Abstract
The invention relates to a light emitting device (LED), especially a LED at least partly embedded in transparent or translucent silicone fill, whereby the embedded LED is housed in a white silicone housing. Here and in the following, the wording transparent silicone fill always means a transparent or translucent silicone material. The invention further relates to a method for embedding the LED partly in a white silicone housing on the one hand and partly in transparent silicone fill on the other hand. The invention finally relates to the transparent silicone fill. The inner part of the LED device is at least partly embedded in transparent silicone fill, wherein the at least partly embedded LED device is housed in a white silicone housing comprising a white box silicone. A part of the inner part of the LED device is embedded in the white box silicone.
Claims
1. A light emitting diode (LED) device comprising: an inner part of the LED device, the inner part including at least a contact device and an LED chip, at least partly embedded in a white silicone housing, such that each of the contact device and the LED chip are at least partially embedded in the white silicone.
2. The LED device of claim 1, further comprising a transparent silicone fill at least partially embedding the LED chip.
3. The LED device of claim 1, the inner part of the LED device further comprising an interposer at least partially embedded in the white silicone.
4. The LED device of claim 3, further comprising a transparent silicone fill at least partially embedding the interposer.
5. The LED device of claim 1, further comprising a transparent silicone fill at least partially embedding the LED chip.
6. The LED device of claim 4, further comprising a diffuser adjacent to the transparent silicone fill.
7. A method for producing a light emitting diode (LED) device, the method comprising: producing a housing including a cavity formed from white silicone; at least partially filling the cavity with an additional white silicone; placing an inner part of the LED device including a contact device and an LED chip in the cavity encasing at least the contact device in the additional white silcone; and filling the remainder of the cavity with a transparent silicone fill.
8. The method of claim 7, further comprising curing the additional white silicone.
9. The method of claim 7, further comprising positioning a diffusor adjacent to the transparent silicone fill.
10. The method of claim 9, wherein the diffuser is configured to diffuse emitted LED light and is applied to a side of the LED device distal to the contact device.
11. The method of claim 9 wherein the diffuser is formed from silicone.
12. The method of claim 9, further comprising curing the transparent silicone fill.
13. The method of claim 7, further comprising, in parallel, curing the transparent silicone fill and the additional white silicone.
14. The method of claim 7, wherein the at least partially filling the cavity with additional white silicone includes an amount of additional white silicone to partially encase the contact device.
15. The method of claim 7, further comprising at least partially encasing an interposer in the additional white silicone.
16. The method of claim 15, wherein the at least partially filling the cavity with additional white silicone includes an amount of additional white silicone to partially encase the interposer.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0042] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.
[0043] The invention will now be described, by way of example, based on embodiments with reference to the accompanying drawings.
[0044] In the drawings:
[0045] FIG. 1 shows a principal sketch of a LED device having an LED package, an interposer and a contact device embedded in transparent silicone fill in a housing of white silicone as it is known in the state of the art.
[0046] FIG. 2 shows a principal sketch of a LED device having an LED package, an interposer and a contact device embedded partially in transparent silicone fill after a first step of the method according to the invention.
[0047] FIG. 3 shows a principal sketch of a LED device having an LED package, an interposer, a contact device and a diffusor embedded partially in transparent silicone fill after a second step of the method according to an embodiment of the invention.
[0048] FIG. 4 shows a principal sketch of a LED device having an LED package, an interposer, a contact device and a diffusor embedded partially in transparent silicone fill and encased with white silicone after a third step of the method according to an embodiment of the invention.
[0049] FIG. 5 shows a principal sketch of a LED device having an LED package, an interposer, a contact device and a diffusor embedded partially in transparent silicone fill and encased with white silicone after a third step of the method according to a further embodiment of the invention.
[0050] FIG. 6 shows a principal sketch of a LED device having an LED package, an interposer, a contact device and a diffusor embedded partially in transparent silicone fill and encased with white silicone after a third step of the method according to a further embodiment of the invention.
[0051] FIG. 7 shows a principal sketch of a housing of white silicone according to the alternative method.
[0052] FIG. 8 shows a principal sketch of the housing of white silicone with additionally filled in white silicone according to the alternative method.
[0053] FIG. 9 shows a principal sketch of a LED device having an LED package, an interposer, a contact device embedded partially in the additionally filled in with white silicone, according to the alternative method.
[0054] FIG. 10 shows a principal sketch of a LED device having an LED package, an interposer, a contact device and a diffusor embedded partially in the additionally filled in with white silicone with transparent silicone fill filled in the cavity according to the alternative method.
[0055] FIG. 11 shows a principal sketch of a LED device having an LED package, an interposer, a contact device and a diffusor embedded partially in the additionally filled in with white silicone with transparent silicone fill filled in the cavity with a diffusor attached to the transparent silicone fill, according to the alternative method.
