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  High power led electro-optic assemblyHigh power led electro-optic assembly description/claimsThe Patent Description & Claims data below is from USPTO Patent Application 20070091618, High power led electro-optic assembly. Brief Patent Description - Full Patent Description - Patent Application Claims
FIELD OF INVENTION [0001] The present invention relates to light emitting diode ("LED") technology, particularly to improvements in LED assemblies to provide a desired optical output for various lighting applications. BACKGROUND OF THE INVENTION [0002] LED assemblies are well-known and commercially available. Such assemblies are employed in a wide variety of applications, typically for the production of ultraviolet radiation, used, for example, in effecting the curing of photo initiated adhesives and coative compositions. [0003] Several factors play into the fabrication of LED assemblies. One is the control of high current supplied to the LEDs to provide a stable and reliable UV source. Another is the position of the lens to hold the output optic in place. Also, a means to provide a path for electrical conduction is required to supply control for the LED. As the current increases to the LED, the need for a high current, high reliability electrical contact becomes necessary. Additionally, a reflector forming the rays coming from the LED is often required. Furthermore, a cooling system is required to carry the heat away from the assembly. Presently, available, LED assemblies may not adequately offer all of these requirements. [0004] Currently, manufacturers are providing a wide range of LED packages in a variety of forms. These packages range from conventional LED lamps to LEDs that use emitter chips of various sizes. While, many of the known LED assemblies produce a high light output, they produce a very disperse wide angle beam that is difficult to capture for efficient collimation and beam imaging in practical application, such as in a flashlight. As a result, a great deal of the output energy is lost as leakage out from the side of the LED package. [0005] Additionally, light emitted from the LED assembly is ordinarily not evenly distributed. The shape of the light-emitting chip is projected on the target as a high intensity area. Reflections from the electrodes and walls from unpredictable patterns of light are superimposed on the main beam of light. As a result, undesirable hot spots and shadows appear on the object being illuminated. Accordingly, for any lighting application requiring a substantially even or uniform distribution of light over a predetermined area, a transmitting or partial diffuser must be used to scatter the light emitted from each individual LED assembly so that the hot spots and shadows do not appear on the object being illuminated. But, while a diffuser will eliminate hot spots and shadows, it is important that the "directivity" or geometry of the light beam emitted from an individual LED assembly not be degraded or diminished. [0006] In order to overcome these above-noted disadvantages of known light sources, there is a need to provide an LED curing lamp assembly that has a flexible design, is easy to manufacture and reduces assembly cost. SUMMARY OF THE INVENTION [0007] In one embodiment of the present invention there is disclosed a LED electro-optic electrical sleeve assembly having a generally cylindrical sleeve coated with an electrical insulator. The assembly is divided into an upper portion and a lower portion, the upper and lower portion separated by an insulating material. At least one LED and a conductive reflector is mounted at the upper portion, where the reflector surrounds the LED. A conductive heat sink is mounted at the lower portion, and is in electrical engagement with the LED. Additionally a conductive bonding pin extends through the conductive reflector and is in conductive engagement therewith. An electrical engagement electrically engages the bonding pin to the LED, where the heat sink and the reflector form an electrically conductive location for supplying power to said LED. BRIEF DESCRIPTION OF THE DRAWINGS [0008] FIG. 1 is a schematic view of a LED ray forming contact assembly of the present invention. [0009] FIG. 2 is a schematic view of a LED optical transform assembly using the ray forming contact assembly of FIG. 1. [0010] FIG. 3 is a schematic view of an electrical sleeve assembly of the present invention. [0011] FIG. 4 is a schematic view of a LED, Electro-optic Assembly of the present invention. DETAILED DESCRIPTION OF THE INVENTION [0012] Referring to FIG. 1 of the present invention, there is shown a schematic view of a LED ray forming contact assembly 10. The assembly 10 is a compact means of providing a way to simultaneously contact the LED with electrical contacts and form the rays coming from the LED as will be described hereinbelow. The contact assembly 10 is divided into two contacts, i.e., electrodes, an upper electrode 10a and lower electrode 10b, both made of metal. The upper electrode 10a includes a metal reflector 12 preferably made of aluminum. The metal reflector 12 is press fit into the electrode 10a to form a conductor reflector assembly. The metal reflector 12 may be shaped as a curve and functions to generally collimate and direct the LED light towards the lens and will be described in greater detail below. In a preferred embodiment, the reflector 12 is shaped as an elliptic. A LED chip 14 is mounted in the electrode 10a, desirably positioned at the center and partially or wholly surrounded by the reflector 12. The LED chip 14 is further electrically isolated from the reflector 12. Because metal is a good electrical conductor, both the metal reflector 12 and the metal electrode 10a provide an electrical transfer path away from the LED chip 14. A conductive metal pin 15 desirably coated with gold is pressed into the assembly 10 in the upper electrode 10a as shown in FIG. 1. An electrical engagement such as a gold wire or wires 16 passes from the upper electrode 10a to the lead chip 14. One end of the gold wire 16 is soldered to the metal pin 15 and the other end is welded to the top surface of the LED chip 12 to electrically engage the pin 15 