KR20070018655A - Illumination system and illumination module thereof - Google Patents

Abstract

The light emitting module includes a plurality of LEDs and control circuits, each of which forms a beam of a unique color, and a control circuit electrically connected to the LEDs allows a specific switching speed and The LEDs are periodically switched between the LEDs to emit light in the switching order. The light emitting system includes a plurality of the above-described light emitting modules and control circuits electrically connected to the light emitting modules. The control circuitry periodically switches the LEDs between the LEDs to emit light at a particular switching speed and switching order.

Light emitting module, switching, light guide element, deformation part, prism array, diffraction element, reflective element, switching speed, switching order

Description

Light Emitting System and Light Emitting Module {ILLUMINATION SYSTEM AND ILLUMINATION MODULE THEREOF}

1 shows a first embodiment of a light emitting module according to the invention.

2 shows a second embodiment of a light emitting module according to the invention.

3 shows a third embodiment of a light emitting module according to the invention.

4 shows another example of the third embodiment.

5 shows another example of the third embodiment.

6 shows an embodiment of a light emitting system according to the invention.

This application claims priority to Taiwan Patent Application No. 094126999, filed August 9, 2005.

The present invention relates to a light emitting system and a light emitting module of the system, and more particularly to a light emitting system and a light emitting module of the system using the LED.

Most conventional LCDs use multiple light emitting units that generate light spots to form an image on a display. All light emitting units contain LEDs configured to emit beams of a particular color.

U. S. Patent No. 6,536, 914 discloses a light emitting system used in LCDs. The light emitting system includes a light emitting panel having a light emitting window and at least one edge surface for coupling light to the light emitting panel. The light emitting system further includes a light mixing chamber disposed beside the edge surface to provide a light source. The light source comprises a plurality of LED clusters with different emission wavelengths, for example blue LEDs, green LEDs, red LEDs, or even amber LEDs to provide a uniform light distribution. Can be.

The luminous system saves more power than traditional CRT monitors, but each LED cluster continues to glow when the LCD is powered on. Therefore, a significant amount of light emission continues to be consumed, especially when the light emitting system is applied to medium or large size LCDs. In addition, the light emission of suspended LEDs causes the LCD to overheat, affecting the lifetime. Therefore, a low power consumption light emitting module is urgently needed in the industry.

It is an object of the present invention to provide a light emitting module comprising a first LED, a second LED, a third LED and a control circuit. The first LED is configured to generate a first beam of a first color, the second LED is configured to generate a second beam of a second color, and the third LED generates a third beam of a third color. It is configured to. The control circuit is electrically connected to the first LED, the second LED, and the third LED, and the predetermined switching to mix the first beam, the second beam, and the third beam such that light of a specific color is visually generated. And periodically switch between the first LED, the second LED, and the third LED to emit light in speed and switching order. The light emitting module has the advantages of power saving, low heat, and high luminous efficiency.

The switching sequence is (1) the first LED light emitting; (2) second LED light emission; (3) third LED light emission; And (4) the first, second, and third LEDs simultaneously emit light.

The light emitting module may further include a fourth LED generating a fourth beam of a fourth color. The first, second, third and fourth beams are mixed to visually form light of a particular color. The switching order includes (1) first LED light emission; (2) second LED light emission; (3) third LED light emission; (4) fourth LED light emission; And (5) simultaneous light emission of the first, second, third, and fourth LEDs.

Yet another aspect of the present invention is to provide a light emitting system including a plurality of light emitting modules and a control circuit. Each of the plurality of light emitting modules includes a first LED, a second LED, and a third LED. The first LED is configured to generate a first beam of a first color, the second LED is configured to generate a second beam of a second color, and the third LED generates a third beam of a third color. And the first beam, the second beam, and the third beam are mixed to visually form light of a particular color. The control circuit is electrically connected to the plurality of light emitting modules described above, and periodically switches them between the plurality of light emitting modules so that light of the light emitting system emits light at a predetermined switching speed and switching order so that the light emission of the light emitting system looks like a one-piece large light source. Is configured to. The light emitting system has the advantages of power saving, low heat, and high luminous efficiency.

The detailed description and the preferred embodiment for implementing the invention are described below in conjunction with the accompanying drawings to enable those skilled in the art to better understand the features of the claimed invention.

A preferred embodiment of the present invention is a light emitting module 1 suitable for a backlight module of an LCD as shown in FIG. The backlight module includes an array composed of a plurality of light emitting modules 1. Each of the light emitting modules 1 generates a light spot, that is, an optical pixel. The light pixels form an image.

