Equipment monitoring wide-angle lens

Abstract

The utility model relates to a wide-angle lens for monitoring equipment, which comprises a diaphragm, and further comprises a first lens, a second lens, a third lens, a fourth lens and a balsaming lens group which are sequentially and coaxially arranged between an object plane and an image plane, the balsaming lens group comprises a fifth lens and a sixth lens, and the diaphragm is positioned between the third lens and the fourth lens. The focal length ranges of the first lens, the second lens, the third lens, the fourth lens and the balsaming lens group are respectively 0.5 lt; f1 / flt; 2.5); 3lt; f2 / flt; 5; 2.5 lt, 2.5 lt; f3 / flt; 4; 1lt; f4 / flt; 3.5); f < 5-6 > is 4 lt; f < 5-6 > / f < lt >; 6.5); f is the focal length of the whole optical system of the equipment monitoring wide-angle lens, and f1, f2, f3, f4 and f5-6 are the focal lengths of the first lens, the second lens, the third lens, the fourth lens and the balsaming lens group respectively; the device is reasonable in design, compact in structure and convenient to use.

Description

Technical Field

[0001] This utility model relates to a wide-angle lens for equipment monitoring and belongs to the field of optical imaging technology. Background Technology

[0002] Automated or semi-automated production equipment is increasingly being used in the field of optics. To facilitate the traceability of the production process and real-time monitoring of the equipment's operating status, wide-angle monitoring lenses are often installed inside the equipment.

[0003] The monitoring wide-angle lens inside the device is an optical system that can clearly and efficiently image light signals onto a chip. Due to its characteristics of large field of view and high pixel count, the monitoring wide-angle lens is often widely used in monitoring, vehicle-mounted, and automated equipment.

[0004] Existing wide-angle lenses suffer from low pixel count and small field of view, making it impossible to clearly and effectively display the complete movement of equipment within a large field of view. They can no longer meet the requirements for large field of view and efficient real-time monitoring during equipment operation. Therefore, there is an urgent need to design a small-sized wide-angle lens with high imaging quality for equipment monitoring. The optical structure for monitoring the operation process within optical automatic inspection equipment has become a research focus for engineers. Utility Model Content

[0005] In general, the technical problem this invention aims to solve is to provide a wide-angle lens for equipment monitoring. This invention features excellent aberration characteristics, achieving a 163-degree field of view and 5MP high-resolution imaging. It is less prone to blind spots during use, has good light-gathering effect, and produces clear and bright images, thus facilitating more effective information transmission. Especially when used as a monitoring lens, it can capture high-definition, high-resolution images over a wide field of view. Furthermore, this invention has a simple and compact structure and high imaging quality, making it suitable for application in equipment monitoring technology, thereby improving the level of detail monitoring.

[0006] To solve the above problems, the technical solution adopted by this utility model is as follows:

[0007] To solve the above technical problems, the technical solution adopted by this utility model is: a wide-angle lens for equipment monitoring, including an aperture stop, and a first lens, a second lens, a third lens, a fourth lens, and a cemented lens group arranged coaxially between the object plane and the image plane in sequence. The cemented lens group includes a fifth lens and a sixth lens, and the aperture stop is located between the third lens and the fourth lens.

[0008] Further, the focal length ranges of the first lens, the second lens, the third lens, the fourth lens, and the cemented lens group are respectively: 0.5 < |f1| / f < 2.5; 3 < |f2| / f < 5; 2.5 < |f3| / f < 4; 1 < |f4| / f < 3.5; for f5-6, 4 < |f5-6| / f < 6.5;

[0009] Among them, f is the focal length of the entire optical system of the device monitoring wide-angle lens, and f1, f2, f3, f4, and f5-6 are the focal lengths of the first lens, the second lens, the third lens, the fourth lens, and the cemented lens group respectively.

[0010] Further, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, and the sixth lens are all glass spherical lenses;

[0011] Among them, the first lens, the second lens, and the third lens are all meniscus lenses, the fourth lens is a biconvex lens, and the cemented lens group is composed of the fifth lens and the sixth lens: the fifth lens is a biconvex lens and the sixth lens is a meniscus lens.

