Patent Application
20150144976
1. Technical Field
The disclosure generally relates to LEDs (light emitting diodes), and more particularly, to an LED having a light divergent lens.
2. Description of Related Art
Nowadays LEDs (light emitting diodes) are applied widely in various applications for illumination. The LED is a highly pointed light source. In order to illuminate a large area, a concave lens is used with the LED to diverge the light emitted from the LED. However, the light diverging capability of the typical concave lens is still insufficient, resulting in an undesirable light distribution.
What is needed, therefore, is an LED with a light divergent lens which can address the limitations described.
Many aspects of the present embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the present embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the various views.
Referring to
The base 20 may be integrally made of a single monolithic piece of insulative material such as epoxy, silicone, ceramic or the like. The base 20 includes a plate 22 and a reflective cup 24 formed on a top face of the plate 22. The plate 22 is rectangular and thinner than the reflective cup 24. An inner circumferential face of the reflective cup 24 surrounds a cavity above the plate 22. The cavity has a diameter gradually increasing in a direction away from the plate 22. The inner circumferential face of the reflective cup 24 acts as a light reflective face 26 of the base 20 for reflecting light emitted from the chip 30 upwardly.
The chip 30 is fixed on the top face of the plate 22. The chip 30 may be made of semiconductor material such as GaN, InGaN, AlInGaN or the like. The chip 30 is electrically connected to leads (not visible) formed on the base 20 via two wires 32. The chip 30 can emit light when being activated.
The lens 40 includes a lower part 42 filling the cavity of the base 20 and an upper part 44 located above and outside the cavity of the base 20. The lower part 42 and the upper part 44 of the lens 40 are integrally made of a single monolithic piece of transparent material such as epoxy, silicone or glass. The lower part 42 is tapered and has a diameter gradually increasing in a direction away from the chip 30. The lower part 42 covers the chip 30 to seal the chip 30 from an outside environment. An inner face of the lower part 42 contacting the chip 30 acts as a light incident face 420 of the lens 40. The light emitted from the chip 30 enters the lens 40 through the light incident face 420.
The upper part 44 includes a light emerging face 440 and a connecting face 442 joined to the light emerging face 440. The light emerging face 440 includes a first face 441 and a second face 443 surrounding the first face 441. The first face 441 is a conical face having a diameter gradually decreasing in a direction towards the chip 30. The first face 441 has a lowest point located on the central axis O. Preferably, an inner angle defined between the first face 441 and the central axis O ranges between 130 degrees and 165 degrees. The second face 443 is a conical face having a diameter gradually increasing in a direction towards the chip 30. An inner angle defined between the second face 443 and the central axis O ranges between 0 and 35 degrees. The second face 443 has an area less than that of the first face 441 and larger than that of the light reflective face 26. A junction between the first face 441 and the second face 443 forms a first circle 444 which is located a highest position of the light emerging face 440. The first circle 444 is located within an outer circumferential periphery of the base 20. In other words, a diameter of the first circle 444 is less than an outer diameter of the base 20.
Also referring to
The connecting face 442 is located below the light emerging face 440. The connecting face 442 connects a top of the reflective face 26 with a bottom of the second face 443. The connecting face 442 is an annular face parallel to the top face of the plate 22. The connecting face 442 extends outwardly beyond the outer circumferential periphery of the base 20. A junction between the connecting face 442 and the second face 443 forms a second circle 445 located outside the outer circumferential periphery of the base 20. The diameter of the first circle 444 is larger than an inner diameter of the connecting face 442 and smaller than triple the inner diameter of the connecting face 442. The connecting face 442 has an area larger than that of the second face 443 and less than the first face 441.
It is to be understood, however, that even though numerous characteristics and advantages of the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102143337 | Nov 2013 | TW | national |
