Light guide plate with stepped edge and display device having the same

Abstract

A light guide plate includes a first surface having a light incident surface and a light reflect surface, a second surface facing the first surface, through which the reflected light exits, a first edge surface connected between edges of the light reflect surface and the second surface, and a second edge surface connected between edges of the light incident surface and the second surface, being opposite to the first edge surface. A light source is disposed on the light incident surface. A light guide plate may also include a stepped edge portion formed at a marginal area of the light guide plate on which a light source is combined. The stepped edge portion includes a light incident surface, a light reflect surface, an upper surface through which the reflected light exits the light guide plate, and a first edge surface connected between edges of the light reflect surface and the upper surface, being opposite to the stepped edge portion. A backlight assembly includes the light guide plate, a lamp unit including lamps and a lamp reflector that are disposed on the light incident surface, and a mold frame for receiving the stepped edge portion and the lamp unit.

1 . A light guide plate for adjusting paths of light provided from a light source, comprising: 
 a first surface having: 
 a light incident surface on which the light source is disposed and the light is incident; and  
 a light reflect surface for reflecting the light provided through the light incident surface;  
   a second surface facing the first surface, the light reflected by the light reflect surface exiting the second surface;    a first edge surface connected between edges of the light reflect surface and the second surface; and    a second edge surface connected between edges of the light incident surface and the second surface, the second edge surface being opposite to the first edge surface.    
   
   
       2 . The light guide plate of  claim 1 , wherein the second edge surface is slant toward the first surface such that an acute angle is formed between the second edge surface and the light incident surface.  
   
   
       3 . The light guide plate of  claim 1 , wherein the second edge surface includes: 
 a straight surface extend from the edge of the light incident surface in a direction substantially perpendicular to the light incident surface; and    an inclined surface extended from the edge of the second surface to be connected to a longitudinal edge of the straight surface, the longitudinal edge connected to the straight surface being opposite to a longitudinal edge connected to the second surface in the inclined surface, the inclined surface being slant toward the first surface such that the a slope connecting the longitudinal edges of the inclined surface has an acute angle with respect to the first surface and an obtuse angle with respect to the second surface.    
   
   
       4 . The light guide plate of  claim 1 , further including a protrusion formed on the light incident surface, wherein the light source is disposed on the surface of the protrusion.  
   
   
       5 . The light guide plate of  claim 4 , wherein the light source includes a cover for receiving lamps and being combined on the light incident surface, the protrusion being combined within opposing sides of the cover.  
   
   
       6 . The light guide plate of  claim 5 , wherein the first surface includes two shoulders each formed at a longitudinal edge between the protrusion and the first surface, the opposing sides of the cover being combined on the two shoulders, respectively.  
   
   
       7 . The light guide plate of  claim 6 , wherein the protrusion has a width substantially identical to a length between the opposing sides of the cover.  
   
   
       8 . The light guide plate of  claim 1 , wherein the second surface includes a light emission surface through which the light exists, and a second light incident surface extended from a longitudinal edge of the second edge surface to the light emission surface, the second light incident surface being opposite to the light incident surface of the first surface.  
   
   
       9 . The light guide plate of  claim 8 , wherein the light incident surface of the first surface includes a first groove and the second light incident surface includes a second groove, the first and second grooves each receiving at least one lamp of the light source.  
   
   
       10 . The light guide plate of  claim 9 , wherein a cover is disposed on the light incident surface of the first surface, the second light incident surface, and the second edge surface to receive the lamps in the first and second grooves.  
   
   
       11 . A backlight assembly for providing light, comprising: 
 a light guide plate including: 
 a first surface having: 
 a light incident surface on which the light source is disposed and the light is incident; and  
 a light reflect surface for reflecting the light provided through the light incident surface;  
 
 a second surface facing the first surface, the light reflected by the light reflect surface exiting the second surface;  
 a first edge surface connected between edges of the light reflect surface and the second surface; and  
 a second edge surface connected between edges of the light incident surface and the second surface, the second edge surface being opposite to the first edge surface;  
   a lamp unit disposed on the light incident surface, the lamp unit including: 
 at least one lamp for generating the light; and  
 a lamp reflector for reflecting the light from the at least one lamp; and  
   a mold frame including: 
 a channel space for receiving the lamp unit; and  
 a groove for receiving an electrical line electrically connected to the lamp unit.  
   
