WO2020024583A1

WO2020024583A1 - Wavelength conversion element and preparation method therefor

Info

Publication number: WO2020024583A1
Application number: PCT/CN2019/076649
Authority: WO
Inventors: 徐梦梦; 胡飞; 王霖; 王杰; 李屹
Original assignee: 深圳光峰科技股份有限公司
Priority date: 2018-08-02
Filing date: 2019-03-01
Publication date: 2020-02-06
Also published as: CN110797448A; CN110797448B

Abstract

The present invention relates to a wavelength conversion element and a preparation method therefor. The wavelength conversion element comprises a transparent substrate, a partition, and a wavelength conversion part. The transparent substrate comprises a protruding first optical unit arranged in an array. The partition comprises a recessed second optical unit arranged in an array, wherein the transparent substrate is provided on the partition, such that the first optical unit of the first optical unit and the second optical unit of the partition are in one to one correspondence and face each other. The wavelength conversion part is provided at a protruding top portion of the first optical unit of the transparent substrate and at a recessed bottom portion of the second optical unit of the partition, and is arranged between the partition and the transparent substrate.

Description

Wavelength conversion element and preparation method thereof

Technical field

The present invention relates to a wavelength conversion element and a method for manufacturing the same, and in particular, to a wavelength conversion element and a method for manufacturing the same that reduce the difficulty of manufacturing a pixelated wavelength conversion element.

Background technique

In the current display field, the display method mainly uses DMD or LCD as a light modulator to modulate the illumination light to obtain image light. However, DMD technology is in the hands of American companies, while LCD technology is in the hands of Japanese companies, forming a technology monopoly. New companies enter the display field and cannot bypass these technologies, which is not conducive to reducing the cost of the display field. In addition, display devices based on DMD or LCD technology have defects in their efficiency, which severely restricts high-brightness displays.

In view of this problem, the applicant has proposed a display system with a fluorescent chip structure, and also proposed a specific structure and a manufacturing method of a pixelated wavelength conversion element suitable for the display system. In addition, Osram Corporation has proposed the structure of a wavelength conversion element suitable for a pixelated light-emitting device and a method for preparing the same in patent applications with publication numbers of WO2016087600, DE102013105533, CN105684171, and CN106030836.

FIG. 1 shows a schematic diagram of such a pixelated wavelength conversion element 100, wherein reference numeral 110 represents a wavelength conversion material, reference numeral 120 represents a light blocking material, and reference numeral 130 represents a substrate. FIG. 1 shows a plan view of the wavelength conversion element in the upper part, and a longitudinal sectional view of the wavelength conversion element in the lower part. As shown in FIG. 1, on the substrate 130, the wavelength conversion material 110 is formed to be spaced apart from each other by the light blocking material 120, thereby forming a pixel point array to convert incident light into light with another wavelength distribution. The light blocking material 120 does not transmit ultraviolet or / and visible light to prevent light crosstalk between different pixels. The display system using this structure can effectively improve the utilization rate of light, which is a development direction of future display systems.

In a method of manufacturing a pixelated wavelength conversion element in the related art, generally, an array of pits is formed on a barrier material, and then the wavelength conversion material is filled. Alternatively, an array of pits is formed on the wavelength conversion material and then filled with a blocking material.

Specifically, FIG. 2 illustrates such a manufacturing method of a pixelated wavelength conversion element generally used in the prior art.

As shown in FIG. 2 (a), the first preparation method directly or indirectly patterns the wavelength conversion material 110. Direct patterning is, for example, mechanical processing or laser etching, while indirect patterning is, for example, patterning using a photoresist as a template. After the pit array 111 is formed in the wavelength conversion material by the above-mentioned patterning, the pit array 111 is filled with the barrier material 120 to obtain a pixelated wavelength conversion element.

As shown in FIG. 2 (b), the second preparation method first performs similar direct or indirect patterning on the barrier material 120. After the pit array 121 is formed in the barrier material 120 by the above patterning, the pit array 121 is filled with the wavelength conversion material 110, thereby obtaining a pixelated wavelength conversion element. For example, the substrate 130 may be omitted in (b) of FIG. 2.

In these two preparation methods, since the size of a single pit is required to be tens to hundreds of microns, in this type of preparation method, direct or indirect patterning of the wavelength conversion material or the barrier material usually requires the use of precision machining or laser Etching, lithography and other methods are used to process the pit array. As a result, these preparation processes are complicated and require high equipment.

