Lens-free beam shaping apparatus and method based on parabolic concave reflecting mirror, and application

Abstract

Disclosed in the present invention are a lens-free beam shaping apparatus and method based on a parabolic concave reflecting mirror, and application. The shaping apparatus comprises a divergent beam light source or a parallel beam light source, a rotational parabolic concave reflecting mirror, a flat transmission inclined window and / or a flat reflecting mirror, and a base, wherein the emission point of the divergent beam light source or the convergence point of the parallel beam light source is located at the focal point of the rotational parabolic concave reflecting mirror; the off-axis angle between a central line of a divergent beam and a parallel beam reflected by the rotational parabolic concave reflecting mirror is smaller than 90°; and the included angle between a reflecting surface of the flat reflecting mirror and the central line of incidence of the divergent beam or the parallel beam is 45°. In the present invention, the configuration of a rotational parabolic concave reflecting mirror combined with a 45° flat reflecting mirror can serve as a direct replacement for collimating lenses or detector converging lenses in the prior art, directly avoiding interference noise caused by reflections from the surfaces of optical elements during the use of the collimating lenses or converging lenses, greatly improving measurement accuracy, while also reducing mounting difficulty and mounting costs.

Description

Lensless beam shaping device based on parabolic concave reflector, method and application Technical Field

[0001] The present invention relates to the technical field of optical equipment, and in particular to a lensless beam shaping device based on a parabolic concave reflector, a method and an application thereof. Background Art

[0002] Currently, commercial semiconductor lasers all use a total reflection waveguide structure. This structure has a narrow laser resonator, an asymmetric active layer mode cross section, and a very small size. Due to the diffraction effect, its far-field spot is both asymmetric and has a large beam divergence angle, forming a light cone with an elliptical cross section, resulting in a fast-axis divergence angle of up to 50-60° and a slow-axis divergence angle of about 30-40°. In order to correct the asymmetry of the far-field divergence angle of semiconductor lasers in the horizontal and vertical directions, Serkan et al. proposed the design of a dual-mirror collimation system for the fundamental mode Gaussian beam emitted from an aspheric point source in "Optical beam-shaping design based on aspherical lenses for circularization, collimation, and expansion of elliptical laser beams" (Appl Opt. 2008 Jan 10; 47(2): 230-41 Mert Serkan, Hulya Kirkici). In the paper “Design Method of High-Power Semiconductor Laser Beam Shaping System with Variable Divergence Angle - Laser and Optoelectronics Progress” (49,071401 (2012), Fei Bing et al. proposed a design method for HPLD beam shaping using aspheric cylindrical lenses and long-focus plano-convex cylindrical lenses, which achieved the goal of continuously changing the beam divergence angle within a certain range.

[0003] Mid-infrared laser light sources, such as QCL lasers, have great advantages in high-sensitivity gas detection. When mid-infrared lasers are used in miniaturized laser gas sensors, the divergent output beam of the laser light source needs to be converted into a parallel beam. The existing mainstream technology is to partially solve the collimation problem of small laser packaging by selecting optical materials that match the laser wavelength and designing appropriate collimating lenses. Although the mirror reflection of the lens can be reduced by coating, a certain amount of reflected light from the surface of the lens will always be reflected into the resonant cavity of the laser, thereby generating interference ripples and forming interference noise in precision measuring instruments. This noise not only reduces the measurement accuracy but also affects the long-term stability of the measuring instrument.

[0004] One of the conventional optical designs is to use a parabolic concave reflector to collimate a laser light source into a parallel beam. In the design, the laser light source can be set at the focus of the parabola, and the light beam emitted from the laser can be reflected by the parabolic reflector to form a parallel beam. Compared with lenses, the use of axial parabolic reflectors will not produce interference in the laser light source, and will not produce the absorption loss of the lens. Conventional parabolic reflectors can be divided into rotating parabolic reflectors, annular rotating parabolic reflectors and cylindrical parabolic reflectors according to their shape. These rotating parabolic reflectors can be applied to different types of light sources, such as flashlight bulbs, LED lamp beads, and some instrumentation applications that require the convergence of beam energy.

[0005] As we all know, the cross-section of the beam emitted by a typical FP laser is elliptical, meaning that the divergence angles along the fast and slow axes are different. Therefore, in design, it is necessary to consider both how to reflect the divergent light into a parallel beam using a rotating parabolic concave reflector, and how to adjust the beam's elliptical cross-section to a circular or approximately circular cross-section. In other words, the beam energy along the fast axis should be collimated and reflected into a parallel beam as much as possible, forming a relatively ideal parallel beam.

[0006] Therefore, the main purpose of the present invention is to solve the problem of how to use a combination of a parabolic reflector and a plane reflector to adjust the laser elliptical divergent beam into a collimated beam parallel to the laser optical axis, thereby reducing interference noise in a variety of different practical applications. Summary of the Invention

[0007] In order to solve the technical problems such as the unavoidable interference noise caused by the use of lenses in the above-mentioned prior art, one of the purposes of the present invention is to provide a lens-free beam shaping device based on a rotating parabolic concave reflector, by arranging a rotating parabolic concave reflector on a base, and matching it with a plane transmission oblique window and / or a 45° plane reflector, and adjusting the off-axis angle between the center line of the divergent light beam emitted by the divergent light beam light source and the parallel light beam after reflection by the rotating parabolic concave reflector to be less than 90°; in this way, the divergent light beam can be collimated and shaped to form a collimated light beam perpendicular to or parallel to the optical axis of the divergent light beam, and can also be used for the purpose of improving the quality of the light. The invention shapes a divergent light beam with an elliptical cross section into a parallel light beam with an approximately circular cross section; and according to the principle of reversible optical path, the present invention can also converge and shape the received parallel light beam. Therefore, the present invention can directly replace the collimating lens or the converging lens of the detector in the prior art through a simple structure. Therefore, in the process of collimating or converging the light beam, the interference noise caused by the reflection of the optical element surface due to the use of the collimating lens or the converging lens is directly avoided, thereby greatly improving the measurement accuracy. At the same time, it avoids a series of alignment operations to ensure accuracy during the installation of the collimating lens, greatly reducing the difficulty of installation.

[0008] A second object of the present invention is to provide a shaping method of a lensless beam shaping device based on a rotating parabolic concave reflector.

[0009] A third object of the present invention is to provide an application of a lensless beam shaping device based on a rotating parabolic concave reflector.

[0010] One of the objectives of the present invention is achieved through the following technical solution: a lensless beam shaping device based on a parabolic concave reflector, used for collimating a divergent beam or converging a parallel beam; the beam shaping device includes a divergent beam light source or a parallel beam light source, a beam shaping component for adjusting the direction of the beam path, and a base for mounting the beam shaping component; the beam shaping component includes a rotating parabolic concave reflector, and the rotating parabolic concave reflector is concavely arranged on the base; the emission point of the divergent beam light source or the convergence point of the parallel beam emitted by the parallel beam light source is located at the focus of the rotating parabolic concave reflector; the off-axis angle between the center line of the divergent beam emitted by the divergent beam light source and the parallel beam after reflection by the rotating parabolic concave reflector is less than or equal to 90°;

[0011] The beam shaping assembly further includes a plane transmission oblique window and / or a plane reflector disposed on the base; the plane transmission oblique window and / or the plane reflector are located on the reflection path of the light beam; the angle between the reflective surface of the plane reflector and the center line of incidence of the divergent light beam or the parallel light beam is 45°; an angle is formed between the plane transmission oblique window and the parallel light beam;

[0012] The divergent light beam emitted by the divergent light beam light source is reflected by the rotating parabolic concave reflector and then emitted as a parallel light beam through the plane transmission oblique window, or it is reflected by the plane reflector and then emitted as a collimated light beam parallel to the center line of the divergent light beam; or according to the principle of reversible optical path, the parallel light beam emitted by the parallel light beam light source and parallel to the main axis of the rotating parabolic concave reflector is incident and then reflected by the plane transmission oblique window or the plane reflector and then converged to a convergence point through the rotating parabolic concave reflector.

