A method and device for beam shaping of a planar light source based on holographic transmission

Abstract

The present invention discloses a method and device for beam shaping of a planar light source based on holographic transfer. Among them, the beams emitted by a plurality of planar light sources are respectively magnified and imaged by a plurality of first lenses to obtain magnified holograms of the plurality of planar light sources; then, the magnified holograms of the plurality of planar light sources are seamlessly spliced at a primary imaging position, so as to obtain a seamless light source at the primary imaging position. The above-mentioned method for beam shaping of a planar light source realizes the elimination of the gaps between light sources and further improves the beam quality of the light source as a whole through holographic transfer and seamless splicing with almost no loss of optical power. This optical shaping method is applicable to the shaping and processing of planar light sources such as VCSELs and LEDs.

Description

Technical Field

[0001] The present invention relates to a method for shaping a beam of a planar light source, and also relates to a device for shaping a beam of a planar light source, belonging to the field of optics. Background Art

[0002] In application fields such as high-power lasers and lighting, it is necessary to use multiple light-emitting devices to splice a large-sized light source or integrate a high-power light source. However, due to many limitations such as light source packaging, there is always a certain gap between multiple planar light sources on the same plane. And in many applications, in order to achieve a more uniform light intensity distribution, it is necessary to eliminate the influence of the non-light-emitting gaps in the initial light source. Summary of the Invention

[0003] The primary technical problem to be solved by the present invention is to provide a method for shaping a beam of a planar light source based on holographic transfer.

[0004] Another technical problem to be solved by the present invention is to provide a device for shaping a beam of a planar light source based on holographic transfer.

[0005] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0006] Based on the first aspect of the embodiments provided by the present invention, a method for shaping a beam of a planar light source based on holographic transfer is provided, including the following steps:

[0007] (1) Using multiple first lenses to respectively magnify and image the beams emitted by multiple planar light sources to obtain magnified holograms of the multiple planar light sources;

[0008] (2) Splicing the magnified holograms of the multiple planar light sources at a primary imaging position, and the magnified holograms of the multiple planar light sources are spliced into a seamless light source.

[0009] Preferably, along any section of the principal optical axis, the distance u between each of the planar light sources and the first lens and the distance v between the first lens and the primary imaging position simultaneously satisfy the following formula:

[0010]

[0011]

[0012] k - h = d;

[0013] Wherein, along any section of the principal optical axis, the size of the planar light source is h, the distance between adjacent light sources is d, the size of the magnified hologram of the planar light source at the primary imaging position is k; the full divergence angle of the planar light source is θ; the diameter of the first lens is D, and the focal length of the first lens is f.

[0014] Preferably, the method for shaping a planar light source beam based on holographic transmission further includes the following steps:

[0015] (3) Use a second lens to perform reduced imaging on the beam of the seamless light source obtained in step (2) to obtain a reduced seamless hologram.

[0016] Preferably, for any section along the principal optical axis, the distance u' between the primary imaging position and the second lens and the distance v' between the second lens and the secondary imaging position simultaneously satisfy the following formula:

[0017]

[0018] m > m';

[0019] Wherein, for any section along the principal optical axis, the size of the seamless light source is m, and the size of the reduced hologram of the seamless light source at the secondary imaging position is m'; the full divergence angle of the seamless light source is θ'; the diameter of the second lens is D', and the focal length of the second lens is f'.

[0020] Preferably, the planar light source used in step (1) is a planar light source whose beam can be tiled after being proportionally enlarged.

[0021] Preferably, the beam shape of the planar light source used in step (1) is a regularly shaped pattern that can be periodically repeated. For example, the beam shape of the planar light source used in step (1) is any one or more of a square, a rectangle, an isosceles triangle, an equilateral triangle, and a regular hexagon.

[0022] Preferably, the multiple planar light sources used in step (1) are simultaneously LED light sources or VCSEL light sources.