   
   
       12 . The backlight assembly of  claim 11 , wherein the second edge surface is slant toward the first surface such that an acute angle is formed between the second edge surface and the light incident surface.  
   
   
       13 . The backlight assembly of  claim 11 , wherein the second edge surface includes: 
 a straight surface extend from the edge of the light incident surface in a direction substantially perpendicular to the light incident surface; and    an inclined surface extended from the edge of the second surface to be connected to a longitudinal edge of the straight surface, the longitudinal edge connected to the straight surface being opposite to a longitudinal edge connected to the second surface in the inclined surface, the inclined surface being slant toward the first surface such that the a slope connecting the longitudinal edges of the inclined surface has an acute angle with respect to the first surface and an obtuse angle with respect to the second surface.    
   
   
       14 . The backlight assembly of  claim 11 , wherein the light guide plate further includes a protrusion formed on the light incident surface, and the light source is disposed on the surface of the protrusion.  
   
   
       15 . The backlight assembly of  claim 14 , wherein the light source includes a cover for receiving lamps and being combined on the light incident surface, the protrusion being combined within opposing sides of the cover, the protrusion having a width substantially identical to a length between the opposing sides of the cover.  
   
   
       16 . The backlight assembly of  claim 11 , wherein the second surface includes a light emission surface through which the light exists and a second light incident surface extended from a longitudinal edge of the second edge surface to the light emission surface, the second light incident surface being opposite to the light incident surface of the first surface, and the light incident surface of the first surface includes a first groove and the second light incident surface includes a second groove, the first and second grooves each receiving at least one lamp of the light source.  
   
   
       17 . The backlight assembly of  claim 11 , wherein the mold frame has a bottom, a first wall extended from a longitudinal edge of the bottom along the second edge surface of the light guide plate, and a second wall opposing to the first wall and extended from the other longitudinal edge of the bottom toward the light reflect surface of the light guide plate, wherein the groove for receiving the electrical line is formed at the second wall of the mold frame.  
   
   
       18 . A liquid crystal display device comprising: 
 a display unit for displaying images by processing image data externally provided; and    a backlight assembly for providing light to the display unit, the back light assembly including: 
 a light guide plate including: 
 a first surface having: 
 a light incident surface on which the light source is disposed and the light is incident; and  
 a light reflect surface for reflecting the light provided through the light incident surface;  
 
 a second surface facing the first surface, the light reflected by the light reflect surface exiting the second surface;  
 a first edge surface connected between edges of the light reflect surface and the second surface; and  
 a second edge surface connected between edges of the light incident surface and the second surface, the second edge surface being opposite to the first edge surface;  
 
 a lamp unit disposed on the light incident surface, the lamp unit including: 
 at least one lamp for generating the light; and  
 a lamp reflector for reflecting the light from the at least one lamp; and  
 
 a mold frame including: 
 a channel space for receiving the lamp unit; and  
 a groove for receiving an electrical line electrically connected to the lamp unit.  
 
   
   
   
       19 . The liquid crystal display device of  claim 18 , wherein the light guide plate has a wedge shape such that a thickness at an area proximate the light incident surface is larger than a thickness at an area proximate the first edge surface, the light incident surface is substantially parallel with the second surface, the first and second edge surfaces being substantially parallel with each other, and the second edge surface is slant toward the first surface such that an acute angle is formed between the second edge surface and the light incident surface.  
   
   
       20 . The liquid crystal display device of  claim 19 , wherein the second edge surface includes: 
 a straight surface extend from the edge of the light incident surface in a direction substantially perpendicular to the light incident surface; and    an inclined surface extended from the edge of the second surface to be connected to a longitudinal edge of the straight surface, the longitudinal edge connected to the straight surface being opposite to a longitudinal edge connected to the second surface in the inclined surface, the inclined surface being slant toward the first surface such that the a slope connecting the longitudinal edges of the inclined surface has an acute angle with respect to the first surface and an obtuse angle with respect to the second surface.    
   
