An infrared gun scanning counter

Abstract

This invention relates to the field of scanning counter technology and discloses an infrared gun scanning counter, comprising an optical system including, along the optical axis from the light source to the receiving surface, a point light source, a first lens, a second lens, a third lens, and a target surface, wherein: the light source is used to emit a laser point; the first lens is a glass spherical lens used to expand the laser point into an elliptical spot N times larger; the second lens is a glass spherical lens used to collimate the elliptical spot N times larger into parallel light; and the third lens is a plastic aspherical lens used to shape the collimated parallel light into a rectangular uniform spot. It can identify the quantity within a 1.5m × 0.17m range at a distance of less than 0.5m, quickly and accurately identify the number of samples within the effective target surface area, and reduce the size of the scanning counter.

Description

Technical Field

[0001] This invention relates to the field of scanning counter technology, and more particularly to an infrared gun scanning counter. Background Technology

[0002] In fields such as construction, industrial manufacturing, and warehousing and logistics, material quantity counting is a core requirement for production management and cost control. With the upgrading of industrial automation, traditional manual counting methods (low efficiency and high error rate) are gradually being replaced by automated scanning equipment. Currently, commercially available scanning counters mainly use optical imaging technology to achieve material identification and counting, with typical applications including batch inventory of regular building materials such as steel bars and pipes. The industry urgently needs high-precision, real-time, and low-cost automated counting tools, especially in dynamic and complex environments such as construction sites and factories, where equipment needs to balance deployment flexibility and anti-interference capabilities. However, existing technological solutions are limited by optical system design, making it difficult to balance the contradiction between performance, size, and cost, thus restricting their large-scale adoption.

[0003] Existing scan counters have the following key bottlenecks: limited operating distance, the device relies on long-distance projection (usually ≥2m) to ensure spot uniformity, which makes deployment difficult in confined spaces;

[0004] The system is bloated. To achieve a wide range of uniform light effects (uniformity ≥80%), multiple lens groups (4-6 lenses) and complex light sources are required. The equipment is large and heavy, making it difficult to carry and use. There is a contradiction between cost and accuracy. High-precision solutions rely on expensive optical materials (such as special glass) and precision processing technology, which increases manufacturing costs. Low-cost solutions are susceptible to interference from stray light at close range, resulting in a high counting error rate. The system lacks environmental adaptability. In complex scenarios such as dynamic stacking and uneven illumination, existing equipment is prone to missed detections or misjudgments, making it difficult to meet industrial-grade reliability requirements.

[0005] Therefore, there is an urgent need for a miniaturized, uniform, high-precision, low-cost infrared gun scanning counter capable of close-range scanning. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides an infrared gun scanning counter capable of close-range scanning.

[0007] This invention provides an infrared gun scanning counter, including an optical system.

[0008] The optical system, along the optical axis from the light source to the receiving surface, sequentially includes a point light source, a first lens, a second lens, a third lens, and a target surface, wherein:

[0009] The light source is used to emit laser dots;

[0010] The first lens is a glass spherical lens, used to expand the laser spot into an elliptical spot N times larger;

[0011] The second lens is a glass spherical lens, used to collimate an elliptical light spot that has been expanded N times into parallel light;

[0012] The third lens is a plastic aspherical lens, used to shape the collimated parallel light into a rectangular uniform light spot.

[0013] The target surface is used to receive the rectangular uniform light spot.

[0014] Furthermore, the first lens has positive optical power, the second lens has positive optical power, the third lens has negative optical power, and the optical system has positive optical power.

[0015] Furthermore, the total length L of the optical system and the back intercept L1 satisfy L≤15mm and 0 < L1 / L <0.033;

[0016] The back clipping refers to the distance from the back surface of the third lens to the projection area of ​​the light spot.

[0017] Furthermore, the refractive index range of the first lens is (1.7, 2.0).

[0018] The Abbe number range of the first lens is (25, 50);

[0019] The refractive index range of the second lens is (1.6, 1.8).

[0020] The Abbe number range of the second lens is (30, 60).