[0023] Based on the second aspect of the embodiments provided by the present invention, there is provided a device for shaping a planar light source beam based on holographic transmission, including:

[0024] A light source array composed of multiple planar light sources, and the multiple planar light sources are arranged in the same plane;

[0025] A lens group composed of multiple first lenses; the multiple first lenses and the multiple planar light sources are coaxially arranged in one-to-one correspondence, and the multiple first lenses are respectively used to perform enlarged imaging on the beams emitted by the multiple planar light sources to obtain enlarged holograms of the multiple planar light sources;

[0026] The distance between the multiple first lenses and the multiple planar light sources is such that the enlarged holograms of the multiple planar light sources are seamlessly tiled at the primary imaging position, so that the enlarged holograms of the multiple planar light sources are tiled into a seamless light source at the primary imaging position.

[0027] Preferably, for any section along the principal optical axis, the distance u between each of the planar light sources and the first lens and the distance v between the first lens and the primary imaging position simultaneously satisfy the following formula:

[0028]

[0029] k - h = d;

[0030] Wherein, for any section along the principal optical axis, the size of the planar light source is h, the distance between adjacent light sources is d, the size of the magnified hologram of the planar light source at the primary imaging position is k; the full divergence angle of the planar light source is θ; the diameter of the first lens is D, and the focal length of the first lens is f.

[0031] Preferably, the planar light source beam shaping device based on holographic transfer further includes a second lens, the second lens is coaxially arranged with the centers of the multiple planar light sources, and the second lens is arranged on the light emitting path of the seamless light source; the second lens is used to perform reduced imaging on the light beam emitted from the seamless light source to obtain a reduced seamless hologram.

[0032] Preferably, for any section along the principal optical axis, the distance u' between the primary imaging position and the second lens and the distance v' between the second lens and the secondary imaging position simultaneously satisfy the following formula:

[0033]

[0034]

[0035] m > m';

[0036] Wherein, for any section along the principal optical axis, the size of the seamless light source is m, the size of the reduced hologram of the seamless light source at the secondary imaging position is m'; the full divergence angle of the seamless light source is θ'; the diameter of the second lens is D', and the focal length of the second lens is f'.

[0037] Preferably, the multiple planar light sources are simultaneously LED light sources or VCSEL light sources.

[0038] Preferably, the planar light source is a planar light source whose light beam can be spliced after being proportionally enlarged.

[0039] Preferably, the light beam shape of the planar light source is a regular pattern that can be periodically repeated. For example, the light beam shape of the planar light source is any one or more of a square, a rectangle, an isosceles triangle, an equilateral triangle, and a regular hexagon.

[0040] The planar light source beam shaping method based on holographic transfer provided by the present invention magnifies and images the light beams of multiple planar light sources respectively through a plurality of first lenses, and obtains magnified holograms of the multiple planar light sources; then, seamless splicing is performed on the magnified holograms of the multiple planar light sources at the primary imaging position, so as to obtain a seamless light source at the primary imaging position. The above-mentioned planar light source beam shaping method eliminates the gaps between light sources through holographic transfer and seamless splicing with almost no loss of optical power, and further improves the beam quality of the light source as a whole. This optical shaping method is applicable to the shaping and processing of planar light sources such as VCSELs and LEDs. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 is a schematic diagram of the optical path principle of the planar light source beam shaping method based on holographic transfer provided by the present invention;

[0042] Figure 2 is a schematic diagram of the principle of obtaining magnified holograms of multiple planar light sources;

[0043] Figure 3 is a schematic diagram of the structure of a 2×2 light source array;

[0044] Figure 4 is a front view structural schematic diagram of the planar light source beam shaping device based on holographic transfer provided by the present invention;

[0045] Figure 5 is Figure 3 a schematic diagram of the light source array in

[0046] Figure 6 and the seamless light source obtained after its magnified imaging; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0047] The technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0048] As Figure 1 shown, the planar light source beam shaping method based on holographic transfer provided by the present invention includes the following steps:

[0049] (1) Use a plurality of first lenses (labeled as: 21, 22, 23, 24,...) to respectively magnify and image the light beams emitted by a plurality of planar light sources (labeled as: 11, 12, 13, 14,...), and obtain magnified holograms (31, 32, 33, 34,...) of the plurality of planar light sources;

[0050] (2) Stitch the magnified holograms (31, 32, 33, 34, ……) of multiple planar light sources at the primary imaging position 30, and the magnified holograms (31, 32, 33, 34, ……) of multiple planar light sources are stitched into a seamless light source S at the primary imaging position 30.

