Low-cost laser ranging receiving lens

Abstract

The utility model relates to a low-cost laser ranging receiving lens, and belongs to the technical field of laser lenses, and the low-cost laser ranging receiving lens comprises diaphragm gears which are sequentially arranged from an object side surface to an image side surface; the lens is located on the rear side of the diaphragm gear, and the lens is a plano-convex lens with positive focal power; and the light filtering part is integrally connected to the object side surface of the lens. According to the invention, one lens is simple to process, install and adjust, the detection precision is higher, the cost of one lens is also low, and batch low-cost production is easy to realize.

Description

Technical Field

[0001] This application relates to the technical field of laser lenses, and particularly to a low-cost laser ranging receiving lens. Background Art

[0002] With the development of laser technology, laser ranging has been gradually used in various fields such as production, life, and military industry. It has been widely used due to its advantages of high precision, fast response, and simple operation. The laser ranging receiving lens is an important component among them.

[0003] Conventional laser receiving lenses generally consist of two or more single lenses and a narrowband filter. The number of optical components is relatively large, and the corresponding cost is also relatively high.

[0004] With the development of modern products towards high quality, high precision, and low cost, conventional laser receiving lenses gradually lack market competitiveness and are difficult to meet the modern requirements of high quality, high precision, and low cost. Summary of the Invention

[0005] The embodiments of this application provide a low-cost laser ranging receiving lens to solve the problem that in related technologies, conventional laser receiving lenses are difficult to meet the modern requirements of high quality, high precision, and low cost.

[0006] The embodiments of this application provide a low-cost laser ranging receiving lens, including a diaphragm stop arranged in sequence from the object side to the image side; a lens located at the rear side of the diaphragm stop, the lens being set as a plano-convex lens with a positive focal power; and a filter element integrally connected to the object side of the lens.

[0007] By adopting the above technical solution, the lens, the filter element, and the diaphragm stop are provided. The light quantity is input from the object side towards the lens, and the light input quantity is restricted by the diaphragm stop. At the same time, the filter element is arranged on the object side of the front surface of the lens, which can make the incident angle of the filter element smaller, resulting in a lower signal-to-noise ratio of the laser ranging receiving lens and a better ranging effect. Therefore, the integrated setting of the lens and the filter element meets the usage requirements, has a low cost, and is easy to achieve mass production at low cost.

[0008] In some embodiments, the object side of the lens is a plane, and the image side is a convex surface.

[0009] By adopting the above technical solution, the lens has a flat object side and a convex image side. The flat object side is used for plating the filter element to achieve a small-angle incidence of the filter film, and the convex image side is used for converging the laser beam.

[0010] In some embodiments, the lens material is a low-melting-point molding material.

[0011] By adopting the above technical solutions, the low-melting-point molding material has characteristics such as low melting point, easy to process and mix, and capable of rapid melting and solidification, so that it can directly mold the lens and is easy to achieve mass production at low cost.

[0012] In some embodiments, the convex surface of the lens is an aspherical surface type.

[0013] By adopting the above technical solutions, using an aspherical surface type for the convex surface can better correct aberration and make the laser reception effect better.

[0014] In some embodiments, the filter element includes a narrow-band filter film, and the narrow-band filter film is deposited on the flat surface of the lens.

[0015] By adopting the above technical solutions, the narrow-band filter film is directly integrally deposited on the lens, so that the use requirement can be met even with a single lens. Depositing the filter film on the flat surface can make the incident angle of the filter film smaller, realizing selective transmission of the laser band. When the laser narrow band is narrower, the signal-to-noise ratio of the laser ranging receiving lens is lower, the detection error is reduced, and the ranging effect is better.

[0016] In some embodiments, a laser antireflection film is deposited on the convex surface of the lens.

[0017] By adopting the above technical solutions, depositing a laser antireflection film on the convex surface to achieve high-efficiency antireflection of the laser can reduce the reflection loss of light on the lens surface, thereby increasing the light transmission amount, making the lens clearer and brighter, and improving the detection accuracy.

