BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a rotatable LED arrangement disclosed in U.S. Pat. No. 6,315,432, entitled “Light-emitting Diode (LED) device”.
FIG. 2 shows a rotatable LED arrangement disclosed in U.S. Pat. No. 6,450,663, entitled “Light-emitting Diode Arrangement”.
FIG. 3A shows a cycling LED lamp disclosed in JP Pat. 2002324405.
FIG. 3B is a cross-sectional view of FIG. 3A.
FIG. 4 shows an improved bottom-light LED luminaire is disclosed in U.S. Pat. No. 5,136,483, entitled “Illumination Device”.
FIG. 5 shows a rotatable inclined LED arrangement disclosed in JP Pat. 2004327670.
FIG. 6 shows a refractive illumination device according to a preferred embodiment of the invention.
FIG. 6A shows a path of a light beam as it is traveling between different media.
FIG. 7 shows a refractive illumination device according to another preferred embodiment of the invention.
FIG. 8 shows a refractive illumination device of the invention, being an integrated structure of two symmetrically arranged illumination devices of FIG. 6.
FIG. 9 shows another refractive illumination device of the invention, similar to that shown in FIG. 6 but with a two-layered light-control microstructure.
FIG. 10 shows a reflective illumination device according to a preferred embodiment of the invention.
FIG. 11 shows a reflective illumination device according to another preferred embodiment of the invention.
FIG. 12 shows a reflective illumination device of the invention, being an integrated structure of two symmetrically arranged illumination devices of FIG. 10.
FIG. 13 shows an illumination device with a plurality of directional light sources being fitted therein in a manner that they are disposed on a surrounding sidewall of a round-shaped light guide cover of the illumination device.
FIG. 14 shows an illumination device have a layer of refractive light-control microstructure and a layer of reflective light-control microstructure according to a preferred embodiment of the invention.
FIG. 15 shows an illumination device of the invention, being an integrated structure of an illumination device with refractive light-control microstructure and another illumination device with reflective light-control microstructure.
FIG. 16 is an exploded diagram illustrating an adjustment unit according to a preferred embodiment of the invention.
FIG. 17 shows an assembling of the adjustment unit of FIG. 16.
FIG. 18 shows an illumination device of the invention, being applied in a street lamp.
DESCRIPTION OF THE PREFERRED EMBODIMENT
For your esteemed members of reviewing committee to further understand and recognize the fulfilled functions and structural characteristics of the invention, several preferable embodiments cooperating with detailed description are presented as the follows.
Please refer to FIG. 6, which shows a refractive illumination device according to a preferred embodiment of the invention. The refractive illumination device 10 uses a light emitting diode (LED) 20 as its light source that the LED 20, as a directional light source, can be replaced and substituted by another type of directional light source and thus is not limited thereby. The LED 20 is capable of emanating light as being electrically conducted to a control circuit and has ability to adjust a light-emitting angle thereof for varying the angle of the light being discharged therefrom. As seen in FIG. 6, the LED 20 is being received inside a light guide cover 30, which is composed of: a bottom 31; a sidewall 32, vertically arranged at the circumference of the bottom 31 while surrounding the same; and a projection surface 33, being disposed inside the enclosure of the sidewall 32 at a position corresponding to the bottom 31. Moreover, a light-control microstructure 40, composed of a plurality of microsurfaces 41 with refractive characteristics, is formed on the projection surface 33, whereas the combined structure of the projection surface 33 and the light-control microstructure 40 is so constructed for enabling light to pass therethrough. It is noted that the sawtooth-like surface of the light-control microstructure 40 is one possible structure capable of being achieved by the plural microsurface 41 which is used only for illustration and is not limited thereby as it can be any irregular surface composed of planar facets and curved facets.