[0012] Further, the overall optical length of the device monitoring wide-angle lens is less than or equal to 27.5 mm.

[0013] Further, the refractive index Nd of the first lens is 1.5 < Nd < 1.7, and the dispersion rate Vd is 40 < Vd < 60;

[0014] The refractive index Nd of the second lens is 1.9 < Nd < 2.1, and the dispersion rate Vd is 20 < Vd < 30;

[0015] The refractive index Nd of the third lens is 1.7 < Nd < 1.9, and the dispersion rate Vd is 25 < Vd < 35;

[0016] The refractive index Nd of the fourth lens is 1.8 < Nd < 2.0, and the dispersion rate Vd is 40 < Vd < 50;

[0017] The refractive index Nd of the fifth lens is 1.5 < Nd < 1.7, and the dispersion rate Vd is 50 < Vd < 60;

[0018] The refractive index Nd of the sixth lens is 1.8 < Nd < 2.0, and the dispersion rate Vd is 15 < Vd < 25;

[0019] Further, the maximum outer diameter of the optical structure is less than or equal to 15 mm.

[0020] Further, the aperture number of the device monitoring wide-angle lens is less than or equal to 2.5.

[0021] ​

[0022] As part of the overall structural protection, a device monitoring wide-angle lens also includes a lens barrel with a first group of lenses, an aperture, and a second group of lenses.

[0023] A central through-hole is provided in the microscope tube;

[0024] A spacer B, serving as an aperture, is provided in the central through-hole section;

[0025] A spacer C is provided to the right of spacer B;

[0026] A spacer A is located to the left of spacer B;

[0027] A pressure ring is provided at the left end of the microscope tube;

[0028] An inner pressure platform is provided at the left end of the pressure ring, and a left inner stop is provided at the left end of the lens barrel;

[0029] A right locking part is provided at the right end of the through hole;

[0030] Spacer A is set in the left inner stop;

[0031] Lens No. 1 is positioned between the inner pressure stage and spacer A;

[0032] The left end of the second lens abuts against the right end face of spacer A, and the right end of spacer A is located in the middle of the through hole.

[0033] Lens No. 3 is positioned between lens No. 2 and spacer B;

[0034] Spacer C is located between lens number four and lens number five.

[0035] As a further improvement to the above technical solution:

[0036] The right end of lens number six abuts against the right locking part;

[0037] A right-end stop is provided at the right end of the right-side locking part;

[0038] The outer wall of the lens barrel is provided with threads that connect to the threaded part of the pressure ring;

[0039] An inner step is provided between the threaded part of the pressure ring and the inner pressure plate part.

[0040] Effective pixel calculation formula: pixel = 4 * S * (MTF cutoff frequency)², where S represents the chip area.

[0041] This invention can produce a 5-megapixel optical imaging lens with good aberration characteristics, high image resolution, and high definition using only six glass spherical lenses. It is less prone to light spillage during the light-gathering process, resulting in a clear image plane, which is more conducive to the complete and effective transmission of information, especially for use as a surveillance lens. In addition, this invention has a simple and compact structure and high resolution, achieving the goals of equipment monitoring, high image quality, and a wide field of view, which is beneficial for the application of the lens in the field of security monitoring.

[0042] This utility model is reasonably designed, low in cost, sturdy and durable, safe and reliable, simple to operate, time-saving and labor-saving, cost-saving, compact in structure and easy to use. Attached Figure Description

[0043] Figure 1 This is a system composition diagram of this utility model.

[0044] Figure 2 This is a diagram showing the light entry path of this utility model.

[0045] Figure 3 This is a schematic diagram of the MTF resolution curve of this utility model.

[0046] Figure 4 This is a schematic diagram of the astigmatic curve structure of this utility model.

[0047] Figure 5 This is a distorted schematic diagram of the present invention.

[0048] Figure 6 This is a schematic diagram of the relative illumination of this utility model.

[0049] Figure 7 This is a schematic diagram of the dot array of this utility model.

