DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0033] Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

[0034] FIGS. 3A and 3B are perspective views of exemplary fluorescent lamps of a backlight device according to the present invention. In FIG. 3A, an external electrode fluorescent lamp (EEFL) 31 may have external electrodes 33 and 33a formed at both ends of the EEFL lamp 31, such that light is emitted when a power is applied to the external electrodes 33 and 33a. An insulating layer 32 may partially enclose the external electrodes 33 and 33a.

[0035] In FIG. 3B, a cold cathode fluorescent lamp (CCFL) 31a may have internal electrodes 34 and 34a at both ends of the CCFL lamp 31a, such that light is emitted when a power is applied to the internal electrodes 34 and 34a. In addition, lamp holders 35 and 35a may be formed at both ends of the CCFL lamps 31a for holding the internal electrodes 34 and 34a and the power incoming lines 36 and 36a.

[0036] FIGS. 4A and 4B are perspective views of an exemplary direct-type backlight device according to the present invention, and FIG. 4C is a cross-sectional view of the exemplary backlight device illustrated in FIG. 4B. In FIG. 4A, a backlight device may include a plurality of fluorescent lamps 31 arranged parallel to each other, first and second lower lamp fixing assemblies 41a and 41b arranged facing each other, first and second upper lamp fixing assemblies 43a and 43b arranged facing each other, and conductive layers 47a, 47b, 47c, and 47d formed along sides of the lamp fixing assemblies 41a, 41b, 43a, and 43b. The fluorescent lamps 31 may be EEFL lamps and may have external electrodes 33 and 33a, and insulating layers 32 at both ends thereof.

[0037] In addition, the first and second lower lamp fixing assemblies 41a and 41b may face each other at a predetermined interval to correspond to a length of the fluorescent lamps 31, and may have a plurality of grooves 45 formed along the sides thereof. Further, the first and second upper lamp fixing assemblies 43a and 43b may be arranged at the same predetermined interval as the first and second lower lamp fixing assemblies 41a and 41b, and may have a plurality of grooves 45a formed along the sides thereof to correspond the grooves 45. The grooves 45 and 45a may be formed such that the fluorescent lamps 31 completely penetrate the first and second upper and lower lamp fixing assemblies 43a, 43b, 41a, and 41b. Also, the grooves 45 may accommodate about half of the diameter of the fluorescent lamps 31 and the grooves 45a may accommodate the remaining half of the diameter of the fluorescent lamp 31. Accordingly, the ends of the fluorescent lamps 31 may be securely fixed within the grooves 45 and 45a of the lower and upper lamp fixing assemblies 41a, 41b, 43a, and 43b, as shown in FIG. 4B, thereby making the installment/replacement of the fluorescent lamps 31 easier.

[0038] In addition, as shown in FIG. 4B, the conductive layers 47a, 47b, 47c, and 47d may contact the ends of the fluorescent lamps 31 for applying a power to the fluorescent lamps 31. The conductive layers 47a, 47b, 47c, and 47d may be formed by filling a conductive material inside a trench along the sides of the lower and upper lamp fixing assemblies 41a, 41b, 43a, and 43b. Alternatively, the conductive layers 47a, 47b, 47c, and 47d may be formed by coating a conductive material on a surface of the lower and upper lamp fixing assemblies 41a, 41b, 43a, and 43b. Also, a connector 61 may connect the conductive layers 47a, 47b, 47c, and 47d to a driving circuit (not shown) for driving and supplying a power to the fluorescent lamps 31. Accordingly, the number of connectors used within the backlight device may be reduced and the interconnection between the fluorescent lamps and the driving circuit may be simplified.