[0051] Among them, multiple planar light sources (11, 12, 13, 14, ……) serving as the initial light sources can be LED light sources or VCSEL light sources simultaneously. The multiple planar light sources can be a chip array or a discrete chip array located on the same wafer (for example, as Figure 3 shown).

[0052] The initial light source adopts a planar light source whose light beam can be stitched after being equally proportionally magnified. The shapes and sizes of multiple initial light sources can be the same or different. The light beam shape of the initial light source can be a closed regular shape or a closed irregular shape composed of straight lines, curves, etc. As long as the light beams of the multiple planar light sources for stitching meet the requirement that they can be stitched into a seamless plane after being equally proportionally magnified.

[0053] Preferably, the light beam shapes of the multiple planar light sources are recommended to use regularly shaped patterns that can be periodically repeated, so as to facilitate industrial production and the selection of relevant lenses. The above-mentioned regular patterns can be repeated along one, two or even more axes, and the included angle between different axes can be any angle. For example, planar light sources with light beam shapes such as squares, rectangles, isosceles triangles, equilateral triangles, regular hexagons, regular octagons, etc. can be used as the initial light sources. The light beam shapes of the multiple planar light sources for stitching can be one or more of the above shapes.

[0054] Multiple planar light sources (11, 12, 13, 14, ……) form a light source array with small size and spacing. Each planar light source constitutes a unit light source; the unit light sources arranged in adjacent rows or adjacent columns can be arranged correspondingly or staggeredly, as long as the light beams can be stitched into a seamless plane after being equally proportionally magnified.

[0055] A plurality of first lenses (21, 22, 23, 24, ……) form a lens group 20, and each first lens constitutes a unit lens. The plurality of first lenses in the lens group 20 are arranged in one-to-one correspondence with the plurality of planar light sources in the light source array. Among them, each first lens is coaxially arranged with a single planar light source, and each first lens and the corresponding planar light source are arranged parallel to each other along the same principal optical axis. For example, the first lens 21 is coaxially arranged with the planar light source 11, the first lens 22 is coaxially arranged with the planar light source 12, the first lens 23 is coaxially arranged with the planar light source 13, the first lens 24 is coaxially arranged with the planar light source 14, and so on. Each first lens is used to magnify and image the light beam emitted by the corresponding planar light source. The selection of each first lens requires that its light-transmitting aperture D should fully cover all the divergent light of the corresponding unit light source, and the imaging size of the unit light source (i.e., the size of the magnified hologram formed after imaging) should not be less than the maximum cross-section of the unit lens and the lens fixing device, so as to ensure that multiple holograms can be seamlessly spliced without mechanical size conflicts.

[0056] As Figure 2 shown, when using the lens group 20 to magnify and image the light source array, for any section along the principal optical axis, the distance u between each planar light source and the first lens and the distance v between the first lens and the primary imaging position 30 simultaneously satisfy the following formula:

[0057]

[0058] k - h = d; (4)

[0059] Among them, for any section along the principal optical axis, the size of a single planar light source is h, the distance between adjacent light sources is d, the size of the magnified hologram of the planar light source at the primary imaging position 30 is k; the full divergence angle of the planar light source is θ; the diameter of the first lens is D, and the focal length of the first lens is f. All the sizes of the planar light source obtained for any section along the principal optical axis and the corresponding magnified hologram sizes satisfy the above four formulas.

[0060] The image after the above splicing can be regarded as an independent planar light source and can be used for secondary imaging or other transformations with a lens again.

[0061] Specifically, the planar light source beam shaping method may further include the following steps: (3) Using the second lens 40 to reduce and image the light beam of the seamless light source S obtained in step (2) to obtain a reduced seamless hologram S', thereby obtaining a high-energy-density high-power seamless light source.

