TWI507638B - Light emitting diode lighting device - Google Patents

Description

Light-emitting diode lighting device

The invention relates to a light-emitting diode lighting device, in particular to a light-emitting diode lighting device with a narrow light field.

Lighting devices play an important role in human life, and can be seen in a variety of buildings, vehicles, or decorations. For humans, lighting devices are not only a tool for providing lighting, but lighting devices have a strong influence on human life.

Currently common lighting devices include incandescent lamps, fluorescent lamps, and light-emitting diode (LED) lamps, and the like. Conventional incandescent lamps energize the tungsten wire to produce high thermal illumination for illumination. However, this type of illumination is very power-hungry, making incandescent lamps gradually replaced by fluorescent lamps.

Fluorescent lamps emit electrons by applying a high voltage to the electrodes, causing electrons to strike atoms of the mercury vapor, causing ionization and excitation. When the mercury vapor atom returns from the excited state to the original state, an electromagnetic wave having a wavelength of 253.7 nm is emitted, which is in the range of the invisible light of the human eye. Therefore, by using a variety of different fluorescent substances to absorb the electromagnetic waves and convert them into visible light, the fluorescent lamps can emit various colors.

Although fluorescent lamps have better luminous efficiency than incandescent lamps, due to the inclusion of mercury vapor, in the modern society that advocates environmental protection and energy conservation, people are still thinking about developing new energy-saving and environmentally-friendly lighting devices to replace fluorescent light. Lights, and therefore, LED lighting modules have been developed and placed high hopes. Under a proper forward bias, the electrons and holes are respectively injected into the N and P ends, and then the hole electrons are combined in the P/N interface region to cause the light emitting diode to emit light. This is because the electrons fall back from the high energy state to the low energy state and combine with the hole to release the energy in the form of light.

The light-emitting diode has better luminous efficiency than the fluorescent lamp, and thus the performance in terms of energy saving exceeds that of the fluorescent lamp. However, the application of a lighting device composed of a plurality of single LEDs will increase the cost relatively, so the industry has no efforts to develop lighting devices that use fewer LEDs but still have high luminous efficiency to improve the lighting effect of the LED lighting device.

One aspect of the present invention is provided in a small-sized light-emitting diode lighting device. This LED illumination device provides illumination in a narrow light field and provides efficient illumination.

According to an embodiment of the invention, the LED lighting device comprises a light emitting diode light source and a light guide plate. A light emitting diode source is used to emit light. The light guide plate is adjacent to the light emitting diode light source to receive light. The light guide plate includes a light incident surface, a light exit surface, and a main reflective surface. The light incident surface is adjacent to the light emitting diode light source, so that the light is incident on the light guide plate from the light incident surface. The light incident on the light guide plate exits the light guide plate from the light exit surface. The main reflecting surface is opposite to the light incident surface, wherein the angle between the main reflecting surface and the light emitting surface is substantially equal to 45 degrees to reflect the light incident on the main reflecting surface to the light emitting surface.

According to another embodiment of the present invention, the LED illumination device includes a light emitting diode light source and a light guide plate. A light emitting diode source is used to emit light. The light guide plate is adjacent to the light emitting diode light source to receive light. The light guide plate includes a light incident surface, a light exit surface, and a main reflective surface. The light incident surface is adjacent to the light emitting diode light source, so that the light is incident on the light guide plate from the light incident surface. The light incident on the light guide plate exits the light guide plate from the light exit surface. The main reflecting surface is relative to the light incident surface. The main reflecting surface reflects the light incident on the main reflecting surface to the light emitting surface. The main reflective surface includes a first sub-reflecting surface and a second sub-reflecting surface. The angle between the first sub-reflecting surface and the light-emitting surface is between 38 degrees and 45 degrees. The angle between the second sub-reflecting surface and the light-emitting surface is between 45 degrees and 52 degrees.

