Optical device for generating linear light spots

Abstract

The utility model provides an optical device for generating a linear light spot. The optical device comprises a first super lens; a horizontal cavity surface emitting laser HCSEL light source; the first super lens comprises a first substrate and a first micro-nano structure arranged on the first substrate; the first super lens is used for expanding a light beam received by the first super lens in the line length direction of the linear light spot so as to modulate the light beam into a linear light beam, and the linear light beam is used for forming the linear light spot on a target plane. According to the optical device, generation of a linear light spot or a linear light spot array can be achieved through the super lens, and the production cost and the size of the optical device are reduced.

Description

Technical Field

[0001] This application relates to the field of optics, and particularly to an optical device for generating a linear light spot. Background Art

[0002] In application fields such as intelligent detection, laser ablation, and three-dimensional scanning, it is necessary to make the light intensity of the laser emitted by a laser emitter be distributed as required, so as to generate a corresponding linear light spot or a linear light spot array, and be used in related applications.

[0003] In conventional linear light spot design solutions, an edge-emitting laser (EEL) or a vertical-cavity surface-emitting laser (VCSEL) is usually selected as the light source, and at the same time, a lens with a collimation function (such as a spherical mirror or a cylindrical mirror) and an optical element with a beam expansion function (such as a diffractive optical element, a Powell prism, or a cylindrical mirror) are respectively arranged on the light beam propagation path, so as to generate a linear light spot on a target plane; or while arranging an optical element with a collimation function and an optical element with a beam expansion function, an optical element with a beam splitting function is further arranged, so as to generate a linear light spot array on the target plane. However, the above solutions require multiple optical elements, which is not conducive to the miniaturization of the entire optical device and has a high production cost. Summary of the Utility Model

[0004] An object of this application is to provide an optical device for generating a linear light spot. The optical device for generating a linear light spot provided by this application can generate a linear light spot or a linear light spot array through a metalens, making the optical device have high integration, a small volume, and a low production cost.

[0005] According to one aspect of the embodiments of this application, an optical device for generating a linear light spot is disclosed. The optical device includes: a first metalens; a horizontal-cavity surface-emitting laser (HCSEL) light source; the first metalens includes a first substrate and a first micro-nano structure disposed on the first substrate;

[0006] The first metalens is configured to expand the received light beam in the line length direction of the linear light spot, so as to modulate the light beam into a linear light beam, and the linear light beam is used to form a linear light spot on a target plane.

[0007] In an exemplary embodiment of this application, the first metalens is disposed on the light-emitting side of the light-emitting area of the HCSEL light source;

[0008] The fast axis direction of the HCSEL light source is parallel to the line length direction of the one-dimensional line spot, and the slow axis direction of the HCSEL light source is parallel to the line width direction of the one-dimensional line spot.

[0009] In an exemplary embodiment of the present application, the HCSEL light source includes a plurality of light-emitting regions, and each of the light-emitting regions is arranged in an array along the line length direction of the one-dimensional line spot;

[0010] The effective area of the first metalens includes a plurality of partitions, the number of partitions is equal to the number of the light-emitting regions, and the partitions are in one-to-one correspondence with the light-emitting regions;

[0011] Each of the partitions is respectively configured to receive the light beam emitted by the corresponding light-emitting region, and respectively expand the corresponding light beam in the line length direction of the one-dimensional line spot and deflect it in the line width direction.

[0012] In an exemplary embodiment of the present application, the boundary line between adjacent partitions on the first metalens is parallel to the line width direction of the one-dimensional line spot, and the boundary line between adjacent partitions is perpendicular to the line length direction of the one-dimensional line spot.

[0013] In an exemplary embodiment of the present application, each partition on the first metalens is further configured to compress the light beam received thereon in the line width direction of the one-dimensional line spot.

[0014] In an exemplary embodiment of the present application, each partition on the first metalens is further configured to collimate the light beam received thereon in the line length direction of the one-dimensional line spot.

[0015] In an exemplary embodiment of the present application, the first metalens is disposed on the light-emitting side of the light-emitting region of the HCSEL;

[0016] The fast axis direction of the HCSEL light source is parallel to the line width direction of the one-dimensional line spot, and the slow axis direction of the HCSEL light source is parallel to the line length direction of the one-dimensional line spot.

[0017] In an exemplary embodiment of the present application, the first metalens is disposed on the light-emitting side of the light-emitting region of the HCSEL light source, including:

[0018] The first metalens is disposed outside the HCSEL light source; or,

[0019] The first metalens is integrated inside the HCSEL light source.

[0020] In an exemplary embodiment of the present application, when the first metalens is integrated inside the HCSEL light source, the optical device further includes: a focusing lens;

[0021] The focusing lens is disposed on the light-emitting side of the HCSEL light source, and the focusing lens is configured to compress the received light beam in the line width direction of the one-dimensional line spot;

[0022] Wherein, the focusing lens is a cylindrical lens or a second superlens.