[0039] As shown in FIG. 4C, the first and second upper lamp fixing assemblies 43a and 43b may have a tapering width, wherein the width of the surfaces contacting the lower lamp fixing assemblies 41a and 41b may be larger than a width A of the opposing surfaces. For example, the first and second lamp fixing assemblies 43a and 43b may have an inclined angle θ of about 10° to about 30°. Also, the external electrodes 33 and 33a may be partially exposed within an effective luminous area, and the partially exposed portions may have a length X. The length X may depend on the incline angle θ and a height h of the first upper and lower lamp fixing assemblies 43a and 41a or of the second upper and lower lamp fixing assemblies 43b and 41b. For example, the exposed length X of the electrodes 33 and 33a may be within about 35% of the height h of the first and second upper and lower lamp fixing assemblies 43a, 43b, 41a, and 41b, i.e., x≦0.35 h. If the incline angle θ is set at a range of about 20-24°, the length X may correspond to about 20% of the height h, i.e., X=0.2 h. Accordingly, the width A of the first and second upper lamp fixing assemblies 43a and 43b may be reduced and the luminance at both ends of the fluorescent lamps 31 may be enhanced without diminishing quality of image within the effective luminous area.

[0040] Furthermore, the partially exposed portions of the external electrodes 33 and 33a may be covered with the insulating layer 32 to avoid formation of a dark line around ends of the fluorescent lamps 31 caused by oxidization of the external electrodes 33 and 33a. For example, the insulating layer 32 may be made of a white insulating material.

[0041] In FIG. 4C, the backlight device may further include a non-luminous area, wherein luminance within the area drops to a value of less than about ½ of the luminance of an effective luminous area of the device. Generally, the non-luminous area of a unit fluorescent module is influenced by the width A of an upper surface of the upper lamp fixing assemblies 43a and 43b, such that the narrower the width A is, the smaller the non-luminous area. Accordingly, it is possible to decrease the width A by exposing the electrodes 33 and 33a outside the upper and lower lamp fixing assemblies 43a, 43b, 41a, and 41b, and by covering the exposed portion of the electrodes 33 and 33a with the insulating film 32. Further, it is possible to lengthen the electrodes 33 and 33a, thereby reducing the amount and the frequency of driving voltage applied thereto. With a reduced amount of driving voltage, less heat may be generated and the life of the fluorescent lamp may be extended.

[0042] In addition, the backlight device may further include a light scattering member (not shown), such as a diffusion sheet or a diffusion plate, arranged above the first and second upper lamp fixing assemblies 43a and 43b for uniformly distributing light emitted from the fluorescent lamps 31 onto a LCD panel (not shown). The backlight device may also include a reflection plate (not shown) arranged below the first and second lower lamp fixing assemblies 41a and 41b for directing light emitted from the fluorescent lamps 31 onto a center portion of the LCD panel. In addition, the height h of the upper and lower lamp fixing assemblies 43a, 43b, 41a, and 41b may be defined by a length from an upper surface of the reflection plate to a lower surface of the light scattering member.

[0043] FIG. 5A is a perspective view of another exemplary direct-type backlight device according to the present invention, and FIG. 5B is a cross-sectional view of the exemplary backlight device illustrated in FIG. 5A. In FIG. 5A, a backlight device may include a plurality of fluorescent lamps 31a arranged parallel to each other, first and second lower lamp fixing assemblies 51a and 51b arranged facing each other, first and second upper lamp fixing assemblies 53a and 53b arranged facing each other, and power-incoming lines 36 and 36a. The fluorescent lamps 31a may be CCFL lamps and may have internal electrodes 34 and 34a at both ends thereof. In addition, the fluorescent lamps 31a may have a plurality of lamp holders 35 and 35a formed at both ends of the fluorescent lamps 31a for holding the internal electrodes 34 and 34a and the power incoming lines 36 and 36a. Furthermore, the power-incoming lines 36 and 36a may connect the electrodes 34 and 34a to a driving circuit (not shown) via a single connector (not shown) for driving and supplying a power to the fluorescent lamps 31a. Accordingly, the number of connectors used within the backlight device may be reduced and the interconnection between the fluorescent lamps and the driving circuit may be simplified.

