A fluorescent element with a light guiding structure and a method for preparing the same

Abstract

The present invention discloses a fluorescent element with a light-guiding structure and a preparation method thereof. The fluorescent element comprises a fluorescent body, and the top surface of the fluorescent body has a light-guiding structure array. The light-guiding structure array is a plurality of grooves recessed downward from the top surface of the fluorescent body, and the grooves are also filled with fillers, and the refractive index of the fillers is greater than the refractive index of the fluorescent body. When laser is irradiated to the fluorescent element, the light enters the light-guiding structure array, and is internally totally reflected in the fillers in the grooves, producing an optical waveguide effect, being trapped therein, continuously exciting fluorescence, and dispersing energy. The light further enters the light-guiding sphere, and the refractive index of the light-guiding sphere is higher than that of the fluorescent body and the fillers, so the light irradiated therein can be internally totally reflected, trapped therein, dispersing the energy of the laser, and continuing to be internally totally reflected, and it is difficult to escape.

Description

Technical Field

[0001] The present invention relates to the field of lighting and display technology, and in particular to a fluorescent element with a light guiding structure and a preparation method thereof. Background Art

[0002] Compared with traditional LEDs, laser diode lighting has higher lumen efficiency, better light color uniformity, and more accurate directionality, and is widely used in car lights, lighting for cultural relics protection units, and display fields. However, due to the high energy density of the laser, it is easy to cause heat concentration on the surface of the fluorescent component, and the incident light is difficult to excite the internal fluorescent material, causing the surface of the fluorescent component to carbonize and fail, and also sharply reducing the fluorescence conversion efficiency of the phosphor. In order to solve this problem, many products currently use heat pipes and heat sinks to dissipate heat, but the thermal resistance of the fluorescent component itself is high, and it is difficult to transfer the heat directly facing the laser light source to the heat pipe and heat sink. The effect is not very ideal, and this method does not solve the problem of fluorescence conversion efficiency. Summary of the invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a fluorescent element with a light guiding structure, which solves the problems of heat concentration on the surface of the prior fluorescent element and low conversion efficiency.

[0004] Another object of the present invention is to provide a method for preparing the fluorescent element with the light guiding structure.

[0005] The technical solution of the present invention is: a fluorescent element with a light-guiding structure, including a fluorescent body, the top surface of the fluorescent body having a light-guiding structure array, the light-guiding structure array being a plurality of grooves recessed downward from the top surface of the fluorescent body, the grooves also being filled with a filler, and the refractive index of the filler is greater than the refractive index of the fluorescent body.

[0006] Furthermore, the filling amount of the filler is 10%-100% of the groove depth, and the material of the filler is glass, silica gel or epoxy resin.

[0007] Furthermore, the depth of the groove is 10%-90% of the thickness of the fluorescent body, and the aperture of the groove is less than 100 μm.

[0008] Furthermore, the material of the fluorescent body is polydimethylsiloxane or organic silica gel.

[0009] Furthermore, it also includes a light guiding sphere, the bottom of the groove is provided with a light guiding sphere, and the refractive index of the light guiding sphere is greater than the refractive index of the filler.

[0010] Furthermore, the radius of the light-guiding sphere is 50%-150% of the radius of the groove, and the material of the light-guiding sphere is glass, plastic or polymethyl methacrylate.

[0011] Furthermore, the depth distribution of the plurality of grooves in the light guiding structure array is deep in the middle and shallow on both sides.

[0012] Another technical solution of the present invention is: a method for preparing the fluorescent element with a light guiding structure, comprising the following steps:

[0013] Step S1: Select a mold with array needles on it, add polydimethylsiloxane or organic silica gel into the mold, and mix the phosphor into it;

[0014] Step S2: heating and curing once, the temperature is 50-300 degrees Celsius, the heating time is 0.5-3.0 hours, and after curing, the mold is pulled out to obtain a fluorescent body, and the upper light guiding structure array of the fluorescent body is formed by taking out the array needles on the mold;

[0015] Step S3: adding fillers into the light guiding structure array;

[0016] Step S4: secondary heating and curing, the temperature is 50-300 degrees Celsius, the heating time is 0.5-3.0 hours, and after curing, it is taken out for quality inspection.