[0023] In an exemplary embodiment of the present application, when the focusing lens is a second superlens, the second superlens is further configured to deflect the received light beam in the line width direction of the one-dimensional line spot to form an eccentric one-dimensional line spot.

[0024] The optical device for generating a one-dimensional line spot provided by the present application includes: a first superlens; a horizontal cavity surface emitting laser (HCSEL) light source; the first superlens includes a first substrate and a first micro-nano structure disposed on the first substrate; the first superlens is configured to expand the received light beam in the line length direction of the one-dimensional line spot to modulate the light beam into a one-dimensional line beam, and the one-dimensional line beam is configured to form a one-dimensional line spot on a target plane. The present application can generate a one-dimensional line spot or an array of one-dimensional line spots through a superlens, reducing the production cost and volume of the optical device.

[0025] Other features and advantages of the present application will become apparent from the following detailed description, or will be learned in part through the practice of the present application.

[0026] It should be understood that the above general description and the following detailed description are exemplary only and do not limit the present application. Description of the Drawings

[0027] By referring to the accompanying drawings and describing its exemplary embodiments in detail, the above and other objects, features, and advantages of the present application will become more apparent.

[0028] Figure 1 The schematic structural diagram of the first superlens provided by an embodiment of the present application is shown.

[0029] Figure 2 The schematic diagram of the HCSEL light source including a plurality of light-emitting regions provided by an embodiment of the present application is shown.

[0030] Figure 3 The schematic diagram of the first superlens provided by an embodiment of the present application is shown.

[0031] Figure 4 The schematic diagram of the optical device provided by an embodiment of the present application is shown.

[0032] Figure 5 The schematic diagram of the optical device provided by an embodiment of the present application is shown.

[0033] Figure 6 Shows a schematic structural diagram of an HCSEL light source integrated with a superlens provided by an embodiment of the present application.

[0034] Figure 7 Shows a schematic diagram of an optical device provided by an embodiment of the present application.

[0035] Figure 8 Shows a partial schematic structural diagram of an HCSEL light source integrated with a superlens provided by an embodiment of the present application.

[0036] Figure 9 Shows a partial schematic structural diagram of an HCSEL light source integrated with a superlens provided by an embodiment of the present application.

[0037] Figure 10 Shows a partial schematic structural diagram of an HCSEL light source integrated with a superlens provided by an embodiment of the present application.

[0038] Figure 11 Shows a partial schematic structural diagram of an HCSEL light source integrated with a superlens provided by an embodiment of the present application.

[0039] Figure 12 Shows a schematic diagram of an optical device provided by an embodiment of the present application.

[0040] Figure 13 Shows a schematic diagram of the light intensity distribution of a one-dimensional line spot projected by the optical device provided by Embodiment 1 of the present application.

[0041] Figure 14 Shows a schematic diagram of the light intensity distribution of an eccentric one-dimensional line spot projected by the optical device provided by Embodiment 1 of the present application.

[0042] Figure 15 Shows a schematic diagram of an array of one-dimensional line spots projected by the optical device provided by Embodiment 2 of the present application.

[0043] Figure 16 Shows a schematic diagram of an array of one-dimensional line spots projected by the optical device provided by Embodiment 3 of the present application.

[0044] Figure 17 Shows a schematic diagram of an array of one-dimensional line spots projected by the optical device provided by Embodiment 4 of the present application.

[0045] Reference numerals:

[0046] 1 - First superlens; 11 - First substrate; 12 - First micro-nano structure; 110 - First partition;

[0047] 120 - Second partition; 130 - Third partition; 2 - HCSEL light source; 21 - N electrode;

[0048] 22 - Substrate; 23 - Excitation region; 24 - Grating; 25 - P electrode; 210 - First light-emitting region;

[0049] 220 - Second light-emitting region; 230 - Third light-emitting region; 3 - Target plane; 4 - Crosshair light spot; 5 - Focusing lens. Detailed implementation mode

[0050] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these example embodiments are provided so that this application will be more thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The drawings are only schematic illustrations of this application and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and thus repeated descriptions thereof will be omitted.

[0051] In addition, the described features, structures, or characteristics can be combined in any suitable manner in one or more example embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the example embodiments of this application. However, those skilled in the art will realize that one or more of the specific details can be omitted in practicing the technical solutions of this application, or other methods, components, steps, etc. can be adopted. In other cases, well-known structures, methods, implementations, or operations are not shown or described in detail to avoid obscuring the various aspects of this application.

[0052] In the prior art, an EEL or VCSEL is usually used as the light source of an optical device for generating a crosshair light spot, and then an optical element with a collimation function and an optical element with a beam expansion function are respectively arranged on the propagation path of the light beam, so as to form a crosshair light spot on the target plane; or on the basis of the above solution, an optical element with a beam splitting function is further arranged, so as to form a crosshair light spot array on the target plane. However, the above solutions require multiple different optical elements to achieve the projection of a crosshair light spot or a crosshair light spot array, making it difficult to miniaturize the optical device and resulting in a relatively high production cost.