As can be seen from the above description, the light-emitting diode lighting device of the embodiment of the present invention reflects light to the light-emitting surface by using a main reflecting surface opposite to the light-incident surface. With the angle of the angle designed by the embodiment of the present invention, the light utilization efficiency of the LED illumination device can be significantly improved, and illumination light providing a narrow light field is provided.

Please refer to FIG. 1 , which is a cross-sectional structural diagram of a light-emitting diode lighting device 100 according to an embodiment of the invention. The light-emitting diode illumination device 100 includes a housing 110, a light-emitting diode light source 120, and a light guide plate 130. The housing 110 is configured to carry the light emitting diode light source 120 and the light guide plate 130 and has a light transmission window 112. The light emitting diode light source 120 is used to provide the light L required for illumination. The light guide plate 130 is configured to guide the light L emitted by the light emitting diode light source 120 such that the light L is emitted from the light transmission window 112 to the outside of the light emitting diode illumination device 100. In the present embodiment, the material of the light guide plate 130 is a photocurable resin, acryl or polymethyl methacrylate (PMMA), but the embodiment of the present invention is not limited thereto.

Please refer to FIG. 1 a , which is a schematic diagram showing the side structure of the light guide plate 130 . The light guide plate 130 includes a light incident surface 132, a light exit surface 134, and a main reflective surface 136. The light incident surface 132 is disposed adjacent to the light emitting diode light source 120 such that the light L of the light emitting diode light source 120 is incident into the light guide plate 130 from the light incident surface 132. The primary reflecting surface 136 is opposite to the light incident surface 132. The main reflecting surface 136 is configured to reflect the light L incident on the main reflecting surface 136 to the light emitting surface 134 so that the light L exits the light guiding plate 130 from the light emitting surface 134. In the present embodiment, the angle θ between the main reflecting surface 136 and the light-emitting surface 134 is substantially equal to 45 degrees, whereby the light L leaving the light guide plate can be distributed in a narrow light field, and the utilization efficiency of the light can be improved.

Please refer to FIG. 2 and FIG. 2a simultaneously. FIG. 2 is a schematic cross-sectional structural view of a light-emitting diode illumination device 200 according to an embodiment of the present invention, and FIG. 2a is a diagram showing a light-emitting diode illumination device 200. Schematic diagram of the side structure of the light plate 230. The light-emitting diode illumination device 200 is similar to the light-emitting diode illumination device 100, except that the light-emitting diode illumination device 200 uses the light guide plate 230 instead of the light guide plate 130.

As shown in FIG. 2a, the light guide plate 230 includes a light incident surface 232, a light exit surface 234, and a main reflective surface 236. The light incident surface 232 is disposed adjacent to the light emitting diode light source 120 such that the light L of the light emitting diode light source 120 is incident from the light incident surface 232 into the light guide plate 230. The primary reflecting surface 236 is opposite the light incident surface 232. The main reflective surface 236 is configured to reflect the light L incident on the main reflective surface 236 to the light exit surface 234 such that the light L exits the light guide plate 130 from the light exit surface 234. In the present embodiment, the primary reflecting surface 236 includes two sub-reflecting surfaces 236a and 236b, and the sub-reflecting surfaces 236a and 236b are adjacent to each other. The angle α between the sub-reflecting surface 236a and the light-emitting surface 234 is between 38 degrees and 45 degrees, and the angle β between the sub-reflecting surface 236b and the light-emitting surface 234 is between 45 degrees. Between 52 degrees. Thereby, the light L leaving the light guide plate can be distributed in a narrow light field, and the utilization efficiency of the light can be improved.