[0021] Furthermore, the aspherical surface profile of the third lens is as follows:

[0022] ;

[0023] in, , representing the curvature of the surface along the y-axis; , represents the curvature of the surface along the x-axis; z is the z-axis coordinate value; x is the x-axis coordinate value; y is the y-axis coordinate value; n is a constant; kx is the conic coefficient in the x-axis direction; ky is the conic coefficient in the y-axis direction; a1, a2, a3, a4, a5, a6, a7, a8, Ai and Bi are all coefficients.

[0024] Furthermore, the optical system has an effective focal length F=16mm, a projection distance D=500mm, and a target scanning width W=1.5m×0.15m.

[0025] Furthermore, an infrared gun scanning counter also includes:

[0026] Infrared detector: Located behind the target surface, used to receive the rectangular uniform light spot signal and convert it into an electrical signal;

[0027] Image processing unit: Performs target segmentation and quantity statistics on electrical signals using convolutional neural network algorithms;

[0028] Data output module: Transmits statistical results to the display terminal or cloud management platform in real time.

[0029] The embodiments of the present invention have the following technical effects:

[0030] 1. The three-lens collaborative design (beam expansion-collimation-shaping) is adopted. The positive optical power of the first and second lenses is used to quickly expand and collimate the beam, and the aspherical negative optical power of the third lens corrects aberrations. The field of view of the lens group is expanded to achieve "near distance wide coverage". It can identify the number of objects within a range of 1.5m×0.17m at a relatively short distance.

[0031] 2. By using a combination of two glass lenses and one plastic lens, all of which are common materials on the market, the cost is low. The first and second lenses use high-refractive-index glass to compress the optical path, and the third lens uses a low-cost plastic aspherical lens to replace multiple correction lenses. Through the aberration compensation capability of the aspherical lens, the number of lenses and air gaps are reduced, the optical system is reconstructed, the size is shortened, and the portability is significantly improved.

[0032] 3. The improved curved surface shape through the third lens separates the parameters in the x and y directions, preventing them from interfering with each other. This allows the beam to be shaped in the x and y directions. While satisfying the shaping requirements, it also ensures high uniformity of the shaped beam spot, suppresses edge light intensity attenuation, and enables rapid and accurate identification of the number of samples within the effective target area. Attached Figure Description

[0033] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0034] Figure 1 This is an optical path diagram of an optical system for an infrared gun scanning counter provided in an embodiment of the present invention;

[0035] Figure 2 This is a target surface image provided in an embodiment of the present invention;

[0036] Figure 3This is another optical path diagram of an optical system for an infrared gun scanning counter provided in an embodiment of the present invention;

[0037] Figure 4 This is a cross-sectional view of the hexagonal compound eye lens provided in an embodiment of the present invention. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0039] Figure 1 This is an optical path diagram of an optical system for an infrared gun scanning counter provided in an embodiment of the present invention. See also... Figure 1 An infrared gun scanning counter, including an optical system.

[0040] The optical system, along the optical axis from the light source to the receiving surface, sequentially includes a point light source R, a first lens G1, a second lens G2, a third lens G3, and a target surface, wherein:

[0041] The point light source R is used to emit laser points;

[0042] The first lens G1 is a glass spherical lens, used to expand the laser spot into an elliptical spot N times larger;

[0043] The second lens G2 is a glass spherical lens, used to collimate an elliptical light spot that has been expanded N times into parallel light;

[0044] The third lens G3 is a plastic aspherical lens, used to shape the collimated parallel light into a rectangular uniform light spot.

[0045] The target surface is used to receive the rectangular uniform light spot.

[0046] Specifically, when the laser beam emitted from the point source passes through the first lens, its spherical surface diffuses the beam laterally, forming an elliptical spot—a process called "beam expansion." The expanded spot size is magnified several times over to cover a wider lateral range. The second lens, also a spherical lens, re-collimates the elliptical spot into parallel light, eliminating beam divergence and ensuring consistent directionality during transmission. The third lens, made of aspherical plastic, reshapes the aligned parallel light, optimizing its surface to eliminate edge distortion and projecting a uniformly distributed rectangular spot onto the target surface. The target surface, acting as the light signal receiver, captures the spot shape and converts it into analyzable intensity distribution data.