[0013] Furthermore, the base is a rectangular parallelepiped base; the rotational parabolic concave reflector is a concave rotating body that is rotated 180° about the parabola center axis and is integrally formed on the rectangular parallelepiped base.

[0014] Furthermore, the off-axis angle between the center line of the divergent beam emitted by the divergent beam light source and the parallel beam reflected by the rotating parabolic concave reflector is 80-90°; the fast axis of the divergent beam light source is parallel to the main axis of the rotating parabolic concave reflector.

[0015] Furthermore, the rotational parabolic concave reflector and / or the plane reflector are made of mirror steel or other metals, and the reflective surface is coated with a metal reflective film.

[0016] Furthermore, the surface of the metal reflective film on the reflective surface is coated with a silicon dioxide protective film.

[0017] The second object of the present invention can be achieved by the following technical solution: A beam shaping method of the above-mentioned lensless beam shaping device based on a parabolic concave reflector comprises the following steps:

[0018] S1: setting the light source exit point of the divergent light beam to be collimated and shaped at the focus of the rotating parabolic concave reflector;

[0019] S2: adjusting the angle between the center line of the divergent beam of the divergent beam light source and the main axis of the rotating parabolic concave reflector so that the off-axis angle between the center line of the divergent beam emitted by the divergent beam light source and the parallel beam reflected by the rotating parabolic concave reflector is less than 90°;

[0020] S3: The fast axis of the divergent beam light source is parallel to the main axis of the rotating parabolic concave reflector. The divergent beam light source emits a divergent beam and is incident on the rotating parabolic concave reflector. The parallel beam of the divergent beam after being reflected by the rotating parabolic concave reflector can be emitted from the plane transmission oblique window, or it can be reflected by a 45° plane reflector to form a collimated beam parallel to the optical axis of the divergent beam.

[0021] Furthermore, in S2, the off-axis angle between the parallel beam of the divergent beam emitted by the divergent beam light source and the center line of the divergent beam after being reflected by the rotating parabolic concave reflector is 80-90°.

[0022] The second object of the present invention can also be achieved by the following technical solution: a beam shaping method of the above-mentioned lensless beam shaping device based on a parabolic concave reflector, comprising the following steps:

[0023] S1: setting the convergence point of the parallel light beam to be converged and shaped emitted by the parallel light beam light source at the focus of the rotating parabolic concave reflector;

[0024] S2: Adjusting the parallel light beam to be parallel to the principal axis of the rotating parabolic concave reflector so that the off-axis angle between the center line of the convergent light beam emitted by the parallel light beam light source and the original incident parallel light beam after being reflected by the rotating parabolic concave reflector is less than or equal to 90°;

[0025] S3: The parallel light beam emitted by the parallel light beam light source is incident, reflected by the plane transmission oblique window or the plane reflector, and then reflected by the rotating parabolic concave reflector and converged to the convergence point.

[0026] Furthermore, in S2, the off-axis angle between the center line of the convergent beam of the parallel beam emitted by the parallel beam light source after being reflected by the rotating parabolic concave reflector and the center line of the original incident parallel beam or the parallel beam after being reflected by the plane reflector is 80-90°.

[0027] The third object of the present invention can be achieved through the following technical solutions:

[0028] (1) Application of a lensless beam shaping device based on a parabolic concave reflector in a laser sensor in which the collimated laser beam is parallel to the optical axis of the original divergent beam: the laser sensor further comprises a packaging device and a laser chip and a heat sink arranged in the packaging device; the beam shaping device is adapted to be installed between the laser chip and the light outlet of the packaging device; the vertical distance from the bottom surface of the base to the focus of the rotating parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink to the laser beam exit point of the laser chip; the plane reflector is arranged at the parallel beam exit point of the rotating parabolic concave reflector, and the plane transmission oblique window is arranged corresponding to the light outlet of the packaging device; the laser divergent beam emitted by the laser chip is reflected by the rotating parabolic concave reflector, and then reflected by a 45° plane reflector to form a collimated beam parallel to the optical axis of the original divergent beam, which is emitted from the plane transmission oblique window.

[0029] (2) Application of a lensless beam shaping device based on a parabolic concave reflector in a laser sensor in which the collimated laser beam is perpendicular to the optical axis of the original divergent beam: the laser sensor further comprises a packaging device and a laser chip and a heat sink arranged in the packaging device; the beam shaping device is adapted to be installed between the laser chip and the light outlet of the packaging device; the vertical distance from the bottom surface of the base to the focus of the rotating parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink to the laser beam exit point of the laser chip; the plane transmission oblique window is arranged at the parallel beam exit point of the rotating parabolic concave reflector; the laser divergent beam emitted by the laser chip is reflected by the rotating parabolic concave reflector to form a collimated beam parallel to the main axis of the rotating parabolic concave reflector, which is emitted from the plane transmission oblique window and the light outlet.

[0030] (3) Application of a lensless beam shaping device based on a parabolic concave reflector in a laser sensor in which the collimated laser beam is perpendicular to the optical axis of the original divergent beam: the laser sensor also includes a packaging device and a laser chip and a heat sink arranged in the packaging device; the packaging device is a TO-CAN packaging device, including a circular or rectangular TO base for mounting the laser chip and the heat sink; the base is arranged on the TO base, and the plane transmission oblique window is arranged at the parallel beam exit of the rotating parabolic concave reflector, corresponding to the light outlet of the TO-CAN packaging device; the laser divergent beam emitted by the laser chip is reflected by the rotating parabolic concave reflector to form a collimated beam parallel to the TO base, which is emitted from the plane transmission oblique window and the light outlet.

[0031] (4) Application of a lensless beam shaping device based on a parabolic concave reflector in a detector that receives parallel light beams and performs convergence shaping: the detector photosensitive surface is set at the focus of the rotating parabolic concave reflector; the plane reflector is set at the entrance of the parallel light beam of the rotating parabolic concave reflector; after the parallel light beam is incident, it is reflected by the plane reflector and then reflected by the rotating parabolic concave reflector and converges onto the detector photosensitive surface.

[0032] (5) Application of a lensless beam shaping device based on a parabolic concave reflector in a TO-CAN packaged detector that receives parallel light beams and performs convergence shaping: the TO-CAN package device includes a circular or rectangular TO base, the base is arranged on the TO base, the detector photosensitive surface is arranged at the focus of the rotating parabolic concave reflector, the plane transmission oblique window is arranged at the parallel light beam entrance of the rotating parabolic concave reflector, and corresponds to the light inlet of the TO-CAN package device; after the parallel light beam is incident, it passes through the plane transmission oblique window and then is reflected by the rotating parabolic concave reflector and converges onto the detector photosensitive surface.