It is known that refraction is the bending of the path of a light wave as it passes across the boundary separating two media that is caused by the change in speed experienced by a light wave when it changes medium. As seen in FIG. 6A, as a light bam is directed toward a boundary separating two media n1 and n2, a portion of the ray is reflected while the rest being refract, bending towards the normal (since the light is passing from a medium in which it travels fast, i.e. n1, into one in which it travels slow, i.e. n2. According to Snell's law, the refraction of light as it crosses from one material into a second material yields a general relationship between the sines of the angle of incidence, i.e. θi, and the angle of refraction, i.e. θt. This general relationship is expressed by the following equation:
n
1 sin θi=n2 sin θt
- whereas n1 indicates the refraction index of the media n1;
- n2 indicates the refraction index of the media n2; Moreover, according to the Law of Reflection that θi, the angle of incidence, is equal to θr, the angle of reflection, that is,
θi=θr
Therefore, as seen in FIG. 6, when the light L1 emitted from the LED 20 strikes on the plural microsurfaces 41 of the light-control microstructure 40, it is refracted as indicated by the refracted light L2 and being discharged out of the light guide cover 30. Furthermore, since the light-emitting angle of the LED 20 is adjustable, the position of the light L1 impinging upon the light-control microstructure 40 can be varied, the angle of the refracted light L2 being discharged out of the light guide cover 30 can be varied accordingly. In addition, as the bottom 31 and the sidewall 32 of the light guide cover 30 are chosen to be made of a reflective material, or either being covered by a reflective diffusion film or the electroplating of a layer of metal, such as aluminum or electroless nickel, etc., the reflection efficiency of the light guide cover 30 is enhanced.
In a preferred embodiment of the invention, a structure of Fresnel lens can be formed on the light-control microstructure 40. A Fresnel lens replaces the curved surface of a conventional lens with a series of concentric grooves, molded into the surface of a thin, lightweight sheet. The grooves act as individual refracting surfaces, like tiny prisms when viewed in cross section, bending parallel rays in a very close approximation to a common focal length. Thus, the Fresnel lens is a succession of concentric rings, each consisting of an element of a simple lens, assembled in proper relationship on a flat surface to provide a short focal length. Fresnel lenses are advantageous in its super light gathering/focusing ability that it is being vastly applied in various optical instruments. In addition to the aforesaid Fresnel lens, other optical structures, such as semi-Fresnel lens, can be formed on the light-control microstructure 40 as well, only if such optical structure can control the angle of the refracted light being discharged in a way the same as that of the microsurfaces 41 formed on the light-control microstructure 40.
Please refer to FIG. 7, which shows a refractive illumination device according to another preferred embodiment of the invention. The refractive illumination device 10 is comprised of: at least an LED, each having ability to adjust a light-emitting angle thereof for varying the angle of the light being discharged therefrom; a light guide cover 30, having a bottom 31, a sidewall 32 and a projection surface 133, being disposed inside the enclosure of the sidewall 32 at a position corresponding to the bottom 31; and a light-control microstructure 40, formed on the projection surface 133. As the functions of the aforesaid components of the refractive illumination device 110 are similar to those of the refractive illumination device 10 and thus are not described further herein. The characteristic of the refractive illumination device 110 is that: the projection surface is a curved surface, whereas that of the refractive illumination device 11 is a planar surface, and thus the light-control microstructure 40 is formed with a curvature the same as that of the curved projection surface 133. Therefore, according to Snell's law, when the light L1 emitted from the LED 20 strikes on the plural microsurfaces 41 of the light-control microstructure 40, it is refracted as indicated by the refracted light L2 and being discharged out of the light guide cover 30 form the projection surface 33. Furthermore, since the light-emitting angle of the LED 20 is adjustable, the position of the light L1 impinging upon the light-control microstructure 40 can be varied, the angle of the refracted light L2 being discharged out of the light guide cover 30 can be varied accordingly.