[0018] In some embodiments, the Abbe number of the lens is between 20 and 90.

[0019] By adopting the above technical solutions, the Abbe number of the lens is used to describe the dispersion performance of the lens. When the Abbe number is between 20 and 90, a large selection range is provided, and a suitable lens can be selected according to specific application requirements and cost budgets to provide better dispersion performance, thereby reducing chromatic aberration and improving imaging quality.

[0020] In some embodiments, the divergence angle of the received laser beam of the lens is not greater than 2 mrad.

[0021] By adopting the above technical solutions, when the divergence angle of the received laser beam of the lens is not greater than 2 mrad, the lens has a relatively small beam divergence degree when receiving the laser beam. A smaller divergence angle means that the laser beam can maintain better stability during propagation, is not prone to obvious diffusion, and the measurement error caused by beam divergence can be controlled at a lower level, thereby improving the measurement accuracy.

[0022] In some embodiments, the applicable wavelength band of the lens is 1535 nm.

[0023] By adopting the above technical solution, the applicable wavelength band of the lens is 1535 nm, and it has good optical performance in the near-infrared wavelength band near this specific wavelength. Therefore, this lens can better adapt to the laser emitter in the 1535 nm wavelength band.

[0024] In some embodiments, the lens is made of low-melting-point glass.

[0025] By adopting the above technical solution, the low-melting-point glass material for molding can be directly molded, without the cumbersome process route of traditional lenses, which saves more costs.

[0026] The beneficial effects brought by the technical solution provided in this application include:

[0027] The embodiment of this application provides a low-cost laser ranging receiving lens. Since the filter element and the lens are integrally connected in this application, the laser ranging receiving lens is composed of only one lens, which can meet the use requirements of laser ranging. After the light source is input from the object side of the lens, the amount of incident light is restricted by the diaphragm gear. Then, the light passes through the filter element arranged on the object side of the lens to realize the selective transmission of the laser wavelength band, making the incident angle of the filter element smaller and the laser narrow band narrower, resulting in a lower signal-to-noise ratio of the laser ranging receiving lens and a better ranging effect. For the detection of a light source with a small angle in general, the conventional related technology requires two or more single lenses and a narrow-band filter, and the large number of optical components will lead to a large error in the laser ranging receiving lens. After the filter element and the lens are integrally connected in this application, there is only one optical component, and the processing and alignment are simple, which can reduce the cumulative error. Therefore, the detection accuracy of one lens is higher, and the cost of one lens is also low, which is easy to achieve mass production at low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of this application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of this application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 It is the overall structure diagram provided by the embodiment of this application;

[0030] Figure 2 It is the structure diagram showing the state of the lens receiving the light source provided by the embodiment of this application.

[0031] Reference Numerals:

[0032] 1, lens; 2, diaphragm gear; 3, object side; 4, image side. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0034] The embodiments of the present application provide a low-cost laser ranging receiving lens, which can solve the problem that conventional laser receiving lenses are difficult to meet the requirements of modern high quality, high precision, and low cost.

[0035] See Figure 1 and Figure 2 As shown, the embodiments of the present application provide a low-cost laser ranging receiving lens, including a diaphragm stop 2, a lens 1, and a filter element sequentially arranged from the object side 3 to the image side 4. The lens 1 is set as a plano-convex lens with a positive optical power, and the thickness of the lens 1 is preferably set to 8 mm; the filter element is integrally connected to the lens 1 and is connected to the object side 3 of the lens 1, and the diaphragm stop 2 is arranged on the front surface of the lens 1.

