Light guide panel usable with backlight unit, backlight unit employing the same, and manufacturing method thereof

A light guide panel usable with a backlight unit to convert a line light source into a surface light source, comprising:

• a transparent plate one side of which includes a plane of incidence to receive the line litht source;
• and
• a plurality of planes inclined with respect to the plane of incidence dividing an interior portion of the transparent plate, each of the respective inclined planes being partial-reflection-coated
• wherein the partial reflection coating of the inclined plane farthest from the line light source has 100% reflectivity.

A method of manufacturing a light guide panel usable with a backlight unit, the method comprising:

• partial-reflection-coating a plurality of transparent plates;
• making a transparent plate assembly by stacking and coupling the partial-reflection-coated transparent plates;
• and
• inclinedly cutting the transparent plate assembly to provide a plurality of light guide panels having a predetermined thickness,
• wherein the partial-reflection-coating of the plurality of transparent plates comprises partial-reflection-coating the plurality of transparent plates according to different coating specifications with respect to each other to make the transparent plates have increasing reflectivity, and the making of the transparent plate assembly comprises stacking and coupling the transparent plates in an order of the reflectivity of the partial reflection coating.

A method of converting a line light source into a surface light source, the method comprising:

• receiving light through a first surface;
• and
• sequentially passing the received light through a plurality of inclined planes to reflect a predetermined amount of the received light through a second surface orthogonal to the first surface,
• wherein the sequentially passing of the received light through the plurality of inclined planes comprises:
• sequentially receiving a decreasing amount of light at each inclined plane, and
• sequentially reflecting an increasing percentage of the decreasing amount of light toward the second surface at each inclined plane.

A backlight unit comprising:

• a line light source to irradiate light;
• and
• a light guide panel to convert the line light source into a surface light source and comprising a transparent plate including a first side which is a plane of incidence, and a plurality of planes inclined with respect to the plane of incidence dividing an interior portion of the transparent plate, each of the respective inclined planes being partial-reflection-coated to reflect through a second side a predetermined equal percentage amount of the light received from the line light source,
• wherein the respective inclined planes are partial-reflection-coated according to different coating specifications with respect to each other to make reflectivity increase in proportion to distance from the line light source.