An optical shaping device

Abstract

The application discloses an optical shaping device and relates to the technical field of laser radars, in particular to the optical shaping device which specifically comprises a laser light source, a bearing substrate, a single-piece free curved mirror and a fixed mounting base; the laser light source is fixed on the bearing substrate, and the single-piece free curved mirror is installed on the light-emitting light path of the laser light source at a preset angle through the fixed mounting base. The single-piece free curved mirror structure can accurately match the characteristics of miniaturization, low power consumption and array output of the VCSEL chip, effectively overcome the problem of high integration difficulty of the traditional multi-lens structure, easily be embedded into consumer electronics and miniature sensing devices, perfectly adapt to the demand of 120-degree large field angle linear laser projection, ensure the stability of the spot shape in the whole field of view, have no distortion and small energy attenuation at the edge of the field of view, fundamentally solve the core defects of poor adaptability of the existing shaping scheme and the VCSEL chip, and meet the use requirements of the near-distance sensing and 3D sensing scene.

Description

Technical Field

[0001] This invention relates to the field of lidar, specifically to an optical shaping device. Background Technology

[0002] Currently, the main line laser shaping solutions in the industry are refractive lens groups, which suffer from high energy loss, complex structure, difficult assembly, and poor environmental stability. Especially for VCSEL chip light sources, which offer advantages such as low power consumption, miniaturization, and arrayed output, and are widely used in consumer electronics and near-field sensing, existing shaping solutions have two major adaptation defects: first, the multi-lens structure cannot match the miniaturization requirements of VCSEL chips, making integration difficult; second, existing solutions cannot accurately adapt to the large field-of-view line laser projection requirements, easily leading to problems such as edge-field distortion and severe energy attenuation.

[0003] However, existing line laser shaping solutions have poor compatibility with VCSEL chips. Traditional refractive lens groups and multi-mirror combinations are bulky and cannot match the low power consumption and miniaturization characteristics of VCSEL chips, making integration difficult and hard to embed into small devices such as consumer electronics and micro-sensors. Furthermore, existing shaping solutions cannot accurately adapt to the large field-of-view line laser projection requirements, easily resulting in problems such as edge-field distortion and severe energy attenuation, failing to meet the high-precision requirements of 3D sensing, machine vision, and other scenarios. In addition, traditional refractive solutions suffer from transmission loss and chromatic aberration, making it difficult to simultaneously achieve linewidth broadening, energy uniformity, divergence angle constraint, and straightness correction for line lasers, resulting in poor spot quality. Summary of the Invention

[0004] This application proposes an optical shaping device with the advantages of strong adaptability, improved light energy utilization, and excellent beam quality, thus solving the technical problems mentioned in the background art.

[0005] To achieve the above objectives, this application adopts the following technical solution: an optical shaping device, comprising a laser source, a carrier substrate, a monolithic freeform surface mirror, and a fixed mounting base; The laser source is fixed on the carrier substrate, and the single freeform surface mirror is installed at a preset angle in the light output path of the laser source through a fixed mounting base; The single-piece freeform surface reflector is a one-dimensional variable curvature freeform surface structure. It adopts a variable curvature design in the length direction and a constant curvature design in the width direction. The reflective surface is equipped with a high-reflection coating.

[0006] Preferably, the laser source is a VCSEL chip or an EEL chip, with an output wavelength set to 808nm, 850nm or 940nm, an output power set to 0.1-0.3W, a beam diameter set to 0.5-3mm, and a divergence angle less than 0.5mrad after collimation.

[0007] Preferably, the supporting substrate is an AlN ceramic substrate or a PCB substrate, used for mechanical support and power supply of the laser light source.

[0008] Preferably, the substrate of the monolithic freeform surface reflector is PC plastic, low-expansion microcrystalline glass, or hard aluminum alloy, with a thickness of 3-6 mm.

[0009] Preferably, the equation of curvature along the linear length of the monolithic freeform surface mirror is y = a·x. 3 +b·x 2 +c·x+d, where a∈[-1×10] -5 -5×10 -6 ],b∈[2×10 -4 5×10 -4 ], c∈[-0.001, 0.001], d∈[0, 0.0005].

[0010] Preferably, the high-reflectivity coating is a metal reflective layer with a dielectric protective film, and the reflectivity is not less than 98.5%.

[0011] Preferably, the fixed mounting base fixes the incident angle of the monolithic freeform surface mirror to 45° with a positioning accuracy of ±0.1°, and is made of ceramic or PCB.

[0012] A line laser shaping method, applied to the aforementioned optical shaping device, includes the following steps: S1, The laser source emits a collimated Gaussian beam; S2. The beam is incident on a single freeform surface mirror at a preset angle; S3. A single freeform surface mirror provides uniform energy compensation and field of view expansion for the beam along the longitudinal direction, and constrains the linewidth and divergence angle along the linear width direction. S4: The beam outputs a 120° wide field of view and highly uniform line laser after a single reflection.