[0053] In consideration of overcoming the above-mentioned defects existing in the related art, this application provides an optical device for generating a crosshair light spot. Through the optical device provided by this application, the projection of a crosshair light spot or a crosshair light spot array can be achieved through a meta-lens, reducing the volume of the optical device where it is located and also reducing the production cost.

[0054] The present application provides an optical device for generating a one-dimensional line spot. This optical device includes: a first metalens 1; a horizontal cavity surface emitting laser (HCSEL) light source 2. As Figure 1 shown, Figure 1 FIG. 4 shows a schematic structural diagram of the first metalens 1 provided by an embodiment of the present application. The first metalens 1 includes a first substrate 11 and a first micro-nano structure 12 disposed on the first substrate 11. The first micro-nano structure 12 is a sub-wavelength structure. The first metalens 1 mainly provides corresponding phases at various positions thereon by configuring parameters such as the material, cross-sectional size, height, and arrangement period of the first micro-nano structure 12 at various positions thereon, applies a phase mutation to the received light beam, and further enables each position on the first metalens 1 to have a certain phase gradient, so that the first metalens 1 modulates the light beams received at different positions thereon. The first metalens 1 is used to expand the light beam received thereon in the line length direction of the one-dimensional line spot to modulate the received light beam into a one-dimensional line beam, and the one-dimensional line beam is used to form a one-dimensional line spot on the target plane.

[0055] It should be noted that, compared with a VCSEL light source, the light beam emitted by the HCSEL light source 2 has a smaller divergence angle in the slow axis direction and a larger divergence angle in the fast axis direction. The spectral line width of the HCSEL light source 2 is narrow and the wavelength is stable, which is more convenient for three-dimensional scanning and lidar applications; compared with an EEL light source, the HCSEL light source 2 is a surface emitting laser, and the EEL light source is an edge emitting laser. The HCSEL light source 2 has a higher output power and a simpler manufacturing process.

[0056] In an embodiment of the present application, the first metalens 1 is disposed on the light output side of the light emitting region of the HCSEL light source 2. In this case, the fast axis direction of the HCSEL light source 2 is parallel to the line length direction of the one-dimensional line spot, and the slow axis direction of the HCSEL light source 2 is parallel to the line width direction of the one-dimensional line spot. That is to say, actually in this embodiment, the first metalens 1 expands the light beam received thereon in the fast axis direction of the HCSEL light source 2.

[0057] It should be noted that, in the embodiment of the present application, the first metalens 1 is disposed on the light output side of the light emitting region of the HCSEL light source 2, including but not limited to the following two cases: one is to integrate the first metalens 1 inside the HCSEL light source 2, and the other is to dispose the first metalens 1 outside the HCSEL light source 2.

[0058] c In an embodiment, the HCSEL light source 2 includes a plurality of light emitting regions, as Figure 2 shown, Figure 2 FIG. 20 shows a schematic diagram of the HCSEL light source 2 including a plurality of light emitting regions provided by an embodiment of the present application. In Figure 2In [the figure], the HCSEL light source 2 includes three light-emitting regions, namely a first light-emitting region 210, a second light-emitting region 220, and a third light-emitting region 230. Among them, the spacing between each light-emitting region is equal, and each light-emitting region is arranged in an array along the line length direction of the one-dimensional line-shaped light spot. As Figure 4 shown, Figure 4 shows a schematic diagram of an optical device provided by an embodiment of the present application. In Figure 4 it, each light-emitting region in the HCSEL light source 2 is arranged in an array along the line length direction of the one-dimensional line-shaped light spot 4, and the fast axis direction of each light-emitting region is parallel to the line length direction of the one-dimensional line-shaped light spot 4. Among them, the short side direction of the light source of each light-emitting region is the fast axis direction of each light-emitting region. That is to say, each light-emitting region in the HCSEL light source 2 is actually arranged in an array along the fast axis direction.

[0059] In this case, the first superlens 1 also includes multiple partitions. As Figure 3 shown, Figure 3 shows a schematic diagram of the first superlens provided by an embodiment of the present application. In Figure 3 it, the first superlens 1 includes three partitions, namely a first partition 110, a second partition 120, and a third partition 130.

[0060] Specifically, the number of partitions of the first superlens 1 is equal to the number of light-emitting regions of the HCSEL light source 2, and the partitions and the light-emitting regions are in one-to-one correspondence. Refer to Figure 2 and Figure 3 , the first partition 110 corresponds to the first light-emitting region 210, the second partition 120 corresponds to the second light-emitting region 220, and the third partition 130 corresponds to the third light-emitting region 230. Each partition is respectively used to receive the light beam emitted by the corresponding light-emitting region, respectively expand the corresponding light beam in the line length direction of the one-dimensional line-shaped light spot 4, and deflect it along the line width direction to output the one-dimensional line-shaped light beam corresponding to each partition, and multiple one-dimensional line-shaped light beams form multiple one-dimensional line-shaped light spots 4 on the target plane. Figure 3 The dotted line in [the figure] is the boundary line between adjacent partitions in the first superlens 1.

