Hermetically sealed LED light and method for manufacturing a hermetically sealed LED light

Abstract

A hermetically sealed LED light is provided that includes a ceramic base with a plurality of LEDs and a metal cap soldered thereto and a channel for introducing an electrical, optical, or mechanical component.

Claims

1. A hermetically sealed LED light, comprising: a base made of ceramic with a plurality of LEDs thereon; a metal cap having a channel for each of the plurality of LED's extending therethrough, each of the channels having an upper end and a lower end, the metal cap being soldered to the base by a gold-tin solder; a plurality of glass windows hermetically sealed to the metal cap at the upper end of each of the channels, the plurality of windows having a lenticular shape that does not protrude from the metal cap in the axial direction of the channel; and a component channel extending through the base and through the metal cap, for introducing an electrical, optical, or mechanical component.

2. The hermetically sealed LED light as claimed claim 1, comprising an annular shape, the component channel being centrally arranged.

3. The hermetically sealed LED light as claimed in claim 1, wherein the plurality of windows are annularly distributed.

4. The hermetically sealed LED light as claimed in claim 1, wherein the plurality of windows each comprise a lens.

5. The hermetically sealed LED light as claimed in claim 4, wherein the lens of the plurality of windows have a different focal length and/or a different aperture angle.

6. The hermetically sealed LED light as claimed in claim 1, further comprising a converter arranged in each of the channels below the plurality of windows.

7. The hermetically sealed LED light as claimed in claim 1, wherein the metal cap has a depression adjacent to each of the plurality of windows.

8. The hermetically sealed LED light as claimed in claim 1, wherein the plurality of LEDs comprise separately controllable LEDs of different light color.

9. The hermetically sealed LED light as claimed in claim 8, wherein the at least two of the separately controllable LEDs have a different light emission angle.

10. The hermetically sealed LED light as claimed in claim 1, further comprising a medical instrument having the hermetically sealed LED light embedded therein so that LED light directly radiates from the plurality of LEDs to outside of the medical instrument.

11. The hermetically sealed LED light as claimed in claim 1, wherein the metal cap is coated with a nickel and/or gold containing coating.

12. A hermetically sealed LED light, comprising: a ceramic base; a plurality of LEDs on the ceramic base; a metal cap with a plurality of channels each having an upper end and a lower end, the base being hermetically soldered to the metal cap so that the plurality of LED's align with the lower end of the plurality of channels; and a plurality of glass windows each being formed from melting a glass rod hermetically sealed in the upper end of a respective one of the plurality of channels, the plurality of windows having a lenticular shape that does not protrude from the metal cap in the axial direction of the channel.

13. The hermetically sealed LED light as claimed in claim 12, further comprising a component channel extending through the base and through the metal cap, for introducing an electrical, optical, or mechanical component.

14. The hermetically sealed LED light as claimed in claim 12, wherein surface tension from melting the glass rod provides the glass window with a lenticular shape.

15. The hermetically sealed LED light as claimed in claim 14, wherein the upper end of the channel comprises a peripheral depression.

16. The hermetically sealed LED light as claimed in claim 12, wherein the ceramic base is made of made of an aluminum oxide and/or an aluminum nitride, and wherein the metal cap is made of stainless steel.

17. The hermetically sealed LED light as claimed in claim 12, further comprising a peripheral depression in an upper surface of the metal cap at the upper end of the channel, wherein the window has a lenticular shape, the peripheral depression recessing the upper end of the channel with respect to the upper surface so that the lenticular shape does not protrude from the metal cap.

18. A hermetically sealed LED light, comprising: a base made of ceramic with a plurality of LEDs thereon; a metal cap having a channel extending therethrough, the channel having an upper end and a lower end, the metal cap being soldered to the base at the lower end, the upper end having a peripheral depression; a glass window hermetically sealed to metal cap at the upper end of the channel, the window having a lenticular shape that does not protrude from the metal cap in the axial direction of the channel; and a component channel extending through the base and through the metal cap, for introducing an electrical, optical, or mechanical component.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The subject matter of the invention will now be explained with reference to exemplary embodiments.

(2) FIG. 1 shows a plan view of an exemplary embodiment of a hermetically sealed LED light.

(3) FIG. 2 is a sectional view of FIG. 1.

(4) FIG. 3 illustrates a detail of FIG. 2.

(5) FIG. 4 shows a bottom plan view.

(6) FIG. 5 is a schematic view illustrating the use of the hermetically sealed LED light according to the invention in conjunction with an image sensor.

(7) FIG. 6 is a schematic view of a medical instrument with a hermetically sealed LED light according to the invention integrated therein.

(8) FIG. 7 shows another exemplary embodiment of a hermetically sealed LED light that is not annular.

DETAILED DESCRIPTION

(9) FIG. 1 shows a plan view of an exemplary embodiment of a hermetically sealed LED light 1 according to the invention.

(10) In this embodiment, the LED light 1 has an annular shape. On the top, metal cap 2 can be seen which has a plurality of windows 3 through which the light from the underlying LEDs is emitted.

(11) LED light 1 can be connected via supply line 4.

(12) The six windows 3 illustrated in this exemplary embodiment are distributed circumferentially across the LED light 1.

(13) Furthermore, a central channel 5 with a circular cross section can be seen, which is intended to accommodate an electrical, optical, or mechanical component.

(14) FIG. 2 shows a sectional view of the LED light illustrated in FIG. 1.