[0013] Preferably, the light beam is incident on the monolithic freeform mirror at an incident angle of 45°.

[0014] Preferably, the shaped line laser has a uniformity of not less than 90% within a 120° field of view, with no edge distortion or significant energy attenuation.

[0015] The present invention has the following beneficial effects: 1. This invention adopts a monolithic freeform surface reflective structure, which can accurately match the miniaturization, low power consumption and array output characteristics of VCSEL chips. It effectively overcomes the problem of difficult integration of traditional multi-lens structures, and can be easily embedded in consumer electronics and micro-sensing devices. At the same time, it can perfectly adapt to the laser projection requirements of a 120° wide field of view, ensuring stable spot shape throughout the entire field of view, no distortion at the edge of the field of view and low energy attenuation. It fundamentally solves the core defect of poor compatibility between existing shaping solutions and VCSEL chips, and meets the usage requirements of near-field sensing and 3D perception scenarios.

[0016] 2. This invention adopts an optical path of single reflection throughout the entire process, eliminating the multi-layer transmission loss and chromatic aberration problems of refractive lens groups. The reflector is equipped with a customized high-reflectivity coating with a reflectivity of no less than 98.5%, maximizing the retention of the light source output energy. Compared with the traditional refractive line laser shaping solution, the light energy utilization rate can be improved by 15%-30%. Even under the low power output conditions of 0.1-0.3W of VCSEL chip, it can still obtain sufficiently strong shaping light, significantly improving the light energy utilization efficiency and better adapting to low power consumption and long battery life application scenarios.

[0017] 3. This invention consists only of a VCSEL light source, a carrier substrate, a single freeform surface mirror, and a miniature mounting base. It contains no redundant optical components, reducing the number of parts by more than 70% compared to traditional multi-lens and multi-mirror solutions. The overall structure is highly simplified, with the mirror thickness only 3-6mm. Combined with the miniature high-precision base, the overall size is compact and can be directly integrated into miniaturized VCSEL devices. During assembly, the incident angle is fixed at 45° with a positioning accuracy of ±0.1°. Assembly is completed in one step without secondary adjustments, significantly improving integration efficiency.

[0018] 4. This invention achieves uniform beam energy compensation and precise divergence angle constraint within a 120° wide field of view through the optimized design of a one-dimensional variable curvature freeform surface reflector. After shaping, the uniformity of the line spot is not less than 90%, with high straightness, no speckle, and no bending deformation. It can simultaneously achieve linewidth broadening, energy homogenization, divergence angle constraint, and straightness correction of the line laser, effectively improving the problem of poor spot quality in traditional solutions and fully meeting the application scenarios with high spot accuracy requirements such as 3D sensing and machine vision.

[0019] 5. This invention eliminates the complex components of traditional solutions, such as refractive lenses, homogenizing plates, and multiple reflectors. It uses only a single reflector with a simple base to complete the shaping process, significantly reducing the number of components. The reflector can be integrally injection molded from PC material, resulting in a simple manufacturing process and high yield. Simultaneously, the assembly process is simplified, requiring no complex adjustments, significantly reducing processing and assembly costs. The overall solution is suitable for standardized mass production, effectively controlling costs for large-scale applications and better adapting to cost-sensitive large-scale application scenarios such as consumer electronics. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the structure of the monolithic reflective line laser shaping method of the present invention; Figure 2 This is a front view of the monolithic reflective line laser shaping method of the present invention.

[0021] In the diagram: 1. VCSEL chip; 2. Supporting substrate; 3. Monolithic freeform surface mirror. Detailed Implementation

[0022] The technical solution of the present invention will be clearly and completely described below with reference to preferred embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] like Figure 1 and Figure 2 The present invention provides an optical shaping device, including a laser light source, a carrier substrate 2, a single freeform surface mirror 3, and a fixed mounting base.

[0024] The laser source uses VCSEL chip 1, or an EEL laser source can be selected; the chip is a single-emission or array-type VCSEL chip 1, with an output wavelength of 808nm, 850nm or 940nm, and an output power of 0.1-0.3W, suitable for low-power scenarios; it outputs a collimated Gaussian beam with a beam diameter of 0.5-3mm, a native divergence angle of 15°-30°, and a divergence angle of <0.5mrad after preliminary collimation.

[0025] The carrier substrate 2 is made of AlN ceramic substrate, but PCB substrate or other substrates can also be used. It mainly serves as a chip carrier and power supply.

