Color LED display device without color separation

A color LED display device without color separation comprises a substrate, a plurality of display units, a power supply unit, and a control unit. Each display unit comprises a driving chip, at least one red-light LED chip, at least one green-light LED chip, at least one blue-light LED chip, and a micro optical device assembly. The micro optical device assembly is disposed above the red-light, green-light and blue-light LED chips. When the control unit controls the display unit to emit light, the red-light, green-light and blue-light LED chips emit red, green and blue lights respectively and simultaneously. The red, green and blue lights pass through the micro optical device assembly, such that the light paths of the red, green and blue lights are changed and the three lights are combined on a two-dimensional plane. Therefore, the color separation phenomenon of the conventional color LED display device is solved.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims foreign priority from a Taiwan Patent Application, Ser. No. 100108313, filed on Mar. 11, 2011.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a color LED display device, in particular to the color LED display device using a micro optical device assembly to change a light path, such that red light, green light and blue light can be combined onto a two-dimensional plane to improve the color separation phenomenon.

2. Description of the Related Art

In recent years, light emitting diode (LED) is used extensively in LED illumination device, LED display device and LED backlight module, wherein the LED display device is commonly used in advertising billboards and traffic indicating devices. With reference toFIG. 1for the architecture of a conventional monochrome LED display device, the conventional monochrome LED display device10′ generally comprises a main frame109′, at least one display module105′, at least one cable106′, at least one connector107′, and at least one main control module108′, wherein the conventional monochrome LED display device10′ as shown inFIG. 1has three display modules105′ and two connectors107′, and the display module105′ has a plurality of monochrome LED components1051′. The cable106′ is electrically coupled to the three display modules105′ and the main control module108′. The main control module108′ comprises a control unit1081′ and a power supply unit1082′, wherein the power supply unit1082′ can supply a power source to the LED component1051′; the control unit1081′ can control all LED components1051′ to emit light or turn off. Therefore, the display module105′ can display specific numbers, graphics or texts.

Since the monochrome LED display device cannot display color numbers, graphics or texts, therefore LED display device manufacturers introduce a color LED display device. With reference toFIG. 2for a perspective view of a conventional color LED display device, the conventional color LED display device1acomprises: a substrate10a, a flexible circuit board30aand a plurality of LED display units20a, wherein the substrate10aincludes two power supply holes11a.

With reference toFIG. 3for a perspective view of an LED display unit of a conventional color LED display device, the LED display unit20afurther comprises: a casing201a, a driving chip202a, a green light LED chip203a, a red light LED chip204a, and a blue light LED chip205a, wherein the green light LED chip203a, the red light LED chip204aand the blue light LED chip205aare coupled to the driving chip202a, and represent pixel respectively. The green light LED chip203a, the red light LED chip204aand the blue light LED chip205aare driven by the driving chip202ato emit light. InFIG. 2, when a portion or all of the LED display units20aemit light, the conventional color LED display device1acan display color numbers, graphics or texts.

With reference toFIG. 4for a cross-sectional side view of the conventional color LED display device, the conventional color LED display device1acomes with a simple structure and a low manufacturing cost. However, the display unit20aas shown inFIG. 4does not have other optical components such as the refractive lens, so that when the driving chip202adrives the green light LED chip203a, the red light LED chip204aand the blue light LED chip205ain the display unit20ato emit light, a green light G′, a red light R′ and a blue light B′ will not be refracted by emitted directly from the display unit20a, and the green light G′, the red light R′ and the blue light B′ cannot be combined on a two-dimensional plane. As a result, when a user views the images at a near distance, the user will see the three separated color lights of the conventional color LED display device1a. In other words, the conventional color LED display device1ahas the drawback of the color separation phenomenon.

In addition the light emission of the LED chip will generate heat, so that the distance between the green light LED chip203a, the red light LED chip204aand the blue light LED chip205aof the conventional color LED display device1ais generally too short, and the distance between two adjacent LED chips must be over 0.2 mm, and thus the method of reducing the distance between the LED chips in order to overcome the color separation problem of the conventional color LED display device1acannot be used.

In view of the aforementioned problems of the conventional monochrome LED display device and color LED display device that cannot display color numbers, graphics or texts and having the color separation phenomenon, the inventor of the present invention conducted extensive researches and experiments, and finally developed a color LED display device without color separation in accordance with the present invention to overcome the drawbacks of the prior art.

SUMMARY OF THE INVENTION

Therefore, it is a primary objective of the present invention to provide a color LED display device without color separation, wherein a micro optical device assembly is installed above the red-light LED chip, the green-light LED chip and the blue-light LED chip in the display unit and provided for refracting and changing the light paths of the red light, the green light and the blue light to further combine the three color lights onto a two-dimensional plane, so as to improve the color separation phenomenon of the conventional color LED display device.