[0061] It should be emphasized that Figure 2 the number of light-emitting regions shown in [the figure] and Figure 3 the number of partitions shown in [the figure] are only examples, and do not represent the actual number of light-emitting regions in the HCSEL light source 2 provided by the present application, and the actual number of partitions of the first superlens 1. The specific number can be set according to the actual situation. For the convenience of description, the HCSEL light source 2 shown in Figure 2 and Figure 3 the first superlens 1 shown in [the figure] will be used for description below.

[0062] The phase provided by each partition in the first metalens 1 is independently designed, and each partition on the first metalens 1 provides an independent shaping phase. Each shaping phase is at least used to provide different phase mutations for the light beams emitted by the corresponding light-emitting regions received by the corresponding partitions in the line length direction of the one-dimensional light spot 4, so that each partition can independently expand the light beams emitted by the corresponding light-emitting regions in the line length direction.

[0063] As Figure 4 shown, the first partition 110 provides a shaping phase for the first light-emitting region 210, the second partition 120 provides a shaping phase for the second light-emitting region 220, and the third partition 130 provides a shaping phase for the third light-emitting region 230.

[0064] Furthermore, since the first metalens 1 contains multiple partitions and each partition can independently modulate the received light beam, therefore, in order to form a one-dimensional light spot array on the target plane, the phase distribution of each partition in the first metalens 1 can further include a deflection phase; the deflection phase is used to deflect the light beam received by the partition in the line width direction of the one-dimensional light spot 4 to form a one-dimensional light beam with an exit angle, so that the one-dimensional light beams corresponding to each partition can finally form multiple non-overlapping one-dimensional light spots 4 on the target plane. It should be noted that the deflection phase corresponding to each partition can be designed according to the actual required deflection angle, so as to generate a one-dimensional light spot 4 array that more meets the design requirements.

[0065] As Figure 4 shown, in Figure 4 , the first partition 110 of the first metalens 1 projects a downward-eccentric one-dimensional light beam, the second partition 120 projects a directly-emitted one-dimensional light beam, and the third partition 130 projects an upward-eccentric one-dimensional light beam. The one-dimensional light spot array finally formed on the target plane also includes three one-dimensional light spots 4. That is, in this embodiment, actually only the phase distributions of the first partition 110 and the third partition 130 include the deflection phase.

[0066] c In one embodiment, the dividing line between adjacent partitions on the first metalens 1 is parallel to the line length direction of the one-dimensional light spot 4, and the dividing line between adjacent partitions is perpendicular to the line width direction of the one-dimensional light spot 4. Refer to Figure 4 . The dotted line between the first partition 110 and the second partition 120 is the dividing line, and the dotted line between the second partition 120 and the third partition 130 is also the dividing line; since on the first metalens 1, the dividing lines between adjacent partitions are all parallel to the line width direction of the one-dimensional light spot 4 and perpendicular to the line length direction of the one-dimensional light spot 4, therefore, the dividing line between the first partition 110 and the second partition 120 is parallel to the dividing line between the second partition 120 and the third partition 130.

[0067] It should be noted that, in order to prevent crosstalk from occurring to the light beams emitted by each light-emitting region in the HCSEL light source 2 before they irradiate the corresponding partition in the first superlens 1, that is, the light intensities of each light-emitting region irradiating the first superlens 1 do not overlap, in all embodiments where the HCSEL light source 2 includes multiple light-emitting regions, the distance from the HCSEL light source 2 to the first superlens 1 needs to be strictly controlled. As Figure 5 shown Figure 5 shows a schematic diagram of an optical device provided by an embodiment of the present application Figure 5 The angle is perpendicular to the fast axis direction of each light-emitting region and parallel to the slow axis direction of each light-emitting region. In Figure 5 , the spacing between the light-emitting areas of adjacent light-emitting regions is equal. If 1.5 times the width of the light spot irradiating the first superlens 1 in the fast axis direction of the light-emitting region (calculated at the e2 intensity of the peak) is taken as the cut-off of the light spot, the distance from the HCSEL light source 2 to the first superlens 1 needs to satisfy:

[0068]

[0069] wherein, L is the distance from the HCSEL light source 2 to the first superlens 1, d is the spacing between the light-emitting areas of adjacent light-emitting regions, and α is the divergence angle of the light beam emitted by the light-emitting region. Among them, the divergence angles of the light beams emitted by each light-emitting region of the HCSEL light source 2 are the same.