The light emitting module 1 includes a first LED 101 generating a first beam 100 of a first color, a second LED 103 generating a second beam 102 of a second color, and a third color. A third LED 105 generating a third beam 104, and a control circuit 107. The control circuit 107 electrically connected to the first LED 101, the second LED 103, and the third LED 105 allows the first LED 101, the second LED to emit light at a specific switching speed and switching order. 103, configured to periodically switch between the third LEDs 105.

The light emitting module 1 further comprises a light guide element 109. The first beam 100, the second beam 102, and the third beam 104 are visually mixed into the light 106 of a particular color in the light guide element 109. The light guide element 109 includes a first side 111, a second side 113, a third side 115, and a fourth side 117. The first LED 101, the second LED 103, and the third LED 105 are disposed on the first side 111. The second side 113 and the third side 115 are mirrors for reflecting the first beam 100, the second beam 102, and the third beam 104, ie for reflecting light 106. to be. The fourth side 117 of the light emitting module 1 is a light exit. The light 106 reflected by the second side 113 and the third side 115 is emitted from the fourth side 117 to form the light spot described above.

In this embodiment, the first color is red, the second color is green, and the third color is blue. The switching order controlled by the control circuit 107 is as follows: (1) first LED 101 light emission; (2) emitting the second LED 103; (3) light emitting a third LED 105; And (4) simultaneous light emission of the first LED 101, the second LED 103, and the third LED 105. Each LED does not always emit light, thus saving power. For example, during one switching period, the embodiment saves about 50% power, unlike the backlight module without LED switching for light emission. Further, the light emitting module 1 is made of a semiconductor material whose efficiency decreases at high temperatures, so that switching of each of the LEDs for light emission can be maintained at a relatively low temperature, thus maintaining the high efficiency of the semiconductor material. Thus, the embodiment not only saves power but also has the advantages of low heat and high luminous efficiency.

When white light 106 is required to be generated by the light emitting module 1, the first LED 101, the second LED 103, and the third LED 105 each have a first beam having an appropriate saturation degree. 100, the second beam 102, and the third beam 104 may be generated and visually mixed into white light. However, if the switching speed is too slow, i.e. not faster than the highest speed that the human eye can distinguish, the visible color of the light during the aforementioned switching sequence is (1) red; (2) green; (3) blue; And (4) white, and not always white. Therefore, the switching speed must be faster than the fastest human can distinguish. It is especially preferable not to be slower than 1/120 of 1 second. That is, unless the switching speed is slower than 1/120 of a second, the human eye continues to see light white during the switching period.

In general, the red beam, green beam, and blue beam can be mixed to be visually any color of light. However, with current technology, the brightness of a green or blue LED is higher than that of a red LED. This luminance difference causes color deviation of the mixed light. Another embodiment of the present invention for recovering insufficient brightness of a red LED is shown in FIG. 2. Unlike the light emitting module 1, the light emitting module 2 (control circuit 107 not shown) further includes a fourth LED 201 generating a fourth beam 200 of a fourth color. The first beam 100, the second beam 102, the third beam 104 and the fourth beam 200 are visually mixed with light 202 of a particular color. The fourth color is yellow, restoring insufficient brightness of the first LED 101.

In this embodiment, the switching order of the LEDs is as follows: (1) emitting the first LED 101; (2) emitting the second LED 103; (3) light emitting a third LED 105; (4) emitting fourth LED 201; And (5) simultaneous light emission of the first LED 101, the second LED 103, the third LED 105, and the fourth LED 201. Similarly, each LED does not always emit light, thus saving power. For example, during one switching period, the embodiment saves about 60% power, unlike the backlight module without LED switching for light emission. The embodiment also has the advantage of low heat as described above.

Although the light exits of the above-described embodiment are all disposed on the fourth side 117 of the light guide element 109, the light emitting module of the present invention can change the position of the light exit as required. 3 shows another embodiment of the invention as a light emitting module. The light emitting module 3 includes a first LED 101, a second LED 103, a third LED 105, a fourth LED 201, and a control circuit (not shown). As described above, the LEDs 101, 103, 105, and 201 include a first beam 100 of a first color, a second beam 102 of a second color, a third beam 104 of a third color, and And generate fourth beams 200 of a fourth color, respectively. They may also be mixed to visually form light 300 of a particular color.