[0062] When using the second lens 40 to reduce and image the seamless light source S, for any section along the principal optical axis, the distance u' between the primary imaging position 30 and the second lens 40 and the distance v' between the second lens 40 and the secondary imaging position 50 simultaneously satisfy the following formula:

[0063]

[0064] m > m'; (8)

[0065] Among them, for any section along the principal optical axis, the size of the seamless light source S is m, and the size of the reduced hologram S' of the seamless light source S at the secondary imaging position is m'; the full divergence angle of the seamless light source S is θ'; the diameter of the second lens 40 is D', and the focal length of the second lens 40 is f'. All the sizes obtained from any section of the seamless light source S along the principal optical axis and the corresponding reduced hologram sizes satisfy the above four formulas.

[0066] The present invention also provides an apparatus for implementing the above-mentioned planar light source beam shaping method. As Figures 3 to 5 shown, the planar light source beam shaping apparatus based on holographic transfer provided by the present invention includes:

[0067] A light source array composed of a plurality of planar light sources (11, 12, 13, 14,...), and the plurality of planar light sources (11, 12, 13, 14,...) are arranged in the same plane;

[0068] A lens group 20 composed of a plurality of first lenses (21, 22, 23, 24,...); the plurality of first lenses and the plurality of planar light sources are coaxially arranged in one-to-one correspondence, and the plurality of first lenses (21, 22, 23, 24,...) are respectively used to perform magnified imaging on the light beams of the plurality of planar light sources (11, 12, 13, 14,...) to obtain magnified holograms (31, 32, 33, 34,...) of the plurality of planar light sources;

[0069] The distance between the plurality of first lenses (21, 22, 23, 24,...) and the plurality of planar light sources (11, 12, 13, 14,...) is such that the magnified holograms (31, 32, 33, 34,...) of the plurality of planar light sources are seamlessly spliced at the primary imaging position 30, so as to splice out a seamless light source S at the primary imaging position 30.

[0070] At the same time, it further includes a second lens 40, which is coaxially arranged with the centers of the plurality of planar light sources and is also coaxially arranged with the center of the seamless light source S. The second lens 40 is arranged on the light emitting path of the seamless light source S; the second lens 40 is used to perform reduced imaging on the light beam emitted from the seamless light source S to obtain a reduced seamless hologram S'.

[0071] Among them, the plurality of planar light sources (11, 12, 13, 14,...) serving as the initial light source can be LED light sources or VCSEL light sources at the same time, and the plurality of planar light sources can be a chip array or a discrete chip array located on the same wafer.

[0072] The initial light source uses a planar light source whose light beam can be spliced after being enlarged in equal proportion. The shapes and sizes of multiple initial light sources can be the same or different. The shape of the initial light source can be a closed regular shape or a closed irregular shape composed of straight lines, curves, etc. Multiple planar light sources for splicing only need to satisfy that the light beams can be spliced into a seamless plane after being enlarged in equal proportion.

[0073] Preferably, the light beam shapes of multiple planar light sources are recommended to use regularly arranged graphics that can be periodically repeated, which is convenient for industrial production and the selection of related lenses. The above-mentioned regular graphics can be repeated along one, two or even more axes, and the included angle between different axes can be any angle. For example, a planar light source with a light beam shape of any one of a square, a rectangle, an isosceles triangle, an equilateral triangle, a regular hexagon, etc. can be used as the initial light source.

[0074] Multiple planar light sources (11, 12, 13, 14, ……) form a light source array with small size and spacing. Each planar light source constitutes a unit light source; the unit light sources arranged in adjacent rows or columns can be arranged correspondingly or staggeredly for splicing.

[0075] Multiple first lenses (21, 22, 23, 24, ……) form a lens group 20, and each first lens constitutes a unit lens. The multiple first lenses in the lens group 20 are arranged in one-to-one correspondence with the multiple planar light sources in the light source array. Among them, each first lens is arranged parallel to a single planar light source along the same principal optical axis. For example, the first lens 21 is coaxially arranged with the planar light source 11, the first lens 22 is coaxially arranged with the planar light source 12, the first lens 23 is coaxially arranged with the planar light source 13, the first lens 24 is coaxially arranged with the planar light source 14, and so on. Each first lens is used to magnify and image the light beam emitted by the corresponding planar light source. The selection of each first lens requires that its light passing aperture fully covers all the divergent light of the corresponding unit light source, and the imaging size of the unit light source should not be less than the maximum cross-section of the unit lens and the lens fixing device to ensure that multiple holograms can be seamlessly spliced without mechanical size conflicts.