[0044] In addition, the first and second lower lamp fixing assemblies 51a and 51b may face each other at a predetermined interval to correspond to a length of the fluorescent lamps 31a, and may have a plurality of grooves 55 formed along the sides thereof. Further, the first and second upper lamp fixing assemblies 53a and 53b may be arranged at the same predetermined interval as the first and second lower lamp fixing assemblies 51a and 51b, and may have a plurality of grooves 55a formed along the sides thereof to correspond the grooves 55. The grooves 55 and 55a may be formed such that the fluorescent lamps 31a completely penetrate the first and second upper and lower lamp fixing assemblies 53a, 53b, 51a, and 51b. Also, the lamp holders 35 and 35a may have the same diameter, such that the grooves 55 may accommodate about half of the diameter of the lamp holders 35 and 35a, and the grooves 55a may accommodate the remaining half of the diameter of the lamp holders 35 and 35a. Accordingly, the ends of the fluorescent lamps 31a may be securely fixed within the grooves 55 and 55a of the lower and upper lamp fixing assemblies 51a, 51b, 53a, and 53b, thereby making the installment/replacement of the fluorescent lamps 31 a easier.

[0045] As shown in FIG. 5B, the first and second upper lamp fixing assemblies 53a and 53b may have a tapering width, wherein the width of the surfaces contacting the lower lamp fixing assemblies 51a and 51b may be larger than the width A of the opposing surfaces. For example, the first and second lamp fixing assemblies 53a and 53b may have an inclined angle θ of about 10° to about 30°. Also, the electrodes 34 and 34a may be partially exposed within an effective luminous area, and the partially exposed portions may have a length X. The length X may depend on the incline angle θ and a height h of the first upper and lower lamp fixing assemblies 53a and 51a or of the second upper and lower lamp fixing assemblies 53b and 51b. For example, the exposed length X of the electrodes 34 and 34a may be within about 35% of the height h of the first and second upper and lower lamp fixing assemblies 53a, 53b, 51a, and 51b, i.e., X≦0.35 h. If the incline angle θ is set at a range of about 20-24°, the length X may correspond to about 20% of the height h, i.e., X=0.2h. Accordingly, the width A of the first and second upper lamp fixing assemblies 53a and 53b may be reduced and the luminance at both ends of the fluorescent lamps 31a may be enhanced without diminishing quality of image within the effective luminous area.

[0046] The backlight device may further include a non-luminous area, wherein luminance within the area drops to a value of less than about ½ of the luminance of an effective luminous area of the device. Generally, the non-luminous area of a unit fluorescent module is influenced by the width A of an upper surface of the upper lamp fixing assemblies 53a and 53b, such that the narrower the width A is, the smaller the non-luminous area. Accordingly, it is possible to decrease the width A by exposing the electrodes 34 and 34a outside the upper and lower lamp fixing assemblies 53a, 53b, 51a, and 51b. Further, it is possible to lengthen the electrodes 34 and 34a, thereby reducing the amount and the frequency of driving voltage applied thereto. With a reduced amount of driving voltage, less heat may be generated and the life of the fluorescent lamp may be extended.

[0047] In addition, the backlight device may further include a light scattering member (not shown), such as a diffusion sheet or a diffusion plate, arranged above the first and second upper lamp fixing assemblies 53a and 53b for uniformly distributing light emitted from the fluorescent lamps 31a onto a LCD panel (not shown). The backlight device may also include a reflection plate (not shown) arranged below the first and second lower lamp fixing assemblies 51a and 51b for directing light emitted from the fluorescent lamps 31a onto a center portion of the LCD panel. In addition, the height h of the upper and lower lamp fixing assemblies 53a, 53b, 51a, and 51b may be defined by a length from an upper surface of the reflection plate to a lower surface of the light scattering means.