[0033] Compared with the prior art, the present invention has at least the following beneficial effects:

[0034] 1. The present invention sets a rotating parabolic concave reflector on a base, and is matched with a plane transmission oblique window and / or a 45° plane reflector, as well as an adjustable angle between the center line of the divergent light beam of the divergent light beam light source and the main axis of the rotating parabolic concave reflector. The off-axis angle between the center line of the divergent light beam emitted by the divergent light beam light source and the parallel light beam after reflection by the rotating parabolic concave reflector is less than 90°; in this way, the divergent light beam can be collimated and shaped, and a collimated light beam perpendicular to or parallel to the optical axis of the divergent light beam can be formed by not using or using a 45° reflector; and according to the principle of reversible optical path, the present invention can also converge and shape the received parallel light beam. Therefore, the present invention can directly replace the collimating lens or the converging lens of the detector in the prior art with a simple structure. Therefore, in the process of collimating or converging the light beam, the interference noise caused by the reflection of the optical element surface due to the use of the collimating lens or the converging lens is directly avoided, thereby greatly improving the measurement accuracy. At the same time, a series of alignment operations to ensure the accuracy during the installation of the collimating lens are avoided, greatly reducing the installation difficulty;

[0035] 2. Since the present invention adopts a rotating parabolic concave reflector for collimation, the entire beam collimation system is insensitive to the wavelength of the laser light source. The same reflective collimation system can be applied to laser light sources of different wavelengths. Therefore, the present invention can be used for the collimation of different laser wavelengths, thereby realizing the detection of different gases, greatly expanding the application range of gas detection and reducing application restrictions.

[0036] 3. Furthermore, because the mirror surfaces of the rotating parabolic concave reflector and the plane reflector absorb very little energy from the light beam, the collimated light beam can be focused without chromatic aberration, eliminating the phase delay and absorption loss caused by transmissive optical elements. Therefore, the beam shaping device of the present invention can also be used in the collimation of high-power and even ultra-high-power lasers, further expanding the scope of application and reducing application limitations.

[0037] 4. On the other hand, the present invention is extremely convenient to install. Taking the application of laser sensors as an example, after the laser chip, heat sink, TEC and other optical components of the sensor are installed, the vertical distance from the bottom surface of the heat sink (or other components that can determine the position of the laser chip beam exit point, such as the inner bottom surface of the packaging device) to the laser beam exit point of the laser chip is determined. The vertical distance from the bottom surface of the base to the focus of the rotating parabolic concave reflector can be designed as needed. As long as the above two distances are ensured to be equal, the installation of the beam shaping device of the present invention can be completed quickly, and the exit point of the divergent beam light source can be simultaneously ensured to be located at the focus of the rotating parabolic concave reflector, thereby avoiding the error of the existing technology in aligning the focus and the axis during the lens installation process, greatly reducing the installation difficulty and manufacturing cost of the collimation system. Similarly, when the present invention is applied to a detector, the detector photosensitive surface and the focus of the rotating parabolic concave reflector can also be quickly aligned, thereby quickly completing the installation of the beam converging and shaping device.

[0038] 5. Another outstanding advantage of the lensless beam shaping device of the present invention is that it can adjust the size of the laser beam spot in the fast axis direction: since the rotating parabolic concave reflector of the present invention is a semicircular parabolic mirror formed by rotating the parabola 180 degrees around the main axis with the main axis of the parabola as the central axis, the fast axis of the laser divergent beam is set to be parallel to the main axis of the rotating parabolic concave reflector, and the off-axis angle between the center line of the divergent beam (light cone) and the parallel beam after reflection by the rotating parabolic concave reflector is set to be slightly less than 90°. This setting is because for light cones with the same divergence angle, if the angle (off-axis angle) between the center line of the light cone and the parallel beam after reflection is different, the fast axis of the laser divergent beam is set to be parallel to the main axis of the rotating parabolic concave reflector. The diameter of the reflected light spot formed by the rotating parabolic concave reflector in the fast axis direction will be different. When the off-axis angle gradually decreases from 90°, the diameter of the reflected light spot also gradually decreases. By utilizing this physical property of the rotating parabolic concave reflector and adjusting the center line of the laser's light cone and the collimated light beam to form an angle less than 90°, the diameter of the light spot in the fast axis direction can be reduced, thereby achieving the goal of collimating the laser divergent beam with an elliptical cross-section into a parallel beam with a nearly circular cross-section. Then, a 45° plane reflector is used to reflect the parallel beam to the coaxial direction of the laser, which facilitates the installation and adjustment of the laser. That is, the present invention can simultaneously achieve the functions of beam collimation and light spot size adjustment, achieving multiple goals at one stroke.

[0039] 6. Furthermore, the application of the beam shaping device of the present invention in a TO-CAN packaged laser or detector will greatly improve the convenience of TO-CAN packaging, avoiding the strict packaging limitations of the prior art that require precise alignment of the focus and axis when using a collimating lens or converging lens, thereby greatly improving packaging efficiency and accuracy.

[0040] 7. In the development of miniaturization and micro-miniaturization in the field of precision detection sensors, the lensless beam shaping device of the present invention is a technological breakthrough in traditional lens beam collimation or beam convergence, which can greatly expand the application scope of optical collimation systems. As long as the laser beam after collimation meets the collimation requirements of being parallel or perpendicular to the optical axis of the original divergent beam, it can be adapted for application. According to the principle of reversible optical path, the present invention can also be widely used as a beam convergence system in various detectors, with greatly improved accuracy and significantly reduced manufacturing costs, thus achieving good economic benefits and being suitable for large-scale promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] FIG1 is a schematic diagram of a light cone emitted by a general laser divergent beam;

[0042] FIG2 is a schematic diagram of the overall structure of a rotating parabolic concave reflector of a lensless beam shaping device based on a parabolic concave reflector according to Examples 1-9 of the present invention;

[0043] FIG3 is a schematic diagram of the collimated optical path trajectory of the divergent light beam of the parabolic concave reflector of the parabolic concave reflector-based lensless beam shaping device according to embodiments 1-3, 6-7 of the present invention after being reflected by the parabolic concave reflector;

[0044] FIG4 is a schematic diagram of the convergent optical path trajectory of the divergent light beam of the lensless beam shaping device based on the parabolic concave reflector according to Examples 4-5 and 8-9 of the present invention after being reflected by the rotating parabolic concave reflector;

[0045] FIG5 is a schematic diagram of the overall structure of a combination of a rotating parabolic concave reflector and a 45° plane mirror of a lensless beam shaping device based on a parabolic concave reflector according to Examples 6-9 of the present invention;

[0046] FIG6 is a schematic diagram of the collimated optical path of a divergent light beam of a combination of a rotating parabolic concave reflector and a 45° plane mirror in a lensless beam shaping device based on a parabolic concave reflector according to Example 6-7 of the present invention, after being reflected by the rotating parabolic concave reflector and then by the plane reflector;

[0047] FIG7 is a schematic diagram of the convergent optical path of a parallel light beam of a combination of a rotating parabolic concave reflector and a 45° plane mirror in a lensless beam shaping device based on a parabolic concave reflector in Example 8-9 of the present invention, which is reflected by the plane reflector and then reflected by the rotating parabolic concave reflector;

[0048] FIG8 is a schematic diagram showing the overall structure of a combination of a rotating parabolic concave reflector and a 45° plane mirror of a lensless beam shaping device based on a parabolic concave reflector according to embodiments 6-7 of the present invention, and a collimated optical path of a divergent light beam after it is reflected by the rotating parabolic concave reflector and then by the plane reflector;