[0076] As Figure 2 shown, when using the lens group 20 to magnify and image the light source array, for any section along the principal optical axis, the distance u between each planar light source and the first lens and the distance v between the first lens and the primary imaging position 30 simultaneously satisfy the following formula:

[0077]

[0078] k - h = d; (4)

[0079] Among them, for any section along the principal optical axis, the size of a single planar light source is h, the spacing between adjacent light sources is d, and the size of the magnified hologram of the planar light source at the primary imaging position 30 is k; the full divergence angle of the planar light source is θ; the diameter of the first lens is D, and the focal length of the first lens is f. All the sizes obtained from any section of the planar light source along the principal optical axis and the corresponding magnified hologram sizes satisfy the above four formulas.

[0080] When using the second lens 40 to perform reduced imaging on the seamless light source S, for any section along the principal optical axis, the distance u' between the primary imaging position 30 and the second lens 40 and the distance v' between the second lens 40 and the secondary imaging position 50 simultaneously satisfy the following formulas:

[0081]

[0082] m > m'; (8)

[0083] Among them, for any section along the principal optical axis, the size of the seamless light source S is m, and the size of the reduced hologram S' of the seamless light source at the secondary imaging position 50 is m'; the full divergence angle of the seamless light source S is θ'; the diameter of the second lens 40 is D', and the focal length of the second lens 40 is f'. All the sizes obtained from any section of the seamless light source along the principal optical axis and the corresponding reduced hologram sizes satisfy the above four formulas.

[0084] In the following text, in combination with Figures 3 to 5 , taking the 2×2 light source array composed of 4 square planar light sources (11, 12, 13, 14) as an example, the corresponding planar light source beam shaping device will be specifically introduced.

[0085] As Figure 3 shown, the 2×2 light source array is composed of 4 square planar light sources (11, 12, 13, 14). The planar light sources (11, 12, 13, 14) are simultaneously LED light sources or VCSEL light sources. The 4 planar light sources can be a chip array on the same wafer or a discrete chip array in the same plane. The initial light source adopts a square structure to facilitate the splicing of its imaging. The 4 planar light sources (11, 12, 13, 14) form a 2×2 light source array with a size of h' and a spacing of d'. The 4 unit light sources are vertically and evenly arranged in a "field" shape in the same plane. The beam shape of each planar light source is square, and the light emitting area is h'×h'.

[0086] As Figure 4As shown in the figure, four first lenses (21, 22, 23, 24) form a lens group 20. Among them, the first lens 21 is coaxially arranged with the planar light source 11, the first lens 22 is coaxially arranged with the planar light source 12, the first lens 23 is coaxially arranged with the planar light source 13, and the first lens 24 is coaxially arranged with the planar light source 14. Each first lens is used to magnify and image the light beam emitted by the corresponding planar light source. The selection requirement for each first lens is that its clear aperture D should fully cover all the divergent light of the corresponding unit light source, and the imaging size of the unit light source should not be less than the maximum cross-section of the unit lens and the lens fixing device, so as to ensure that multiple holograms can be seamlessly spliced without mechanical size conflicts.

[0087] For a planar light source array with small size and spacing, such as a regularly arranged VCSEL light source, the lens group 20 can be made into a microlens array (compound eye lens). The first lenses in the lens group 20 can be spherical convex lenses, aspherical lenses or Fresnel lenses, etc.

[0088] The primary imaging position 30, the second lens 40 and the secondary imaging position 50 are all coaxially arranged with the center line of the light source array. The selection requirement for the second lens 40 is that its clear aperture D' should fully cover all the divergent light of the seamless light source S.

[0089] As Figure 3 shown, for a light source array composed of 4 square planar light sources (11, 12, 13, 14), among all the sizes obtained in any cross-section along the principal optical axis, the size in the diagonal direction is the largest. Therefore, in the following text, based on the size in the diagonal direction of the light source array, the sizes of the first lens and the second lens, as well as the distances between the first lens and the primary imaging position 30, between the primary imaging position 30 and the second lens 40, and between the second lens 40 and the secondary imaging position 50 are calculated.