[0048] FIGS. 6A and 6B are perspective views of another exemplary direct-type backlight device according to the present invention, and FIG. 6C is a cross-sectional view of the exemplary backlight device illustrated in FIG. 6B. In FIG. 6A, a backlight device may include a plurality of fluorescent lamps 31 arranged parallel to each other, first and second lower lamp fixing assemblies 61a and 61b arranged facing each other, first and second upper lamp fixing assemblies 63a and 63b arranged facing each other, and conductive layers 67a, 67b, 67c, and 67d formed along the sides of the lamp fixing assemblies 61a, 61b, 63a, and 63b. The fluorescent lamps 31 may be EEFL lamps and may have external electrodes 33 and 33a, and insulating layers 32 at both ends thereof. Alternatively, the fluorescent lamps 31 may be replaced by the CCFL lamps 31a, shown in FIG. 3B, such that only the power-incoming lines 9 and 9a may be extended outside of the lamp fixing assemblies 61a, 61b, 63a, and 63b.

[0049] In addition, the first and second lower lamp fixing assemblies 61a and 61b may face each other at a predetermined interval to correspond to a length of the fluorescent lamps 31, and may have a plurality of grooves 65 formed along the sides thereof. Further, the first and second upper lamp fixing assemblies 63a and 63b may be arranged at the same predetermined interval as the first and second lower lamp fixing assemblies 61a and 61b, and may have a plurality of grooves 65a formed along the sides thereof to correspond the grooves 65. The grooves 65 and 65a may be formed such that the fluorescent lamps 31 only partially penetrate the first and second upper and lower lamp fixing assemblies 63a, 63b, 61a, and 61b. Also, the grooves 65 may accommodate about half of the diameter of the fluorescent lamps 31 and the grooves 65a may accommodate the remaining half of the diameter of the fluorescent lamp 31. Accordingly, the ends of the fluorescent lamps 31 may be securely fixed within the grooves 65 and 65a of the lower and upper lamp fixing assemblies 61a, 61b, 63a, and 63b, as shown in FIG. 6B, thereby making the installment/replacement of the fluorescent lamps 31 easier and reducing external impact on the fluorescent lamps 31.

[0050] As shown in FIG. 6C, the first and second upper lamp fixing assemblies 63a and 63b may have a tapering width, wherein the width of the surfaces contacting the lower lamp fixing assemblies 61a and 61b may be larger than a width A of the opposing surfaces. For example, the first and second lamp fixing assemblies 63a and 63b may have an inclined angle θ of about 10° to about 30°. Also, the external electrodes 63 and 63a may be partially exposed within an effective luminous area, and the partially exposed portions may have a length of X. The length X may depend on the incline angle θ and a height h of the first upper and lower lamp fixing assemblies 63a and 61a or of the second upper and lower lamp fixing assemblies 63b and 61b. For example, the exposed length X of the electrodes 33 and 33a may be within about 35% of the height h of the first and second upper and lower lamp fixing assemblies 63a, 63b, 61a, and 61b, i.e., X≦0.35 h. If the incline angle θ is set at a range of about 20-24°, the length X may correspond to about 20% of the height h, i.e., X=0.2 h. Accordingly, the width A of the first and second upper lamp fixing assemblies 63a and 63b may be reduced and the luminance at both ends of the fluorescent lamps 31 may be enhanced without diminishing quality of image within the effective luminous area.

[0051] The backlight device may further include a non-luminous area, wherein luminance within the area drops to a value of less than about ½ of the luminance of an effective luminance area of the device. Generally, the non-luminous area of a unit fluorescent module is influenced by the width A of an upper surface of the upper lamp fixing assemblies 63a and 63b, such that the narrower the width A is, the smaller the non-luminous area. Accordingly, it is possible to decrease the width A by exposing the electrodes 33 and 33a outside the upper and lower lamp fixing assemblies 63a, 63b, 61a, and 61b, and by covering the exposed portion of the electrodes 33 and 33a with the insulating film 32. Further, it is possible to lengthen the electrodes 33 and 33a, thereby reducing the amount and the frequency of driving voltage applied thereto. With a reduced amount of driving voltage, less heat may be generated and the life of the fluorescent lamp may be extended.