Summary of the invention

The present invention is made in view of the above problems, and aims to provide a pixelated wavelength conversion element and a manufacturing method thereof. The structure of the pixelated wavelength conversion element includes a light-transmitting substrate such as a lens array or a prism array. It plays the role of mold during the preparation process. The pixelated wavelength conversion with this structure uses a lens array or a prism array as a mold, which greatly reduces the difficulty of preparing the pixelated wavelength conversion element.

In addition, process parameters and material parameters can be controlled so that an air gap is generated at the surface of the lens array or prism array, thereby exerting its own light-shaping effect, light-shaping the light emitted by the wavelength conversion material, and obtaining pixels with specific angular distribution Into outgoing light.

According to an aspect of the present invention, a wavelength conversion element is provided. The wavelength conversion element may include: a light-transmitting substrate, the light-transmitting substrate including an array of first optical units having protrusions, and a blocking portion. The blocking portion includes second optical units with grooves arranged in an array, and the transparent substrate is arranged on the blocking portion, so that the first optical unit of the transparent substrate and the blocking The second optical units of the first optical unit correspond to each other and face each other; and a wavelength conversion unit disposed on top of the protrusions of the first optical unit of the transparent substrate and A bottom of the groove of the second optical unit of the blocking portion is interposed between the blocking portion and the transparent substrate.

In addition, the light-transmitting substrate may be a lens array including a hemispherical lens unit as the first optical unit. Alternatively, the transparent substrate may be a prism array including a prism-shaped prism unit as the first optical unit.

In addition, an air gap may be formed between the light-transmitting substrate and the blocking portion and / or between the light-transmitting substrate and the wavelength conversion portion.

In addition, the blocking portion may be formed by dispersing scattering particles in silica gel, photo-curing glue, or glass and curing.

In addition, the scattering particles may be one or more of TiO ₂ , Al ₂ O ₃ , MgO, and BaSO ₄ .

In addition, the wavelength conversion portion may be formed by dispersing a light-emitting material in silica gel, a photo-curing adhesive, or glass and curing it.

In addition, the light emitting material may be a rare earth phosphor or a quantum dot.

According to another aspect of the present invention, a method for preparing a wavelength conversion element is provided. The method includes: in a first step, coating a luminescent material slurry on a flat substrate to form a luminescent material slurry. Layer; in a second step, covering the light-emitting material paste layer with a light-transmitting substrate including a first optical unit having protrusions arranged in an array, so that The luminescent material paste is adhered at the top; in a third step, the light-transmitting substrate to which the luminescent material paste is adhered is removed, and the adhered luminescent material paste is pre-cured To form a pre-cured wavelength conversion portion; and in a fourth step, a blocking portion is formed on the structure to include a second optical unit with grooves arranged in an array. The fourth step is performed by one of the following methods: (a) flip the structure obtained in the third step, and apply the scattering particle slurry on the convex side of the light-transmitting substrate to form the scattering particle slurry Layer, and curing the structure obtained at this time, thereby obtaining the wavelength conversion element including the light-transmitting substrate, the blocking portion, and the wavelength conversion portion; and (b) coating the scattering particle slurry on another Forming a scattering particle slurry layer on a flat substrate, covering the structure obtained in the third step on the scattering particle slurry layer, curing the structure obtained at this time, and removing the other flat substrate, Thereby, the wavelength conversion element including the light-transmitting substrate, the blocking portion, and the wavelength conversion portion is obtained.

In addition, the second step to the third step may be repeatedly performed two or more times so that the wavelength conversion section has a predetermined thickness.

In addition, the expansion or contraction rate of the material of the light-transmitting substrate may be different from the expansion or contraction rate of the luminescent material slurry and / or the scattering particle slurry, so that during the curing in the fourth step, the An air gap is formed between the light-transmitting substrate and the blocking portion and / or between the light-transmitting substrate and the wavelength conversion portion.

In addition, the scattering particle slurry layer may be formed by dispersing scattering particles in silica gel, light-curing glue, or glass.

In addition, the luminescent material paste layer may be formed by dispersing a luminescent material in silica gel, a photo-curing glue, or glass.

According to the present invention, the prism array functions as a mold, thereby greatly simplifying the preparation difficulty of the pixelated wavelength conversion element during the preparation process of the wavelength conversion element.

In addition, according to the present invention, an air gap is formed at the surface of the light-transmitting substrate by controlling process parameters, material parameters, and the like, and the light-shaping effect of the light-transmitting substrate itself can be exerted to light-shape the light emitted by the wavelength conversion material To obtain the pixelated outgoing light with a specific angular distribution.

