1. Technical Field
The present disclosure relates to a light emitting diode (LED) lamp, and more particularly, to an LED lamp having a low cost.
2. Description of Related Art
LEDs have been available since the early 1960's. LED use has increased in a variety of applications, such as in residential, traffic, commercial, and industrial settings, because of the high light-emitting efficiency of LEDs. The applications each have its special light pattern depending on the occasion where the application is applied. For some of these applications, solid light output is often desired in order to illumination of a large area. This is generally achieved by placing a large amount of LEDs within the lamp in different levels and orientations. The light beams generated from the LEDs could be radiated towards respective orientations from respective levels, thereby providing a wide illumination to the object to be illuminated.
Compared with other elements of the lamp, the LEDs are relatively expensive for their high manufacturing cost. That is to say, the more LEDs are used, the more cost of the lamp is required. Particularly, for some kinds of lamps used in outdoors, the cost ratio of the LEDs to the whole lamp could reach nearly 50%. Thus, it is costly to apply so many LEDs in the lamp in order to provide the wide illumination.
What is needed, therefore, is an LED lamp which can overcome the above-mentioned disadvantages.
Many aspects of the present disclosure 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 disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Referring to
Also referring to
Each LED unit 20 includes an elongated printed circuit board 22, a plurality of LEDs 24 mounted atop the printed circuit board 22, a strip 26 covering the printed circuit board 22 in which the LEDs 24 protrude through the strip 26, and a plurality of lens 28 secured to the strip 26 and receiving the LEDs 24 therein, respectively. The strip 26 has a width larger than that of the printed circuit board 22, whereby two opposite longer sides of the strip 26 extend beyond the printed circuit board 22. Each lens 28 includes a conical outer surface 280 and a flared top surface 284, for concentrating light emitted from the LED 24 into a beam. Each lens 28 has a leg 282 extending towards the printed circuit board 22. The leg 282 is for locking with a corresponding longer side of the strip 26 extending beyond the printed circuit board 22, thus securing the lens 28 on the strip 26. When the printed circuit board 22 is fixed on the inner face of the substrate 52 of the heat sink 50, the LEDs 24 would be horizontally positioned towards a slightly upward direction, and the light beams output from the LEDs 24 via the lens 28 would be directed towards the reflector 70 in a slightly upward manner.
The reflector 70 is substantially received in the housing and faces the window 420 in the frame 40. The reflector 70 is formed by folding a reflective rectangular sheet into a wave-like configuration. The reflector 70 consists of multiple continuous facets 72 which are arranged at different levels and oriented towards different directions. In detailed, the facets 72 are gradually raised from two opposite ends towards a center of the reflector 70, and every two adjacent facets 72 cooperatively define an acute angle therebetween. The two opposite ends of the reflector 70 are fixed on the top face of the base 30 to cover the driving module 60. The facets 72 of the reflector 70 could reflect the light beams from the lens 28 towards different orientations from different levels, thus achieving an effect of a homogenous light, which can be obtained only when the lamp is equipped with a large number of LEDs. Since the cost of the reflector 70 is relatively low compared with the LEDs 24, the total cost of the LED lamp is reduced.
The cover 10 is also curved upwardly like the panel 42 of the frame 40. The cover 10 includes an envelope 12 and a flange 14 extending outwardly and horizontally from a circumference of a bottom of the envelope 12. The flange 14 abuts against a bottom of the panel 42 of the frame 40, to thereby secure the cover 10 to the frame 40. The envelope 12 is made of frosted glass or plastic so that the light diffusely reflected by the reflector 70 would be further diffused after passing the cover 10.
Using the two diffusion structures, the light output from the LED lamp could be distributed relatively uniformly, thereby improving illumination effect on the object to be illuminated.
It is believed that the present disclosure and its advantages will be understood from the foregoing description, and it will be apparent that various changes may be made thereto without departing from the spirit and scope of the present disclosure or sacrificing all of its material advantages, the examples hereinbefore described merely being preferred or exemplary embodiments.
Number | Date | Country | Kind |
---|---|---|---|
200910301023.5 | Mar 2009 | CN | national |