[0036] During the use of laser ranging, light is input from the object side 3 towards the lens 1, and the amount of incident light is restricted by the diaphragm stop 2 to ensure that an appropriate amount of light source passes through the lens 1 for detection; the filter element is integrally connected to the lens 1, so that the angle of incidence on the filter element is smaller and the laser narrowband is narrower, which can better achieve the selective transmission of the laser band and make the laser ranging effect better. At this time, only one lens 1 is provided to meet the use requirements. Compared with the conventional technical means of using two or more single lenses and a narrowband filter to form a lens for receiving small-angle light beams, the increase in the number of lenses of the laser ranging receiving lens will lead to a large error in the laser ranging receiving lens; while in the present application, the filter element is integrally connected to the lens 1, the number of optical components is reduced, which can reduce the detection error. The detection accuracy of the single lens 1 is high, the cost is low, and it is easy to achieve mass production at low cost.

[0037] In the present application, the object side 3 of the lens 1 is a plane, and the image side 4 is a convex surface. The convex design of the image side 4 can more effectively collect and focus light, reduce light loss, and compared with a biconvex lens, the manufacturing process of the plano-convex lens may be simpler because only a convex surface needs to be processed on one surface, which reduces the manufacturing cost and improves the production efficiency.

[0038] In this application, the material of lens 1 is preferably a low-melting-point molding material, and is preferably set as low-melting-point glass. The low-melting-point molding material refers to a material with a relatively low melting point, whose melting point is below 200 degrees Celsius, and has characteristics such as low melting point, easy to process and mix, and can quickly melt and solidify. The low-melting-point glass can be directly molded, without the cumbersome process route of traditional lenses, which is more cost-saving.

[0039] In this application, the convex surface of lens 1 is an aspherical surface type, and the conic coefficient of lens 1 is preferably -2.466, and the radius of curvature is preferably -27.40 mm; the aspherical surface type lens 1 can focus according to the position and angle of light incidence, thereby improving the clarity and resolution of imaging. Compared with the spherical lens 1, the aspherical surface type lens 1 can reduce the marginal aberration, making the image edge clearer and the details richer; in addition, the aspherical lens 1 can achieve higher focusing accuracy, focus the light on a smaller spot, and achieve more efficient and accurate operation.

[0040] In this application, the filter element includes a narrow-band filter film, and the narrow-band filter film is deposited on the plane of lens 1. Depositing the filter film on the plane can make the incident angle of the filter film smaller, allowing light of a specific wavelength band to pass through while blocking light of other wavelength bands, thereby reducing the interference of stray light on the imaging quality; therefore, this characteristic enables lens 1 to accurately locate and transmit the required wavelength, improving the accuracy and clarity of imaging. And when the laser narrow band is narrower, the signal-to-noise ratio of the laser ranging receiving lens is lower, and the ranging effect is better.

[0041] Furthermore, a laser antireflection film is deposited on the convex surface of lens 1. The laser antireflection film can significantly improve the transmittance of lens 1, making the lens clearer and brighter. This is because the laser antireflection film can reduce the reflection loss of light on the lens surface, thereby increasing the amount of light transmission; in addition, the laser antireflection film can effectively prevent light reflection, reduce light interference, make the object more real, and obtain a clearer and more real visual experience.

[0042] In this application, the Abbe number of the lens 1 is a key parameter in optical design. It is mainly used to describe the dispersion performance of lens 1. The higher the Abbe number, the better the dispersion performance of lens 1, that is, it can better eliminate chromatic aberration. Setting the Abbe number of the lens 1 between 20 and 90 provides a large selection range, and the appropriate lens 1 can be selected according to specific application requirements and cost budgets.

[0043] In this application, the divergence angle of the received laser beam of lens 1 is no more than 2 mrad. When lens 1 receives the laser beam, it has a relatively small degree of beam divergence, which brings the following benefits in practical applications: A smaller divergence angle means that the laser beam can maintain good stability during propagation and is not prone to obvious diffusion. This is crucial for applications that require precise control and transmission of laser beams; A smaller divergence angle also means that the laser beam has a higher energy concentration. In fields such as laser processing, measurement, and communication, a laser beam with a high energy concentration can improve work efficiency, reduce energy loss, and enhance system performance; In applications such as lidar and wind speed measurement, the size of the divergence angle of the received optical path beam directly affects the measurement accuracy. When the divergence angle of the received laser beam is no more than 2 mrad, the measurement error caused by beam divergence can be controlled at a low level, thereby improving the measurement accuracy.

