SIDE-EDGE BACKLIGHT MODULE HAVING NON-UNIFORMLY SIZED BACKLIGHT SECTIONS AND DESIGN METHOD THEREOF

Abstract

A side-edge backlight module having non-uniformly sized backlight sections includes backlight sections that have relative sizes satisfying the condition that the backlight sections have higher ranks are of greater sizes. Ranking the backlight sections is made by conducting an simulation operation for a process of sectionalized lighting of backlight to display liquid crystal panel signals on the basis of uniformly sized backlight sections and conducting analysis of the number of zones where an interference signal appears and distance of the interference signal when each of backlight sections is lit in the simulation operation on the basis of uniformly sized backlight sections and ranking the backlight sections according to strength of cross-talking caused by the interference signal so that a backlight section having less strong cross-talking is set with a higher rank.

Claims

1. A side-edge backlight module, comprising a number of backlight sections that are arranged side by side in a first direction to collectively define a planar smooth surface having a lateral edge with interfacing lines between the backlight sections located on the planar surface and substantially perpendicular to the lateral edge, the backlight sections receiving light projecting from the lateral edge in a second direction that is substantially perpendicular to the first direction and parallel to the planar surface, the backlight sections being adapted to correspond to and respectively illuminate sections of a display panel that receive image signals to be displayed with the light projecting from the lateral edge in the second direction, the backlight sections being ranked according to a predetermined rule and having non-uniform sizes such that the sizes of the backlight sections respectively correspond to the ranks of the backlight sections, wherein the rank of each specific one of the backlight sections is determined by strength of an interference signal resulting from cross-talking among the display panel sections when the specific one of the backlight sections is lit so that a backlight section has less strong cross-talking is set with a higher rank and the backlight sections are ranked according to the strengths of cross-talking that the backlight sections exhibit, wherein the sizes of the backlight sections are each variable and determined according to the ranks of the backlight sections.

2. The side-edge backlight module as claimed in claim 1, wherein the number of backlight sections of the side-edge backlight module comprise first, second, third, fourth, and fifth backlight sections, which are grouped into first group that comprises the third backlight section, a second group that comprises the second and fourth backlight section, and a third group that comprises a first and fifth backlight section, where the backlight sections of the groups have non-uniform sizes, among which the third backlight section of the first group has the greatest size, the second and fourth backlight sections of the second group have the second greatest size, and the first and fifth backlight sections of the third group have the third greatest size.

3. The side-edge backlight module as claimed in claim 1, wherein the number of backlight sections of the side-edge backlight module comprise first, second, third, and fourth backlight sections, among which the second backlight section has the greatest size, the first backlight section has the second greatest size, the third backlight section has the third greatest size, and the fourth backlight section has the fourth greatest size.

4. The side-edge backlight module as claimed in claim 1, wherein the side-edge backlight module is of single short edge incidence.

5. The side-edge backlight module as claimed in claim 1, wherein the side-edge backlight module is of dual short edge incidence.

6. A side-edge backlight module, comprising a number of backlight sections that are arranged side by side in a first direction to collectively define a planar smooth surface having a lateral edge with interfacing lines between the backlight sections located on the planar surface and substantially perpendicular to the lateral edge, the backlight sections receiving light projecting from the lateral edge in a second direction that is substantially perpendicular to the first direction and parallel to the planar surface, the backlight sections being adapted to correspond to and respectively illuminate sections of a display panel that receive image signals to be displayed with the light projecting from the lateral edge in the second direction, the backlight sections being ranked according to a predetermined rule and having non-uniform sizes such that the sizes of the backlight sections respectively correspond to the ranks of the backlight sections, wherein the rank of each specific one of the backlight sections is determined by strength of an interference signal resulting from cross-talking among the display panel sections when the specific one of the backlight sections is lit so that a backlight section has less strong cross-talking is set with a higher rank and the backlight sections are ranked according to the strengths of cross-talking that the backlight sections exhibit; wherein the sizes of the backlight sections are each variable and determined according to the ranks of the backlight sections; wherein the number of backlight sections of the side-edge backlight module comprise first, second, third, fourth, and fifth backlight sections, which are grouped into first group that comprises the third backlight section, a second group that comprises the second and fourth backlight section, and a third group that comprises a first and fifth backlight section, where the backlight sections of the groups have non-uniform sizes, among which the third backlight section of the first group has the greatest size, the second and fourth backlight sections of the second group have the second greatest size, and the first and fifth backlight sections of the third group have the third greatest size; and wherein the side-edge backlight module is of single short edge incidence.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The technical solution, as well as beneficial advantages, of the present invention will be apparent from the following detailed description of an embodiment of the present invention, with reference to the attached drawings. In the drawings:

[0030] FIG. 1 is a schematic view showing sectionalized lighting and leakage of a conventional side-edge LED backlight;

[0031] FIGS. 2A and 2B are schematic views illustrating sectionalized backlight lighting of a 46-inch single edge side-edge LED television;

[0032] FIG. 3 is a schematic view showing the sites of 9 points on a display screen for measuring cross-talking;

[0033] FIG. 4 is a schematic view showing timing relationship (for left-eye signal) between backlight sections of a 46-inch single short edge side-edge LED television and liquid crystal panel signals;

[0034] FIGS. 5A and 5B are diagrams illustrating liquid crystal panel signals and backlight scanning timing when the number of backlight sections is odd;

[0035] FIGS. 6A and 6B are diagrams illustrating liquid crystal panel signals and backlight scanning timing when the number of backlight sections is even;

[0036] FIG. 7A is a schematic view illustrating relative sizes of the backlight sections that are of an odd number for a preferred embodiment of the side-edge backlight module having non-uniformly sized backlight sections according to the present invention;

[0037] FIG. 7B is a schematic view illustrating relative sizes of the backlight sections that are of an even number for another preferred embodiment of the side-edge backlight module having non-uniformly sized backlight sections according to the present invention; and

[0038] FIG. 8 is a flow chart illustrating a design method for a side-edge backlight module having non-uniformly sized backlight sections.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] The present invention uses non-uniformly sized backlight sections to improve cross-talking and enhance quality of displaying. Referring to FIG. 8, a flow chart is given to illustrate a design method for a side-edge backlight module having non-uniformly sized backlight sections. The method comprises the following steps:

[0040] Step 1: conducting an simulation operation for a process of sectionalized lighting of backlight to display liquid crystal panel signals on the basis of uniformly sized backlight sections according to predetermined liquid crystal panel signals and backlight scanning timing;

[0041] Step 2: conducting analysis of the number of zones where an interference signal appears and distance of the interference signal when each of backlight sections is lit in the simulation operation on the basis of uniformly sized backlight sections and ranking the backlight sections according to strength of cross-talking caused by the interference signal when each of the backlight sections is lit so that a backlight section having less strong cross-talking is set with a higher rank; and

[0042] Step 3: providing a higher-rank backlight section with a relatively larger size.

[0043] The method is applicable to for example single short edge incidence backlight module or dual short edge incidence backlight module for designing side-edge backlight module having non-uniformly sized backlight sections.

[0044] The design method, as well as a side-edge backlight module having non-uniformly sized backlight sections designed with such a method, will be described with reference to FIGS. 5A, 5B, 6A, 6B, 7A, and 7B.

[0045] FIGS. 5A and 5B are diagrams showing liquid crystal panel signals and backlight scanning timing where the number of backlight sections is odd. As shown in FIG. 5A, the number of sections used is odd and a specific example of four is given. The left-eye and right-eye liquid crystal panel signals are shown sequentially arranged. The ranges of the left-eye and right-eye signals are indicated by braces. As shown in FIG. 5A, the simulation operation is conducted according to Step 1, where when the backlight is lit, lighting can be selected to be constantly maintained at the center of the liquid crystal panel signal in order to minimize cross-talking. For a backlight module that is composed of 2n+1 (n being a natural number) backlight sections, a liquid crystal panel signal that is correspondingly divided into 2n+1 sections. Maintaining lighting at the center of the liquid crystal panel signal means lighting the n+1th section of the liquid crystal panel signal. In this way, the distance from the previous or next interference signal is the greatest, making the cross-talking minimized. As shown in FIG. 5B, during the cycling process of the liquid crystal panel signals, the first, second, and third sections of backlight are lit separately. The location where the backlight section is lit is indicated by hatching. It is noted from the drawing that the locations, as well as the number thereof, where the interference signals occur are different. In other words, the strength of cross-talking so caused is different, leading to asymmetry of cross-talking. The strength of cross-talking is identical when the second and fourth backlight sections are lit and the strength of cross-talking is also identical when the first and fifth backlight sections are lit. Thus, based on the location where the interference signal occurs, the present invention follows Step 2 to rank the backlight sections according to the strength of the interference signal and then follows Step 3 to modify the relative sizes of the backlight sections by decreasing the size of a backlight section that causes a severer interference signal so as to reduce the strength of the interference caused thereby and thus making the displaying quality approaching symmetry. Thus, a side-edge backlight module having non-uniformly sized backlight sections according to the present invention is completed.