[0056] In the Figures, like numbers refer to like objects throughout. Objects in the Figs. are not necessarily drawn to scale.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0057] Various embodiments of the invention will now be described by means of the Figures.
[0058] FIG. 1 shows a principal sketch of a LED device having an LED package 1, an interposer 2 and a contact device 3 embedded in transparent silicone fill 4 in a housing 6 of white silicone as it is known in the state of the art. This LED device is produced by starting with the housing, which is made for instance by extrusion. In this housing 6 the inner part of a LED device comprising the LED package 1, the interposer 2 and the contact device 3 comprising inner part wires are put in. In a next step, the transparent silicone is filled in the housing 6, whereby the transparent silicone encloses the inner part of the LED device comprising the LED package 1, the possible interposer 2 and a contact device 3 comprising inner part wires. In service, parts of emitted light is lost by absorption on the inner part, especially the light travelling around and below the interposer 2. In addition the heat transport from the LED package is not optimal seen the fact that the transparent silicone fill 4 only has one fifth of the thermal conductivity as compared to the white silicone.
[0059] FIG. 2 shows a principal sketch of a LED device having an LED package 1, an interposer 2 and a contact device 3 embedded partially in transparent silicone fill 4 after a first step of the method according to the invention. In this first step, the inner part of the LED device is encased at least partially with transparent silicone fill 4. In the embodiment shown, the LED package and the interposer 2 are encased in the transparent silicone fill 4. The contact device 3 is left open from the transparent silicone fill 4. The outer edges of the transparent silicone fill thereby are to be defined by the housing applied in a further step. Therefore in the figure, the outer edges are cut off. The transparent silicone fill 4 may be applied by any known method, such as for instance transfer molding or injection molding, FIG. 3 shows a principal sketch of a LED device having an LED package 1, an interposer 2, a contact device 3 and a diffusor 5 embedded partially in transparent silicone fill 4 after a second step of the method according to an embodiment of the invention. In this second step, the diffusor 5 is applied to the transparent silicone fill 4. The outer edges of the transparent silicone fill thereby are to be defined by the housing applied in a further step. Therefore in the figure, the outer edges are cut off. The diffusor 5 may be preprocessed and applied to the transparent silicone fill 4. In other embodiments, the diffusor 5 may be applied to the silicone fill by known silicone processing methods such as transfer molding or injections molding, e.g.. The step also may be omitted in case, no diffusor 5 is used with the LED device. Moreover, the step of applying the diffusor 5 may also be done after the step described in FIG. 4.
[0060] FIG. 4 shows a principal sketch of a LED device having an LED package 1, an interposer 2, a contact device 3 and a diffusor 5 embedded partially in transparent silicone fill 4 and encased with white silicone after a third step of the method according to an embodiment of the invention. Since the contact device 3 was left open from the transparent silicone fill 4, in the third step this contact device is encased in the white silicone of the housing 6. The white silicone forming the housing 6 may be applied by injection molding, i.e. by overmolding the transparent silicone fill, e.g. the top of the LED device, i.e. the side of the LED device opposite the contact device 3, is left open from overmolding with the white silicone. That is to say that the light emitted from the LED package 1 may run through the diffusor 5 and leave the LED device. As already explained in accordance to FIG. 3, in another embodiment the LED device has no diffusor 5. In this case the light emitted by the LED package 1 may leave the LED device via the top side of the LED device, i.e. the transparent silicone fill 4. Moreover, the step of applying the diffusor 5 may also be done after applying the white silicone. In this case the white silicone may only be applied until the top of the transparent silicone fill 4 or beyond the top of the transparent silicone fill when a gap is left in which the diffusor 5 may be applied afterwards.
[0061] FIG. 5 shows a principal sketch of a LED device having an LED package 1, an interposer 2, a contact device 3 and a diffusor 5 embedded partially in transparent silicone fill 4 and encased with white silicone after a third step of the method according to an further embodiment of the invention. In this embodiment, in the step when the transparent silicone fill 4 is applied, additionally to the contact device 3 the interposer 2 is left open from the transparent silicone fill 4 as well. In the step when the white silicone box is applied, the contact device 3 as well as the interposer 2 is clasped with the white silicone. Accordingly, only the LED package 1 is left open from the box made of white silicone.
[0062] FIG. 6 shows a principal sketch of a LED device having an LED package 1 , an interposer 2 , a contact device 3 and a diffusor 5 embedded partially in transparent silicone fill 4 and encased with white silicone after a third step of the method according to an further embodiment of the invention. In this embodiment, in the step when the transparent silicone fill 4 is applied, additionally to the contact device 3 and the interposer 2, the LED package 1 is partly left open from the transparent silicone fill 4. In the step when the white silicone box is applied, the contact device 3, the interposer 2 and a part of the LED package 1 is clasped with the white silicone. Accordingly, only a part the LED package 1 is left open from the white silicone, especially the top, i.e. the side opposite of the contact device 3, of the LED package 1 is left open from the white silicone. Light emitted by the LED package 1 may leave the LED device.