The technical solution of the present invention will be described in detail below with reference to the drawings and specific embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments are briefly introduced below. The drawings in the following description are just some embodiments of the present invention. For those of ordinary skill in the art, other embodiments and drawings can be obtained according to the embodiments shown in the drawings without paying creative labor.

FIG. 1 illustrates a configuration of a pixelated wavelength conversion element according to the related art.

FIG. 2 illustrates a method of preparing a pixelated wavelength conversion element according to the related art.

FIG. 3 is a cross-sectional view showing a specific configuration of the wavelength conversion element according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view illustrating a method of manufacturing a wavelength conversion element according to the first embodiment of the present invention.

5 is a cross-sectional view showing a specific configuration of a wavelength conversion element according to a second embodiment of the present invention.

detailed description

The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Note that the drawings are schematic and are not drawn based on actual scale. The relative dimensions and proportions of the components illustrated in the drawings are enlarged or reduced in size, and any dimensions are merely exemplary and not restrictive. The same structures, elements or components in the drawings are denoted by the same reference numerals.

First embodiment

As shown in FIG. 3, the wavelength conversion element according to the first embodiment of the present invention includes a wavelength conversion portion 11, a blocking portion 12 for optically isolating and / or light scattering the wavelength conversion portion 11, and a light-transmitting substrate. Lens array 13. Specifically, the lens array 13 is disposed on the blocking portion 12, and the wavelength conversion portion 11 is interposed between the blocking portion 12 and the lens array 13.

Here, the forming material of the light-transmitting substrate is a light-transmitting material, that is, it allows transmission of the excitation light to be converted by the wavelength conversion element and also allows the converted light to transmit; the light-transmitting material transmits light The rate is greater than 30%. Therefore, the lens array 13 as a light-transmitting substrate shapes the incident excitation light and guides it to the wavelength conversion section 11. At the same time, the light converted by the wavelength conversion section 11 can be emitted to the outside through the lens array 13.

In this embodiment, the lens unit of the lens array 13 has a hemispherical protrusion. However, the present invention is not limited to this. In the present invention, the shape of the lens unit of the lens array 13 may have any convex shape according to actual needs.

The protrusion of the lens unit can play the role of mold and positioning during the preparation of the wavelength conversion element, thereby greatly simplifying the difficulty of preparing the pixelated wavelength conversion element.

For example, in a planar arrangement, the arrangement of the plurality of lens units in the lens array 13 may be, but is not limited to, a matrix array similar to that shown in FIG. 1, and may also be another array, for example. For example, the lens units in the lens array 13 may be arranged in a compound eye structure.

The surfaces facing each other between the blocking portion 12 and the lens array 13 have a substantially matching shape. Specifically, as shown in FIG. 3, a surface of the lens array 13 facing the blocking portion 12 is formed with a convex lens unit, and at the same time, a surface of the blocking portion 12 facing the lens array 13 is formed with each lens unit Corresponding or matching grooves. As a result, a light isolation and / or light scattering unit is formed on the blocking portion 12. The light isolation and / or light scattering units on the blocking portion 12 correspond to the lens units of the lens array 13 one-to-one. The light-isolation and / or light-scattering unit can be used to avoid light crosstalk between adjacent wavelength conversion sections, and can also make more light emitted from the upper surface of the lens array 13 by its own diffuse reflection characteristics.

The material for forming the barrier portion 12 is formed by dispersing scattering particles for scattering excitation light in silica gel, light-curing glue, or glass, so that the barrier portion 12 has optical isolation and / or diffuse reflection characteristics. Here, for example, the scattering particles may be one or more of white particles such as TiO ₂ , Al ₂ O ₃ , MgO, and BaSO ₄ .

The blocking portion 12 can avoid light crosstalk between the adjacent wavelength conversion portions 11. At the same time, the diffuse reflection characteristic of the blocking portion 12 also allows more light to be emitted from the upper surface of the lens array 13.

The wavelength conversion section 11 may be provided to correspond to the light isolation and / or light scattering unit of each lens unit and the blocking section 12 in the lens array 13, and thus has light corresponding to the light of the lens unit and the blocking section 12 in the lens array 13. Corresponding number of isolation and / or light scattering units. Specifically, each wavelength conversion portion 11 may be disposed at the convex top of the corresponding lens unit and the bottom of the groove of the light isolating and / or light scattering unit on the blocking portion 12, and thus interposed between the blocking portion 12 and the lens array 13 between.