Please refer to FIG. 8, which shows a refractive illumination device of the invention, being an integrated structure of two symmetrically arranged illumination devices of FIG. 6. The refractive illumination device 210 is comprised of: two LEDs 20a, 20b, symmetrically arranged with respect to an axis of the refractive illumination device 210, each having ability to adjust a light-emitting angle thereof for varying the angle of the light being discharged therefrom; a light guide cover 30, having a bottom 31, a sidewall 32 and a projection surface 33; and a light-control microstructure 240, formed on the projection surface 33; wherein, the on/off and the light-emitting angle of the two LEDs can be controlled independent to each other and thus the refractive illumination device 210 can be control to light-up at an one-sided mode whereas only one of the two LEDs 20a, 20b are turned on, or at a two-sided mode whereas both LEDs 20a, 20b are turned on. The characteristic of the refractive illumination device 210 is that: the light-control microstructure 240 are structured symmetrically with respect to the axis of the refractive illumination device 210 while enabling each half thereof to correspond to one of the two LEDs 20a, 20b. As the functions of the aforesaid components of the refractive illumination device 210 are similar to those of the refractive illumination device 10 and thus are not described further herein. Similarly, according to Snell's law, when the light L1a, L1b, emitted respectively from the LEDs 20a, 20b strike on the plural microsurfaces 241 of the light-control microstructure 240, they are refracted as indicated respectively by the refracted light L2a, L2b and being discharged out of the light guide cover 30 form the projection surface 33. Furthermore, since the light-emitting angles of the LED 20a, 20b are adjustable in a manner that they are adjusted independent to each other, the positions of the light L1a, L1b impinging upon the light-control microstructure 40 can be varied and strike at two different positions, the angles of the refracted light L2a, L2b, being discharged out of the light guide cover 30 can be varied accordingly. It is noted that the projection surface 33 where the light-control microstructure 240 is formed is a curved surface similar to that the curved projection surface 133 shown in FIG. 7.
Please refer to FIG. 9, which shows another refractive illumination device of the invention, similar to that shown in FIG. 6 but with a two-layered light-control microstructure. The refractive illumination device 310 is comprised of: two LEDs 20a, 20b, symmetrically arranged with respect to an axis of the refractive illumination device 310, each having ability to adjust a light-emitting angle thereof for varying the angle of the light being discharged therefrom; a light guide cover 30, having a bottom 31, a sidewall 32 and a projection surface 33; and a two-layered light-control microstructure 340, formed on the projection surface 33; wherein, the on/off and the light-emitting angle of the two LEDs can be controlled independent to each other. As the functions of the aforesaid components of the refractive illumination device 310 are similar to those of the refractive illumination device 210 and thus are not described further herein. It is noted that the refractive illumination device 310 is characterized by the two-layered light-control microstructure 340, each having a plurality of microsurfaces formed thereon, respectively represented by the two layers of microsurfaces 341 and 342. Similarly, according to Snell's law, when the light L1a emitted from the LED 20a, strikes on the first layer of microsurfaces 341 of the light-control microstructure 340, it is refracted and directed to strike on the second layer of microsurfaces 342, as indicated by the refracted light L2a, where it is refracted again, as indicated by the refracted light L3a, to be discharged out of the light guide cover 30. In addition, as the control of the LED 20b is independent to that of the LED 20a, the LED 20b can emit a light L1b at an angle different to that of the LED 20a so that the light L1b will strike on a position of the two-layered light-control microstructure 340 different than the L1a. Thereby, when the light L1b emitted from the LED 20a, strikes on the first layer of microsurfaces 341 of the light-control microstructure 340, it is refracted and directed to strike on the second layer of microsurfaces 342, as indicated by the refracted light L2b, where it is refracted again, as indicated by the refracted light L3b, to be discharged out of the light guide cover 30. It is noted that the orientations of different layers of microsurfaces can be different from each other and thus are not limited to the parallel arrangement shown in FIG. 9. Moreover, as the light-emitting angles of the LED 20a, 20b are adjustable in a manner that they are adjusted independent to each other, the positions of the light L1a, L1b impinging upon the light-control microstructure 340 can be varied and strike at two different positions, the angles of the refracted light L3a, L3b, being discharged out of the light guide cover 30 can be varied accordingly.