Referring to FIG. 3, the light distribution curve Ct of the conventional illumination device, the light distribution curve C1 of the LED illumination device 100 of the embodiment of the present invention, and the LED illumination device 200 of the embodiment of the present invention are shown. The light distribution curve C2, wherein the vertical axis represents the light intensity, and the horizontal axis represents the angle between the light exiting direction and the normal of the light exit surface of the light guide plate. As can be seen from Fig. 3, the light distribution of the light-emitting diode illumination devices 100 and 200 is concentrated near 0 degrees, and the light intensity near 0 degrees is 6 to 9 times higher than that of the conventional device. More specifically, the main outgoing light field located in the range of 30 degrees or less to -30 degrees or more in the normal direction of the light-emitting surface 234 has a large light intensity, and the normal direction of the light-emitting surface is between 30 degrees and 90 degrees. The light field to be emitted between -30 degrees and -90 degrees has a small light intensity. Therefore, the light-emitting diode lighting devices 100 and 200 of the embodiments of the present invention can provide a narrow light field and high intensity illumination light.

Please refer to FIG. 4 , which is a cross-sectional structural diagram of a light-emitting diode lighting device 400 according to an embodiment of the invention. The light-emitting diode illumination device 400 is similar to the light-emitting diode illumination device 100, but the difference is that the light-emitting diode illumination device 400 further has a reflection device 410. The reflecting device 410 is disposed between the light guide plate 130 and the housing 110. More specifically, the reflecting device 410 is disposed on the auxiliary reflecting surface 138 of the light guide plate 130 , wherein the auxiliary reflecting surface 138 is opposite to the light emitting surface 134 .

In the present embodiment, the reflecting device 410 may be a reflective coating applied to the housing 110 or a reflective plate made of a light reflecting material. The light emitting diode lighting device 400 of the present embodiment is provided by the arrangement of the reflecting device 410 The light utilization efficiency can be further improved.

Please refer to FIG. 5 and FIG. 5a simultaneously. FIG. 5 is a cross-sectional structural diagram of a light-emitting diode illumination device 500 according to an embodiment of the present invention, and FIG. 5a is a cross-sectional view of the reflection device 510 of the illumination device 500. Schematic. The light-emitting diode illumination device 500 is similar to the light-emitting diode illumination device 400, except that the light-emitting diode illumination device 500 uses a reflection device 510 instead of the reflection device 410. The reflecting device 510 includes a plurality of bumps 512 having a triangular cross section, and the bumps 512 are attached to the auxiliary reflecting surface 138 of the light guide plate 130. Bump 512 includes bump surfaces 512a and 512b. The bump surface 512a is adjacent to the auxiliary reflective surface 138 with an angle r1 therebetween between 3 and 20 degrees. The bump surface 512b is adjacent to the auxiliary reflective surface 138 and the bump surface 512a. The angle r2 between the bump surface 512b and the bump surface 512a is between 115 degrees and 135 degrees. The angle r3 between the bump surface 512b and the auxiliary reflective surface 138 is between 40 and 50 degrees.

With the above angle design, the reflecting device 510 can reflect the light incident on the auxiliary reflecting surface 138 to the light emitting surface 134, so that the light emitting diode illumination device 500 can provide a narrow light field and high intensity illumination light.

While the invention has been described above in terms of several embodiments, it is not intended to limit the scope of the invention, and the invention may be practiced in various embodiments without departing from the spirit and scope of the invention. The scope of protection of the present invention is defined by the scope of the appended claims.

100‧‧‧Lighting diode lighting device

110‧‧‧shell

112‧‧‧Light window

120‧‧‧Lighting diode source

130‧‧‧Light guide plate

132‧‧‧Into the glossy surface

134‧‧‧Glossy surface

136‧‧‧ main reflective surface

138‧‧‧Auxiliary reflective surface

200‧‧‧Lighting diode lighting device

230‧‧‧Light guide plate

232‧‧‧Into the glossy surface

234‧‧‧Glossy

236‧‧‧ main reflective surface

236a‧‧‧Sub-reflecting surface

236b‧‧‧Sub-reflecting surface

400‧‧‧Lighting diode lighting device

410‧‧‧Reflecting device

500‧‧‧Lighting diode lighting device

510‧‧‧Reflecting device

512‧‧‧Bumps

512a‧‧‧Bump surface

512b‧‧‧Bump surface

C1, C2, Ct‧‧‧ light distribution curve

R1, r2, r3‧‧‧ angle

L‧‧‧Light

α, β, θ‧‧‧ angle

The above and other objects, features, and advantages of the present invention will become more apparent and understood. A schematic cross-sectional view of a light-emitting diode lighting device according to an embodiment of the invention.