(15) It can be seen that the metal cap 2 which is made of a stainless steel, is cup-shaped.

(16) A base 6 made of a ceramic material, in particular of aluminum oxide, is mounted in the cup-shaped metal cap 2 from the bottom side and is soldered to the metal cap by means of a gold-tin solder.

(17) The plate-shaped base 6 is likewise annular, so that channel 5 extends both through the base 6 and through the metal cap 2.

(18) Base 6 has feedthroughs (not shown), through which current for driving the LEDs is supplied to the upper side, via supply line 4.

(19) FIG. 3 illustrates a detail of FIG. 2, namely the region in which a window 3 is arranged.

(20) It can be seen that below window 3 the base 6 is equipped with an LED 10. LED 10 is implemented in form of a chip, in particular as a surface mounted device (SMD).

(21) On the upper side of base 6 supply lines may be provided, for example in the form of flat conductive traces (not shown) for electrically connecting the LED 10.

(22) As can further be seen, window 3 is provided in form of a lens.

(23) Window 3 is arranged in a channel 7 which in turn extends through metal cap 2.

(24) The lenticular shape of window 3 is caused by the surface tension of the glass, being produced by inserting a glass rod into channel 7 and then melting it.

(25) At the upper end of channel 7 a peripheral depression 8 is provided.

(26) Due to depression 8, the window 3 in form of a lens does not protrude.

(27) Optionally, depending on the light color that is desired, a converter 9 may be arranged in channel 7. This may in particular be a converter with a silicone matrix, which is adhesively bonded into channel 7.

(28) It can furthermore be seen that the upper surface of base 6 is soldered to the lower surface of cup-shaped metal cap 2.

(29) The edge of base 6 is spaced from metal cap 2 in this embodiment.

(30) By connecting base 6 and metal cap 2 by soldering and by melting the window 3 into the channel, a hermetic seal of the LED 10 is provided.

(31) Feedthroughs in the base 6 are preferably filled with a solder as well.

(32) For assembling the LED light according to the invention, first the metal cap is produced with the windows fused into it, and separately therefrom the base 6 is equipped with LEDs 10.

(33) These two main components are then soldered together using a gold-tin solder that has a melting temperature below 340 C., preferably below 325 C., more preferably below 300 C.

(34) The method of the invention is not only suitable for the annular LED light illustrated herein, but also for other types of lights, in particular lights that do not have a central channel.

(35) FIG. 4 shows a bottom plan view of LED light 1.

(36) Annular base 6 can be seen which in this exemplary embodiment has feedthroughs 11 and 12 via which the LEDs on the upper surface are driven.

(37) Base 6 is embedded in cup-shaped metal cap 2.

(38) Further, central channel 5 can be seen, in which an electrical, optical, or mechanical component may be arranged.

(39) Supply lines 4 extend around channel 5 on the bottom surface.

(40) It will be understood that an LED light that has a plurality of separately controlled LEDs typically will comprise more than the two feedthroughs for the positive and negative terminals as illustrated herein. That is because the driver circuits for driving the LEDs are preferably not arranged in the hermetically sealed portion of the light illustrated herein, but are rather arranged externally.

(41) FIG. 5 schematically shows a hermetically sealed LED light 1 which, again in this embodiment, comprises an annular ceramic base 6 to which a likewise annular metal cap is soldered, which has a plurality of windows 3 through which the light from LEDs 10 radiates to the outside.

(42) In the central channel 5, an image sensor 13 and a lens 14 is arranged.

(43) FIG. 6 is a schematic view of a medical instrument, especially of the head piece of a dental drilling device.

(44) A receptacle 16 can be seen, into which the drills are inserted so as to be connected to a drive shaft.

(45) A hermetically sealed LED light according to the invention is directly mounted on the head of the medical instrument 15, and the light therefrom is directly emitted to the outside, through windows 3.

(46) Because of the good sealing of the housing of the inventive light it is not necessary for the LED light to be arranged in the housing of the medical instrument and to guide the emitted light to the front end by means of light guides.

(47) FIG. 7 shows an embodiment of a hermetically sealed LED light which does not have an annular configuration but was produced by the method according to the invention.

(48) The LED light 17 comprises a base 18 made of a ceramic material, in particular aluminum oxide, to which a metal cap 19 in particular made of stainless steel has been soldered using a gold-tin solder.

(49) The base 18 is not arranged within the cap 19 but is mounted to an end face thereof.

(50) Metal cap 19 has a beveled edge. The solder 23 in the resulting gap provides for a better bond between the components.

(51) Inside the hermetically sealed LED light 19, an LED 22 configured as a chip is disposed, and the light therefrom is first incident on an overlying converter 21 which is arranged below window 20 in the form of a lens.

(52) For manufacturing this LED light 17, again, a window 20 is first produced from glass by melting the glass into the metal cap 19. Optionally, converter 21 is additionally assembled in the metal cap 19.

(53) Then, metal cap 19 is soldered to base 18 comprising the already assembled LED 22.

LIST OF REFERENCE NUMERALS

(54) 1 LED light 2 Metal cap 3 Window 4 Supply line 5 Channel 6 Base 7 Channel 8 Depression 9 Converter 10 LED 11 Feedthrough 12 Feedthrough 13 Image Sensor 14 Lens 15 Medical instrument 16 Receptacle 17 LED light 18 Base 19 Metal cap 20 Window 21 Converter 22 LED 23 Solder