[0050] Figure 8 This is a schematic diagram of the device structure of this utility model.

[0051] The components are as follows: 1. Lens No. 1; 2. Lens No. 2; 3. Lens No. 3; 4. Lens No. 4; 5. Lens No. 5; 6. Lens No. 6; 7. Object plane; 8. Aperture; 9. Image plane; 11. Pressure ring; 12. Lens tube; 13. Spacer A; 14. Spacer B; 15. Spacer C; 16. Inner step section; 17. Inner pressure stage section; 18. Left inner stop; 19. Central through hole section; 20. Right locking section; 21. Right end stop. Detailed Implementation

[0052] like Figure 1-8 The device in this embodiment monitors a wide-angle lens, including an aperture stop 8, such as... Figure 1 As shown, lens 1, lens 2, lens 3, lens 4, lens 5, and lens 6 are set in sequence.

[0053] Lens 1, Lens 2, and Lens 3 are located to the left of aperture 8, while Lens 4, Lens 5, and Lens 6 are located to the right.

[0054] Lens 1, Lens 2, Lens 3, Lens 4, Lens 5, and Lens 6 are arranged coaxially from the object plane 7 to the image plane 9 in sequence;

[0055] Among them, lens 1 is a meniscus lens with negative optical power; lens 2 is a meniscus lens with positive optical power, used to converge light; lens 3 is a meniscus lens with negative optical power, which has the function of correcting the field area and converging and transmitting light to the aperture; lens 4 is a biconvex lens with positive optical power, used to correct field curvature and converge and transmit light to a cemented lens group with positive optical power, wherein the cemented lens group consists of lens 5 and lens 6, which are used to correct chromatic aberration of the optical system, converge light and converge it to the image plane 9.

[0056] Lens 1, Lens 2, Lens 3, Lens 4, Lens 5, and Lens 6 all use glass spherical lenses, which have good aberration characteristics, good imaging quality, and can also effectively reduce processing difficulty and production costs.

[0057] like Figure 8 In this embodiment, the device monitors a wide-angle lens, with a first lens group, an aperture 8, and a second lens group, all equipped with a lens barrel 12; thus achieving overall assembly.

[0058] A central through-hole 19 is provided in the lens barrel 12 to facilitate the mounting of the main lens;

[0059] A spacer B14, serving as an aperture 8, is provided in the central through hole 19; a spacer C15 is provided to the right of spacer B14; and a spacer A13 is provided to the left of spacer B14, thereby achieving axis fixation and position adjustment.

[0060] A pressure ring 11 is provided at the left end of the lens barrel 12 to achieve overall assembly and fixation.

[0061] An inner pressure stage 17 is provided at the left end of the pressure ring 11, and a left inner stop 18 is provided at the left end of the lens barrel 12; this achieves large-end fixation, increases the area for light collection, and reduces light loss.

[0062] A right locking part 20 is provided at the right end of the through hole part 19; to realize the fixing of the lens and the output of light.

[0063] Spacer A13 is set in the left inner stop 18;

[0064] Lens 1 is positioned between the inner pressure stage 17 and the spacer A13, and has the largest radius;

[0065] The left end of lens 2 abuts against the right end face of spacer A13, and the right end of spacer A13 is located in the central through hole 19;

[0066] Lens 3 is positioned between lens 2 and spacer B14;

[0067] Spacer C15 is located between lens 4 (number 4) and lens 5 (number 5).

[0068] The right end of lens 6 abuts against the right locking part 20;

[0069] A right end stop 21 is provided at the right end of the right locking part 20;

[0070] The outer wall of the lens barrel 12 is provided with threads that connect to the threaded portion of the pressure ring 11; this facilitates disassembly and assembly.

[0071] An inner step portion 16 is provided between the threaded portion of the pressure ring 11 and the inner pressure plate portion 17.

[0072] The retaining ring 11 is used to fix the entire optical system; the lens barrel 12 serves to house the lens and spacers, as well as to provide protection and support, and has threads on its outer wall for easy fixing to relevant interfaces; spacer A13 is used to ensure the air gap between L1 and L2; spacer B14 acts as an aperture stop to control the numerical aperture of the entire optical system; spacer C15 acts as a stray light stop to reduce the influence of stray light and reduce the risk of ghosting.