[0017] Furthermore, after the fluorescent body is obtained in step S2, light guiding spheres are pressed into the light guiding structure array.

[0018] Furthermore, the material of the phosphor is yttrium aluminum garnet or nitride phosphor, and the mass ratio of the phosphor to polydimethylsiloxane or organic silica gel is 1:1-1:10.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The fluorescent element with a light-guiding structure of the present invention, when the laser irradiates the fluorescent element, the light enters the light-guiding structure array, undergoes total internal reflection in the filler in the groove, produces an optical waveguide effect, is trapped therein, continuously excites fluorescence, disperses energy, and the light further enters the light-guiding sphere. The refractive index of the light-guiding sphere is higher than that of the fluorescent body and the filler, so the light incident therein can undergo total internal reflection, is trapped therein, disperses the energy of the laser, continues to undergo total internal reflection, and is difficult to escape, thereby improving the fluorescence conversion efficiency, reducing heat concentration, and having high reliability, and is very suitable for application environments such as high-power laser car lights. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the structure of the fluorescent element in Example 1 of the present invention.

[0022] Figure 2 It is a top view of the fluorescent element in Example 1 of the present invention.

[0023] Figure 3 for Figure 2 Cross-sectional view along line DD.

[0024] Figure 4 This is a diagram of the light guiding principle in Example 1 of the present invention.

[0025] Figure 5 This is a schematic diagram of the mold structure in Example 1 of the present invention.

[0026] Figure 6 It is a top view of the fluorescent element in Example 2 of the present invention.

[0027] Figure 7 for Figure 6 Section view along line AA.

[0028] Figure 8 This is a diagram of the light guiding principle in Example 2 of the present invention.

[0029] Fig. 9 Schematic diagram of the structure of the fluorescent element in Example 3 of the present invention.

[0030] Fig.10 FIG. 4 is another schematic diagram of the structure of the fluorescent element in Example 3 of the present invention.

[0031] Fig.11 Schematic diagram of the structure of the fluorescent element in Example 4 of the present invention.

[0032] Fig.12 This is a schematic diagram of the mold structure in Example 4 of the present invention.

[0033] Fig.13 It is a top view of the fluorescent element in Example 5 of the present invention.

[0034] Fig.14 for Fig.13 Section view along line BB.

[0035] Fig.15 Schematic diagram of the structure of the fluorescent element in Example 6 of the present invention.

[0036] Fig.16 This is a schematic diagram of the mold structure in Example 6 of the present invention.

[0037] Fig.17 Schematic diagram of the structure of the fluorescent element in Example 7 of the present invention.

[0038] Fluorescent body 1, groove 2, light guiding sphere 3, filler 4, mold 5, array needle 6. DETAILED DESCRIPTION

[0039] The present invention will be further described in detail below in conjunction with examples, but the embodiments of the present invention are not limited thereto.

[0040] Example 1

[0041] This embodiment provides a fluorescent element with a light guiding structure, including a fluorescent body.

[0042] like Figure 1 , Figure 2 and Figure 3 As shown, the fluorescent body 1 is disc-shaped, with a thickness of 0.5mm-50mm and a radius of 10mm-100mm. The material of the fluorescent body is polydimethylsiloxane. In other embodiments, the material of the fluorescent body may be organic silicone with a trade name of OE6650. The top surface of the fluorescent body has a light guiding structure array. The light guiding structure array is a plurality of grooves 2 recessed downward from the top surface of the fluorescent body. The depth of the groove is 10%-90% of the thickness of the fluorescent body. The aperture of the groove is less than 100μm. The groove is filled with a filler 4. The material of the filler is glass, silicone or epoxy resin. The filling amount of the filler is 10%-100% of the depth of the groove. The refractive index of the filler is greater than the refractive index of the fluorescent body.