[0070] In one embodiment, the light beam received by each partition in the first superlens 1 is an uncollimated light beam. For an uncollimated light beam, although the divergence angle of the light beam emitted by the HCSEL light source 2 in the slow axis direction (the line width direction of the one-dimensional line light spot 4) is small, because the slow axis size of the HCSEL light source 2 is long, this results in that even though the divergence angle of the light beam in the slow axis direction is small, after propagating a certain distance, the line width of the formed one-dimensional line light spot 4 is large, and it is difficult to meet the design requirements (for example, the line width of the one-dimensional line light spot 4 is less than 3 mm). Therefore, the phase distribution of each partition of the first superlens 1 includes: a focusing phase for compressing the light beam in the line width direction of the one-dimensional line light spot 4 (the slow axis direction of the light-emitting region), so as to achieve the compression of the light beam received by each partition in the line width direction of the one-dimensional line light spot 4. In this case, the focusing phase of each partition in the first superlens 1 satisfies any one of the following:

[0071]

[0072] wherein, is the focusing phase of each partition in the first superlens 1, f1 is the effective focal length of the first superlens 1, k is the wave number of the working center wavelength of the first superlens 1, y is the distance from the point on the first superlens 1 in the line width direction of the one-dimensional line light spot to the center point, N is the phase order, ai is the phase coefficient, is the phase constant. Each partition of the first metalens 1 provides a focusing phase for the received light beam in the line length direction of the one-dimensional line spot 4, and can control the line width of the one-dimensional line spot 4 projected by each partition of the first metalens 1 to maintain a certain size at a preset transmission distance or within a preset transmission distance range, so as to meet the design requirements.

[0073] It should be noted that, in fact, each partition on the first metalens 1 can also provide a focusing phase for compressing the light beam in the line length direction of the one-dimensional line spot 4 as a whole.

[0074] In an embodiment, if the requirement for the light energy utilization rate in the line length direction of the linear array spot is high in actual needs, the phase distribution of each partition of the first metalens 1 can also include a collimation phase for collimating the received light beam in the line length direction of the one-dimensional line spot 4, thereby improving the edge steepness of the edge region of the one-dimensional line spot 4 projected by each partition of the first metalens 1 in the line length direction and effectively improving the light energy utilization rate.

[0075] In another embodiment of the present application, the first metalens 1 is disposed on the light-emitting side of the light-emitting region of the HCSEL light source 2. In this case, the slow axis direction of the HCSEL light source 2 is parallel to the line length direction of the one-dimensional line spot, and the fast axis direction of the HCSEL light source 2 is parallel to the line width direction of the one-dimensional line spot. That is to say, in fact, in this embodiment, the first metalens 1 expands the received light beam in the slow axis direction of the HCSEL light source 2.

[0076] It should be noted that, in the embodiments of the present application, the first metalens 1 is disposed on the light-emitting side of the light-emitting region of the HCSEL light source 2, including but not limited to the following two cases: one is integrating the first metalens 1 inside the HCSEL light source 2, and the other is disposing the first metalens 1 outside the HCSEL light source 2.

[0077] In an embodiment, integrating the first metalens 1 inside the HCSEL light source 2 as Figure 6 shown, Figure 6 shows a schematic structural diagram of the HCSEL light source 2 with an integrated metalens provided in an embodiment of the present application.

[0078] It should be noted that, as Figure 6As shown, the HCSEL light source 2 further includes an N electrode 21, a substrate 22, an excitation region 23, a grating 24, and a P electrode 25. The shapes and sizes of each layer are adapted to each other and stacked with the first superlens 1 to form an integral structure. Among them, the grating 24 is located on the horizontal cavity surface or inside the HCSEL light source 2 and is responsible for laser mode locking and coupling and outputting a beam. The beam modulated by the first superlens 1 is the beam coupled and output by the grating 24. Figure 6 The arrow in it is the light output direction.

[0079] In this embodiment, the first superlens 1 is integrated into the HCSEL light source 2, so that the beam vertically coupled out by the grating 24 is modulated, enabling the HCSEL light source 2 to output a beam with a specified divergence angle and a uniform light intensity distribution. There is no need to set a light source element with a light homogenization function on the propagation path of the beam after the HCSEL light source 2 emits the beam, reducing the volume of the optical device. At the same time, the HCSEL light source 2 and the first superlens 1 are fabricated integrally, reducing the complexity of processing and assembly and enhancing the anti-vibration ability of the optical device. Moreover, the HCSEL light source 2 integrated with the first superlens 1 conforms to the semiconductor processing technology, has a simpler processing procedure compared with the EEL light source, and has a higher power and a narrower spectrum compared with the VCSEL light source.