[0047] The optical system layout of this application follows a progressive logic of "beam expansion-collimation-shaping". The beam expansion capability of the first lens determines the scanning width, the collimation effect of the second lens affects the uniformity of the light spot, and the aspherical design of the third lens is directly related to the regularity of the light spot shape. Through the cooperation of the three lenses, the system achieves wide-range, highly uniform light spot projection within a limited volume. During operation, the infrared light emitted by the light source undergoes three optical transformations to form a light field suitable for target recognition. The target surface receives the signal in real time, providing a stable input for subsequent counting. This overcomes the dependence of traditional scanning equipment on long distances, enabling large-range (1.5m × 0.17m) scanning at close range while maintaining light spot uniformity, laying the foundation for high-precision counting.

[0048] In some embodiments, the first lens G1 has positive optical power, the second lens G2 has positive optical power, the third lens G3 has negative optical power, and the optical system has positive optical power.

[0049] The optical power allocation of each lens in the optical system follows a balance principle between positive and negative optical powers. Both the first and second lenses are designed with positive optical power; the former uses positive optical power to diffuse the beam, while the latter uses positive optical power to convert the diffused beam into parallel light. The third lens is assigned negative optical power to compensate for the accumulated positive aberrations of the first two lenses and suppress distortion and stray light at the edge of the light spot. The total optical power of the overall optical system remains positive, ensuring the beam maintains convergence during transmission and avoiding energy loss. The combination of positive and negative optical power aims to achieve the dual goals of optical path controllability and aberration suppression. The series connection of the positive optical powers of the first and second lenses improves the efficiency of beam expansion and collimation, while the negative optical power of the third lens balances the system's field curvature and spherical aberration through inverse correction. During operation, the synergistic effect of optical power ensures a stable and controllable beam transmission path from the point source to the target surface, ultimately forming a rectangular light spot with clear edges and uniform energy distribution. This optical power configuration significantly improves the light spot quality while maintaining the scanning range, reducing the counting error rate.

[0050] In some embodiments, the total length L of the optical system and the back intercept L1 satisfy L≤15mm and 0 < L1 / L <0.033;

[0051] The back clipping refers to the distance from the back surface of the third lens to the projection area of ​​the light spot.

[0052] The ratio of the total length to the backstop of an optical system is a core indicator for miniaturization design. The total length refers to the axial distance from the light source to the rear surface of the third lens, while the backstop is defined as the distance from the rear surface of the third lens to the projection area of ​​the light spot on the target surface. By strictly controlling the ratio of total length (≤15mm) to backstop (L1 / L<0.033), the system achieves efficient optical path folding and energy concentration within a compact space.

[0053] In principle, the contradiction between short back intercept and long projection distance needs to be resolved by optimizing lens curvature and air gap. The aspherical design of the third lens allows it to be placed close to the target surface, thereby compressing the back intercept; at the same time, the beam-expanding capability of the first two spherical lenses is enhanced to achieve a wide scanning range with a short total length. During operation, the light path is directly projected onto the target surface after three refractions, avoiding the energy attenuation problem in traditional long optical path designs. This reduces the size of the equipment, making it suitable for space-constrained construction sites or assembly line scenarios, while ensuring the integrity of the light spot.

[0054] In some embodiments, the refractive index range of the first lens G1 is (1.7, 2.0).

[0055] The Abbe number range of the first lens is (25, 50);

[0056] The refractive index range of the second lens G2 is (1.6, 1.8).

[0057] The Abbe number range of the third lens G3 is (30, 60).

[0058] The first lens is made of high-refractive-index glass (1.7~2.0), whose high refractive properties allow for a smaller radius of curvature, thus achieving stronger beam expansion capability with a limited thickness. The second lens uses medium-refractive-index glass (1.6~1.8) combined with a high Abbe number (30~60) design, aiming to reduce the impact of dispersion on the collimation of parallel light and ensure the consistency of the transmission path of light of different wavelengths.