To achieve the foregoing objective, the inventor of the present invention provides a color LED display device without color separation, comprising:

a substrate, having a plurality of conductive wires laid thereon;

a plurality of display units, arranged in form of an array on the substrate, and coupled to the plurality of conductive wires, and each display unit comprising:

a driving chip;

at least one red-light LED chip, coupled to the driving chip for emitting a red light;

at least one green-light LED chip, coupled to the driving chip for emitting a green light;

at least one blue-light LED chip, coupled to the driving chip for emitting a blue light; anda micro optical device assembly, installed above the red-light LED chip, the green-light LED chip and the blue-light LED chip;

a power supply unit, coupled to the substrate, for supplying a power source to the plurality of display units; and

a control unit, coupled to substrate, for controlling the plurality of display units to emit light;

thereby, when the control unit controls the display unit to emit light, the red-light LED chip, the green-light LED chip and the blue-light LED chip emit red light, green light and blue light simultaneously, and the red light, the green light and the blue light pass through the micro optical device assembly to change their light paths, and the red light, the green light and the blue light are combined on a two-dimensional plane.

Another objective of the present invention is to provide a color LED display device without color separation, wherein a micro optical device assembly is installed above the red-light LED chip, the green-light LED chip and the blue-light LED chip in the display unit and a directional optical device assembly is installed above the display unit, and the micro optical device assembly is provided for refracting and changing the light paths of the red light, the green light and the blue light to further combine the three color lights onto a two-dimensional plane, so as to improve the color separation phenomenon of the conventional color LED display device. In the meantime, the directional optical device assembly can display 3D images from the color LED display device.

To achieve the aforementioned objective, the inventor of the present invention provides a color LED display device without color separation, comprising:

a substrate, having a plurality of conductive circuits laid thereon;

a plurality of display units, arranged in form of an array on the substrate, and coupled to the plurality of conductive circuits, and each display unit comprising:

a driving chip;

at least one red-light LED chip, coupled to the driving chip for emitting a red light;

at least one green-light LED chip, coupled to the driving chip for emitting a green light;

at least one blue-light LED chip, coupled to the driving chip for emitting a blue light; and

a micro optical device assembly, installed above the red-light LED chip, the green-light LED chip and the blue-light LED chip;

a power supply unit, coupled to the substrate, for supplying a power source to the plurality of display units;

a control unit, coupled to substrate, for controlling the plurality of display units to emit light; and

a directional optical device assembly, installed above the plurality of display units;

thereby, when the control unit controls the display unit to emit light, the red-light LED chip, the green-light LED chip and the blue-light LED chip emit red light, green light and blue light simultaneously, and the red light, the green light and the blue light pass through the micro optical device assembly and change their light paths, and the red light, the green light and the blue light are combined on a two-dimensional plane and emitted from the directional optical device assembly to the outside, and the red light, the green light and the blue light emitted from the directional optical device assembly produce an effect of a 3D image to naked eyes.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The technical content of the color LED display device without color separation in accordance with the present invention will become apparent with the detailed description of the following preferred embodiments accompanied with the illustration of related drawings as follows.

With reference toFIG. 5for the main architecture of a color LED display device without color separation in accordance with a first preferred embodiment of the present invention, the color LED display device without color separation1comprises: a substrate11, a plurality of display units12, a power supply unit13, and a control unit14. The substrate11is a circuit board having a plurality of conductive wires111installed on a surface of the circuit board.

With reference toFIG. 6for the perspective view of a display unit of a color LED display device without color separation in accordance with the first preferred embodiment of the present invention together withFIG. 5, the plural display units12are arranged in form of an array on the substrate11and coupled to the plurality of conductive wires111. Each display unit12comprises: a driving chip121; a red-light LED chip122, coupled to the driving chip121for emitting a red light R; a green-light LED chip123, coupled to the driving chip121for emitting a green light G; a blue-light LED chip124, coupled to the driving chip121for emitting a blue light B; and a micro optical device assembly125, installed above the red-light LED chip122, the green-light LED chip123and the blue-light LED chip124. In addition, the display unit12further comprises a casing120for containing the driving chip121, the red-light LED chip122, green-light LED chip123, blue-light LED chip124, and micro optical device assembly125. In general, the common light emitting chips include LED chips and OLED chips, and the LED chips and the OLED chips can be adopted in the first preferred embodiment of the color LED display device without color separation1to serve as the red-light LED chip122, the green-light LED chip123and the blue-light LED chip124.