[0043] The method for preparing the fluorescent element having the light guiding structure comprises the following steps:

[0044] Step S1: Select a mold 5, on which an array needle 6 is provided, add polydimethylsiloxane into the mold, and mix phosphor into the mold, wherein the mass ratio of phosphor to polydimethylsiloxane is 1:1, and the material of the phosphor is yttrium aluminum garnet. In other embodiments, the phosphor may be nitride phosphor;

[0045] Step S2: heating and curing once, the temperature is 300 degrees Celsius, the heating time is 0.5 hours, and after curing, the mold is pulled out to obtain a fluorescent body, and the upper light guiding structure array of the fluorescent body is formed by taking out the array needles on the mold;

[0046] Step S3: adding fillers into the light guiding structure array;

[0047] Step S4: secondary heating and curing, the temperature is 300 degrees Celsius, the heating time is 0.5 hours, and after curing, it is taken out for quality inspection.

[0048] like Figure 1 and Figure 5 As shown, the shape of the fluorescent body is the same as that of the mold, both are disc-shaped, the cross-sectional shape of the groove is circular, the light guiding structure array is distributed in a rectangular shape, and the array needles on the mold are steel needle arrays, the shape of the array needles is circular, and the distribution of the array needles is rectangular.

[0049] like Figure 4 As shown, when the laser hits the fluorescent element, the light enters the light guiding structure array, undergoes total internal reflection in the filling in the groove, produces a light waveguide effect, is trapped inside, continuously stimulates fluorescence, and disperses energy.

[0050] Example 2

[0051] The difference between this embodiment and embodiment 1 is that it further includes a light guiding sphere.

[0052] like Figure 6 and Figure 7 As shown, a light guiding sphere 3 is provided at the bottom of the groove, the refractive index of the light guiding sphere is greater than the refractive index of the filler, the radius of the light guiding sphere is 50%-150% of the radius of the groove, and the material of the light guiding sphere is glass, plastic or polymethyl methacrylate.

[0053] The method for preparing the fluorescent element having the light guiding structure comprises the following steps:

[0054] Step S1: Select a mold 5, on which an array needle 6 is provided, add polydimethylsiloxane into the mold, and mix phosphor into the mold, wherein the mass ratio of phosphor to polydimethylsiloxane is 1:1, and the material of the phosphor is yttrium aluminum garnet. In other embodiments, the phosphor may be nitride phosphor;

[0055] Step S2: heating and curing once, the temperature is 300 degrees Celsius, the heating time is 0.5 hours, and after curing, the mold is pulled out to obtain a fluorescent body, and the upper light guiding structure array of the fluorescent body is formed by taking out the array needles on the mold;

[0056] Step S3: Pressing light-guiding spheres into the light-guiding structure array;

[0057] Step S4: adding fillers into the light guiding structure array;

[0058] Step S5: Secondary heating and curing, the temperature is 300 degrees Celsius, the heating time is 0.5 hours, and after curing, it is taken out for quality inspection.

[0059] like Figure 5 and Figure 6 As shown, the shape of the fluorescent body is the same as that of the mold, both are disc-shaped, the cross-sectional shape of the groove is circular, the light guiding structure array is distributed in a rectangular shape, and the array needles on the mold are steel needle arrays, the shape of the array needles is circular, and the distribution of the array needles is rectangular.

[0060] like Figure 8As shown, when the laser hits the fluorescent element, the light enters the light guiding structure array, undergoes total internal reflection in the filler in the groove, produces an optical waveguide effect, is trapped therein, continuously excites fluorescence, disperses energy, and the light further enters the light guiding sphere. The refractive index of the light guiding sphere is higher than that of the fluorescent body and the filler, so the light entering therein can undergo total internal reflection, is trapped therein, disperses the energy of the laser, continues to undergo total internal reflection, and is difficult to escape.

[0061] Example 3

[0062] The difference between this embodiment and embodiment 1 is that the cross-sectional shape of the groove is a triangle (such as Fig. 9 as shown) or a rectangle (as Fig.10 As shown), the light-guiding structure array is distributed in a rectangular shape, and is cured by heating once at a temperature of 50 degrees Celsius for 3.0 hours. It is cured by heating twice at a temperature of 50 degrees Celsius for 3.0 hours. The mass ratio of the phosphor to polydimethylsiloxane is 1:10.

