LIGHT-EMITTING DIODE INCLUDING A PLURALITY OF LUMINESCENT REGIONS

Abstract

Various embodiments may relate to A light-emitting diode, including an LED chip having at least one emitter surface for emitting primary light, and a plurality of luminescent regions, which are connected optically downstream from the at least one emitter surface. At least one harder one of the luminescent regions is embedded in another, softer one of the luminescent regions.

Claims

1. A light-emitting diode, comprising: an LED chip comprising at least one emitter surface for emitting primary light, and a plurality of luminescent regions, which are connected optically downstream from the at least one emitter surface, wherein a first luminescent region of the luminescent regions is embedded in a second luminescent region of the luminescent regions; wherein the first luminescent region comprises a harder base material as compared to a base material of the second luminescent region; and wherein the first luminescent region and the second luminescent region contact a front side of the LED.

2. The light-emitting diode as claimed in claim 1, wherein the first luminescent regions consists of ceramic.

3. The light-emitting diode as claimed claim 1, wherein the base material of the second luminescent region comprises a matrix material made of plastic, which is admixed with at least one phosphor as a filler material.

4. The light-emitting diode as claimed in claim 1, wherein the luminescent regions are arranged adjacent to one another in a light path of the primary light.

5. The light-emitting diode as claimed in claim 4, wherein the luminescent regions represent regions of a luminescent lamina and cover an emitter surface of the LED chip.

6. The light-emitting diode as claimed in claim 5, wherein the first luminescent region is laterally enclosed by the second luminescent region.

7. The light-emitting diode as claimed in claim 1, wherein the first luminescent region has the basic form of a circular disk.

8. The light-emitting diode as claimed in claim 1, wherein the primary light is blue light, the first luminescent region converts the blue primary light at least partially into green to yellow light and the second luminescent region converts the blue primary light at least partially into red light.

9. The light-emitting diode as claimed in claim 1, wherein the second luminescent region has been produced by a printing method.

10. The light-emitting diode according to claim 1, wherein the second luminescent region has been produced by a casting method.

11. The light-emitting diode according to claim 1, wherein the first luminescent region is disposed on a middle of the front side of the LED.

12. The light-emitting diode according to claim 11, wherein the second luminescent region is laterally disposed around the first luminescent region.

13. The light-emitting diode according to claim 12, wherein the first luminescent region is substantially circular.

14. The light-emitting diode according to claim 1, wherein the first luminescent region and the second luminescent region are substantially the same height.

15. The light-emitting diode according to claim 1, wherein the first luminescent region contacts the second luminescent region.

16. The light-emitting diode according to claim 1, wherein the base material of the first luminescent region comprises ceramic.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In the drawings, like reference characters generally refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the disclosed embodiments. In the following description, various embodiments described with reference to the following drawings, in which:

[0027] FIG. 1 shows a sectional illustration in a side view of a light-emitting diode according to various embodiments;

[0028] FIG. 2 shows the light-emitting diode according to various embodiments in a top view; and

[0029] FIGS. 3A-3B show a sequence of a first method for producing a luminescent lamina of the light-emitting diode according to various embodiments; and

[0030] FIG. 4 shows a sequence of a second method for producing a luminescent lamina of the light-emitting diode according to various embodiments.

DETAILED DESCRIPTION

[0031] The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and aspects of this disclosure in which the invention may be practiced.

[0032] FIG. 1 shows a sectional illustration in a side view of a light-emitting diode 11 having an LED chip 12, which has a rear support surface 13 and a front side 14 having an emitter surface 15, which emits primary light forward or upward (top LED). The LED chip 12 thus emits into a front half-space. The primary light may be blue light, for example.

[0033] A luminescent lamina 16, which completely covers the emitter surface 15, rests on the front side 14. As is also apparent in a top view from FIG. 2, the luminescent lamina 16 has two luminescent regions, namely a circular first luminescent region 17 made of ceramic phosphor and a second luminescent region 18 made of plastic matrix material, in particular silicone, filled with phosphor powder. The two luminescent regions 17 and 18 have an at least essentially equal height. The first (harder) luminescent region 17 is arranged in the middle in relation to a longitudinal axis L of the light-emitting diode 11, while the second (softer) luminescent region 18 laterally encloses the first luminescent region 17. The first luminescent region 17 is therefore laterally embedded in the second luminescent region 18.

[0034] In operation of the LED chip 12, primary light emitted from the emitter surface 15 is radiated both into the first luminescent region 17 and converted therein, for example, at least partially into green light and also radiated into the second luminescent region 18 and converted therein, for example, at least partially into red light. The luminescent regions 17, 18 are thus connected optically downstream from the emitter surface 15 and arranged adjacent to one another in a light path of the primary light. A red-green-blue or warm white mixed light is thus emitted overall at high efficiency from the luminescent lamina 16. Due to the lateral separation of the luminescent regions 17, 18, the mutual influence thereof is kept low.

[0035] FIG. 3A shows a step of a first method for producing the luminescent lamina 16 by a printing method. In this step, a plurality of prefinished first luminescent regions 17 in the form of luminescent ceramic laminae in the shape of circular disks are placed in a mask 19.

[0036] In a following step, the mask 19 having the first luminescent regions 17 located therein is printed, specifically using the still viscous material of the second luminescent region 18. The material of the second luminescent region 18 is thus filled in the free lateral intermediate spaces between the mask 19 and the first luminescent regions 17.

[0037] After curing of the material of the second luminescent region 18, the mask 19 is removed, whereby the finished luminescent laminae 16 are isolated, as shown in FIG. 3B.

[0038] The luminescent laminae 16 can thereafter be applied to the LED chip 12, for example, glued on.

[0039] FIG. 4 shows a step of a second method for producing the luminescent lamina 16, specifically by a casting method.

[0040] During the casting method, the first luminescent region 17 is placed in a casting mold 19 and then embedded using the material of the second luminescent region 18, here: up to an upper edge of the first luminescent region 17, but not covering the emitter surface 15.

[0041] While the disclosed embodiments have been particularly shown and described with reference to specific embodiments, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the disclosed embodiments as defined by the appended claims. The scope of the disclosed embodiments is thus indicated by the appended claims and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced.

LIST OF REFERENCE SIGNS

[0042] 11 light-emitting diode [0043] 12 LED chip [0044] 13 rear support surface [0045] 14 front side [0046] 15 emitter surface [0047] 16 luminescent lamina [0048] 17 first luminescent region [0049] 18 second luminescent region [0050] 19 mask [0051] 20 casting mold [0052] L longitudinal axis