FIG. 1a is a schematic view showing the side structure of a light guide plate according to an embodiment of the invention.

2 is a schematic cross-sectional view showing a lighting diode lighting device according to an embodiment of the invention.

2A is a side view showing the structure of a light guide plate of a light-emitting diode lighting device according to an embodiment of the invention.

Figure 3 is a diagram showing the light distribution curve of a conventional illumination device and the light distribution curve of the light-emitting diode illumination device of the embodiment of the present invention.

4 is a cross-sectional structural view showing a light-emitting diode lighting device according to an embodiment of the present invention.

FIG. 5 is a schematic cross-sectional view showing a light-emitting diode lighting device according to an embodiment of the invention.

FIG. 5a is a schematic cross-sectional view showing a light-emitting diode lighting device according to an embodiment of the invention.

100. . . Light-emitting diode lighting device

110. . . case

112. . . Light transmission window

120. . . Light-emitting diode source

130. . . Light guide

Claims (6)

A light-emitting diode lighting device comprising: a light-emitting diode light source for emitting a light; and a light guide plate adjacent to the light-emitting diode light source for receiving the light, wherein the light guide plate comprises: a light incident surface adjacent to the light emitting diode light source, such that the light is incident from the light incident surface to the light guide plate; a light exiting surface, wherein the light incident into the light guide plate is separated from the light exiting surface The light guiding plate; and a main reflecting surface, the main reflecting surface includes a first sub-reflecting surface and a second sub-reflecting surface, the first sub-reflecting surface is adjacent to the second sub-reflecting surface And the angle between the first sub-reflecting surface and the light-emitting surface is different from the angle between the second sub-reflecting surface and the light-emitting surface. The illuminating diode illuminating device of claim 1, further comprising a reflecting device disposed on an auxiliary reflecting surface of the light guiding plate, wherein the auxiliary reflecting surface is opposite to the light emitting surface, and the reflecting The device reflects the light incident on the auxiliary reflecting surface to the light exiting surface. The illuminating diode illuminating device of claim 2, wherein the reflecting device has a plurality of bumps, wherein each of the bumps comprises: a first bump surface adjacent to the auxiliary reflecting surface, Wherein the angle between the first bump surface and the auxiliary reflective surface is between 3 degrees and 20 degrees; And a second bump surface adjacent to the first bump surface and the auxiliary reflective surface, wherein an angle between the second bump surface and the first bump surface is between 115 degrees and 135 degrees, and The angle between the second bump surface and the auxiliary reflective surface is between 40 degrees and 50 degrees. The illuminating diode illuminating device of claim 2, wherein the reflecting device is made of a light reflecting material. The illuminating diode illuminating device of claim 1, wherein the angle between the first sub-reflecting surface and the illuminating surface is between 38 degrees and 45 degrees, and the second sub-reflecting surface and the light-emitting surface The angle between the faces is between 45 and 52 degrees. The illuminating diode illuminating device of claim 1, wherein the main reflecting surface of the light guiding plate is configured to reflect the light incident on the main reflecting surface to the illuminating surface, and to leave the illuminating surface The intensity of one of the main outgoing light fields is greater than the intensity of the first outgoing light field, wherein the main outgoing light field is located within a range of 30 degrees or less to -30 degrees or more in the normal direction of the light emitting surface, and the secondary outgoing light field It is between 30 degrees and 90 degrees in the normal direction of the illuminating surface and between -30 degrees and -90 degrees in the normal direction.