Please refer to FIG. 10, which shows a reflective illumination device according to a preferred embodiment of the invention. Different from the foregoing refractive illumination device, the illumination device shown in FIG. 10 is a reflective illumination device, comprising: an LED 20 with ability to adjust the light-emitting angle thereof; a light guide cover 430, having a projection surface 433 and a sidewall 32, vertically arranged at the circumference of the projection surface while surrounding the same; and a light exit 434, being disposed inside the enclosure of the sidewall 32 at a position corresponding to the projection surface 433. Moreover, a light-control microstructure 440, composed of a plurality of microsurfaces 441 with reflective characteristics, is formed on the projection surface 433, whereas the combined structure of the projection surface 433 and the light-control microstructure 440 is so constructed for enabling light to be reflected therefrom. It is noted that the sawtooth-like surface of the light-control microstructure 440 is one possible structure capable of being achieved by the plural microsurface 441 that is used only for illustration and is not limited thereby as it can be any irregular surface composed of planar facets and curved facets.
According to the Law of Reflection that θi, the angle of incidence, is equal to θr, the angle of reflection, when the light L1 emitted from the LED 20 strikes on the plural microsurfaces 441 of the light-control microstructure 440, it is reflected as indicated by the refracted light L4 and being discharged out of the light guide cover 430 from the light exit 434. Furthermore, since the light-emitting angle of the LED 20 is adjustable, the position of the light L1 impinging upon the light-control microstructure 40 can be varied, the angle of the reflected light L4 being discharged out of the light guide cover 430 can be varied accordingly. In addition, as the light guide cover 30 can be made of a reflective material, or the sidewall 32 thereof can either being covered by a reflective diffusion film or the electroplating of a layer of metal, such as aluminum or electroless nickel, etc., the reflection efficiency of the light guide cover 430 is enhanced
Please refer to FIG. 11, which shows a reflective illumination device according to another preferred embodiment of the invention. The reflective illumination device 510 shown in FIG. 11 is comprised of: an LED 20 with ability to adjust the light-emitting angle thereof; a light guide cover 430, having a projection surface 533 and a sidewall 32, vertically arranged at the circumference of the projection surface while surrounding the same; and a light exit 434, being disposed inside the enclosure of the sidewall 32 at a position corresponding to the projection surface 533. Moreover, a light-control microstructure 440, composed of a plurality of microsurfaces 441 with reflective characteristics, is formed on the projection surface 533. As the functions of the aforesaid components of the reflective illumination device 510 are similar to those of the refractive illumination device 410 of FIG. 10 and thus are not described further herein. The characteristic of the reflective illumination device 510 is that: the projection surface 533 is a curved surface, whereas that of the reflective illumination device 410 is a planar surface, and thus the light-control microstructure 440 is formed with a curvature the same as that of the curved projection surface 533. Therefore, according to Law of Reflection, when the light L1 emitted from the LED 20 strikes on the plural microsurfaces 441 of the light-control microstructure 440, it is reflected as indicated by the refracted light L4 and being discharged out of the light guide cover 430 form the light exit 434. Furthermore, since the light-emitting angle of the LED 20 is adjustable, the position of the light L1 impinging upon the light-control microstructure 440 can be varied, the angle of the refracted light L4 being discharged out of the light guide cover 430 can be varied accordingly.