[0049] FIG9 is a schematic diagram showing the overall structure of a combination of a rotating parabolic concave reflector and a 45° plane mirror of a lensless beam shaping device based on a parabolic concave reflector according to embodiments 8-9 of the present invention, and a schematic diagram showing the convergence optical path of a parallel diverging light beam after being reflected by the rotating parabolic concave reflector and then by the plane reflector;

[0050] FIG10 is a schematic diagram of the overall mounting structure of a laser sensor comprising a combination of a rotating parabolic concave reflector and a 45° plane mirror in a lensless beam shaping device based on a parabolic concave reflector according to Embodiments 6-7 of the present invention, and a schematic diagram of the collimated optical path of a divergent light beam after it is reflected by the rotating parabolic concave reflector and then by the plane reflector;

[0051] FIG11 is a schematic diagram of the overall mounting structure of a detector composed of a rotating parabolic concave reflector and a 45° plane mirror in the lensless beam shaping device based on a parabolic concave reflector according to Embodiments 8-9 of the present invention, and a schematic diagram of the convergent optical path of a parallel diverging light beam reflected by the rotating parabolic concave reflector and then by the plane reflector;

[0052] FIG12 is a schematic diagram of the packaging structure of a TO-CAN packaged laser sensor of a lensless beam shaping device based on a parabolic concave reflector according to embodiments 1 and 3 of the present invention, and a light path trajectory of the laser beam after the divergent beam is collimated, which is perpendicular to the optical axis of the original divergent beam;

[0053] FIG13 is a schematic diagram of the packaging structure of the detector of the TO-CAN package and the convergent optical path trajectory of the parallel light beam of the lensless beam shaping device based on the parabolic concave reflector in Examples 4 and 5 of the present invention.

[0054] In the picture:

[0055] 10. Beam shaping device; 20. Laser sensor; 201. Packaging device; 202. Laser chip; 203. Heat sink; 204. Light outlet; 205. TO base; 30. Detector; 301. Photosensitive surface; 302. TO base; 303. Light inlet;

[0056] 1. Divergent beam light source; 11. Light source exit point; 2. Parallel beam light source; 21. Convergence point; 3. Beam shaping assembly; 31. Rotating parabolic concave reflector; 311. Reflecting surface; 32. Planar transmission oblique window forming a certain oblique angle with the parallel beam; 33. Plane reflector; 331. Reflecting surface; 4. Base;

[0057] F, focus of the rotating parabolic concave reflector; h, principal axis of the rotating parabolic concave reflector; L1, centerline of the diverging light beam; L2, centerline of the parallel light beam; α, off-axis angle between the centerline of the diverging light beam and the parallel light beam after reflection from the rotating parabolic concave reflector; β, angle between the reflective surface of the plane reflector and the centerline of the incident diverging light beam or parallel light beam; θ⊥ , laser fast axis. DETAILED DESCRIPTION

[0058] To facilitate understanding of the present invention, the technical solutions and advantages of the invention are further described in detail below in conjunction with the accompanying drawings and embodiments. The specific structure and features of the present invention are described below in an illustrative manner and should not constitute any limitation to the present invention. At the same time, any of the technical features mentioned below (including implicit or disclosed), as well as any technical features directly displayed or implicit in the drawings, can be further combined or deleted between these technical features to form more other embodiments that may not be directly or indirectly mentioned in the present invention. The accompanying drawings show preferred embodiments of the present invention. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to enable a more thorough and comprehensive understanding of the disclosure of the present invention.

[0059] It should be noted that the construction and arrangement of the present invention shown in a number of different exemplary embodiments are merely illustrative. Although only a few embodiments are described in detail in this disclosure, it should be readily understood by those who refer to this disclosure that many modifications are possible (e.g., the size, structure, shape, and proportion of various elements) without substantially departing from the novel teachings and advantages of the subject matter described in this application. The order or sequence of any process or method steps can be changed or reordered according to alternative embodiments. In the claims, any "means plus function" clause is intended to cover the structure of the performance of the function described herein, and is not only structurally equivalent but also equivalent structures. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the exemplary embodiments without departing from the scope of the invention.

[0060] Example 1 Lensless beam collimation based on parabolic concave reflector and planar transmission oblique window

[0061] As shown in Figures 1-3 and 12, this embodiment 1 provides a lensless beam shaping device 10 based on a parabolic concave reflector for collimating and shaping a divergent light beam. The lensless beam shaping device 10 includes a divergent light beam source 1, a beam shaping assembly 3 for adjusting the direction of the light beam path, and a base 4 for mounting the beam shaping assembly 3. In this embodiment, the divergent light beam source 1 is a light source without a focusing or collimating lens, including but not limited to FP lasers, DFB lasers, QCL lasers, etc. Any light source that meets the above requirements is applicable.

[0062] The beam shaping assembly 3 includes a rotating parabolic concave reflector 31, which is concavely disposed on the base 4. Specifically, the rotating parabolic concave reflector 31 is a semicircular parabolic concave reflector formed by rotating the parabola 180° around the main axis h, with the main axis h of the parabola as the central axis. The exit point 11 of the divergent beam light source is located at the focus F of the rotating parabolic concave reflector. The off-axis angle α between the center line L1 of the divergent beam emitted by the divergent beam light source 1 and the parallel beam after reflection by the rotating parabolic concave reflector is less than 90°.

[0063] Preferably, the off-axis angle α between the center line L1 of the divergent light beam emitted by the divergent light beam source and the parallel light beam reflected by the rotating parabolic concave reflector is 80-90°; the fast axis θ of the divergent light beam source is ⊥ Parallel to the principal axis h of the rotational parabolic concave reflector.

[0064] To further refine, the divergent beam emitted by the laser (divergent beam source 1) is a light cone with an elliptical cross section. The angle between the center line L1 of the light cone and the collimated beam is usually called the off-axis angle α. Therefore, the laser outlet 11 (or the top of the light cone) is placed at the focus F of the rotating parabolic concave reflector, and the fast axis θ of the laser is ⊥ It is set to be parallel to the main axis h of the parabolic mirror, and the off-axis angle α of the light beam is slightly less than 90°; in this way, the two physical properties of the rotating parabolic concave reflector can be used to collimate and shape the divergent light cone with an elliptical cross section:

[0065] The first physical property is that any light beam with any divergence angle emitted from a laser at the focus of a rotating parabolic concave reflector will be reflected by the rotating parabolic concave reflector to form a parallel beam parallel to the principal axis of the reflector. The second physical property is that for light cones with the same divergence angle, if the angle (off-axis angle) between the centerline of the light cone and the parallel beam after reflection from the rotating parabolic concave reflector is different, the diameter of the reflected light spot formed by reflection from the rotating parabolic concave reflector will be different. As the off-axis angle gradually decreases from 90°, the diameter of the reflected light spot also gradually decreases. By utilizing this physical property, the diameter of the light spot in the fast axis direction can be reduced by adjusting the centerline of the laser light cone and the collimated light beam to form an angle less than 90°, thereby achieving the goal of collimating a divergent light beam with an elliptical cross-section into a parallel light beam with a nearly circular cross-section. In other words, the present invention can simultaneously achieve the functions of beam collimation and adjustment of the light spot size in the laser fast axis direction.

[0066] Preferably, the base 4 is a rectangular base; in the present invention, the base is preferably a rectangular parallelepiped or a cube. The purpose of this setting is to facilitate the design of the vertical distance from the bottom surface of the base to the focus of the rotating parabolic concave reflector, and the flat end surface is more conducive to packaging; in other embodiments, the base 4 can also be designed to be other shapes such as a right-angled trapezoid that can meet the installation requirements of the optical elements of the present invention.