[0080] In another embodiment, in the HCSEL light source 2 integrated with the first superlens 1, when designing the phase of the first superlens 1, it can be designed specifically according to the requirements of the actual application scenario. For example, according to the requirements of a non-uniform one-dimensional line beam or an asymmetric one-dimensional line beam, the phase of the first superlens 1 is designed specifically, so that the light intensity distribution of the beam directly projected by the HCSEL light source 2 meets the design requirements. In this case, the HCSEL light source 2 can define the light intensity distribution of the beam it outputs, improving the flexibility of the beam output by the HCSEL light source 2.

[0081] In one embodiment, in order to enable the first superlens 1 to modulate the beam coupled and output by the grating 24, the first superlens 1 is arranged at the light output place. As Figure 6 shown, the first superlens 1 is arranged between the N electrode 21 and the substrate 22 in the HCSEL light source.

[0082] Further, since the light beam coupled and output by the grating 24 has a certain divergence angle after being modulated by the first metalens 1, considering the light blocking risk of the N electrode 21 at a large divergence angle, the first metalens 1 and the N electrode 21 can be arranged on the same plane, or the first metalens 1 and the N electrode 21 can be arranged on different planes, including but not limited to: along the light beam propagation direction, both the first substrate 11 and the first micro-nano structure 12 of the first metalens 1 are located upstream of the N electrode 21; the first substrate 11 is located upstream of the N electrode 21, and the first micro-nano structure 12 is on the same layer as the N electrode 21; both the first substrate 11 and the first micro-nano structure 12 are on the same layer as the N electrode 21; the first substrate 11 is on the same layer as the N electrode 21, and the first micro-nano structure 12 is located downstream of the N electrode 21.

[0083] See specifically Figures 8 to 11 , Figure 8 FIG. shows a partial structural schematic diagram of the HCSEL light source 2 integrated with the metalens 1 provided by an embodiment of the present application. In Figure 8 , the arrow is the light beam propagation direction, and both the first substrate 11 and the first micro-nano structure 12 are located upstream of the N electrode 21. Figure 9 FIG. shows a partial structural schematic diagram of the HCSEL light source 2 integrated with the metalens 1 provided by an embodiment of the present application. In Figure 9 , the arrow is the light beam propagation direction, the first substrate 11 is located upstream of the N electrode 21, and the first micro-nano structure 12 is arranged on the same layer as the N electrode 21. Figure 10 FIG. shows a partial structural schematic diagram of the HCSEL light source 2 integrated with the metalens 1 provided by an embodiment of the present application. In Figure 10 , the arrow is the light beam propagation direction, and both the first substrate 11 and the first micro-nano structure 12 are arranged on the same layer as the N electrode 21. Figure 11 FIG. shows a partial structural schematic diagram of the HCSEL light source 2 integrated with the metalens 1 provided by an embodiment of the present application. In Figure 11 , the arrow is the light beam propagation direction, the first substrate 11 is arranged on the same layer as the N electrode 21, and the first micro-nano structure 12 is arranged downstream of the N electrode 21.

[0084] In one embodiment, the slow axis direction of the HCSEL light source 2 is parallel to the line length direction of the one-dimensional line spot 4, the fast axis direction of the HCSEL light source 2 is parallel to the line width direction of the one-dimensional line spot, and the first metalens 1 is integrated inside the HCSEL light source 2. Specifically, in this case, as Figure 7 shown, Figure 7The figure shows a schematic diagram of an optical device provided by an embodiment of the present application. The fast axis direction of the HCSEL light source 2 is parallel to the line width direction of the one-dimensional line spot 4, and the slow axis direction of the HCSEL light source is parallel to the line length direction of the one-dimensional line spot 4. That is to say, actually, the first superlens 1 expands the light beam received by it in the slow axis direction of the HCSEL light source 2.

[0085] Furthermore, the phase of the first superlens 1 further includes a light homogenization phase, and the light homogenization phase is used to homogenize the light intensity distribution of the light beam received by the first superlens 1, so that the first superlens 1 can output a light beam with a uniform light intensity distribution. Considering that the light emitting area of the HCSEL light source 2 is generally a long rectangle, the light homogenization phase of the first superlens 1 is only used to homogenize the light intensity distribution of the light beam in the line length direction of the one-dimensional line spot, and does not modulate the light beam in the line width direction of the one-dimensional line spot, so that the HCSEL light source 2 can output a light beam with a divergence angle in the line length direction of the one-dimensional line spot and a uniform light intensity distribution.

[0086] In an embodiment, when the slow axis direction of the HCSEL light source 2 is parallel to the line length direction of the one-dimensional line spot, the fast axis direction of the HCSEL light source 2 is parallel to the line width direction of the one-dimensional line spot, and the first superlens 1 is integrated inside the HCSEL light source 2, the optical device further includes: a focusing lens 5.