[0052] FIG. 7A is a perspective view of another exemplary direct-type backlight device according to the present invention, and FIG. 7B is a cross-sectional view of the exemplary backlight device illustrated in FIG. 7A. In FIG. 7A, a backlight device may include a plurality of fluorescent lamps 31 arranged parallel to each other, first and second lower lamp fixing assemblies 71a and 71b arranged facing each other, a lower supporting system 91a, 91b, and 91c formed between the lower lamp fixing assemblies 71a and 71b for supporting the lower assemblies 71a and 71b, first and second upper lamp fixing assemblies 73a and 73b arranged facing each other, and conductive layers 77a, 77b, 77c, and 77d formed along the sides of the lamp fixing assemblies 71a, 71b, 73a, and 73b. The fluorescent lamps 31 may be EEFL lamps and may have external electrodes 33 and 33a, and insulating layers 32 at both ends thereof. Alternatively, the fluorescent lamps 31 may be replaced by the CCFL lamps 31a, shown in FIG. 3B, such that only the power-incoming lines 9 and 9a may be extended outside of the lamp fixing assemblies 71a, 71b, 73a, and 73b.

[0053] The first and second lower lamp fixing assemblies 71a and 71b may also have a plurality of grooves 75 formed along the sides thereof. Further, the first and second upper lamp fixing assemblies 73a and 73b may have a plurality of grooves 75a formed along the sides thereof to correspond the grooves 75. The grooves 75 and 75a may be formed such that the fluorescent lamps 31 completely or partially penetrate the first and second upper and lower lamp fixing assemblies 73a, 73b, 71a, and 71b. Also, the grooves 75 may accommodate about half of the diameter of the fluorescent lamps 31 and the grooves 75a may accommodate the remaining half of the diameter of the fluorescent lamp 31. Accordingly, the ends of the fluorescent lamps 31 may be securely fixed within the grooves 75 and 75a of the lower and upper lamp fixing assemblies 71a, 71b, 73a, and 73b, as shown in FIG. 7B, thereby making the installment/replacement of the fluorescent lamps 31 easier.

[0054] In addition, the first and second lower lamp fixing assemblies 71 a and 71b may face each other at a predetermined interval to correspond to a length of the fluorescent lamps 31, and the lower supporting system 91a, 91b, and 91c. Furthermore, the first and second lower lamp fixing assemblies 71a and 71b may be integrally formed with the lower supporting system 91a, 91b, and 91c. Accordingly, the first and second lower lamp fixing assemblies 71a and 71b may be accurately arranged to securely affix the fluorescent lamps 31. Inner surfaces of the first and second lower assemblies 71a and 71b and the lower supporting systems 91a, 91b, and 91c may be formed of material having good light reflection ability, such as synthetic resin, to perform as a reflection plate. Alternatively, a reflective material may be coated onto the inner surfaces of the first and second lower assemblies 71a and 71b and the lower supporting systems 91a, 91b, and 91c. Accordingly, a reflection plate may be formed, thereby irradiating light emitted from the fluorescent lamps 31 toward a LCD panel (not shown).

[0055] Furthermore, the first and second upper lamp fixing assemblies 73a and 73b may have a tapering width, wherein the width of the surfaces contacting the lower lamp fixing assemblies 71a and 71b may be larger than a width A of the opposing surfaces. For example, the first and second lamp fixing assemblies 73a and 73b may have an inclined angle θ of about 10° to about 30°. Also, the external electrodes 33 and 33a may be partially exposed within an effective luminous area, and the partially exposed portions may have a length of X.