[0067] Preferably, the beam shaping assembly 3 further includes a planar transmission oblique window 32 disposed on the base 4, and the planar transmission oblique window 32 is disposed at the parallel beam exit point of the rotating parabolic concave reflector 31. The divergent laser beam emitted by the divergent beam source is reflected by the rotating parabolic concave reflector to form a collimated beam perpendicular to the optical axis of the original divergent beam, which is then emitted from the planar transmission oblique window 32 at a predetermined angle to the parallel beam.

[0068] Preferably, the parabolic concave reflector 31 is made of mirror-finished steel or other metal, and the reflective surface 311 is coated with a metal reflective film; the metal reflective film on the reflective surface is also coated with a silicon dioxide protective film. In this embodiment, the parabolic concave reflector is formed by stamping mirror-finished steel and then coating it with a reflective film. Because metal films are easily oxidized, discolored, or detached in high-humidity environments, a silicon dioxide protective film is applied to both metal-coated reflective mirror surfaces to isolate the metal films from direct contact with air, preventing oxidation that could affect their optical performance.

[0069] The arrangement of the oblique planar transmission window is further explained. It forms a 5-8° angle with the parallel light beam, further reducing interference and other issues caused by reflections from the window and improving beam shaping accuracy. Furthermore, the rotating parabolic concave reflector and oblique planar transmission window function similarly to a To-can cap, sealing the laser chip or detector photosensitive chip onto the To-can base to accommodate diverse application requirements.

[0070] It should be noted that the planar transmission oblique window can be set to have its inclination angle and direction according to the packaging requirements of the beam shaping device, and can be implemented as long as it can achieve the beneficial effects of the present invention.

[0071] The collimation method of the lensless shaping device based on the parabolic concave reflector and the planar transmission oblique window in this embodiment for light beam collimation includes the following steps:

[0072] S1: setting the light source exit point of the divergent light beam to be collimated at the focus of the rotating parabolic concave reflector;

[0073] S2: adjusting the angle of the center line of the divergent light beam relative to the main axis of the rotating parabolic concave reflector so that the off-axis angle between the center line of the divergent light beam emitted by the divergent light beam light source and the parallel light beam reflected by the rotating parabolic concave reflector is less than 90°;

[0074] S3: The divergent beam light source emits a divergent beam and is incident on the rotating parabolic concave reflector. After the divergent beam is reflected by the rotating parabolic concave reflector, a parallel beam can be emitted from the plane transmission oblique window.

[0075] In S2, the off-axis angle between the center line of the parallel light beam emitted by the parallel light beam and the center line of the original incident parallel light beam after being reflected by the rotating parabolic concave reflector is 80-90°, and the fast axis of the divergent light beam is parallel to the main axis of the rotating parabolic concave reflector.

[0076] This embodiment arranges a rotating parabolic concave reflector on a base, in combination with a plane transmission oblique window, and can adjust the off-axis angle between the center line of the divergent light beam emitted by the divergent light beam source and the parallel light beam after reflection by the rotating parabolic concave reflector to be less than 90°. In this way, the divergent light beam can be collimated and shaped to form a collimated light beam perpendicular to or parallel to the optical axis of the divergent light beam, and the size of the laser spot in the fast axis direction can be reduced.

[0077] Example 2 Application of a lensless beam shaping device based on a parabolic concave reflector and a plane transmission oblique window in a laser sensor in which the collimated laser beam is perpendicular to the optical axis of the original divergent beam

[0078] As shown in Figures 1-3 and 12, this embodiment 2 is the application of the above embodiment 1 in a laser sensor 20 in which the collimated laser beam is perpendicular to the optical axis of the original divergent beam;

[0079] Specifically, the laser sensor 20 of this embodiment 2 further includes a packaging device 201 and a laser chip 202 and a heat sink 203 disposed within the packaging device 201; the beam shaping device 10 is adapted to be installed between the laser chip 201 and the light outlet 204 of the packaging device; the vertical distance from the bottom surface of the base 4 to the focus F of the rotating parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink 203 to the laser beam exit point 11 of the laser chip 201; the planar transmission oblique window 32 is disposed at the parallel beam exit point of the rotating parabolic concave reflector 31;

[0080] In this embodiment, the vertical distance from the bottom surface of the base to the focal point of the parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink to the laser beam exit point of the laser chip. This is intended to ensure that after the laser chip, heat sink, TEC and other optical components of the sensor are installed, the vertical distance from the bottom surface of the heat sink (or other components that can determine the position of the laser chip beam exit point, such as the inner bottom surface of the packaging device) to the laser beam exit point of the laser chip is determined. The vertical distance from the bottom surface of the base to the focal point of the parabolic concave reflector can then be designed as needed. As long as the above two distances are ensured to be equal, the beam shaping device of the present invention can be quickly installed, and the exit point of the divergent beam light source can be simultaneously ensured to be located at the focal point of the parabolic concave reflector. This reduces the error in lens installation in the prior art and greatly reduces the installation difficulty and manufacturing cost of the collimation system.

[0081] The divergent laser beam emitted by the laser chip of the second embodiment is reflected by the rotating parabolic concave reflector to form a collimated beam perpendicular to the optical axis of the original divergent laser beam, which is emitted from the planar transmission oblique window and the light outlet.

[0082] Example 3 Application of a lensless beam shaping device based on a parabolic concave reflector and a plane transmission oblique window in a laser sensor with a collimated laser beam perpendicular to the optical axis of the original divergent beam packaged in a TO-CAN package

[0083] As shown in Figures 1-3 and 12, this embodiment 3 is the application of the above embodiment 2 in a TO-CAN packaged laser sensor;

[0084] Specifically, the packaging device is a TO-CAN base packaging device, including a TO base 205 for mounting the laser chip 201 and the heat sink 203; the base 4 is arranged on the TO base 205, and the plane transmission oblique window 32 is arranged at the parallel light beam exit of the rotating parabolic concave reflector 31 and corresponds to the light outlet of the TO-CAN packaging device 201;

[0085] The center line of the laser divergent beam emitted by the laser chip is perpendicular to the base plane. The divergent beam is reflected by the rotating parabolic concave reflector to form a collimated beam parallel to the TO base plane and is emitted from the plane transmission oblique window and the light outlet.

[0086] Specifically, the installation of the TO-CAN packaged collimated laser can adjust the angles of the base and the rotating parabolic concave reflector and other components of the present invention according to the actual installation angle of the laser chip to ensure that the direction of the collimated light beam meets the requirements.

[0087] Example 4 Lensless beam convergence based on parabolic concave reflector and plane transmission oblique window

[0088] As shown in Figures 1-2, 4, and 13, this embodiment 4 provides a lensless beam shaping device based on a parabolic concave reflector for converging and shaping parallel light beams. The differences between this embodiment 4 and embodiment 1 are as follows:

[0089] (1) The beam shaping device described in this embodiment 4 includes a parallel beam light source 2, the optical path of which is opposite to that of embodiment 1. This embodiment 4 receives parallel beams and converges them;

[0090] (2) The light source of this embodiment 4 is a light source 2 that emits a parallel light beam, and a convergence point 21 (such as a detector photosensitive surface) of the parallel light beam to be converged and shaped is set at the focus F of the rotating parabolic concave reflector;

[0091] (3) The beam converging and shaping method of this embodiment 4 is different and includes the following steps:

[0092] S1: setting the convergence point of the parallel light beam to be converged and shaped emitted by the parallel light beam light source at the focus of the rotating parabolic concave reflector;

[0093] S2: adjusting the parallel light beam to be parallel to the principal axis of the rotating parabolic concave reflector, so that the off-axis angle between the center line of the convergent light beam emitted by the parallel light beam light source and the principal axis of the rotating parabolic concave reflector is less than or equal to 90°;

[0094] S3: The parallel light beam emitted by the parallel light beam light source is incident on the plane transmission oblique window and then directly reflected by the rotating parabolic concave reflector and converged to the convergence point.