[0063] Example 4

[0064] The difference between this embodiment and embodiment 1 is that Fig.11 and Fig.12 As shown, the shape of the fluorescent body and the mold are both disc-shaped, and the light-guiding structure array is distributed in a circle; the first heating curing is at a temperature of 150 degrees Celsius and a heating time of 1.5 hours, and the second heating curing is at a temperature of 150 degrees Celsius and a heating time of 1.5 hours. The mass ratio of the fluorescent powder to polydimethylsiloxane is 1:5.

[0065] Example 5

[0066] The difference between this embodiment and embodiment 1 is that Fig.13 and Fig.14 As shown, the depth distribution of the multiple grooves in the light guiding structure array is deep in the middle and shallow on both sides, which conforms to the light spot energy distribution and can better disperse the energy of the incident light.

[0067] Example 6

[0068] The difference between this embodiment and embodiment 1 is that Fig.15 and Fig.16 As shown, the shape of the fluorescent body and the shape of the mold are hemispherical, the radius of the fluorescent body is between 10 mm and 100 mm, the light guiding structure array is annularly distributed, and the groove depth is 10%-70% of the radius of the fluorescent body.

[0069] Example 7

[0070] The difference between this embodiment and embodiment 1 is that Fig.17As shown, the shape of the fluorescent body and the shape of the mold are square, the length, width and height of the fluorescent body are all between 10mm and 100mm, and the light guiding structure array is distributed in a rectangular shape, and its depth is 10%-90% of the height of the fluorescent body.

[0071] As described above, the present invention can be better implemented. The above embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention; that is, all equivalent changes and modifications made according to the content of the present invention are covered by the scope of protection required by the claims of the present invention.

Claims

1. A fluorescent element with a light guiding structure, characterized in that: The fluorescent body comprises a light guiding structure array on the top surface of the fluorescent body, wherein the light guiding structure array is a plurality of grooves recessed downward from the top surface of the fluorescent body, and the grooves are filled with a filler, and the refractive index of the filler is greater than the refractive index of the fluorescent body; A method for preparing a fluorescent element having a light guiding structure comprises the following steps: Step S1: Select a mold with array needles on it, add polydimethylsiloxane or organic silica gel into the mold, and mix the phosphor into it; Step S2: heating and curing once, the temperature is 50-300 degrees Celsius, the heating time is 0.5-3.0 hours, and after curing, the mold is pulled out to obtain a fluorescent body, and the upper light guiding structure array of the fluorescent body is formed by taking out the array needles on the mold; Step S3: adding fillers into the light guiding structure array; Step S4: secondary heating and curing, the temperature is 50-300 degrees Celsius, the heating time is 0.5-3.0 hours, and after curing, it is taken out for quality inspection.

2. The fluorescent element with a light guiding structure according to claim 1, characterized in that: The filling amount of the filler is 10%-100% of the groove depth, and the material of the filler is glass, silica gel or epoxy resin.

3. The fluorescent element with a light guiding structure according to claim 1, characterized in that: The depth of the groove is 10%-90% of the thickness of the fluorescent body, and the aperture of the groove is less than 100 μm.

4. The fluorescent element with a light guiding structure according to claim 1, characterized in that: It also includes a light guiding sphere. The bottom of the groove is provided with the light guiding sphere, and the refractive index of the light guiding sphere is greater than the refractive index of the filler.

5. The fluorescent element with a light guiding structure according to claim 4, characterized in that: The radius of the light-guiding sphere is 50%-150% of the radius of the groove, and the material of the light-guiding sphere is glass, plastic or polymethyl methacrylate.

6. The fluorescent element with a light guiding structure according to claim 1, characterized in that: The depth distribution of the plurality of grooves in the light guiding structure array is deep in the middle and shallow on both sides.

7. The fluorescent element with a light guiding structure according to claim 1, characterized in that: After the fluorescent body is obtained in step S2, light guiding spheres are pressed into the light guiding structure array.

8. The fluorescent element with a light guiding structure according to claim 1, characterized in that: The material of the phosphor is yttrium aluminum garnet or nitride phosphor, and the mass ratio of the phosphor to polydimethylsiloxane or organic silica gel is 1:1-1:10.

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