[0087] Specifically, as Figure 7 shown, since the first superlens 1 in the HCSEL light source 2 only expands the light beam in the line length direction of the one-dimensional line spot, the focusing lens 5 is arranged on the light output side of the HCSEL light source 2, and the focusing lens 5 is used to compress the light beam received by it in the line width direction of the one-dimensional line spot to obtain a one-dimensional line beam, and the one-dimensional line beam forms a one-dimensional line spot 4 on the target plane 3. It should be noted that in this embodiment, the focusing lens 5 can be either a second superlens or a cylindrical lens.

[0088] Furthermore, in this optical device, when the focusing lens 5 is a second superlens, the phase distribution of the second superlens satisfies any one of the following:

[0089]

[0090] where, is the focusing phase of the second superlens, f2 is the effective focal length of the second superlens, k is the wave number of the working center wavelength of the second superlens, y is the distance from the point on the line width direction of the one-dimensional line spot of the second superlens to the center point, N is the phase order, a i is the phase coefficient, is the phase constant.

[0091] In an embodiment, asFigure 12 As shown Figure 12 Figure 12 shows a schematic diagram of an optical device provided by an embodiment of the present application. When the focusing lens 5 is a second metalens, the phase of the second metalens further includes a deflection phase, and the deflection phase is used to deflect a one-dimensional line beam, so as to form an eccentric one-dimensional line spot 4 on the target plane 3.

[0092] It should be noted that the second metalens only compresses the beam in the line width direction of the one-dimensional line spot. Therefore, by superimposing the deflection phase on the original focusing phase of the second metalens, a distortion-free eccentric one-dimensional line beam can be generated, and the uniformity and straightness of the one-dimensional line beam can be maintained without obvious change, and then an eccentric and distortion-free one-dimensional line spot 4 is formed on the target plane 3. The deflection phase of the second metalens satisfies:

[0093]

[0094] Wherein, is the deflection phase of the second metalens, θ is the deflection angle, k is the wave number of the working center wavelength of the second metalens, and y is the distance from the point on the second metalens in the line length direction of the one-dimensional line spot to the center point.

[0095] In another embodiment, when the focusing lens 5 is a cylindrical lens, by translating the cylindrical lens in the line width direction of the one-dimensional line spot, a distortion-free eccentric one-dimensional line beam can also be generated.

[0096] Embodiment 1

[0097] The optical device provided by Embodiment 1 includes an HCSEL light source 2 integrated with a first metalens 1. The working wavelength of the HCSEL light source is 850 nm, and the size is 4 mm × 0.2 mm. After being modulated by the first metalens 1, the FOI (Field Of Illumination) of the beam output by the HCSEL light source 2 is 60°×23° (fast axis direction × slow axis direction); after the beam is modulated by the focusing lens 5, the one-dimensional line spot generated on the target plane at 25 cm is as Figure 13 As shown Figure 13 Figure 13 shows a schematic diagram of the light intensity distribution of the one-dimensional line spot projected by the optical device provided by Embodiment 1 of the present application.

[0098] When the focusing lens 5 is a second metalens, and the second metalens superimposes a deflection phase, so that the one-dimensional line beam deflected in the 10° direction generates a one-dimensional line spot on the target plane at 25 cm as Figure 14 As shown Figure 14 Figure 14 shows a schematic diagram of the light intensity distribution of the eccentric one-dimensional line spot projected by the optical device provided by Embodiment 1 of the present application. It can be seen that the one-dimensional line spot deviates from the optical axis and no distortion is generated.

[0099] Example 2

[0100] The HCSEL light source 2 in the optical device provided in Example 2 includes a plurality of light-emitting regions. The working center wavelength of each light-emitting region in the HCSEL light source 2 is 940 nm, and there is no integrated metalens in the HCSEL light source 2 in this example. The pitch of the light-emitting regions of each light-emitting region in the HCSEL light source 2 is 270 um. The divergence angle of the light beam emitted by each light-emitting region in the fast axis direction (the length direction of the one-dimensional line-shaped spot) is 12°, and the divergence angle in the slow axis direction (the width direction of the one-dimensional line-shaped spot) is 1°. The distance between the HCSEL light source 2 and the first metalens 1 is 765 um. The divergence angle of the directly emitted one-dimensional line-shaped light beam projected by this optical device in the fast axis direction is 120°, and the eccentric angles upward and downward are 15°. The distance between the target plane and the first metalens 1 is 300 mm. The spot array generated by this optical device is as Figure 15 shown Figure 15 shows a schematic diagram of the one-dimensional line-shaped spot array projected by the optical device provided in Embodiment 2 of the present application.