[0095] In S2, the off-axis angle α between the center line of the convergent beam of the parallel beam emitted by the parallel beam light source 2 and the center line h of the original incident parallel beam after being reflected by the rotating parabolic concave reflector is 80-90°.

[0096] Example 5 Application of lensless beam convergence based on parabolic concave reflector and planar transmission oblique window in TO-CAN packaged detector

[0097] As shown in Figures 1-2, 4, and 13, this embodiment 5 provides an application of a lensless beam shaping device based on a parabolic concave reflector in a detector 30 packaged in a TO-CAN package; specifically, the detector 30 includes a TO-CAN base packaging device; the TO-CAN packaging device includes a TO base 302, the base 4 is arranged on the TO base 302, the detector photosensitive surface 301 is arranged at the focus F of the rotating parabolic concave reflector 31, and the plane transmission oblique window 32 is arranged at the entrance of the parallel light beam of the rotating parabolic concave reflector 31, and corresponds to the light inlet 303 of the TO-CAN packaging device; after the parallel light beam is incident, it passes through the plane transmission oblique window and then reflected by the rotating parabolic concave reflector and converges onto the detector photosensitive surface 301.

[0098] The light beam converging method is referred to Example 4.

[0099] Example 6 Lensless beam collimation based on parabolic concave reflector and 45° plane reflector

[0100] As shown in Figures 1-2, 5-6, 8, and 10, this embodiment 6 provides a lensless beam shaping device based on a parabolic concave reflector, which is used to collimate and shape a divergent light beam. The difference between this embodiment 6 and embodiment 1 is that:

[0101] The beam shaping assembly 3 further includes a plane reflector 33 disposed on the base 4. The plane reflector 33 is located at the parallel light beam outlet of the rotational parabolic concave reflector 31, and the angle β between the reflective surface 331 of the plane reflector 33 and the center line L2 of the incident divergent light beam or parallel light beam is 45°. The purpose of the plane reflector 33 is to reflect the propagation direction of the parallel light beam into a direction parallel to the optical axis of the original divergent light beam.

[0102] In this embodiment, the plane reflector 33 is disposed within the base 4 and has a three-dimensional hollow structure with a cross-section shaped like an isosceles right triangle (90°, 45°, 45°). The reflective surface is disposed on the plane containing the hypotenuse of the isosceles right triangle, with the planes containing the two right-angled sides corresponding to the parabolic concave reflector and the light outlet, respectively. In other embodiments, the plane reflector may be disposed in other manners, as long as it can achieve the effect of reflecting the propagation direction of the parallel light beam reflected by the parabolic concave reflector into a direction parallel to the optical axis of the original divergent light beam. In other optional embodiments, the plane transmission oblique window 32 may be disposed at the light outlet of the plane reflector 33. The plane transmission oblique window is configured to form an angle of 5-8° with the parallel light beam, further reducing interference and other problems caused by reflection from the plane transmission window.

[0103] Furthermore, the plane reflector 33 is made of mirror steel, and the reflective surface 331 is coated with a metal reflective film. In this embodiment, the plane reflector is manufactured using the same process as the rotational parabolic concave reflector. Both are made of the same material and have the same thermal expansion coefficient, so the mechanical structure is stable and the optical properties are not affected by temperature.

[0104] The collimation method of the lensless shaping device based on the parabolic concave reflector and the 45° plane reflector in Example 6 when used for light beam collimation includes the following steps:

[0105] S1: setting the light source exit point of the divergent light beam to be collimated and shaped at the focus of the rotating parabolic concave reflector;

[0106] S2: adjusting the angle between the center line of the divergent beam of the divergent beam light source and the main axis of the rotating parabolic concave reflector so that the off-axis angle between the center line of the divergent beam emitted by the divergent beam light source and the parallel beam reflected by the rotating parabolic concave reflector is less than 90°;

[0107] S3: The divergent beam light source emits a divergent beam and is incident on a rotating parabolic concave reflector. The divergent beam is reflected by the rotating parabolic concave reflector to form a parallel beam, which is then reflected by a plane reflector and then formed into a collimated beam parallel to the optical axis of the divergent beam.

[0108] Example 7 Application of lensless beam collimation based on a rotating parabolic concave reflector and a 45° plane reflector in a laser sensor in which the collimated laser beam is parallel to the optical axis of the original divergent beam

[0109] As shown in Figures 1-2, 5-6, 8, and 10, this embodiment 2 is the application of the above-mentioned embodiment 6 in a laser sensor 20 in which the collimated laser beam is parallel to the optical axis of the original divergent beam;

[0110] Specifically, the laser sensor 20 also includes a packaging device 201 and a laser chip 202 and a heat sink 203 disposed in the packaging device 201; the beam shaping device 10 is adapted to be installed between the laser chip 201 and the light outlet 204 of the packaging device; the vertical distance from the bottom surface of the base 4 to the focus F of the rotating parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink 203 to the laser beam exit point of the laser chip 201; the plane reflector 33 is disposed at the parallel light beam exit point of the rotating parabolic concave reflector 31. In other optional embodiments, the plane transmission oblique window 32 is disposed at the light outlet point of the plane reflector 33, which is disposed corresponding to the light outlet 204 of the packaging device;

[0111] In this embodiment, the vertical distance from the bottom surface of the base to the focal point of the parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink to the laser beam exit point of the laser chip. This is intended to ensure that after the laser chip, heat sink, TEC and other optical components of the sensor are installed, the vertical distance from the bottom surface of the heat sink (or other components that can determine the position of the laser chip beam exit point, such as the inner bottom surface of the packaging device) to the laser beam exit point of the laser chip is determined. The vertical distance from the bottom surface of the base to the focal point of the parabolic concave reflector can then be designed as needed. As long as the above two distances are ensured to be equal, the beam shaping device of the present invention can be quickly installed, and the exit point of the divergent beam light source can be simultaneously ensured to be located at the focal point of the parabolic concave reflector. This reduces the error in lens installation in the prior art and greatly reduces the installation difficulty and manufacturing cost of the collimation system.

[0112] The laser divergent beam emitted by the laser chip is reflected by the rotating parabolic concave reflector, and then reflected by the plane reflector to form a collimated beam parallel to the optical axis of the original divergent beam, which is emitted from the plane transmission oblique window and the light outlet.

[0113] Since the collimated laser beam is parallel to the optical axis of the original divergent beam, this laser packaging structure can be used in sensor applications to directly replace the existing lens collimated laser, avoiding reflection interference caused by the lens.

[0114] Example 8 Lensless beam convergence based on a rotating parabolic concave reflector and a 45° plane reflector

[0115] As shown in Figures 1-2, 5, 7, 9, and 11, this embodiment 8 provides a lensless beam shaping device based on a combination of a rotating parabolic concave reflector and a 45° plane reflector, which is used to converge parallel light beams. The difference between this embodiment 8 and embodiment 6 is that:

[0116] (1) The optical path of the eighth embodiment is opposite to that of the sixth embodiment. The eighth embodiment receives parallel light beams for convergence.