The forming material of the wavelength conversion portion 11 is formed by dispersing a light-emitting material in silica gel, a photo-curing adhesive, or glass. Here, for example, the light-emitting material may be a common rare earth phosphor or a quantum dot, etc., and is preferably a rare earth phosphor.

The wavelength conversion element can receive a modulating excitation light incident from above (upper side in FIG. 3). Here, for example, a blue laser light may be selected as the excitation light, and a preferred blue laser light may be a wavelength of 473 nm, such as a laser light obtained from a semiconductor laser.

Specifically, the excitation light is incident through the upper surface of the lens array 13 and passes through the lens array 13 so as to reach the wavelength conversion section 11. The wavelength conversion section 11 performs wavelength conversion on the incident excitation light to convert it into light with a specific wavelength distribution.

The wavelength conversion portion 11 and the lens array 13 and / or the blocking portion 12 and the lens array 13 may be optical contact or non-optical contact, and preferably non-optical contact.

In the case of optical contact, the lens array 13 functions only as a support and a template.

On the other hand, in the case of non-optical contact, an air gap that causes non-optical contact is formed between the wavelength conversion section 11 and / or the blocking section 12 and the lens array 13 so that each lens unit can function independently. The light emitted from each of the wavelength conversion sections 11 (that is, pixels) is subjected to light shaping to obtain pixelated emitted light having a specific angular distribution.

As shown in FIG. 4 (a), first, a luminescent material paste prepared in advance is coated on a flat substrate to form a paste layer containing a luminescent material. For example, the luminescent material paste is a mixed paste prepared by dispersing the luminescent material in silica gel, light-curing glue, or glass powder.

Then, as shown in FIG. 4 (b), the lens array 13 is covered on the luminescent material paste layer so that a certain amount of the luminescent material paste is adhered to the top of the lens unit in the lens array 13.

Then, as shown in FIG. 4 (c), the lens array 13 to which the luminescent material paste is adhered is removed from the luminescent material paste layer, and the adhered luminescent material paste is heated or light irradiated, so that The wavelength conversion material adhered to the lens unit is pre-cured to obtain a structure in which the wavelength conversion portion 11 is formed on the lens array 13.

By controlling parameters such as the thickness of the luminescent material paste layer and the force exerted on the lens array when the lens array is covered on the luminescent material paste layer, it is possible to control the wavelength conversion attached to the single lens unit of the lens array 13 The size of the section 11.

In order to obtain the wavelength conversion portion 11 with a predetermined thickness, the process of (b) to (c) of FIG. 4 may be repeatedly performed two or more times.

Then, a barrier portion 12 is formed on the structure shown in FIG. 4 (c). For example, two different manufacturing methods may be used to form the barrier portion 12.

As shown in (d1) of FIG. 4, in the first preparation method, the structure obtained in the process shown in FIG. 4 (c) is reversed, and the convex side of the lens array 13 is coated by a method such as blade coating. Cover the previously prepared scattering particle slurry to form a slurry layer containing scattering particles. For example, the scattering particle slurry is a mixed slurry prepared by dispersing the scattering particles in silica gel, light-curing glue, or glass frit.

Finally, the structure obtained at this time is cured by, for example, heating or light irradiation to form the barrier portion 12, thereby obtaining a pixelated wavelength conversion element as shown in FIG. 4 (e).

On the other hand, in the second preparation method, the scattering particle slurry is first coated on a flat substrate to form a slurry layer containing the scattering particles. Then, as shown in FIG. 4 (d2), the scattering particle slurry layer is covered with the structure shown in FIG. 4 (c) so that the convex side of the lens array 13 faces the scattering particle slurry layer.

By controlling parameters such as the thickness of the scattering particle slurry layer and the force applied to the lens array 13, the scattering particle slurry can completely or partially fill the gap between adjacent lens units of the lens array.

Finally, for example, the obtained structure is cured by heating or light irradiation to form the barrier portion 12, and the flat substrate is removed, thereby obtaining a pixelated wavelength conversion element as shown in FIG. 4 (e).

Regardless of whether the first preparation method shown in (d1) of FIG. 4 or the second preparation method shown in (d2) of FIG. 4 is used, a surface of the obtained light shielding portion 12 facing the lens array 13 is formed A light isolation and / or light scattering unit corresponding to the lens units of the lens array 13 one-to-one. Moreover, the light isolating and / or light scattering unit has a groove shape substantially corresponding to or matching the convex shape of the lens unit.

