Extremely simple laser fuze emission beam expanding optical lens

Abstract

The invention provides a laser fuze emission beam-expanding optical lens in an extremely simple form, and the optical lens comprises an emission lens which is located at the rear end of the lens and is used for carrying out the small-angle compression shaping of a beam divergence angle of a meridian-direction Gaussian beam emitted by a laser; and the wave mirror is positioned at the front end of the lens and is used for carrying out large-angle beam expansion on the beam divergence angle of the Gaussian beam emitted by the laser in the sagittal direction and realizing uniform shaping of light spots. Strip-shaped distribution shaping is carried out on Gaussian beams of the laser through the extremely simple form of the two lenses, so that the light beam emergent view field in one direction, namely the meridian direction, is compressed to 1 degree, and the light beam emergent view field in the other vertical direction, namely the sagittal direction, is expanded to 90 degrees. By adopting the special element design of the cylindrical surface array, the uniform energy distribution of the whole strip-shaped light spot is realized, the target detection precision of the surface-air laser fuze in a large-range space region is greatly improved, and meanwhile, the extremely simple design is more beneficial to meeting the requirements of miniaturization and low cost.

Description

Technical Field

[0001] This application relates to the field of optical equipment technology, specifically to a simplified laser fuze beam-expanding optical lens. Background Technology

[0002] The primary function of a laser fuze is to detect a target using a laser, calculate and process the laser echo information to determine the target's location, and then send a signal at an appropriate position and time to lock onto the target, maximizing its destructive capability at close range. The main function of the laser fuze's emitting lens is to shape and radiate the laser beam into space according to requirements, creating the necessary detection field. However, existing laser fuzes have complex optical lens structures, high costs, and are inconvenient to install; therefore, these problems urgently need to be addressed. Summary of the Invention

[0003] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a simplified laser fuze beam expander optical lens.

[0004] This application provides a simplified laser fuze beam-expanding optical lens, including... The emitting lens, located at the rear end of the lens, is used to compress and shape the beam divergence angle of the meridional Gaussian beam emitted by the laser at a small angle. A wave mirror, located at the front end of the lens, is used to expand the beam divergence angle of the Gaussian beam emitted by the laser at a large angle and to achieve uniform shaping of the beam spot.

[0005] Furthermore, The working wavelength of the lens is 880nm~930nm; The numerical aperture of the lens is not less than 0.3.

[0006] Furthermore, The emitting lens is made of ZnSe and has a thickness ranging from 1.5mm to 2mm. The radius of the front surface of the transmitting lens ranges from 8mm to 10mm, and the radius of the rear surface ranges from 15mm to 20mm.

[0007] Furthermore, The front surface of the transmitting lens is aspherical, with an aspherical coefficient of A = -3.497373 × 10⁻⁶. -5 B = -4.009105 × 10 -7 C = -3.609262 × 10 -9 D = -7.575323 × 10 -11 .

[0008] Furthermore, The aperture range of the front surface of the transmitting lens is φ6mm to φ8mm, and the aperture range of the rear surface is φ6mm to φ8mm.

[0009] Furthermore, The wave mirror is made of optical plastic, with a flat front surface and a periodically arranged cylindrical structure on the rear surface, forming a wave-shaped structure.

[0010] Furthermore, The radius of the cylindrical surface ranges from 0.1 mm to 0.3 mm.

[0011] Furthermore, The thickness of the wave mirror is 1mm to 1.5mm; The light-transmitting aperture range of the front surface of the wave mirror is φ8mm~φ10mm, and the light-transmitting aperture range of the rear surface is φ8mm~φ10mm.

[0012] Furthermore, The distance between the transmitting lens and the wave mirror varies from 1mm to 3mm.

[0013] Furthermore, The distance between the emitting lens and the laser assembly varies from 8mm to 10mm.

[0014] The advantages and positive effects of this application are: This technical solution achieves the fine strip distribution shaping of the Gaussian beam of a semiconductor laser through a minimalist form using two lenses. This compresses the beam's field of view to 1° in one direction, namely the meridional direction, while expanding it to 90° in the other perpendicular direction, namely the sagittal direction. Furthermore, the use of a special cylindrical array element design achieves uniform energy distribution across the entire fine strip spot, greatly improving the target detection accuracy of the surface-mount laser fuze over a wide spatial area. At the same time, the minimalist design is more conducive to meeting the requirements of miniaturization and low cost. Attached Figure Description

[0015] Figure 1 A simplified structural diagram of a laser fuze beam-expanding optical lens provided in this application embodiment; Figure 2 A schematic diagram of the light spot illuminance distribution of a simplified laser fuze beam expander optical lens provided in this application embodiment; Figure 3 A schematic diagram of the illuminance distribution curve of the sagittal direction light spot of the simplified laser fuze beam expander optical lens provided in the embodiments of this application; Figure 4This is a schematic diagram of the meridional illuminance distribution curve of a simplified laser fuze beam expander lens provided in an embodiment of this application.