[0117] (2) The light source of this embodiment 8 is a parallel beam light source 2 that can emit parallel beams, and a convergence point 21 (such as a detector photosensitive surface) of the parallel beam to be converged and shaped is set at the focus F of the rotating parabolic concave reflector;

[0118] (3) The beam converging and shaping method of this embodiment 8 is different and includes the following steps:

[0119] S1: setting the convergence point of the parallel light beam to be converged and shaped emitted by the parallel light beam light source at the focus of the rotating parabolic concave reflector;

[0120] S2: Adjusting the parallel light beam to be parallel to the principal axis of the rotating parabolic concave reflector so that the off-axis angle between the center line of the convergent light beam emitted by the parallel light beam light source and the original incident parallel light beam after being reflected by the rotating parabolic concave reflector is less than or equal to 90°;

[0121] S3: The parallel light beam emitted by the parallel light beam light source is incident, reflected by the plane reflector, and then reflected by the rotating parabolic concave reflector and converged to the convergence point.

[0122] Furthermore, in S2, an off-axis angle α between a center line of the convergent beam of the parallel light beam emitted by the parallel light beam light source 2 after being reflected by the rotating parabolic concave reflector and a center line of the parallel light beam after being reflected by the plane reflector is 80-90°.

[0123] Example 9 Application of lensless beam convergence based on rotating parabolic concave reflector and 45° plane reflector in detector

[0124] As shown in Figures 1-2, 5, 7, 9, and 11, this embodiment 9 provides an application of a lensless beam converging device based on a rotating parabolic concave reflector and a 45° plane reflector in a detector 30;

[0125] Specifically, the detector photosensitive surface 301 is set at the focus F of the rotating parabolic concave reflector 31; the plane reflector 33 is set at the place where the parallel light beam enters the rotating parabolic concave reflector 31; after the parallel light beam is incident, it is reflected by the plane reflector and then reflected by the rotating parabolic concave reflector and converges onto the detector photosensitive surface.

[0126] The light beam converging process of this embodiment refers to Example 8.

[0127] The above-mentioned embodiments 1-9 are preferred implementations of the present invention. In addition to the above-mentioned embodiments, the beam shaping device of the present invention can also be adaptively adjusted and applied according to different packaging methods of products such as lasers and detectors. As long as the present invention meets the following requirements, a rotating parabolic concave reflector is provided on a base, and is matched with a plane transmission oblique window and / or a 45° plane reflector, and an adjustable angle between the center line of the divergent beam of the divergent beam light source and the main axis of the rotating parabolic concave reflector is adjusted so that the off-axis angle between the center line of the divergent beam emitted by the divergent beam light source and the parallel beam after being reflected by the rotating parabolic concave reflector is less than or equal to 90°; The divergent light beam is collimated and shaped to form a collimated light beam that is perpendicular or parallel to the optical axis of the divergent light beam; and according to the principle of reversible light path, the present invention can also converge and shape the received parallel light beam, that is, the collimating lens or the converging lens of the detector in the prior art can be directly replaced by a simple structure. In the process of collimating or converging the light beam, the interference noise caused by the reflection of the optical element surface due to the use of the collimating lens or the converging lens is directly avoided, thereby greatly improving the measurement accuracy. At the same time, a series of alignment operations to ensure accuracy during the installation of the collimating lens are avoided, greatly reducing the difficulty of installation.

[0128] The beam shaping device of the present invention has a wide range of applications and is not limited by the wavelength of the light beam. The same reflective collimation system can be used for laser light sources of different wavelengths. Therefore, the present invention can be used to collimate different laser wavelengths, thereby realizing different gas detection. In addition, because the mirror surfaces of the rotating parabolic concave reflector and the plane reflector absorb very little light beam energy, the beam shaping device of the present invention can also be used in the collimation of high-power or even ultra-high-power lasers.

[0129] On the other hand, the present invention is extremely convenient to install. Taking the application of a laser sensor as an example, after the laser chip, heat sink, TEC and other optical components of the sensor are installed, the vertical distance from the bottom surface of the heat sink (or other components that can determine the position of the laser chip beam exit point, such as the inner bottom surface of the packaging device) to the laser beam exit point of the laser chip is determined. The vertical distance from the bottom surface of the base to the focus of the rotating parabolic concave reflector can be designed as needed. As long as the above two distances are ensured to be equal, the beam shaping device of the present invention can be quickly installed, and the exit point of the divergent beam light source can be simultaneously ensured to be located at the focus of the rotating parabolic concave reflector. This reduces the error of lens installation in the prior art and greatly reduces the installation difficulty and manufacturing cost of the collimation system.

[0130] Similarly, when the present invention is applied to a detector, the photosensitive surface of the detector and the focus of the rotating parabolic concave reflector can be quickly aligned, thereby quickly completing the installation of the beam converging and shaping device.

[0131] Another outstanding advantage of the lensless beam shaping device of the present invention is that the size of the laser spot in the fast axis direction can be adjusted: since the rotating parabolic concave reflector of the present invention is a semicircular parabolic mirror formed by rotating the parabola 180 degrees around the main axis with the main axis of the parabola as the central axis, the fast axis of the divergent beam light source is set to be parallel to the main axis of the parabolic mirror, and the off-axis angle between the center line of the divergent beam (light cone) emitted by the divergent beam light source and the parallel beam after reflection by the rotating parabolic concave reflector is slightly less than 90°. This setting is because for light cones with the same divergence angle, if the angle (off-axis angle) between the center axis of the light cone and the parallel beam after reflection is equal to or smaller than 90°, the off-axis angle between the center axis of the light cone and the parallel beam after reflection is equal to or smaller than 90°. When the off-axis angle is different (i.e., the angle of the beam is not equal to the beam width), the diameter of the reflected light spot formed when it is reflected by the rotating parabolic concave reflector is different. When the off-axis angle is gradually reduced from 90°, the diameter of the reflected light spot also gradually decreases. By utilizing the physical property of the rotating parabolic concave reflector, the center line of the laser's light cone and the collimated light beam are adjusted to form an angle less than 90°, thereby reducing the diameter of the light spot in the fast axis direction, thereby collimating the divergent light beam with an elliptical cross-section into a parallel light beam with an approximately circular cross-section. Then, a 45° plane reflector is used to reflect the parallel light beam to the coaxial direction of the laser, facilitating the installation and adjustment of the laser. That is, the present invention can simultaneously achieve the functions of beam collimation and light spot size adjustment.

[0132] It should also be noted that the collimated laser and detector involved in the present invention also include other optical elements or electrical elements that meet the normal operation of the collimated laser and detector, which are not described here one by one.

[0133] The above embodiments are only preferred embodiments of the present invention and cannot be used to limit the scope of protection of the present invention. For ordinary technicians in this field, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the attached claims and their equivalents.