[0090] Specifically, when using the lens group 20 to magnify and image the light source array, the distance u between each square planar light source and the first lens and the distance v between the first lens and the primary imaging position 30 simultaneously satisfy the following formula:

[0091]

[0092] L’ - L = L0; (11)

[0093] Among them, the side length of the square planar light source is h’, the diagonal length is L, the distance between adjacent light sources on the diagonal is L0, the diagonal size of the magnified hologram of the square planar light source at the primary imaging position 30 is L’; the full divergence angle of the planar light source is θ; the diameter of the first lens is D, and the focal length of the first lens is f.

[0094] At the primary imaging position 30, the size of the seamless light source S along the diagonal direction of the light source array, i.e., the original size of the seamless light source S, is m, and m = 2×L'. (12)

[0095] When using the second lens 40 to perform reduced imaging on the seamless light source S, the distance u' between the primary imaging position 30 and the second lens 40 and the distance v' between the second lens 40 and the secondary imaging position 50 simultaneously satisfy the following formula:

[0096]

[0097] m' < m; (8)

[0098] Wherein, along any section of the principal optical axis, the size of the seamless light source S is m, and the size of the reduced hologram S' of the seamless light source at the secondary imaging position is m'; the full divergence angle of the seamless light source S is θ'; the diameter of the second lens 40 is D', and the focal length of the second lens is f'.

[0099] For Figure 3 the light source array shown, since the initial light source itself is composed of 4 square light sources, it is impossible to eliminate the gaps between the 4 light sources using a single spherical lens or a single spherical mirror. In the planar light source beam shaping device provided by the present invention, 4 first lenses (i.e., the lens group 20) are used to form enlarged holograms of the 4 unit light sources respectively. Then, the enlarged holograms of the 4 unit light sources are spliced at the primary imaging position 30. In this way, a seamless spliced hologram S can be obtained from the 4 slit planar light sources. As Figure 5 shown, the 4 unit light sources are respectively the planar light sources 11, 12, 13, and 14. After enlarged imaging, enlarged holograms 31, 32, 33, and 34 of the 4 unit light sources are obtained. By adjusting the set distance between the light source array and the lens group 20, the enlarged holograms 31, 32, 33, and 34 of the 4 unit light sources can be seamlessly spliced at the primary imaging position 30, thereby obtaining a seamless light source S as Figure 5 shown. Among them, in Figure 5 , for the sake of easy understanding, the splicing boundaries of the enlarged holograms of the 4 unit light sources are shown by dotted lines. However, in the actual seamless light source S, by adjusting the spacing between the multiple planar light sources and the lens group 20, the 4 enlarged holograms have been seamlessly spliced into a whole at the primary imaging position 30. Therefore, there is no visible boundary as shown in the figure. The above 4 spliced enlarged holograms can be regarded as a uniform seamless light source S, and then subsequent imaging transformation can be performed again. For example, a second lens 40 with a larger aperture can be used to perform secondary reduced imaging (hologram imaging) on this hologram, and a reduced seamless hologram S' can be obtained.

[0100] In order to evaluate the influence of the above beam shaping method on the beam quality, the present invention uses the Beam Parameter Product (BPP) to evaluate the beam quality of the initial light source and the enlarged seamless hologram. BPP = waist radius × far-field divergence angle.

[0101] Taking a 2×2 light source array composed of 4 square planar light sources as an example below, the beam quality of the initial light source and the seamless light source S obtained after splicing and amplifying the hologram is evaluated. For the light source array composed of 4 square planar light sources (11, 12, 13, 14), among all the dimensions obtained in any section along the main optical axis, the dimension in the diagonal direction is the largest. Therefore, the beam quality is evaluated based on the dimension in the diagonal direction of the light source array.

[0102] The side length of the square planar light source is h', and the light-emitting area of the planar light source is h'×h'; the diagonal length of the square planar light source is L, and the distance between adjacent light sources in the diagonal direction is L0; the full angle of the divergence angle of the planar light source is θ.