[0073] The lens is supported by the lens barrel 12, and detached and fixed by the pressure ring 11, which also facilitates light focusing. Spacers A13, B14, and C15 facilitate focus adjustment. The inner step 16 is raised, and the inner pressure platform 17 and the right locking part 20 limit and fix the lens. The right end stop 21 facilitates coaxial positioning and connection with other subsequent components.

[0074] Furthermore, the optical system of the wide-angle lens for equipment monitoring disclosed in this utility model also has the following features:

[0075] The focal length of the entire optical system of the wide-angle lens monitored by the equipment is set as f. The focal lengths of lens 1, lens 2, lens 3, lens 4, and the cemented lens group are represented as f1, f2, f3, f4, and f5-6, respectively. Then the focal length ranges of each lens are: 0.5 < |f1| / f < 2.5; 3 < |f2| / f < 5; 2.5 < |f3| / f < 4; 1 < |f4| / f < 3.5; and f5-6 is 4 < |f5-6| / f < 6.5.

[0076] The total optical length of the wide-angle lens used for equipment monitoring is less than or equal to 27.5mm.

[0077] The refractive index Nd of the first lens is 1.5 < Nd < 1.7, and the dispersion rate Vd is 40 < Vd < 60;

[0078] The refractive index Nd of the second lens is 1.9 < Nd < 2.1, and the dispersion rate Vd is 20 < Vd < 30;

[0079] The refractive index Nd of the third lens is 1.7 < Nd < 1.9, and the dispersion rate Vd is 25 < Vd < 35;

[0080] The refractive index Nd of the fourth lens is 1.8 < Nd < 2.0, and the dispersion rate Vd is 40 < Vd < 50;

[0081] The refractive index Nd of the fifth lens is 1.5 < Nd < 1.7, and the dispersion rate Vd is 50 < Vd < 60;

[0082] The refractive index Nd of the sixth lens is 1.8 < Nd < 2.0, and the dispersion rate Vd is 15 < Vd < 25.

[0083] The object distance of the device monitoring wide-angle lens is greater than or equal to 400 mm.

[0084] The image height of the device monitoring wide-angle lens is less than or equal to 8.1 mm.

[0085] The following is a further detailed description of the optical performance of the device monitoring wide-angle lens disclosed in the present utility model through specific embodiments.

[0086] In this embodiment, the effective focal length f of the optical lens is 3.7 mm, the aperture value FNO is 2.3, the maximum image height is 8.1 mm, the total optical length TTL = 27.2 mm, and the specific optical parameters of the optical lens are shown in Table 1:

[0087] Table 1 Optical Parameter Table

[0088]

[0089] [[ID=3​​​​​​​(1) The MTF (Modulation Transfer Function) resolution curves of this embodiment in different fields of view are as follows: Figure 3 As shown in the figure, the horizontal axis represents the spatial frequency per millimeter (lp / mm), and the vertical axis represents the MTF value. It can be seen from the figure that this embodiment exhibits good contrast within a spatial frequency range of 200 lp / mm, indicating that the overall resolution of this embodiment is high.

[0093] (2) The astigmatism curve of this embodiment is as follows: Figure 4 As shown in the figure, the horizontal axis represents focusing (mm), and the vertical axis represents the field of view. It can be seen from the figure that the astigmatism of this embodiment is relatively mild, basically controllable within 0.04mm, which to a certain extent reflects that this invention has a low level of optical distortion.

[0094] (3) The distortion F-Theta in this embodiment is as follows Figure 5 As shown in the figure, the horizontal axis represents percentage, and the vertical axis represents the field of view. It can be seen from the figure that the distortion is only -22.5% at the maximum field of view, indicating that this embodiment has low optical distortion and excellent optical performance when used as a wide-angle lens for equipment monitoring.