The power supply unit13is coupled to the substrate11for supplying a power source to the plurality of display units12. InFIG. 5, the power supply unit13is a power connector. For the color LED display device without color separation1of the present invention, the power supply unit13is not limited to the power connector only, but it can also be a battery or a power supply device. The control unit14is coupled to substrate11for controlling the plurality of display units12to emit light, wherein the control unit14can be a computer, an input device or a handwriting input device. In addition, the control unit14further comprises a memory card access device141for plugging in a memory card M. Therefore, a user can use the control unit14to input graphics, numbers, or texts and display them from the color LED display device without color separation1. Users can selectively save the inputted graphics, numbers, or texts in the memory card through the memory card access device141.

With referenceFIG. 7for a cross-sectional side view of a color LED display device without color separation in accordance with the first preferred embodiment of the present invention together withFIGS. 5 and 6, the micro optical device assembly125installed above the red-light LED chip122, the green-light LED chip123and the blue-light LED chip124is a bi-convex lens. In addition, the side facing the red-light LED chip122, the green-light LED chip123and the blue-light LED chip124is formed by three secondary plano-convex lenses, and the other side is a primary plano-convex lens.

With reference toFIGS. 5 and 6, when the control unit14controls the display unit12to emit light, the red-light LED chip122, the green-light LED chip123and the blue-light LED chip124will emit red light R, green light G and blue light B simultaneously. Now, the red light R, the green light G and the blue light B will pass through the micro optical device assembly125to change their light paths as shown inFIG. 7, and finally the red light R, the green light G and the blue light B will be combined on a two-dimensional plane. Therefore, even when a user views the color LED display device without color separation1, the user will not see the three separated color lights. In other words, the color LED display device without color separation1of the present invention does not have the drawback of the color separation phenomenon. To increase the diffraction angle of the light emitted from the display unit12, a diffussing unit16is installed above the plurality of display units12as shown inFIG. 7, and the viewing angle of the color LED display device without color separation1can be extended.

In addition, the present invention further provides a second preferred embodiment of the color LED display device without color separation which further has the function of displaying 3D images. With reference toFIG. 8for a perspective view of a color LED display device without color separation in accordance with a second preferred embodiment of the present invention together withFIG. 5, basically the color LED display device without color separation1of the second preferred embodiment has the same components of the first preferred embodiment and comprises the substrate11, the plurality of display units12, the power supply unit13, and the control unit14, except that the color LED display device without color separation1of the second preferred embodiment further comprises a directional optical device assembly15installed above the plurality of display units12, wherein the directional optical device assembly15is a micro-cylindrical lens array or a parallax mask.

With reference toFIG. 9for a cross-sectional side view of a color LED display device without color separation in accordance with the second preferred embodiment of the present invention together withFIG. 8, the directional optical device assembly15is a micro-cylindrical lens array. InFIG. 9, when the display unit12emits light, the red-light LED chip122, the green-light LED chip123and the blue-light LED chip124emit the red light R, the green light G and the blue light B simultaneously, and the red light R, the green light G and the blue light B will pass through the micro optical device assembly125to change their light paths, and finally the red light R, the green light G and the blue light B will be combined on a two-dimensional plane and refracted from the micro-cylindrical lens array (or the directional optical device assembly15) and emitted to the outside. Now, the combined light of the red light R, the green light G and the blue light B is received by naked eyes to produce different visual images to the user's left and right eyes, so as to provide a 3D image effect.

With reference toFIGS. 10 and 11for the other perspective view and cross-sectional side view of the color LED display device without color separation in accordance with the second preferred embodiment of the present invention respectively, if the parallax mask is used as the directional optical device assembly15, then when the display unit12emits light, the red light R, the green light G and the blue light B will be combined on the two-dimensional plane, and the parallax mask (or the directional optical device assembly15) will display images alternately. Now, the images alternately displayed by the parallax mask show longitudinal and latitudinal lines to produce the 3D image effect to naked eyes.

In summation of the description of the two preferred embodiments above, the color LED display device without color separation in accordance with the present invention has the following advantages:

1. The color LED display device without color separation of the present invention adds a micro optical device assembly installed above the red-light LED chip, the green-light LED chip and the blue-light LED chip in the display unit and uses the micro optical device assembly to refract and change the light paths of the red light, the green light and the blue light, such that the three color lights are combined on a two-dimensional plane to improve the color separation phenomenon of the conventional color LED display device.
2. Like the conventional color LED display device, the color LED display device without color separation comes with a simple structure and a low manufacturing cost while solving the problem of color separation, and thus the invention can be used extensively in areas such as TV walls, advertising billboards, and marquee displays.
3. The present invention further adds a directional optical device assembly installed above the display unit, such that the color LED display device can display 3D images.