The light emitting module 3 also includes a light guide element 301, which has a first side 303, a second side 305, a third side 307, and a fourth side 309. LEDs 101, 103, 105, and 201 are disposed on the first side 303. The difference from the light guide element 109 of the light emitting module 1; 2 is that the light exit of the light emitting module 3 is arranged on the third side 307. Therefore, the light 300 of the light guide element 301 is directed to the third side 307 for light emission.

In order to guide the light 300 to emit light at the third side 307, there is a deformation (not shown) on the second side 305 of the light guiding element 301, which is etched, scribed It may be formed by ice or sandblasting. The deformable portion reflects the beams 100, 102, 104, 200 emitted onto the second side 305 to the third side 307 of the light guide element 301.

In addition to using the deformable portion, the light emitting module 3 may include a diffractive element 401 disposed on the second side 305 of the light guide element 301 as shown in FIG. 4. Diffractive element 401 reflects first beam 100, second beam 102, and third beam 104, and fourth beam 200 to third side 307.

Due to the material of the diffractive element 401, the diffractive element 401 may not be able to fully reflect the beams 100, 102, 104, 200 to the third side 307. This means that a portion of the beams 100, 102, 104, 200 pass through the diffractive element 401. In order to increase the efficiency of reflection, the light emitting module 3 may further comprise a reflective element 403 disposed on the other side of the diffractive element 401, opposite the light guide element 301, ie the reflection Element 403 is disposed below diffractive element 401. The reflective element 403 may reflect a portion of the beams 100, 102, 104, 200 refracted through the diffractive element 401 back to the third side 307 of the light guide element 301. Diffraction element 401 may be a grating or may be composed of other elements having the function of diffraction.

The prism array 501 may also be arranged on the third side 307 of the light emitting module 3 as shown in FIG. 5 to control the angle of occurrence of light 300.

The light exit of the above-described embodiment may simply be on one side, on the third or fourth side, but the present invention does not limit the number of light exits. For example, the light exits may be arranged on the third side and the fourth side such that there are two light exits in one light emitting module. Therefore, the present invention has a number of light exits on different sides and therefore has the advantage of meeting the needs of practical use.

The invention also provides a light emitting system, LCD having a backlight module comprising an array of a plurality of light emitting modules. Each light emitting module generates an optical pixel. The light pixels form an array that shows an image. One embodiment of the present invention is shown in FIG. For simplicity, only two light emitting modules 601 and 603 are shown. The light emitting modules 601 and 603 may include a first LED 605 generating a first beam 600 of a first color, a second LED 607 generating a second beam 602 of a second color, and A third LED 609 for generating a third beam 604 of a third color. The first beam 600, the second beam 602, and the third beam 604 are mixed with light 606 of a particular color. The embodiment further includes a control circuit 611. The control circuit is electrically connected to the light emitting modules 601 and 603 and is configured to periodically switch between the light emitting modules 601 and 603 to emit light at a predetermined switching speed and switching order which provides power savings and low heat. . The light emitting modules 601 and 603 may be one of those shown in FIGS. 1 to 5.

If the switching speed is too slow, i.e. not faster than the human eye can distinguish, the human eye emits light that is not a linear or planar light source formed by a plurality of point light sources generated by the light emitting module. It can be identified that the module emits light sequentially in the switching period. Therefore, the switching speed must be faster than the fastest speed that the human eye can distinguish. The switching speed is preferably no slower than 1/120 of 1 second. That is, the slowest switching speed is 1/120 of 1 second.

Although the embodiment shown in FIG. 6 shows only two light emitting modules, one skilled in the art can easily infer an embodiment with two or more lighting modules. For example, eight light emitting modules can be regarded as one unit in the LCD, and the light emission order of each unit is controlled by one control circuit.

In practice, since the mold for manufacturing the above-mentioned light emitting module is smaller than the mold for manufacturing the large light source, the light emitting system of the present invention, a large light source composed of many light emitting modules, does not need to form a large mold. Therefore, the cost is reduced.

Although the above description uses LCD as an example, the present invention does not limit the field. For example, those skilled in the art can apply the light emitting module of the present invention to a projector, including a front projector and a rear projector, or other display devices as described above. Thus, the light emitting system of the present invention may be a projector or other display device.

The foregoing is directed to detailed technical content and features of the invention. Those skilled in the art may make various modifications and substitutions based on the above disclosures and suggestions without departing from the features of the present invention. Nevertheless, while the foregoing modifications and substitutions are not fully disclosed in the detailed description, they are substantially covered by the following appended claims.