The wavelength conversion portion 11 and / or the blocking portion 12 undergo a volume shrinkage during the thermal curing or light curing process shown in FIG. 4 (e). Preferably, the material of the lens array 13 and the material of the wavelength conversion portion 11 and / or the blocking portion 12 are selected so that the expansion or contraction rate of the material of the lens array 13 is different from that of the wavelength conversion portion 11 and / or the blocking portion 12. Expansion or contraction. In this case, after curing, an air gap causing non-optical contact is formed between the wavelength conversion section 11 and / or the blocking section 12 and the lens array 13, so that each lens unit can function independently, and the wavelength conversion section 11 The emitted light is subjected to light shaping to obtain pixelated emitted light with a specific angular distribution.

According to the first embodiment, during the manufacturing process of the wavelength conversion element, the lens array functions as a mold, thereby greatly simplifying the difficulty of manufacturing the pixelated wavelength conversion element.

In addition, according to the first embodiment, during the preparation of the wavelength conversion element, by controlling the process parameters and material parameters so that there is an air gap at the surface of the lens array, the light shaping effect of the lens array itself can be exerted to the wavelength conversion material. The light undergoes light shaping to obtain pixelated outgoing light with a specific angular distribution.

Second embodiment

Compared with the wavelength conversion element of the first embodiment, the wavelength conversion element according to this embodiment is different in that, for a light-transmitting substrate, a prism array 23 is used instead of the lens array 13. The prism array 23 includes a plurality of prism units having prism-shaped protrusions. The prism array 23 can be directly obtained by using a mature prism film (BEF) manufacturing process. Other than that, the other configurations of the wavelength conversion element according to the second embodiment are the same as those of the wavelength conversion element according to the first embodiment.

Specifically, the wavelength conversion element according to the second embodiment includes a wavelength conversion section 21, a blocking section 22 for optically isolating and / or light scattering the wavelength conversion section 21, and a lens array 23 as a light-transmitting substrate. Similar to the first embodiment, the prism array 23 is disposed on the blocking portion 22, and the wavelength conversion portion 21 is interposed between the blocking portion 22 and the prism array 23.

Similar to the first embodiment, in this embodiment, the prism unit of the prism array 23 has a prism protrusion. However, the present invention is not limited to this. In the present invention, the shape of the prism unit of the prism array 23 may have any convex shape according to actual needs. The protrusion of the prism unit can play a role of mold and positioning during the preparation of the wavelength conversion element, thereby greatly simplifying the difficulty of preparing the pixelated wavelength conversion element.

Similar to the first embodiment, in this embodiment, the wavelength conversion portion 21 and the prism array 23 and / or the blocking portion 22 and the prism array 23 may be optical contact or non-optical contact. In the case of optical contact, the prism array 23 only functions as a support and a template. On the other hand, in the case of non-optical contact, the prism array can also play a role of light shaping the light emitted by the wavelength conversion section 21 at the same time. Preferably, the wavelength conversion portion 21 and the prism array 23 and / or the blocking portion 22 and the prism array 23 are in non-optical contact.

When the prism array 23 is in non-optical contact with the wavelength conversion portion 21 and the blocking material 22, an air gap causing non-optical contact is formed between the wavelength conversion portion 21 and / or the blocking portion 22 and the lens array 23, so that Each prism unit can function independently and perform light shaping on the light emitted by the wavelength conversion unit 21 to obtain pixelated emitted light with a specific angular distribution.

The method of manufacturing the wavelength conversion material according to the second embodiment is similar to the method of manufacturing the wavelength conversion element according to the first embodiment. The only difference between them is that the prism array 23 is used instead of the lens array 13 in the manufacturing process according to the second embodiment.

Similar to the first embodiment, according to the second embodiment, during the manufacturing process of the wavelength conversion element, the prism array plays a role of mold and positioning, thereby greatly simplifying the difficulty of manufacturing the pixelated wavelength conversion element.

In addition, similar to the first embodiment, according to the second embodiment, during the preparation of the wavelength conversion element, by controlling the process parameters and material parameters, there is an air gap at the surface of the prism array, which can play the role of light shaping of the prism array itself , Performing light shaping on the light emitted by the wavelength conversion material to obtain pixelated outgoing light with a specific angular distribution.

