By combining positive and negative lenses and matching lens materials, the distortion and aberration of the entire lens can be reasonably corrected.

[0036] Preferably, the material of at least one of the second lens L2 and the third lens L3 satisfies the following condition: Abbe number abv ≤ 35.

[0037] Preferably, the field of view of the zoom lens is set to FOV, then FOV satisfies: FOV≤60°.

[0038] Preferably, the focal length of the first lens L1 is set to f1, and the focal length of the fourth lens L4 is set to f4. Then the focal lengths of the first lens L1 and the fourth lens L4 satisfy: 3f1≤f4≤7f1.

[0039] Preferably, the shortest distance between the aperture stop Stop and the first object side surface S1 of the first lens L1 is set as D, then D satisfies: D≥20mm.

[0040] The large field-of-view zoom lens for vehicle headlight testing of this invention adopts a four-element spherical lens design, with mature processing technology and stable materials, resulting in excellent manufacturability and reliability. The reasonable combination of positive and negative lenses allows the zoom lens to achieve a large field of view while possessing minimal image distortion and high image resolution. Furthermore, this invention has excellent compatibility with large field-of-view pixel headlights, enabling accurate measurement of the optical performance of the luminaire. Using the zoom lens of this invention in the testing system reduces the testing distance and testing area, saving testing space and improving mass production testing capabilities.

[0041] Example 1

[0042] See Figure 1 The large field-of-view zoom lens for vehicle headlight detection of the present invention comprises a first lens L1 (positive lens), a second lens L2 (negative lens), a third lens L3 (positive meniscus lens), and a fourth lens L4 (positive meniscus lens). The first object-side surface S1 and the first image-side surface S2 of the first lens L1 are convex. The second object-side surface S3 and the second image-side surface S4 of the second lens L2 are concave. The third object-side surface S5 and the third image-side surface S6 of the third lens L3 are convex. The fourth object-side surface S7 and the fourth image-side surface S8 of the fourth lens L4 are concave. The second lens L2 and the third lens L3 are two independent lenses. The parameters of the large field-of-view zoom lens of Embodiment 1 are shown in Table 1 below.

[0043]

Table 1

[0044]

[0045] This wide field-of-view zoom lens for vehicle headlight testing is designed to be compatible with wide field-of-view pixel headlights. It reduces the space required for testing and improves measurement accuracy while meeting the mass production testing requirements of wide field-of-view pixel headlights.

[0046] Example 2

[0047] See Figure 2 The large field-of-view zoom lens for vehicle headlight detection of the present invention comprises a first lens L1 (positive lens), a second lens L2 (negative lens), a third lens L3 (positive meniscus lens), and a fourth lens L4 (positive meniscus lens). The first object-side surface S1 of the first lens L1 is concave, and the first image-side surface S2 of the first lens L1 is convex. The second object-side surface S3 of the second lens L2 is concave, and the second image-side surface S4 of the second lens L2 is convex. The third object-side surface S5 of the third lens L3 is convex, and the third image-side surface S6 of the third lens L3 is concave. The fourth object-side surface S7 of the fourth lens L4 is concave, and the fourth image-side surface S8 of the fourth lens L4 is convex. The second lens L2 and the third lens L3 are two independent lenses. The parameters of the large field-of-view zoom lens of Embodiment 2 are shown in Table 2 below.

[0048]

Table 2

[0049]

[0050] This wide field-of-view zoom lens for vehicle headlight testing is designed to be compatible with wide field-of-view pixel headlights. It reduces the space required for testing and improves measurement accuracy while meeting the mass production testing requirements of wide field-of-view pixel headlights.

[0051] Example 3

[0052] See Figure 3 The large field-of-view zoom lens for vehicle headlight detection of the present invention comprises a first lens L1 (positive lens), a second lens L2 (negative lens), a third lens L3 (positive meniscus lens), and a fourth lens L4 (positive meniscus lens). The first object-side surface S1 and the first image-side surface S2 of the first lens L1 are convex. The second object-side surface S3 and the second image-side surface S4 of the second lens L2 are concave. The third object-side surface S5 and the third image-side surface S6 of the third lens L3 are convex. The fourth object-side surface S7 and the fourth image-side surface S8 of the fourth lens L4 are concave. The second lens L2 and the third lens L3 are cemented doublet lenses. The parameters of the large field-of-view zoom lens of Embodiment 3 are shown in Table 3 below.

[0053]

Table 3

[0054]

[0055]

[0056] This wide field-of-view zoom lens for vehicle headlight testing is designed to be compatible with wide field-of-view pixel headlights. It reduces the space required for testing and improves measurement accuracy while meeting the mass production testing requirements of wide field-of-view pixel headlights.

[0057] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A large field-of-view zoom lens for vehicle headlight detection, characterized in that: The lens has a total of four lenses, including an aperture stop, a first lens (L1), a second lens (L2), a third lens (L3), and a fourth lens (L4) arranged sequentially from the object side to the image side along the optical axis (a). The first lens (L1) is a positive lens, the second lens (L2) is a negative lens, the third lens (L3) is a positive lens, and the fourth lens (L4) is a positive lens. The first lens (L1) includes a first object-side surface (S1) and a first image-side surface (S2); the second lens (L2) includes a second object-side surface (S3) and a second image-side surface (S4); the third lens (L3) includes a third object-side surface (S5) and a third image-side surface (S6); and the fourth lens (L4) includes a fourth object-side surface (S7) and a fourth image-side surface (S8). The first object-side surface (S1) of the first lens (L1) is convex or concave, and the first image-side surface (S2) of the first lens (L1) is convex. The second object-side surface (S3) of the second lens (L2) is concave, and the second image-side surface (S4) of the second lens (L2) is either concave or convex. The third object-side surface (S5) of the third lens (L3) is convex, and the third image-side surface (S6) of the third lens (L3) is concave. The fourth object-side surface (S7) of the fourth lens (L4) is concave, and the fourth image-side surface (S8) of the fourth lens (L4) is convex. The optical parameters of this lens are shown in the table below: or, or, 。

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