The light emitting system including the light emitting module and the light emitting module of the present invention uses a control circuit to periodically emit the light emitting module so that the light emitting module emits light at a specific switching speed and switching order to mix each beam so that light of a specific color is visually generated. It is configured to switch to, and has the advantages of power saving, low heat, and high luminous efficiency.

Claims (26)

In the light emitting module, A first LED generating a first beam of a first color; A second LED generating a second beam of a second color; A third LED generating a third beam of a third color; And Including a control circuit, The control circuit is electrically connected to the first LED, the second LED, and the third LED, and specific switching to mix the first beam, the second beam, and the third beam such that light of a specific color is visually generated. And periodically switching between the first LED, the second LED, and the third LED to emit light in speed and switching order. The light emitting module of claim 1, wherein the switching speed is not slower than 1/120 of 1 second. The method of claim 1, wherein the switching order is (1) first LED light emission; (2) second LED light emission; (3) third LED light emission; And (4) the first, second, and third LEDs simultaneously emit light; The light emitting module of claim 1, wherein the first color is red, the second color is green, and the third color is blue. The light emitting module of claim 4, wherein the specific color is white. The apparatus of claim 4, further comprising a fourth LED generating a fourth beam of a fourth color, wherein the first, second, third, and fourth beams are mixed to visually form light. Light emitting module, characterized in that. The light emitting module of claim 6, wherein the fourth color is yellow. The method of claim 6, wherein the switching order is (1) first LED light emission; (2) second LED light emission; (3) third LED light emission; (4) fourth LED light emission; And (5) the first, second, third, and fourth LEDs simultaneously emit light; The light emitting module of claim 7, wherein the specific color is white. Further comprising: a light guiding element for guiding light, the light guiding element comprising a first side, and wherein the first LED, the second LED, and the third LED are on the first side. Light emitting module, characterized in that disposed. 11. The apparatus of claim 10, further comprising a diffractive element and a reflective element, the light guide element further comprising a second side, the diffractive element disposed on the second side and the reflective element opposite the light guide element. Light emitting module, wherein the light emitting module is arranged on another side of the diffractive element. 11. The light emitting module of claim 10, wherein said light guide element further comprises a second side having a deformable portion. 11. The light emitting module of claim 10, further comprising a prism array, the light guide element further comprising a third side, wherein the prism array is disposed on the third side. In the light emitting system, A plurality of light emitting modules, each of the plurality of light emitting modules A first LED generating a first beam of a first color; A second LED generating a second beam of a second color; A third LED generating a third beam of a third color; And Including a control circuit, The first beam, the second beam, and the third beam are visually mixed into specific light, And the control circuit is electrically connected to the plurality of light emitting modules, and periodically switches between the plurality of light emitting modules such that the plurality of light emitting modules emit light at a specific switching speed and switching order. 15. The light emitting system of claim 14, wherein said switching speed is no slower than 1/120 of a second. The light emitting system of claim 14, wherein the first color is red, the second color is green, and the third color is blue. 17. The light emitting system of claim 16, wherein said specific color is white. The method of claim 16, wherein each of the plurality of light emitting modules further comprises a fourth LED generating a fourth beam of a fourth color, wherein the first beam, the second beam, the third beam, and the fourth beam emit light. Light-emitting system, characterized in that it is mixed to form a visual. 19. The light emitting system of claim 18, wherein said fourth color is yellow. 20. The light emitting system of claim 19, wherein said specific color is white. 15. The apparatus of claim 14, wherein each of the plurality of light emitting modules further comprises a light guiding element for guiding light, the light guiding element comprising a first side, the first LED, a second LED, and a third LED. Is disposed on the first side. The light emitting device of claim 21, wherein each of the plurality of light emitting modules further comprises a diffractive element and a reflective element, the light guide element further comprising a second side, the diffractive element disposed on the second side and the reflecting Wherein the element is disposed on another side of the diffractive element opposite the light guide element. The light emitting system of claim 21, wherein said light guide element further comprises a second side having a deformation. 22. The method of claim 21, wherein each of the plurality of light emitting modules further comprises a prism array, the light guide element further comprising a third side, wherein the prism array is disposed on the third side. Luminous system. The light emitting system of claim 14, wherein said light emitting system is an LCD. 15. The light emitting system of claim 14, wherein said light emitting system is a projector.

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