[0063] FIG. 7 shows a principal sketch of a housing 6 made of white silicone as used in the alternative method. The housing 6 comprises a cavity 7 in which a LED device can be placed. The housing 6 is made of white silicone, which reflects the light. An LED device placed in such housing 6 is able to emit the light through the opening at the top side of the housing 6 only. The housing 6 may be produced for instance by extruding or injection molding, Methods for producing such housings 6 are known by those skilled in the art.
[0064] FIG. 8 shows a principal sketch of the housing 6 of white silicone with additionally filled in white silicone 8, according to the alternative method. The additional white silicone 8 fills the cavity only partially. The additionally filled in white silicone 8 may be a different material as the white silicone of the housing 6. In another embodiment, the additionally filled in white silicone 8 may be the same material as the white silicone of the housing 6. Filling in the additional filled in white silicone 8 can be done by dispending the material for instance in its fluid state.
[0065] FIG. 9 shows a principal sketch of a LED device having an LED package 1, an interposer 2 and a contact device 3 embedded partially in the additionally filled in with a box of white silicone 8, according to the alternative method. Since the additionally filled in silicone 8 is in fluid state, the inner part of the LED device dives in this material easily. The inner part of the LED device dives in the additionally filled in white silicone 8 until it touches the bottom of the housing 6, which is cured white silicone. Thereby the amount of the additionally filled in with white silicone 8 is calculated in that way that the inner part of the LED device dives in only partially, i.e. only at least partially with the contact device 3 or with the contact device 3 and at least partially the interposer 2 or with the contact device3, the interposer 2 and partially with the LED package 1. Thereby, the top side of the LED package 1, i.e. the side opposite of the contact device 3, is left out of the additionally filled in with white silicone 8. Therewith light emitted from the LED package 1 my leave the LED device at this top side.
[0066] FIG. 10 shows a principal sketch of a LED device having an LED package 1, an interposer 2, a contact device 3 and a diffusor 5 embedded partially in the additionally filled in with white silicone 8 with transparent silicone fill 4 filled in the cavity 8, according to the alternative method. After placing the inner part of the LED device in the additionally filled in with white silicone 8 in the cavity 7, the additionally filled in with white silicone 8 may be cured. In another embodiment, the additionally filled in with white silicone 8 is not cured at this stage. It may be cured in parallel with the transparent silicone fill 4 filled in in a later step. In any case after placing the inner part of the LED device in the additionally filled in with white silicone 8 in the cavity 7, the cavity 7 is filled with transparent silicone fill 4. Thereby the cavity 7 may be filled totally or only in a rate that a diffusor 5 may be placed on top of the transparent silicone fill 4. Thereby the diffusor 5 can be placed on top of the transparent silicone fill 4 in that way that it is at least partly enclosed from the housing 6.
[0067] FIG. 11 shows a principal sketch of a LED device having an LED package 1, an interposer 2, a contact device 3 and a diffusor 5 embedded partially in the additionally filled in with white silicone with transparent silicone fill 4 filled in the cavity 7 with a diffusor 5 attached to the transparent silicone fill 4, according to the alternative method. The diffusor 5 is attached to the top side of the transparent silicone fill 4 in that way that its small sides are enclosed from the housing 6 and the top side is open to the environment. Accordingly, only a part the LED package 1 is left open from the white silicone, especially the top, i.e. the side opposite of the contact device 3, of the LED package 1 is left open from the white silicone. Light emitted by the LED package 1 may leave the LED device through this area. In putting parts of the inner part of the LED device in the white silicone prevent the lost of light emitted by the LED package 1 by absorption on the inner part of the LED device. The light does not reach these parts of the LED device since these parts are enclosed in reflecting the white silicone. Moreover, heat transport from the LED package 1 to the environment is optimized since the white silicone has a thermal conductivity which is five times as big as that of the transparent silicone 4.
[0068] While the invention has been illustrated and described in detail in the drawings and the foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive.
[0069] From reading the present disclosure, other modifications will be apparent to persons skilled in the art. Such modifications may involve other features which are already known in the art and which may be used instead of or in addition to features already described herein.
[0070] Variations to the disclosed embodiments can be understood and effected by those skilled in the art, from a study of the drawings, the disclosure and the appended claims In the claims, the word “comprising” does not exclude other elements or steps, and the indefinite article “a” or “an” does not exclude a plurality of elements or steps. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.
[0071] Any reference signs in the claims should not be construed as limiting the scope thereof.
REFERENCE SIGNS
[0072] 1 LED package
[0073] 2 Interposer
[0074] 3 Contact device
[0075] 4 Silicone fill
[0076] 5 Diffusor
[0077] 6 Housing
[0078] 7 Cavity
[0079] 8 Additional filled in white silicone