Although the light-transmitting substrate is described using the lens array 13 and the prism array 23 in the first and second embodiments of the present invention, the light-transmitting substrate of the present invention can also be used with Transparent substrate. The protrusion of the optical unit of the transparent substrate can play the role of mold and positioning during the preparation of the wavelength conversion element, thereby greatly simplifying the difficulty of preparing the pixelated wavelength conversion element.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the present invention is not limited thereto, and those skilled in the art should understand that without departing from the spirit or scope defined by the appended claims of the present invention, Make various changes, combinations, sub-combinations, and variations.

Claims

A wavelength conversion element includes:

A light-transmitting substrate, the light-transmitting substrate comprising a first optical unit with protrusions arranged in an array;

A barrier, the barrier includes a second optical unit with grooves arranged in an array, and the light-transmitting substrate is arranged on the barrier so that the first optical unit of the light-transmitting substrate and The second optical units of the blocking portion correspond one-to-one and face each other; and

A wavelength conversion section arranged at a top of the protrusion of the first optical unit of the light-transmitting substrate and a bottom of the groove of the second optical unit of the blocking section And interposed between the blocking portion and the transparent substrate.
The wavelength conversion element according to claim 1, wherein:

The light transmitting substrate is a lens array including a hemispherical lens unit as the first optical unit, or

The light-transmitting substrate is a prism array including a prism-shaped prism unit as the first optical unit.
The wavelength conversion element according to claim 1 or 2, wherein air is formed between the light-transmitting substrate and the blocking portion and / or between the light-transmitting substrate and the wavelength conversion portion. Gap.
The wavelength conversion element according to claim 1 or 2, wherein the blocking portion is formed by dispersing scattering particles in silica gel, light-curing glue, or glass and curing.
The wavelength converter of claim 4, wherein the element, wherein the scattering particles are TiO 2, Al 2 O 3, MgO, BaSO 4, one or more of.
The wavelength conversion element according to claim 1 or 2, wherein the wavelength conversion portion is formed by dispersing a light-emitting material in silica gel, photo-curing glue, or glass and curing it.
The wavelength conversion element according to claim 6, wherein the light emitting material is a rare earth phosphor or a quantum dot.
A method for preparing a wavelength conversion element includes:

In a first step, the luminescent material paste is coated on a flat substrate to form a luminescent material paste layer;

In a second step, a light-transmitting substrate including a first optical unit having protrusions arranged in an array is covered on the luminescent material paste layer so that at the top of the protrusion of the optical unit Adhered to the luminescent material paste;

In a third step, the light-transmitting substrate to which the luminescent material paste is adhered is removed, and the adhered luminescent material paste is pre-cured to form a pre-cured wavelength conversion portion; and

In a fourth step, a barrier portion including a second optical unit with grooves arranged on the structure is formed on the structure in the third step,

The fourth step is performed by one of the following methods:

(a) Inverting the structure obtained in the third step, coating the scattering particle slurry on the convex side of the light-transmitting substrate to form a scattering particle slurry layer, and curing the structure obtained at this time, thereby obtaining The wavelength conversion element including the light-transmitting substrate, the blocking portion, and the wavelength conversion portion; and

(b) coating the scattering particle slurry on another flat substrate to form a scattering particle slurry layer, covering the structure obtained in the third step on the scattering particle slurry layer, and applying the structure obtained at this time Curing, and removing the other flat substrate, thereby obtaining the wavelength conversion element including the light-transmitting substrate, the blocking portion, and the wavelength conversion portion.
The method according to claim 8, wherein:

The light transmitting substrate is a lens array including a hemispherical lens unit as the first optical unit, or

The light-transmitting substrate is a prism array including a prism-shaped prism unit as the first optical unit.
The method according to claim 8 or 9, wherein the second step to the third step are repeatedly performed two or more times so that the wavelength conversion section has a predetermined thickness.
The method according to claim 8 or 9, wherein the expansion or contraction rate of the material of the light-transmitting substrate is different from the expansion or contraction rate of the luminescent material slurry and / or the scattering particle slurry such that In the curing in the fourth step, an air gap is formed between the light-transmitting substrate and the blocking portion and / or between the light-transmitting substrate and the wavelength conversion portion.
The method according to claim 8 or 9, wherein the scattering particle slurry layer is formed by dispersing scattering particles in silica gel, light-curing glue, or glass.
The method of claim 12, wherein the scattering particles are TiO 2, Al 2 O 3, MgO, BaSO 4, one or more of.
The method according to claim 8 or 9, wherein the luminescent material paste layer is formed by dispersing a luminescent material in silica gel, photo-curing glue, or glass.
The method according to claim 14, wherein the light emitting material is a rare earth phosphor or a quantum dot.