[0103] Assume that the unit planar light source is a Gaussian beam. According to the transmission characteristics of the Gaussian beam, the beam parameter product of its unit light source remains basically unchanged when passing through a thin lens. Here, for the waist, we approximate it with the size of the initial light source; and for the far-field divergence angle, we approximate it with the full angle θ of the divergence angle of the initial light source.

[0104] The initial light source is regarded as a whole, and the beam parameter product in the diagonal direction In the spliced hologram S, the beam parameter product BPP1 of each unit image in the diagonal direction = the beam parameter product of the unit light source Therefore, the beam parameter product of the spliced hologram in the vertical direction is smaller than the beam parameter product BPP0 of the initial light source as a whole.

[0105] It can be seen from this that this beam shaping method not only eliminates the gaps in the light source, but also eliminates the interference of the gaps on the beam quality, improving the overall beam quality to facilitate those application scenarios with high requirements for beam quality.

[0106] The above only takes the 2×2 square light source array as an example to compare the beam quality of the seamless light source obtained after holographic transfer and seamless splicing with the beam quality of the initial light source. The above evaluation method can also be understood as the evaluation of the beam quality of a light source array with two light sources in any section along the main optical axis. It can be concluded that the above beam shaping method not only eliminates the gaps in the light source, but also eliminates the interference of the gaps on the beam quality, improving the overall beam quality to facilitate those application scenarios with high requirements for beam quality. For a light source array composed of more than 4 planar light sources, the same conclusion can also be obtained, which will not be elaborated here.

[0107] In other words, the planar light source beam shaping method and device based on holographic transfer provided by the present invention can also be applied to more planar light sources whose beam shapes can be spliced into a plane after being proportionally enlarged. For example, in Figure 6 FIG. shows a schematic structural diagram of a seamless light source 60 obtained by magnifying and splicing holograms of multiple equilateral triangular planar light sources. Among them, for the sake of easy understanding, the splicing boundaries of the magnified holograms of multiple unit light sources are shown by dashed lines. However, in the actual seamless light source 60, by adjusting the distance between the lens group 20 and the primary imaging position 30, multiple magnified holograms are seamlessly spliced to form an integral whole. Therefore, there is no visible boundary as shown in the figure. For other planar light sources that can be spliced after being proportionally enlarged, the principles of holographic transfer and seamless splicing are similar to those of the above embodiments and will not be elaborated in detail here.

[0108] To sum up, in the planar light source beam shaping method based on holographic transfer provided by the present invention, the beams of multiple planar light sources are magnified and imaged by multiple first lenses to obtain magnified holograms of multiple planar light sources. Then, by splicing the magnified holograms of multiple planar light sources, a seamless light source can be obtained at the primary imaging position. The above planar light source beam shaping method realizes the elimination of the gaps between light sources and further improves the beam quality of the light source as a whole through holographic transfer and seamless splicing with almost no loss of optical power. This optical shaping method is applicable to the shaping and processing of planar light sources such as VCSEL and LED.

[0109] The above has described in detail a planar light source beam shaping method and device based on holographic transfer provided by the present invention. For those of ordinary skill in the art, any obvious changes made to it without departing from the essential spirit of the present invention will constitute an infringement of the patent right of the present invention and will bear corresponding legal responsibilities.

Claims

1. A method for shaping a light beam of a planar light source based on holographic transfer, characterized in that comprising the following steps: (1) Using a plurality of first lenses to respectively perform magnifying imaging on the light beams emitted by a plurality of planar light sources, and obtaining magnified holograms of the plurality of planar light sources; (2) Stitching the magnified holograms of the plurality of planar light sources at a primary imaging position, and stitching the magnified holograms of the plurality of planar light sources into a seamless light source; wherein, for any section along the principal optical axis, the distance u between each of the planar light sources and the first lens and the distance v between the first lens and the primary imaging position simultaneously satisfy the following formula: ； ； ； ； wherein, for any section along the principal optical axis, the size of the planar light source is h, the spacing between adjacent light sources is d, the size of the magnified hologram of the planar light source at the primary imaging position is k; the full divergence angle of the planar light source is θ; the diameter of the first lens is D, and the focal length of the first lens is f.