[0016] The text labels in the figure are: 100 - emission lens; 200 - wave mirror. Detailed Implementation

[0017] To enable those skilled in the art to better understand the technical solution of this application, the application will be described in detail below with reference to the accompanying drawings. The description in this section is only exemplary and explanatory, and should not be used to limit the scope of protection of this application.

[0018] Please refer to Figure 1 This embodiment provides a simplified laser fuze beam-expanding optical lens, including an emitting lens 100 located at the rear end of the lens, used to compress and shape the beam divergence angle of the meridional Gaussian beam emitted by the laser at a small angle; and a wave mirror 200 located at the front end of the lens, used to expand the beam divergence angle of the sagittal Gaussian beam emitted by the laser at a large angle, and to achieve beam spot uniformity shaping.

[0019] In this embodiment, the emitting lens 100 is located behind the wave mirror 200 and relatively close to the laser. The two-piece minimalist structure of the emitting lens 100 and the wave mirror 200 replaces the complex multi-lens design of traditional laser fuze lenses. While achieving the core function, it significantly reduces the size, weight and manufacturing cost of the lens, making it easy to install and integrate into miniaturized fuze devices. Specifically, the small-angle compression of the Gaussian beam in the meridional direction by the transmitting lens 100 and the large-angle beam expansion in the sagittal direction by the wave mirror 200 work together to accurately realize the spatial distribution of the fine strip-shaped light spot. This ensures the detection accuracy in the meridional direction, i.e., a narrow field of view of 1°, while covering a large area of ​​space through a large field of view of 90° in the sagittal direction, thus greatly improving the breadth and accuracy of target detection.

[0020] In this embodiment, the laser parameters are: Laser wavelength range: λ = 895 nm to 915 nm; Laser beam angle (half-power point): θ∥=12°, θ⊥=25°; Laser emitting surface dimensions: 240μm × 390μm.

[0021] In a preferred embodiment, the operating wavelength of the lens is 880nm to 930nm; the numerical aperture of the lens is not less than 0.3.

[0022] In this embodiment, the operating wavelength is matched to the commonly used output wavelength of semiconductor lasers, namely 895nm to 915nm, which reduces the absorption loss of laser in the lens and improves optical efficiency.

[0023] In this embodiment, the numerical aperture is not less than 0.3, which ensures that the lens can efficiently collect the Gaussian beam emitted by the laser, enhancing the ability to utilize weak light signals. Especially when detecting at long distances, it can improve the intensity and stability of the echo signal.

[0024] In a preferred embodiment, the emitting lens 100 is made of ZnSe and has a thickness of 1.6 mm; the radius of the front surface of the emitting lens 100 is 9 mm, and the radius of the rear surface is 18.5 mm.

[0025] In this embodiment, the emitting lens 100 is made of zinc selenide, which has a transmittance of over 90% in the 880nm-930nm wavelength band, significantly reducing laser energy loss; at the same time, zinc selenide has good mechanical strength and environmental resistance, making it suitable for long-term stable operation under complex working conditions.

[0026] In a preferred embodiment, the front surface of the emitting lens 100 is aspherical, and the aspheric coefficient is A = -3.497373 × 10⁻⁶. -5 B = -4.009105 × 10 -7 C = -3.609262 × 10 -9 D = -7.575323 × 10 -11 .

[0027] In this embodiment, the front surface adopts an aspherical design, which can effectively correct aberrations such as spherical aberration and coma compared with traditional spherical lenses, making the beam compression in the meridional direction more uniform, improving the focusing accuracy of the edge beam by more than 30%, avoiding the problem of excessive energy attenuation at the edge of the light spot, and ensuring the detection consistency within a 1° field of view in the meridional direction.

[0028] In a preferred embodiment, the aperture of the front surface of the emitting lens 100 is φ7.5mm, and the aperture of the rear surface is φ8mm.

[0029] In this embodiment, the aperture of the front and rear surfaces is matched with the size of the laser beam emitted from the laser. This allows for the complete reception of the main lobe energy of the Gaussian beam without causing stray light interference due to excessive aperture size. At the same time, the compact size of φ6mm to φ8mm further supports the miniaturization design of the lens and is compatible with the limited installation space of the fuze device.

[0030] In a preferred embodiment, the wave mirror 200 is made of optical plastic, with a flat front surface and a periodically arranged cylindrical structure on the rear surface, forming a wave-shaped structure.

[0031] In this embodiment, optical plastic material is used, which reduces the weight by more than 50% compared to materials such as glass. The injection molding process is suitable for mass production, which greatly reduces manufacturing costs. At the same time, the light transmittance of optical plastic in the working wavelength range can meet the usage requirements, taking into account both economy and functionality.

[0032] In this embodiment, the periodic cylindrical structure on the rear surface, i.e. the wave shape, is the core design for achieving large-angle beam expansion (up to 90°) in the sagittal direction and uniformity of the beam spot: the periodic distribution of the cylindrical surface can disperse and redistribute the energy of the Gaussian beam, thereby improving the uniformity of the beam spot energy to more than 90%, avoiding the detection blind zone or misjudgment caused by the excessive strength at the center and the excessive weakness at the edge of the traditional Gaussian beam spot.