[0044] In this application, the applicable wavelength band of lens 1 is 1535 nm. This generally means that lens 1 has good optical properties in the near-infrared wavelength band near 1535 nm, including but not limited to high transmittance, low dispersion, and low absorption.

[0045] In this application, the distance of the curved surface of lens 1 from the vertex of the curved surface in the optical axis direction is specifically calculated using the following formula:

[0046]

[0047] Where Z represents the distance of the curved surface from the vertex of the curved surface in the optical axis direction, c represents the curvature of the vertex of the curved surface, preferably set to 1 / -27.4; k represents the conic coefficient, preferably set to -2.466; r represents the distance from the optical axis to the curved surface; A, B, C, and D respectively represent the second-order, fourth-order, sixth-order, and eighth-order curved surface coefficients, and A, B, C, and D are respectively preferably set to 0, 2.6623E-009, -3.1920E-012, and 0.

[0048] The principle of the embodiment of this application is as follows: Conventional laser receiving lenses generally consist of two or more single lenses and a narrow-band filter. The number of optical components is relatively large, and the corresponding cost is also relatively high. With the development of modern products towards high quality, high precision, and low cost, conventional laser receiving lenses gradually lack market competitiveness and are difficult to meet the requirements of modern high quality, high precision, and low cost. Therefore, this application uses a lens 1 with a flat object side 3 and a convex image side 4. A narrow-band filter film and a laser antireflection film are integrally coated on lens 1 to achieve selective transmission and convergence of the laser beam. Compared with the conventional laser receiving lens composed of two or more single lenses and a narrow-band filter, the number of optical components used in this application is small, the detection error is small, and the material of lens 1 is a low-melting-point molding material, which can be directly molded aspherically, making it easy to achieve mass production at low cost.

[0049] In the description of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "upper" and "lower" is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present application. Unless otherwise clearly specified and defined, the terms "installed", "connected" and "connected" 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 directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0050] It should be noted that in the present application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising one..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the said element.

[0051] The above are only specific embodiments of the present application, enabling those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A low-cost laser ranging receiving lens, characterized in that, Including a diaphragm stop (2) arranged in sequence from the object side (3) to the image side (4); A lens (1), which is located at the rear side of the diaphragm stop (2), and the lens (1) is set as a plano-convex lens with positive optical power; A filter element, which is integrally connected to the object side (3) of the lens (1). The object side (3) of the lens (1) is a plane, and the image side (4) is a convex surface.

2. The low-cost laser ranging receiving lens according to claim 1, wherein: The material of the lens (1) is a low-melting-point molding material.

3. The low-cost laser ranging receiving lens according to claim 1, characterized in that: The convex surface of the lens (1) is an aspherical surface type.

4. The low-cost laser ranging receiving lens according to claim 1, characterized in that: The filter element includes a narrow-band filter film, and the narrow-band filter film is plated on the plane of the lens (1).

5. The low-cost laser ranging receiving lens according to claim 1, wherein: A laser anti-reflection film is plated on the convex surface of the lens (1).

6. The low-cost laser ranging receiving lens according to claim 5, characterized in that: The Abbe number of the lens (1) is between 20 and 90.

7. The low-cost laser ranging receiving lens according to claim 1, characterized in that: The divergence angle of the received laser beam of the lens (1) is not greater than 2 mrad.

8. The low-cost laser ranging receiving lens according to claim 7, characterized in that: The applicable wavelength band of the lens (1) is 1535 nm.

9. The low-cost laser ranging receiving lens according to claim 7, wherein: The lens (1) is made of a low-melting-point glass.

10. A low-cost laser ranging receiving lens according to claim 3, characterized in that: ​

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