Please refer to FIG. 12, which shows a reflective illumination device of the invention, being an integrated structure of two symmetrically arranged illumination devices of FIG. 10. The reflective illumination device 610 is comprised of: two LEDs 20a, 20b, symmetrically arranged with respect to an axis of the refractive illumination device 610, each having ability to adjust a light-emitting angle thereof for varying the angle of the light being discharged therefrom; a light guide cover 430, having a sidewall 32, a projection surface 433 and a light exit 434; and a light-control microstructure 440, formed on the projection surface 433 at a side thereof facing toward the light exit 434; wherein, the on/off and the light-emitting angle of the two LEDs can be controlled independent to each other and thus the refractive illumination device 610 can be control to light-up at an one-sided mode whereas only one of the two LEDs 20a, 20b are turned on, or at a two-sided mode whereas both LEDs 20a, 20b are turned on. The characteristic of the refractive illumination device 610 is that: the light-control microstructure 440 are structured symmetrically with respect to the axis of the refractive illumination device 21 while enabling each half thereof to correspond to one of the two LEDs 20a, 20b. As the functions of the aforesaid components of the reflective illumination device 610 are similar to those of the refractive illumination device 410 and thus are not described further herein. Similarly, according to the Snell's law, when the light L1a, L1b, emitted respectively from the LEDs 20a, 20b strike on the plural microsurfaces 441 of the light-control microstructure 440, they are reflected as indicated respectively by the reflected light L4a, L4b and being discharged out of the light guide cover 430 form the light exit 434. Furthermore, since the light-emitting angles of the LED 20a, 20b are adjustable in a manner that they are adjusted independent to each other, the positions of the light L1a, L1b impinging upon the light-control microstructure 440 can be varied and strike at two different positions, the angles of the refracted light L4a, L4b, being discharged out of the light guide cover 430 can be varied accordingly. It is noted that the projection surface 433 where the light-control microstructure 440 is formed can be a curved surface similar to that the curved projection surface 533 shown in FIG. 11.
Please refer to FIG. 13, which shows an illumination device with a plurality of directional light sources being fitted therein in a manner that they are disposed on a surrounding sidewall of a round-shaped light guide cover of the illumination device. As seen in FIG. 13, the illumination device 710 is configured with a round-shaped light guide cover 730, whose surrounding sidewall 732 is fitted with a plurality of LEDs 20 in a manner that all the light L1 emitted from the plural LEDs are directed toward the center of the round-shaped light guide cover 730. With such arranging of the LEDs 20 at the round-shaped light guide cover 730, no matter it is paired to work with a light-control microstructure 40 with refractive characteristics as that shown in FIG. 6 or another light-control microstructure 440 with reflective characteristics as that shown in FIG. 10, the light L1 can all be reflected or refracted into a single light beam to be discharged out of the light guide cover 730. However, as the light-emitting angles of the plural LED 20 are adjustable in a manner that they can be adjusted independent to each other, each LED 20 can be adjust to have different light-emitting angles so that there may be various light beams being discharged out of the light guide cover 730 in different directions.
Please refer to FIG. 14, which shows an illumination device have a layer of refractive light-control microstructure and a layer of reflective light-control microstructure according to a preferred embodiment of the invention. The illumination device 810 is comprised of: two LEDs 20a, 20b, symmetrically arranged with respect to an axis of the illumination device 810, each having ability to adjust a light-emitting angle thereof for varying the angle of the light being discharged therefrom; a light guide cover 430, having a sidewall 432, a projection surface 433 and a light exit 434; and a reflective light-control microstructure 440, formed on the projection surface 433 at a side thereof facing toward the light exit 434. As the functions of the aforesaid components of the reflective illumination device 810 are similar to those of the refractive illumination device 410 and thus are not described further herein. The characteristic of the illumination device 810 is that: an additional light-control microstructure 240 having refractive microsurface 241 is formed on a projection surface of the light exit 434. Thus, according to the Snell's law and Law of Reflection, when the light L1a emitted respectively from the LED 20a strike on the plural reflective microsurfaces 441 of the light-control microstructure 440, they are reflected as indicated by the reflected light L4a and directed to strike on the refractive microsurface 241 of the additional light-control microstructure 240, where it is refracted and forms a refracted light L2a, to be discharged out of the light guide cover 430. In addition, as the control of the LED 20b is independent to that of the LED 20a, the LED 20b can emit a light L1b at an angle different to that of the LED 20a so that the light L1b will strike on a position of the reflective light-control microstructure 440 different than the L1a. Thereby, when the light L1b emitted from the LED 20a, strikes on the reflective microsurfaces 441 of the light-control microstructure 440, it is reflected, as indicated by the reflected light L4b, and directed to strike on the refractive microsurfaces 241 of the additional light-control microstructure 240, where it is refracted to form a refracted light L2b and discharged out of the light guide cover 430, whereas the refracted light L2b is being discharged out of the light guide cover 430 at an angle different than that of the refracted light L2a. It is noted that the projection surfaces 33, 433 where the light-control microstructures 240, 440 are formed respectively, can each be a curved surface similar to that the curved projection surfaces 133, 533 respectively shown in FIG. 7 and FIG. 11.