[0046] As shown in FIG. 7A, a schematic view is given to illustrate relative sizes of the backlight sections that are of an odd number for a preferred embodiment of the side-edge backlight module having non-uniformly sized backlight sections according to the present invention. In the embodiment, the number of the backlight sections is five. The side-edge backlight module comprises, in sequence, first, second, third, fourth, and fifth backlight sections, and the relative sizes of the backlight sections are modified according to the present invention so that the sizes of the backlight sections are increased from the smallest at the ends to the greatest in the center and are made symmetric in the up-down direction. Among all the backlight sections, the third backlight section has the greatest size, the second and fourth backlight sections have the second greatest size, and the first and fifth backlight sections have the third greatest size. Although the present invention provides only an example of five backlight sections for illustration, yet the same process can be applied to different numbers of backlight sections to make an analysis for determining the relative sizes. A simulation may then be conducted for minor adjustment. Adopting the side-edge backlight module having non-uniformly sized backlight sections according to the present invention and making displaying according to the predetermined liquid crystal panel signals and backlight scanning timing can apparently improve cross-talking and enhance quality of displaying.

[0047] FIGS. 6A and 6B are diagrams showing liquid crystal panel signals and backlight scanning timing where the number of backlight sections is even. As shown in FIG. 6A, the number of sections used is even and a specific example of four is given. The left-eye and right-eye liquid crystal panel signals are shown sequentially arranged. The ranges of the left-eye and right-eye signals are indicated by braces. In FIG. 6A, the sections are of an even number and the location where the backlight section is lit is indicated by hatching. When the backlight is lit, lighting can be selected to be constantly maintained at the second section of the liquid crystal panel signal in order to minimize cross-talking at the center. For a backlight module that is composed of 2n (n being a natural number) backlight sections, lighting of the backlight can be selectively maintained at the nth section of the liquid crystal panel signal, namely being as close to the center of the liquid crystal panel signal as possible, so as to minimize cross-talking at the center. As shown in FIG. 6B, during the cycling process of the liquid crystal panel signals, the locations, as well as the number thereof, where the interference signals occur are different, leading to asymmetry of cross-talking. FIG. 6B shows four different displaying timing (having an even number of sections: four sections), where the first, second, and third sections of backlight are lit separately (the second section being free of interference signal so that the section size can be the greatest). Again, the previously described steps of the present invention are followed to rank the strengths of interference signal occurring when each of the backlight sections is lit in order to modify the relatively sizes of the backlight sections and thus obtaining the relative sizes of the backlight sections shown in FIG. 7B for an even number of backlight sections. In the embodiment, the number of the backlight sections is four, where the side-edge backlight module comprises, in sequence, first, second, third, and fourth backlight sections. Among all the backlight sections, the second backlight section has the greatest size, the first backlight section has the second greatest size, the third backlight section has the third greatest size, and the fourth backlight section has the fourth greatest size.

[0048] In summary, the present invention provides a side-edge backlight module having non-uniformly sized backlight sections and a design method thereof, which use liquid crystal panel signals and backlight scanning timing to determine the influence on cross-talking caused by each of the backlight sections in order to improve cross-talking and enhance displaying quality through modification of the relative sizes of the backlight sections.

[0049] Based on the description given above, those having ordinary skills of the art may easily contemplate various changes and modifications of the technical solution and technical ideas of the present invention and all these changes and modifications are considered within the protection scope of right for the present invention.