[0095] (4) The relative illumination curve of this embodiment is as follows: Figure 6 As shown in the figure, the horizontal axis represents the field of view angle, and the vertical axis represents the relative illuminance value. The figure shows that the system illuminance is no less than 41%, meeting the usage requirements.

[0096] (5) The optical system point diagrams of this embodiment at different fields of view are as follows: Figure 7 As shown, the image points in each field of view almost converge into an ideal point, indicating that this invention has good imaging performance.

[0097] This utility model is described in detail for the purpose of making the disclosure clearer, and the prior art will not be listed one by one.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. It is obvious to those skilled in the art that multiple technical solutions of this utility model can be combined. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model. All technical contents not described in detail in this utility model are publicly known technologies.

Claims

1. A device monitoring wide-angle lens, characterized in that: It includes an aperture (8) disposed between an object plane (7) and an image plane (9), a first group of lenses is disposed between the left side of the aperture (8) and the object plane (7); a second group of lenses is disposed between the right side of the aperture (8) and the image plane (9); The first group of lenses includes a first lens (1), a second lens (2) and a third lens (3) sequentially arranged from left to right; The second group of lenses includes a fourth lens (4) and a cemented lens group sequentially arranged from left to right; The cemented lens group includes a fifth lens (5) and a sixth lens (6) arranged in combination; The first group of lenses, the aperture (8) and the second group of lenses are coaxially arranged; The first lens (1) is a meniscus lens with a negative focal power and a convex surface facing the object plane (7); The second lens (2) is a meniscus lens with a positive focal power; The third lens (3) is a meniscus lens with a negative focal power; The fourth lens (4) is a biconvex lens with a positive focal power; The aperture (8) is disposed between the third lens (3) and the fourth lens (4); The focal length f1-3 of the first group of lenses is 1 < |f1-3| / f < 3; the focal length f4-6 of the second group of lenses is 0.5 < |f4-6| / f < 2.5; The focal length f1 of the first lens (1) is 0.5 < |f1| / f < 2.5; the focal length f2 of the second lens (2) is 3 < |f2| / f < 5; the focal length f3 of the third lens (3) is 2.5 < |f3| / f < 4; the focal length f4 of the fourth lens (4) is 1 < |f4| / f < 3.5; the focal length f5-6 of the cemented lens group is 4 < |f5-6| / f < 6.5; The optical total length TTL of the device monitoring wide-angle lens is less than or equal to 27.5 mm; the maximum outer diameter of the lens of the device monitoring wide-angle lens is less than or equal to 15 mm; The image height of the device monitoring wide-angle lens is less than or equal to 8.1 mm; The aperture number of the device monitoring wide-angle lens is less than or equal to 2.5; The first lens (1), the second lens (2), the third lens (3), the fourth lens (4), the fifth lens (5) and the sixth lens (6) are all glass spherical lenses; The refractive index Nd of the first lens (1) is 1.5 < Nd < 1.7, and the dispersion rate Vd is 40 < Vd < 60; The refractive index Nd of the second lens (2) is 1.9 < Nd < 2. ​ ​ ​ ​ ​ ​ ​ ​ A spacer A (13) is provided on the left side of spacer B (14); A pressure ring (11) is provided at the left end of the lens tube (12); An inner pressure platform (17) is provided at the left end of the pressure ring (11), and a left inner stop (18) is provided at the left end of the lens tube (12). A right locking part (20) is provided at the right end of the through hole part (19); Spacer A (13) is set in the left inner stop (18); Lens No. 1 (1) is positioned between the inner pressure stage (17) and the spacer A (13); The left end of the second lens (2) abuts against the right end face of the spacer A (13), and the right end of the spacer A (13) is located in the central through hole (19); Lens No. 3 (3) is positioned between lens No. 2 (2) and spacer B (14); Spacer C (15) is located between lens 4 (4) and lens 5 (5); The right end of lens number 6 (6) abuts against the right locking part (20); A right end stop (21) is provided at the right end of the right card slot (20); The outer wall of the lens tube (12) is provided with a thread that connects to the threaded part of the pressure ring (11); An inner step portion (16) is provided between the threaded portion of the pressure ring (11) and the inner pressure plate portion (17).

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