2. The planar light source beam shaping method according to claim 1, characterized in that It further comprises the following steps: (3) Using a second lens to perform reducing imaging on the light beam of the seamless light source obtained in step (2), and obtaining a reduced seamless hologram.

3. The planar light source beam shaping method according to claim 2, wherein: For any section along the principal optical axis, the distance u' between the primary imaging position and the second lens and the distance v' between the second lens and the secondary imaging position simultaneously satisfy the following formula: ； ； ； ； wherein, for any section along the principal optical axis, the size of the seamless light source is m, the size of the reduced hologram of the seamless light source at the secondary imaging position is m'; the full divergence angle of the seamless light source is θ'; the diameter of the second lens is D', and the focal length of the second lens is f'.

4. The planar light source beam shaping method according to claim 1, wherein: The planar light source used in step (1) is a planar light source whose light beam can be stitched after being proportionally magnified.

5. The planar light source beam shaping method according to claim 4, wherein: The light beam shape of the planar light source used in step (1) is a regular pattern that can be periodically and repeatedly arranged.

6. The planar light source beam shaping method according to claim 4, wherein: The light beam shapes of the plurality of planar light sources used in step (1) are any one or more of square, rectangle, isosceles triangle, equilateral triangle, and regular hexagon.

7. The planar light source beam shaping method according to claim 1, wherein: The plurality of planar light sources used in step (1) are simultaneously LED light sources or VCSEL light sources.

8. A planar light source beam shaping device based on holographic transfer, characterized in that Comprising: A light source array composed of a plurality of planar light sources, and the plurality of planar light sources are arranged in the same plane; A lens group composed of a plurality of first lenses; The plurality of first lenses and the plurality of planar light sources are coaxially arranged in one-to-one correspondence, and the plurality of first lenses are respectively used to perform magnifying imaging on the light beams emitted by the plurality of planar light sources, and obtain magnified holograms of the plurality of planar light sources; The distance between the plurality of first lenses and the plurality of planar light sources is such that the magnified holograms of the plurality of planar light sources are seamlessly stitched at the primary imaging position, so that the magnified holograms of the plurality of planar light sources are stitched into a seamless light source at the primary imaging position; Among them, for any section along the principal optical axis, the distance u between each of the planar light sources and the first lens and the distance v between the first lens and the primary imaging position simultaneously satisfy the following formula: ； ； ； ； Among them, for any section along the principal optical axis, the size of the planar light source is h, the spacing between adjacent light sources is d, and the size of the magnified hologram of the planar light source at the primary imaging position is k; the full divergence angle of the planar light source is θ; the diameter of the first lens is D, and the focal length of the first lens is f.

9. The planar light source beam shaping device according to claim 8, wherein It further includes a second lens, which is coaxially arranged with the centers of multiple planar light sources, and the second lens is arranged on the light-emitting path of the seamless light source; the second lens is used to perform reduced imaging on the light beam emitted from the seamless light source to obtain a reduced seamless hologram.

10. The planar light source beam shaping device according to claim 9, wherein: For any section along the principal optical axis, the distance u' between the primary imaging position and the second lens and the distance v' between the second lens and the secondary imaging position simultaneously satisfy the following formula: ； ； ； ； Among them, for any section along the principal optical axis, the size of the seamless light source is m, and the size of the reduced hologram of the seamless light source at the secondary imaging position is m'; the full divergence angle of the seamless light source is θ'; the diameter of the second lens is D', and the focal length of the second lens is f'.

11. The planar light source beam shaping device according to claim 8, wherein: The multiple planar light sources are simultaneously LED light sources or VCSEL light sources.

12. The planar light source beam shaping device according to claim 8, wherein: The planar light source is a planar light source that can be spliced after the beam is enlarged in equal proportion.

13. The planar light source beam shaping device according to claim 12, wherein: The beam shape of the planar light source is a regular pattern that can be periodically and repeatedly arranged.

14. The planar light source beam shaping device according to claim 12, wherein: The beam shapes of the multiple planar light sources are any one or more of a square, a rectangle, an isosceles triangle, an equilateral triangle, and a regular hexagon.

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