with the LED 14. [0013] When current flows through a chip in an individual LED assembly, both light and heat are generated. Increasing the current through the chip raises the light output but increased current flow also raises the temperature of the chip in the individual LED assembly. This temperature increase lowers the efficiency of the chip. Overheating is the main cause of the failure of individual LED assemblies. To assure safe operation, either the current, and as a result the light output, must be kept at a low level or some other means of transferring heat away from the chip in the individual LED assembly must be provided. Therefore, lower electrode 10b may be defined by with an electrically conducting thermal heat sink 18 which also serves to carry heat away from the LED chip 14. The upper electrode 10a and the lower electrode 10b are held together by an electrically insulating material 19 such as a non-conductive adhesive. The LED 14 is disposed in the assembly 10 in such a manner that the bottom surface is bonded or soldered to the thermal heat sink 18 via the bond material 19. In order to allow the electrical connection through the LED 14, voltage is applied to both upper and lower electrodes 10a and 10b respectively. This causes the heat sink 18 to carry off heat and the curved surface of the reflector 12 forms the light from the LED 14 into a desired pattern. Even though only single LED 14 is shown in FIG. 1, it is understood that multiple LEDs can be employed in the assembly 10. [0014] By providing one of the electrical contacts 10a in conjunction with the reflector and the other electrical contact 10b in conjunction with thermal heat sink, the LED ray forming contact assembly 10 is easy to manufacture, reduces the assembly cost and simplifies the final assembly. Furthermore, the LED ray forming contact assembly 10 also allows the scaling up to multiple LEDs in an assembly without adding significant complexity. [0015] To further exemplify the operation of the entire optical assembly FIG. 2A-FIG. 2C illustrate an exemplary ray diagrams for a single LED assembly. It will be understood by those skilled in the art that a similar ray diagram results when the LED chip 14 of the single LED assembly is replaced by multiple LED chips 14. [0016] FIG. 2A-FIG. 2C show a LED optical transform assembly 20 using the LED forming contact assembly 10 of FIG. 1 in conjunction with miniature optical components to form a complete ray forming system. The optical components include a lens 22 that directs the light generated by the LED chip 14 by focusing the light to a desired spot size by collimating the light to a desired location. The lens 22 may be attached or molded precisely in the assembly so that it is centered at the collimated beam. The shape and/or size of the lens 22 may vary to shape the conical beam of light emitted from the LED assemblies to provide the desired optical illumination pattern. [0017] The converging action of the lens 22 depends on both the radius of lens 22 and the positioning of the lens 22 with respect to the individual LED assembly 20. Both the radius and position of the lens 22 may be established during the design process to optimize illumination of the object. The ability to precisely locate and fixture the optic lens 22 is a critical concept in this application. The lens 22 needs to be positioned at right distance from the LED 14 in order to achieve the desired light output. [0018] In FIG. 2A, an optical lens 22a in shape of ball is partially located in the reflector 12 of the upper electrode 10a. Even though a ball shaped optic lens 22a is shown in the present invention, it is understood that other different shapes of optics can be selected. The optics can be varied depending on the desired output. In the present invention, ball optic 22a is selected in order to produce the maximum light power density with the available LED output. The LED output is focused to a desired spot just outside the ball optic lens 22a. If a collimated beam is desired, a half ball optical lens 22b as shown in FIG. 2B or a parabolic optical lens 22c shown in FIG. 2C may desirably be used. The parabolic optical lens 22b of FIG. 2B is positioned in such a manner that part of the lens lies in the reflector 12 and the other part is outside the assembly 20. This positioning of lens 22b emits a wide light pattern as shown in FIG. 2B thereby illuminating a much bigger area on a work piece. Whereas, the parabolic optical lens 22c, as shown in FIG. 2C, is positioned completely outside the reflector 12 and/or the assembly 20. This positioning of lens 22c in FIG. 2C emits a narrower light pattern than the area in FIG. 2B thereby illuminating a specific area on a work piece. This method provides a rigid assembly that can be manufactured precisely and rapidly. The LED ray forming contact assembly size, other optics lenses 22 can preferably be modified and further distances and positions between the LED 14 and the lens 22 can be varied to accommodate a wide range of optical components while minimizing the cost and complexity of the complete assembly. [0019] The number of LED assemblies employed determines the size of a LED array and the desired output intensity. An end user can easily increase or decrease the output intensity by adding/removing LED assemblies to/from the LED array. Also, a user can change the operating wavelength of the assembly by replacing one or more LED assemblies of a first operating wavelength with one or more replacement assemblies having a second wavelength. In addition, a user can replace damaged or expired LED assemblies without replacing the entire LED array. Continue reading about High power led electro-optic assembly... Full patent description for High power led electro-optic assembly Brief Patent Description - Full Patent Description - Patent Application Claims Click on the above for other options relating to this High power led electro-optic assembly patent application. ###  How KEYWORD MONITOR works... a FREE service from FreshPatents1. Sign up (takes 30 seconds). 2. Fill in the keywords to be monitored. 3. Each week you receive an email with patent applications related to your keywords. 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