[0059] In some embodiments, the aspherical surface profile of the third lens G3 is as follows:

[0060] ;

[0061] in, , representing the curvature of the surface along the y-axis; , represents the curvature of the surface along the x-axis; z is the z-axis coordinate value; x is the x-axis coordinate value; y is the y-axis coordinate value; n is a constant; kx is the conic coefficient in the x-axis direction; ky is the conic coefficient in the y-axis direction; a1, a2, a3, a4, a5, a6, a7, a8, Ai and Bi are all coefficients.

[0062] The aspherical surface shape of the third lens is defined by the biconical surface equation. Its surface employs independent curvature and conic coefficients in the x and y axes, respectively, to achieve differentiated beam control. The high curvature in the x-axis direction is used to compress the beam width, forming the short side of the rectangular spot; the low curvature in the y-axis direction maintains the beam length, shaping the long side of the spot. The introduction of polynomial coefficients (such as a1~a8, Ai, Bi) further corrects local surface details and eliminates residual aberrations.

[0063] Optionally, since the aspherical surface shape of the third lens needs to satisfy the beam shaping in the x and y directions, the parameters in the x and y directions in the expression must be separate and independent. In addition to satisfying the shaping condition, high uniformity of the shaped beam spot is also required, necessitating additional parameters for beam homogenization. Furthermore, while meeting these requirements, the lens must also be easy to manufacture and process. The aspherical surface shape of the third lens can also be selected from the following two options:

[0064] 1. Cylindrical Fresnel lens:

[0065] ;

[0066] Where z is the z-axis coordinate value; x is the x-axis coordinate value; y is the y-axis coordinate value; n is a constant; a1, a2, a3, a4, a5, a6, a7, a8, Ai and Bi are all coefficients; c=1 / r, and k represents the conic coefficient.

[0067] The characteristics of this expression are: the x-direction is an infinitely large plane, and the y-direction can have different curvatures and radii, thus satisfying the initial shaping requirements in the x and y directions. However, if the uniformity of the light spot edge and center is very high, this equation cannot satisfy the requirements.

[0068] 2. Biconical Zernike equations:

[0069] ;

[0070] in, , representing the curvature of the surface along the y-axis; , represents the curvature of the surface along the x-axis; z is the z-axis coordinate; x is the x-axis coordinate; y is the y-axis coordinate; n is a constant; k x k is the conic coefficient in the x-axis direction. y α is the conic coefficient in the y-axis direction; i β i All are coefficients; y i The value represents the axis; P represents the normalized radial coordinate. This represents the normalized radial angle, and N represents the number of terms.

[0071] This equation is an improvement on the above equation. It has curvature in both the x and y directions, and the curvature in the two directions does not interfere with each other. It can further satisfy the shaping in the x and y directions based on the above expression. At the same time, since this equation has polynomials in both the x and y directions, it can further homogenize the light spot in the x and y directions to obtain a very uniform light spot that meets the requirements.

[0072] In some embodiments, the optical system has an effective focal length F=16mm, a projection distance D=500mm, and a target scanning width W=1.5m×0.15m.

[0073] The effective focal length of the optical system is set at 16mm, a value that balances the requirements of short-distance projection and wide-area coverage. At short projection distances, the short focal length design expands the field of view, allowing the target surface to receive a scanning area of ​​1.5m × 0.17m. In the optical path design, the matching of focal length and projection distance is achieved through the optical power distribution of the lens group: the first two positive optical power lenses expand the field of view, and the third lens with negative optical power corrects the curvature of the image plane, ultimately forming a distortion-free wide spot on the target surface.

[0074] In some embodiments, the collimated parallel light can also be shaped into various shapes of light spots, such as square light spots, pentagonal light spots, hexagonal light spots, etc.

[0075] If the light spot is shaped into a square, the aspherical surface of the third lens is an even-order aspherical surface, and the specific surface shape formula is:

[0076] ;

[0077] Where r is the perpendicular distance from a point on the surface to the optical axis; c represents the reciprocal of the radius of curvature (i.e., curvature), defined as 1 / R, where R is the radius of curvature at the vertex of the surface; k is the conic constant, which determines the basic type of the surface; α1, α2, α3, α4, α5, α6, α7, and α8 are coefficients of higher-order terms, which are used to adjust and optimize the aspherical properties of the lens to reduce aberration problems.