[0026] The substrate of the monolithic reflective shaping mirror is made of PC material through one-piece injection molding, but low-expansion microcrystalline glass, hard aluminum alloy, etc. can also be selected. The surface structure is a one-dimensional variable curvature free-form surface, with variable curvature only in the laser line length direction and constant curvature in the line width direction. The curvature equation in the line length direction is y=a·x 3 +b·x 2 +c·x+d, where a∈[-1×10] -5 -5×10 -6 ],b∈[2×10 -4 5×10 -4c∈[-0.001, 0.001], d∈[0, 0.0005], uniform energy compensation within a 120° field of view is achieved through Zemax optical simulation optimization; the radius of curvature R in the linewidth direction is constant, constraining the linewidth and divergence angle, adapting to the beam characteristics of VCSEL chip 1; the reflective coating is a customized anti-reflective film for the mainstream wavelength of VCSEL chip 1, with a reflectivity ≥98.5%; the film structure is substrate + metal reflective layer + dielectric protective film, adapting to the low power and high stability requirements of VCSEL; the reflector thickness is 3-6mm, the effective reflective surface length is the line laser design length plus 10% margin, and the width is ≥4mm.

[0027] The fixed mounting base adopts a high-precision micro base, which is compatible with the miniaturized size of VCSEL chip 1 and single reflective shaping mirror. The incident angle of the reflector is fixed at 45°, the positioning accuracy is ±0.1°, and the material is ceramic or PCB. It has the ability to resist vibration and temperature drift. No secondary debugging is required after one-time assembly, which is suitable for standardized mass production.

[0028] The line laser shaping method based on the above device is as follows: VCSEL chip 1 emits a near-infrared light source, and the beam is incident on a monolithic freeform surface mirror 3 at an incident angle of 45°. The mirror performs uniform energy compensation and field of view expansion on the beam in the linear length direction to achieve a 120° large field of view output. The line width and divergence angle are constrained by constant curvature in the linear width direction. After a single high-reflection, the beam is emitted to form a uniform, distortion-free, and straight line laser spot. The assembly and positioning maintain the incident angle of the mirror at 45° and the positioning accuracy at ±0.1° to achieve stable output without adjustment.

[0029] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention. The invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An optical shaping device, characterized in that: It includes a laser source, a carrier substrate (2), a single freeform surface mirror (3), and a fixed mounting base; The laser source is fixed on the carrier substrate (2), and the single freeform surface reflector (3) is installed at a preset angle on the light output path of the laser source through a fixed mounting base; The single-piece freeform surface reflector (3) is a one-dimensional variable curvature freeform surface structure. The length direction adopts a variable curvature design, the width direction adopts a constant curvature design, and the reflective surface is provided with a high-reflection coating.

2. The optical shaping device according to claim 1, characterized in that: The laser source is a VCSEL chip (1) or an EEL chip, with an output wavelength set to 808nm, 850nm or 940nm, an output power set to 0.1-0.3W, a beam diameter set to 0.5-3mm, and a divergence angle less than 0.5mrad after collimation.

3. The optical shaping device according to claim 1, characterized in that: The carrier substrate (2) is an AlN ceramic substrate or a PCB substrate, used for mechanical support and power supply of the laser light source.

4. The optical shaping device according to claim 1, characterized in that: The substrate of the single freeform surface reflector (3) is PC plastic, low-expansion microcrystalline glass or hard aluminum alloy, and the thickness is set to 3-6mm.

5. The optical shaping device according to claim 1, characterized in that: The equation of curvature along the linear direction of the monolithic freeform surface mirror (3) is y = a·x 3 +b·x 2 +c·x+d, where a∈[-1×10] -5 -5×10 -6 ],b∈[2×10 -4 5×10 -4 ], c∈[-0.001, 0.001], d∈[0, 0.0005].

6. The optical shaping device according to claim 1, characterized in that: The high-reflectivity coating is a metal reflective layer with a dielectric protective film, and its reflectivity is not less than 98.5%.

7. The optical shaping device according to claim 1, characterized in that: The fixed mounting base fixes the incident angle of the single freeform surface reflector (3) to 45° with a positioning accuracy of ±0.1°, and is made of ceramic or PCB.

8. A line laser shaping method, applied to the optical shaping apparatus according to any one of claims 1-7, characterized in that, Includes the following steps: S1, The laser source emits a collimated Gaussian beam; S2. The beam is incident on a single freeform surface mirror (3) at a preset angle. S3, Single freeform surface mirror (3) performs uniform energy compensation and field of view expansion for the beam in the long direction, and constrains the line width and divergence angle in the wide direction; S4: The beam outputs a 120° wide field of view and highly uniform line laser after a single reflection.

9. The line laser shaping method according to claim 8, characterized in that: The beam is incident on a single freeform surface mirror (3) at an incident angle of 45°.

10. The line laser shaping method according to claim 8, characterized in that: The shaped line laser exhibits a uniformity of no less than 90% within a 120° field of view, with no edge distortion or significant energy attenuation.

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