Patent Application
20070235747
This invention relates to light sources and more particularly to light sources having compliant interfaces and even more particularly to such light sources for use in forming light guide panels.
Light sources are used for many applications. For example, an LED light source having a flat top is pressed into contact with light guide material to form light guide panels (LGP). In such applications, the light from the LED source must pass in and through the LGP and thus it is important that the bond between the LED and the light guide material have low light loss. As LEDs are currently constructed, the interface between the LED and the panel results in air gaps being formed. These are gaps have relatively high light loss.
A typical solution to reduce the light loss (and thereby increase the efficiency of the device's performance) is to flow a compliant sealer (such as silicone) between the top of the LED and the light guide material. This gap-filling solution is time-consuming and requires skill to achieve a proper insertion of the compliant sealant. Excess sealant seeps out and causes additional problems. Accordingly, the yield rate using this procedure is poor.
A compliant interface is added above the top housing of a light source, such as an LED during LED manufacture. The compliant interface allows for a low light loss transfer between the surface of the light guide material. The compliant structure is, in one embodiment, a light transparent compliant silicone molded (by curing the liquid silicone) onto the top surface of the light source. In one embodiment, the compliant interface can be integrated as part of the encapsulated material surrounding the LED chip.
During construction of the light device encapsulant 13, which can, for example, be liquid silicone, is flowed around light source 12. This encapsulant fills the cavity from bottom surface 11-1 to top surface 11-2. The top surface of the cavity is the same height as housing 11 since housing 11 is the mold by which encapsulant 13 is formed. Encapsulant 13 is cured to form a flat-topped LED in the well-known manner. At this point, compliant layer 14 is formed above housing 11, as will be discussed with respect to
Although the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
This application claims priority benefit of U.S. patent application Ser. No. 11/400,951 entitled “LIGHT SOURCE WITH COMPLIANT INTERFACE,” filed Apr. 10, 2006, the disclosure of which is hereby incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 11400951 | Apr 2006 | US |
| Child | 11412697 | Apr 2006 | US |