[0033] In a preferred embodiment, the radius of the cylinder is 0.2 mm.

[0034] In this embodiment, this parameter ensures that the beam expansion angle in the sagittal direction is precisely controlled at 90°, while the curvature of the cylinder matches the divergence characteristics of the Gaussian beam, further improving the uniformity of the beam spot.

[0035] In a preferred embodiment, the thickness of the wave mirror 200 is 1.1 mm; the light transmission aperture range of the front surface of the wave mirror 200 is φ8.5 mm, and the light transmission aperture range of the rear surface is φ9 mm.

[0036] In this embodiment, the 1.1mm thickness reduces the amount of optical plastic material used and the transmission loss of the light beam in the lens while ensuring structural strength, and also reduces the overall thickness of the lens.

[0037] In this embodiment, the φ8.5mm aperture is larger than the emitting lens 100, which can fully receive the light beam after it has been shaped by the emitting lens 100, avoid the edge beam being blocked, ensure a complete field of view of 90°×1°, and at the same time form a reasonable match with the aperture of the emitting lens 100 to reduce stray light entering.

[0038] In a preferred embodiment, the distance between the emitting lens 100 and the wave mirror 200 is 1.5 mm.

[0039] In this embodiment, the distance range is crucial for the synergistic optical performance of the two lenses; too close and the beam will not be fully shaped before entering the next lens, while too far and the beam will diverge, resulting in energy loss; the 1.5mm distance ensures that the beam compressed in the meridional direction and the beam expanded in the sagittal direction are precisely superimposed in space, forming a 90°×1° thin strip of light with clear edges and uniform energy, thus improving the stability of the detection field.

[0040] In a preferred embodiment, the distance between the emitting lens 100 and the laser assembly is 9 mm.

[0041] In this embodiment, the distance matches the characteristics of the emitted laser beam, allowing the Gaussian beam to be incident on the emitting lens 100 at the optimal angle, ensuring the beam divergence angle compression effect in the meridional direction (to 1°); at the same time, it avoids beam oversaturation caused by too close a distance or energy attenuation caused by too far a distance, improves the utilization rate of the laser output energy by the lens, and ensures the strength of the detection signal.

[0042] Please refer to further information. Figures 2-4 The image shows the beam energy distribution of a simplified laser fuze beam expander lens, created using LightTools optical simulation software. Figure 2 This describes the distribution of light spot energy and illuminance at the effective distance of the lens. Figures 3-4 The figures show the energy illuminance distribution curves of the lens in the sagittal and meridional directions at the effective distance. In the simulation software, the light source is set as an elliptical Gaussian beam, and the effective distance is set at 20m from the lens. The horizontal axis represents the spot size, and the vertical axis represents the spot energy illuminance value. Based on the spot size distribution, the laser emission field of view after shaping can be calculated to be 90°×1°. Based on the spot energy illuminance value, it can be seen that the spot uniformity effect is better.

[0043] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of textual expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this invention, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A simplified laser fuze beam expander optical lens, characterized in that, include The emitting lens (100) is located at the rear end of the lens and is used to compress and shape the beam divergence angle of the meridional Gaussian beam emitted by the laser at a small angle. A wave mirror (200) is located at the front end of the lens and is used to expand the beam divergence angle of the Gaussian beam emitted by the laser at a large angle and to achieve uniform shaping of the beam spot.

2. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The working wavelength of the lens is 880nm~930nm; The numerical aperture of the lens is not less than 0.

3.

3. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The emitting lens (100) is made of ZnSe and has a thickness ranging from 1.5 mm to 2 mm. The radius of the front surface of the emitting lens (100) ranges from 8 mm to 10 mm, and the radius of the rear surface ranges from 15 mm to 20 mm.

4. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The front surface of the emitting lens (100) is aspherical, and the aspherical coefficient is A = -3.497373 × 10⁻⁶. -5 B = -4.009105 × 10 -7 C = -3.609262 × 10 -9 D = -7.575323 × 10 -11 .

5. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The aperture range of the front surface of the emitting lens (100) is φ6mm to φ8mm, and the aperture range of the rear surface is φ6mm to φ8mm.

6. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The wave mirror (200) is made of optical plastic, with a flat front surface and a periodically arranged cylindrical structure on the rear surface, forming a wave-shaped structure.

7. The simplified laser fuze beam-expanding optical lens according to claim 6, characterized in that, The radius of the cylindrical surface ranges from 0.1 mm to 0.3 mm.

8. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The thickness of the wave mirror (200) is 1mm to 1.5mm; The light-transmitting aperture range of the front surface of the wave mirror (200) is φ8mm~φ10mm, and the light-transmitting aperture range of the rear surface is φ8mm~φ10mm.

9. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The distance between the emitting lens (100) and the wave mirror (200) varies from 1 mm to 3 mm.

10. The simplified laser fuze beam-expanding optical lens according to claim 1, characterized in that, The distance between the emitting lens (100) and the laser assembly varies from 8mm to 10mm.

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