Please refer to FIG. 15, which shows an illumination device of the invention, being an integrated structure of an illumination device with refractive light-control microstructure and another illumination device with reflective light-control microstructure. The illumination device 910 can be considered as an integrated structure of the refractive illumination device 10 of FIG. 6 and the reflective illumination device 410 of FIG. 10. As seen in FIG. 15, an additional sidewall is arranged at the middle portion of the light guide cover 930 of the illumination device 910 while a refractive device similar to the refractive illumination device 10 of FIG. 6 is positioned at the left of the light guide cover 930 and another device similar to the reflective illumination device 410 of FIG. 10 is positioned at the right of the light guide cover 930. For enabling the light to be discharged out of the illumination device 910 from the same side thereof, that is, the reflected light of the reflective device is discharged out of the illumination device from the side thereof the same as that of the refractive device, it is required to position the reflective device up-side-down with respect to the refractive device, and vice versa. With the aforesaid integrated structure, the reflected light L4b of the light L1b emitted by the LED 20b and the refracted light L2a of the light L1a emitted by the LED 20a can be directed to discharge out of the light guide cover 930 form the same side thereof. Similarly, all the other illumination devices can be integrated into an integrated illumination device in a manner similar to that shown in FIG. 15, by which various lighting effects can be achieved.
In a preferred aspect, the light guide cover has a plurality of light-control microstructures formed thereon in a multi-layer formation as each layer is formed by one of the plural light-control microstructure and the microsurfaces formed on the different layer of the multi-layered light-control microstructure. In addition, a surface of each light-control microstructure where its microsurface is distributed can be a surface selected from the group consisted of a planar surface, a curved surface and the combination thereof. In another preferred aspect, the cross section of the microsurface-distributed surface of each light-control microstructure is symmetrical with respect to a central axis thereof whereas each semi-section of the microsurface-distributed surface can be a surface selected from the group consisting of an inclined surface, a curved surface and the combination thereof. Thus, with respect to the structure of the light-control microstructure 240, the plural microsurfaces of each microsurface-distributed surface is formed thereon by a manner selected from the group consisting of an encircling manner, a symmetrical-distributing manner, a parallel-extending manner and the combination thereof, whereas the manner is selected matching the arrangement of LEDs as well as the light-emitting angles corresponding to the LED arrangement. Please refer to FIG. 16 and FIG. 17, which are respectively an exploded diagram illustrating an adjustment unit according to a preferred embodiment of the invention and the assembly thereof. As seen in the figures, an LED 20 is mounted on an adjustment unit 50, which is comprised of a seat 51 and a moveable part 52. The seat 51 is fixedly arranged inside a light guide cover, such as the light guide cover 30 shown in FIG. 6, that the seat 51 is configured with at two holding parts 511, being arranged at positions corresponding to each other while enabling retaining portions 512 of the two holding parts to be coaxially arranged. Moreover, the moveable part 52 is configured with a carrier surface 521, provided for the LED 20 to mounted thereon, and two posts 522, each formed on the carrier surface 521 at a position enabling the same to correspondent to a retaining portions 512. Thus, by inserting each post 522 into its corresponding retaining portion 512, the movable part 52 can be pivotally connected to the seat 51 since the two posts 522 are able to rotate freely in the corresponding retaining portion 512 in full circumference with respect to an axis of the retaining