Claims

1. A lensless beam shaping device based on a parabolic concave reflector, used for collimating a divergent beam or converging a parallel beam; characterized in that: It comprises a divergent beam light source or a parallel beam light source, a beam shaping component for adjusting the direction of the beam light path, and a base for installing the beam shaping component; the beam shaping component comprises a rotational parabolic concave reflector, and the rotational parabolic concave reflector is concavely arranged on the base; the emission point of the divergent beam light source or the convergence point of the parallel beam emitted by the parallel beam light source is located at the focus of the rotational parabolic concave reflector; the off-axis angle between the center line of the divergent beam emitted by the divergent beam light source and the parallel beam reflected by the rotational parabolic concave reflector is less than or equal to 90°; The beam shaping assembly further comprises a plane transmission oblique window and / or a plane reflector arranged on the base; the plane transmission oblique window and / or the plane reflector are located on the reflection optical path of the light beam; the angle between the reflection surface of the plane reflector and the incident center line of the divergent light beam or the parallel light beam is 45°; an angle is formed between the plane transmission oblique window and the parallel light beam; The divergent light beam emitted by the divergent light beam source can be reflected by the rotating parabolic concave reflector to form a parallel light beam that can be emitted from the plane transmission oblique window, or it can be reflected by the plane reflector to form a collimated light beam that is parallel to the optical axis of the divergent light beam. Or according to the reversible principle of optical path, the parallel light beam emitted by the parallel light beam light source is incident and then reflected by the plane transmission oblique window or by the plane reflector and then converged to the convergence point by the rotating parabolic concave reflector.

2. The lensless beam shaping device based on a parabolic concave reflector according to claim 1, characterized in that: The base is a rectangular parallelepiped base; the rotating parabolic concave reflector is a concave rotating reflector that is rotated 180 degrees about the central axis of the parabola and is integrally formed on the rectangular parallelepiped base.

3. The lensless beam shaping device based on a parabolic concave reflector according to claim 1 or 2, characterized in that: The off-axis angle between the center line of the divergent beam emitted by the divergent beam light source and the parallel beam reflected by the rotating parabolic concave reflector is 80-90°; the fast axis of the divergent beam light source is parallel to the main axis of the rotating parabolic concave reflector.

4. A beam shaping method of a lensless beam shaping device based on a parabolic concave reflector according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1: setting the light source exit point of the divergent light beam to be collimated and shaped at the focus of the rotating parabolic concave reflector; S2: adjusting the angle of the divergent light beam center line of the divergent light beam exit point relative to the main axis of the rotating parabolic concave reflector, so that the off-axis angle between the center line of the divergent light beam emitted by the divergent light beam source and the parallel light beam reflected by the rotating parabolic concave reflector is less than or equal to 90°; S3: The divergent beam light source emits a divergent beam and is incident on a rotating parabolic concave reflector. The divergent beam is reflected by the rotating parabolic concave reflector to form a parallel beam that can be emitted from the plane transmission oblique window, or it is reflected by a 45-degree plane reflector to form a collimated beam that is parallel to the optical axis of the divergent beam, and then emitted from the plane transmission oblique window.

5. A beam shaping method of a lensless beam shaping device based on a parabolic concave reflector according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1: setting the convergence point of the parallel light beam to be converged and shaped emitted by the light source at the focus of the rotating parabolic concave reflector; S2: Adjust the parallel light beam to be parallel to the main axis of the rotating parabolic concave reflector, so that the off-axis angle between the center line of the convergent light beam emitted by the parallel light beam light source and the center line of the original incident parallel light beam after being reflected by the rotating parabolic concave reflector is less than or equal to 90°; S3: A light beam parallel to the main axis of the rotating parabolic concave reflector emitted by a parallel light beam source passes through the plane transmission oblique window or is reflected by the plane reflector again, and then is reflected by the rotating parabolic concave reflector and converges to the focus of the concave reflector.

6. An application of the lensless beam shaping device based on a parabolic concave reflector as claimed in any one of claims 1 to 3 in a laser sensor in which the collimated laser beam is parallel to the optical axis of the original divergent beam, characterized in that: The laser sensor further comprises a packaging device and a laser chip and a heat sink arranged in the packaging device; the beam shaping device is adapted to be installed between the laser chip and the light outlet of the packaging device; the vertical distance from the bottom surface of the base to the focus of the rotating parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink to the laser beam exit point of the laser chip; the plane reflector is arranged at the parallel beam exit of the rotating parabolic concave reflector, and the plane transmission oblique window is arranged corresponding to the light outlet of the packaging device; The laser divergent beam emitted by the laser chip is reflected by the rotating parabolic concave reflector, and then reflected by the plane reflector to form a collimated beam parallel to the optical axis of the original divergent beam, which is emitted from the plane transmission oblique window and the light outlet.

7. An application of the lensless beam shaping device based on a parabolic concave reflector as claimed in any one of claims 1 to 3 in a laser sensor in which the collimated laser beam is perpendicular to the optical axis of the original divergent beam, characterized in that: The laser sensor also includes a packaging device and a laser chip and a heat sink arranged in the packaging device; the beam shaping device is adapted to be installed between the laser chip and the light outlet of the packaging device; the vertical distance from the bottom surface of the base to the focus of the rotating parabolic concave reflector is the same as the vertical distance from the bottom surface of the heat sink to the laser beam exit point of the laser chip; the plane transmission oblique window is arranged at the parallel beam exit of the rotating parabolic concave reflector; The laser divergent beam emitted by the laser chip is reflected by the rotary parabolic concave reflector to form a collimated beam perpendicular to the optical axis of the original divergent beam, which is emitted from the plane transmission oblique window and the light outlet.

8. An application of the lensless beam shaping device based on a parabolic concave reflector as claimed in any one of claims 1 to 3 in a laser sensor in which the collimated laser beam is perpendicular to the optical axis of the original divergent beam, characterized in that: The laser sensor further comprises a packaging device and a laser chip and a heat sink arranged in the packaging device; the packaging device is a "right-angle TO-CAN packaging device", comprising a TO base for mounting the laser chip and the heat sink; the base is arranged on the TO base, the light outlet of the laser chip is arranged at the focus of the rotating parabolic concave reflector, the center line of the divergent light beam emitted from the laser chip is perpendicular to the optical axis of the rotating parabolic concave reflector, the plane transmission oblique window is arranged at the parallel light beam outlet of the rotating parabolic concave reflector, and corresponds to the light outlet of the right-angle TO-CAN packaging device; The divergent laser beam emitted by the laser chip is reflected by the rotating parabolic concave reflector to form a collimated beam parallel to the right-angle TO base, which is emitted from the plane transmission oblique window and the light outlet.

9. An application of the lensless beam shaping device based on a parabolic concave reflector as claimed in any one of claims 1 to 3 in a detector that receives parallel beams and performs convergence shaping, characterized in that: The detector photosensitive surface is arranged at the focus of the rotating parabolic concave reflector; the plane reflector is arranged at the place where the parallel light beam of the rotating parabolic concave reflector enters; the parallel light beam parallel to the main axis of the rotating parabolic concave reflector is incident, reflected by the plane reflector, and then reflected by the rotating parabolic concave reflector and converged onto the detector photosensitive surface.

10. An application of the lensless beam shaping device based on a parabolic concave reflector as claimed in any one of claims 1 to 3 in a detector that receives parallel beams and performs convergence shaping, characterized in that: The detector includes a TO-CAN packaging device; the TO-CAN packaging device includes a TO base, the base is arranged on the TO base, the detector photosensitive surface is arranged at the focus of the rotating parabolic concave reflector, the plane transmission oblique window is arranged at the entrance of the parallel light beam of the rotating parabolic concave reflector, and corresponds to the light inlet of the TO-CAN packaging device; after the parallel light beam is incident, it passes through the plane transmission oblique window and then is reflected by the rotating parabolic concave reflector and converges onto the detector photosensitive surface.

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