[0056] FIG. 8A is a perspective view of another exemplary direct-type backlight device according to the present invention, and FIG. 8B is a cross-sectional view of the exemplary backlight device illustrated in FIG. 8A. In FIG. 8A, a backlight device may include a plurality of fluorescent lamps 31 arranged parallel to each other, first and second lower lamp fixing assemblies 81a and 81b arranged facing each other, a lower supporting system 191a< /italic>, 191b< /italic>, and 191c formed between the lower lamp fixing assemblies 81a and 81b for supporting the lower assemblies 81a and 81b, first and second upper lamp fixing assemblies 83a and 83b arranged facing each other, an upper supporting system 100a and 100b formed between the upper lamp fixing assemblies 83a and 83b, and conductive layers 87a, 87b, 87c, and 87d formed along the sides of the lamp fixing assemblies 81a, 81b, 83a, and 83b. The fluorescent lamps 31 may be EEFL lamps and may have external electrodes 33 and 33a, and insulating layers 32 at both ends thereof. Alternatively, the fluorescent lamps 31 may be replaced by the CCFL lamps 31a, shown in FIG. 3B, such that only the power-incoming lines 9 and 9a may be extended outside of the lamp fixing assemblies 81a, 81b, 83a, and 83b.

[0057] The first and second lower lamp fixing assemblies 81a and 81b may also have a plurality of grooves 85 formed along the sides thereof. Further, the first and second upper lamp fixing assemblies 83a and 83b may have a plurality of grooves 85a formed along the sides thereof to correspond the grooves 85. The grooves 85 and 85a may be formed such that the fluorescent lamps 31 completely or partially penetrate the first and second upper and lower lamp fixing assemblies 83a, 83b, 81a, and 81b. Also, the grooves 85 may accommodate about half of the diameter of the fluorescent lamps 31 and the grooves 85a may accommodate the remaining half of the diameter of the fluorescent lamp 31. Accordingly, the ends of the fluorescent lamps 31 may be securely fixed within the grooves 85 and 85a of the lower and upper lamp fixing assemblies 81a, 81b, 83a, and 83b, as shown in FIG. 8B, thereby making the installment/replacement of the fluorescent lamps 31 easier.

[0058] In addition, the first and second lower lamp fixing assemblies 81a and 81b may face each other at a predetermined interval to correspond to a length of the fluorescent lamps 31, and the lower supporting system 191a< /italic>, 191b< /italic>, and 191c< /italic>. Furthermore, the first and second lower lamp fixing assemblies 81a and 81b may be integrally formed with the lower supporting system 191a< /italic>, 191b< /italic>, and 191c< /italic>. Accordingly, the first and second lower lamp fixing assemblies 81a and 81b may be accurately arranged to securely affix the fluorescent lamps 31. The first and second upper lamp fixing assemblies 83a and 83b may face each other at the same predetermined interval as the first and second lower lamp fixing assemblies 81a and 81b. Further, the first and second upper lamp fixing assemblies 83a and 83b may be integrally formed with the upper supporting system 100a and 100b< /italic>. Accordingly, the first and second lower lamp fixing assemblies 83a and 83b may be accurately arranged to securely affix the fluorescent lamps 31.

[0059] Furthermore, the first and second upper lamp fixing assemblies 83a and 83b may have a tapering width, wherein the width of the surfaces contacting the lower lamp fixing assemblies 81a and 81b is larger than a width A of the opposing surfaces. For example, the first and second lamp fixing assemblies 83a and 83b may have an inclined angle θ of about 10° to about 30°. Also, the external electrodes 33 and 33a may be partially exposed within an effective luminous area, and the partially exposed portions may have a length of X.

[0060] The aforementioned backlight devices may be used as light sources at a rear side or a front side of a display, or as a light emitting device by themselves. The aforementioned backlight device of the present invention has the following effects. First, lamp electrodes may expose in an effective luminous area of the backlight device, thereby decreasing a width of the upper lamp fixing assemblies and enhancing efficiency of the device. Second, lamp electrodes may be lengthened, thereby lowering the driving voltage and extending the life of the fluorescent lamps. Third, the upper lamp fixing assemblies may have a tapering width, thereby widening the effective luminous area. Fourth, supporting systems for supporting the upper and lower lamp fixing assemblies may be formed, thereby accurately arranging the lamp fixing assemblies and securely affixing the fluorescent lamps.

[0061] It will be apparent to those skilled in the art that various modifications and variations can be made in the backlight device and the method of fabricating the same of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.