[0078] If the light spot is shaped into a pentagon, hexagon, or other special shape, a compound eye lens with a special shape is added after the third lens G3. Its function is to further collimate the parallel light into the required shape.

[0079] For example, if the shape is hexagonal, and a hexagonal compound eye lens G4 is added after the third lens G3, the optical path diagram of the optical system is as follows. Figure 3 As shown. The function of the hexagonal compound eye lens G4 is to further transform the shaped special light rays into the desired hexagonal light spot. The specific cross-section of the hexagonal compound eye lens G4 is shown in the figure. Figure 4 As shown.

[0080] Furthermore, an infrared gun scanning counter also includes:

[0081] Infrared detector: Located behind the target surface, used to receive the rectangular uniform light spot signal and convert it into an electrical signal;

[0082] Image processing unit: Performs target segmentation and quantity statistics on electrical signals using convolutional neural network algorithms;

[0083] Data output module: Transmits statistical results to the display terminal or cloud management platform in real time.

[0084] It should be noted that the terminology used in this invention is for describing specific embodiments only and is not intended to limit the scope of this application. As shown in this specification, unless the context clearly indicates otherwise, words such as "a," "an," "an," and / or "the" do not specifically refer to the singular and may include the plural. The terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, or apparatus that includes said element.

[0085] It should also be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present 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 the present invention. Unless otherwise expressly specified and limited, the terms "installed," "connected," "linked," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components. For those skilled in the art, the specific meaning of the above terms in the present invention can be understood according to the specific circumstances.

[0086] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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 or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the technical solutions of the embodiments of the present invention.

Claims

1. An infrared gun scanning counter, characterized by Including optical systems, The optical system, along the optical axis from the light source to the receiving surface, sequentially includes a point light source, a first lens, a second lens, a third lens, and a target surface, wherein: The point light source is used to emit laser points; The first lens is a glass spherical lens, used to expand the laser spot into an elliptical spot N times larger; The second lens is a glass spherical lens, used to collimate an elliptical light spot with a beam multiple of N into parallel light; The third lens is a plastic aspherical lens, used to shape the collimated parallel light into a rectangular uniform light spot. The target surface is used to receive the rectangular uniform light spot.

2. The infrared gun scanning counter according to claim 1, characterized in that, The first lens has positive optical power, the second lens has positive optical power, the third lens has negative optical power, and the optical system has positive optical power.

3. The infrared gun scanning counter according to claim 1, characterized in that, The total length L of the optical system and the back intercept L1 satisfy L≤15mm and 0 < L1 / L <0.033; The back clipping refers to the distance from the back surface of the third lens to the projection area of ​​the light spot.

4. An infrared gun scanning counter according to claim 1, characterized in that, The refractive index range of the first lens is (1.7, 2.0). The Abbe number range of the first lens is (25, 50); The refractive index range of the second lens is (1.6, 1.8). The Abbe number range of the second lens is (30, 60).

5. An infrared gun scanning counter according to claim 1, characterized in that, The aspherical surface profile of the third lens is as follows: ； wherein, represents the curvature of the curved surface in the y-axis direction; represents the curvature of the curved surface in the x-axis direction; z is a z-axis coordinate value; x is an x-axis coordinate value; y is a y-axis coordinate value; and n is a constant; k x is a conic coefficient in the x-axis direction; k y is a conic coefficient in the y-axis direction; a1, a2, a3, a4, a5, a6, a7, a8, A i and B i are coefficients.

6. An infrared gun scanning counter according to claim 1, characterized in that, The optical system has an effective focal length F=16mm, a projection distance D=500mm, and a target scanning width W=1.5m×0.15m.

7. An infrared gun scanning counter according to claim 1, characterized in that, Also includes: Infrared detector: Located behind the target surface, used to receive the rectangular uniform light spot signal and convert it into an electrical signal; Image processing unit: Performs target segmentation and quantity statistics on electrical signals using convolutional neural network algorithms; Data output module: Transmits statistical results to the display terminal or cloud management platform in real time.

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