portions 512 and the posts 522. In a preferred embodiment, the LED 20 is a chip-type LED, and the seat 51 as well as the moveable part 50 are all made of a material with thermal/electrical conductivity selected from the group consisting of iron, aluminum, magnesium, copper and the like, and the alloy thereof. As the adjustment unit 50 is made of the material with thermal/electrical conductivity, the heat generated from the operating LED 20 can de dissipated therefrom rapidly. Moreover, as the LED 20 is designed with good heat-dissipating ability, it can be received in a transparent tube for protecting the same and the tube can be made of a material selected from the group consisting of a glass, a plastic and the combination thereof. In a preferred aspect, the LED 20 is connected to a protective circuit, composed of overload protection devices, such as fuse, and current regulator, so that the lifespan of the LED 20 can be prolonged.
It is noted that the adjustment unit 50 shown in FIG. 16 and FIG. 14 is only an illustration and is not limited thereby. In another preferred embodiment, the seat 51 is configured with a ball-like retaining portion 512 and the moveable part 52 is shaped like a ball while being provided for the LED to mount thereon. By inserting the ball-shaped moveable part 52 into the ball-like retaining portion 512 of the seat 51, the movable part 52 is pivotally connected to the seat 51 while the ball-shaped moveable part 52 is enabled to rotate freely in the ball-like retaining portion 512 at any angle at will.
Please refer to FIG. 18, which shows an illumination device of the invention, being applied in a street lamp. While an reflective illumination device 410 as that shown in FIG. 10 is being applied in a street lamp, the angle of the light being discharged out of the light guide cover 430 can be varied with the adjustment of the light-emitting angle of the LED 20. Thereby, The street lamp is enabled to illuminate different areas, such as the two areas A1 and A1 shown in FIG. 18 and thus light-up different areas of the ground 60 correspondingly. When an illumination device with a plurality of LEDs 20 being fitted therein in a manner that they are disposed on a surrounding sidewall of a round-shaped light guide cover of the illumination device, as that shown in FIG. 13, is being applied in a street lamp, the light being discharged out of the street lamp can have various geometrical shapes, such as oval shape or circular shape, with respect to the adjustment of the light-emitting angle of each LED 20. Similarly, the refractive illumination device 10 as that shown in FIG. 6 can also achieve the same effect.
To sum up, the illumination device of the invention is an illumination device capable of varying the angle of the light being discharged out of the illumination device by adjusting the light-emitting angle of its light sources with respect to a use's preference and the same time matching the adjustment with a light-control structure formed on its light guide cover, by which not only glare can be eliminated, but also the light pattern and the angle of the light being discharged out of the light guide cover preferred by a user can be achieved so that the illumination devices is enabled to be more versatile since it is freed from the restrictions limiting the appearance design of the light cover as well as those limiting the manufacturing of LED circuits. In addition, as the shape of each LED used in the illumination device of the invention can be standardized to be mounted on a standardized seat fitted in the illumination device, it is easy to be altered with respect to the preference of a user that the illumination device of the invention is a device characterized by its high light efficiency, easy to maintain, flexibility, light weight and compact design.
While the preferred embodiment of the invention has been set forth for the purpose of disclosure, modifications of the disclosed embodiment of the invention as well as other embodiments thereof may occur to those skilled in the art. Accordingly, the appended claims are intended to cover all embodiments which do not depart from the spirit and scope of the invention.
Patent Application
20070263388