[0101] Example 3

[0102] The HCSEL light source 2 in the optical device provided in Example 3 includes a plurality of light-emitting regions. The working center wavelength of each light-emitting region in the HCSEL light source 2 is 940 nm, and there is no integrated metalens in the HCSEL light source 2 in this example. The pitch of the light-emitting regions of each light-emitting region in the HCSEL light source 2 is 270 um. The divergence angle of the light beam emitted by each light-emitting region in the fast axis direction (the length direction of the one-dimensional line-shaped spot) is 12°, and the divergence angle in the slow axis direction (the width direction of the one-dimensional line-shaped spot) is 1°. The distance between the HCSEL light source 2 and the first metalens 1 is 765 um. The divergence angle of the directly emitted one-dimensional line-shaped light beam projected by this optical device in the fast axis direction is 120°, and the eccentric angles upward and downward are 10°. The distance between the target plane and the first metalens 1 is 300 mm. The spot array generated by this optical device is as Figure 16 shown Figure 16 shows a schematic diagram of the one-dimensional line-shaped spot array projected by the optical device provided in Embodiment 3 of the present application.

[0103] Example 4

[0104] The HCSEL light source 2 in the optical device provided in Embodiment 4 includes a plurality of light-emitting regions. The operating wavelength of each light-emitting region in the HCSEL light source 2 is 940 nm, and there is no integrated metalens in the HCSEL light source 2 in this embodiment. The pitch of the light-emitting regions of each light-emitting region in the HCSEL light source 2 is 270 um. The divergence angle of the light beam emitted by each light-emitting region in the fast axis direction (the direction of the line length of the one-dimensional line spot) is 12°, and the divergence angle in the slow axis direction (the direction of the line width of the one-dimensional line spot) is 1°. The distance between the HCSEL light source 2 and the first metalens 1 is 765 um. The divergence angle of the directly emitted one-dimensional line beam projected by this optical device in the fast axis direction is 120°, and the eccentric angles upward and downward are 5°. The distance between the target plane and the first metalens 1 is 300 mm. The spot array generated by this optical device is as Figure 17 shown, Figure 17 which shows a schematic diagram of the one-dimensional line spot array projected by the optical device provided in Embodiment 4 of the present application.

[0105] After considering the specification and practicing the disclosed utility model herein, those skilled in the art will readily conceive of other embodiments of the present application. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include known common knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only regarded as exemplary, and the true scope and spirit of the present application are pointed out by the appended claims.

Claims

1. An optical device for generating a line light spot, characterized in that: The optical device comprises: a first superlens; a horizontal cavity surface emitting laser HCSEL light source; the first superlens comprises a first substrate and a first micro-nano structure arranged on the first substrate; The first super lens is used to expand the light beam received by it in the line length direction of the word-line light spot to modulate the light beam into a word-line light beam, and the word-line light beam is used to form a word-line light spot on the target plane.

2. The optical device according to claim 1, characterized in that The first super lens is arranged on the light-emitting side of the light-emitting region of the HCSEL light source; The fast axis direction of the HCSEL light source is parallel to the line length direction of the word line light spot, and the slow axis direction of the HCSEL light source is parallel to the line width direction of the word line light spot.

3. The optical device according to claim 2, characterized in that The HCSEL light source comprises a plurality of light-emitting regions, each of which is arranged in an array along the line length direction of a word line light spot; The effective area of ​​the first metalens includes a plurality of partitions, the number of the partitions is equal to the number of the light-emitting areas, and the partitions are matched one by one with the light-emitting areas; Each of the partitions is used to receive a light beam emitted by a corresponding light emitting area, and to expand the corresponding light beam in a line length direction of a word line spot, and to deflect the light beam in a line width direction.

4. The optical device according to claim 3, characterized in that The boundary line between adjacent partitions on the first super lens is parallel to the line width direction of the single-word line light spot, and the boundary line between adjacent partitions is perpendicular to the line length direction of the single-word line light spot.

5. The optical device according to claim 3, characterized in that Each partition on the first super lens is also used to compress the light beam received thereon in the line width direction of the word line spot.

6. The optical device according to claim 3, characterized in that Each partition on the first super lens is also used to collimate the light beam received thereon in the line length direction of the word line spot.

7. The optical device according to claim 1, characterized in that The first super lens is arranged on the light-emitting side of the light-emitting region of the HCSEL light source; The fast axis direction of the HCSEL light source is parallel to the line width direction of the word line light spot, and the slow axis direction of the HCSEL light source is parallel to the line length direction of the word line light spot.

8. The optical device according to any one of claims 2 to 7, characterized in that: The first super lens is arranged on the light-emitting side of the light-emitting region of the HCSEL light source, and includes: The first super lens is arranged outside the HCSEL light source; or, The first superlens is integrated inside the HCSEL light source.

9. The optical device according to claim 7, characterized in that When the first superlens is integrated inside the HCSEL light source, the optical device further comprises: a focusing lens; The focusing lens is arranged at the light-emitting side of the HCSEL light source, and is used to compress the light beam received by the focusing lens in the line width direction of the word line spot; Wherein, the focusing lens is a cylindrical lens or a second super lens.

10. The optical device according to claim 9, characterized in that When the focusing lens is a second super lens, the second super lens is further used to deflect the light beam received by it in the line width direction of the word line spot to form an eccentric word line spot.

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