   
       21 . The liquid crystal display device of  claim 19 , wherein the light guide plate further includes a protrusion formed on the light incident surface, and the light source is disposed on the surface of the protrusion and includes a cover for receiving lamps and being combined on the light incident surface, the protrusion being combined within opposing sides of the cover and having a width substantially identical to a length between the opposing sides of the cover.  
   
   
       22 . The liquid crystal display device of  claim 19 , wherein the second surface includes a light emission surface through which the light exists and a second light incident surface extended from a longitudinal edge of the second edge surface to the light emission surface, the second light incident surface being opposite to the light incident surface of the first surface, and the light incident surface of the first surface includes a first groove and the second light incident surface includes a second groove, the first and second grooves each receiving at least one lamp of the light source.  
   
   
       23 . A light guide plate for adjusting paths of light provided from a light source, comprising: 
 a stepped edge portion formed at a marginal area of the light guide plate on which the light source is combined, the stepped edge portion including a light incident surface on which the light from the light source is incident;    a light reflect surface for reflecting the light provided through the light incident surface;    an upper surface facing the light reflect surface, the light reflected by the light reflect surface exiting the upper surface; and    a first edge surface connected between edges of the light reflect surface and the upper surface, the first edge surface being opposite to the stepped edge portion.    
   
   
       24 . The light guide plate of  claim 23 , wherein the light guide plate has a wedge shape such that a thickness at an area proximate the stepped edge portion is larger than a thickness at an area proximate the first edge surface.  
   
   
       25 . The light guide plate of  claim 23 , wherein the light source includes a cover for receiving at least one lamp, the cover being combined on the stepped edge portion such that one of opposing sides of the cover is in contact with one of the longitudinal edges of the light incident surface and the other of the opposing sides of the cover is in contact with the other of the longitudinal edges of the light incident surface.  
   
   
       26 . The light guide plate of  claim 25 , wherein the cover includes a bottom formed between the opposing sides, an electrical line electrically connected with the light source being disposed under the bottom of the cover.  
   
   
       27 . The light guide plate of  claim 23 , wherein the light incident surface includes a first inclined surface extended from an edge of the light reflect surface toward the upper surface, the first inclined surface being slant such that a slope line connecting longitudinal edges of the first inclined surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       28 . The light guide plate of  claim 27 , wherein the light source has at least one lamp disposed on the first inclined surface, and a cover receiving the at least one lamp is combined on the first inclined surface.  
   
   
       29 . The light guide plate of  claim 28 , wherein the light incident surface further including a second edge surface extended from one of the longitudinal edges of the first inclined surface to the upper surface, the other of the longitudinal edges of the first inclined surface being in contact with the light reflect surface, the second edge surface being substantially parallel with the first edge surface.  
   
   
       30 . The light guide plate of  claim 27 , wherein the first inclined surface is a flat surface on which lamps of the light source are arranged parallel with each other in their longitudinal direction, and the flat surface is slant such that the slope line connecting the longitudinal edges of the first inclined surface is substantially parallel with a line connecting longitudinal axes of the lamps disposed on the flat surface.  
   
   
       31 . The light guide plate of  claim 27 , wherein the light incident surface further includes a second inclined surface extended from an edge of the upper surface toward the first inclined surface so that the first and second inclined surfaces form a convex edge, at least one lamp of the light source being disposed on the second inclined surface.  
   
   
       32 . The light guide plate of  claim 31 , wherein a cover for receiving the at least one lamp is combined on the light incident surface such that one of opposing sides of the cover is in contact with a longitudinal edge of the first inclined surface proximate the light reflect surface and the other of the opposing sides of the cover is in contact with a longitudinal edge of the second inclined surface proximate the upper surface.  
   
   
       33 . The light guide plate of  claim 32 , wherein the second inclined surface is a flat surface slanting such that a slope line connecting longitudinal edges of the second inclined surface forms an acute angle with respect to the light reflect surface and an obtuse angle with respect to the upper surface.  
   
   
       34 . The light guide plate of  claim 31 , wherein the light incident surface further includes a second edge surface formed between the first and second inclined surfaces, the second edge surface being substantially parallel with the first edge surface.  
   
   
       35 . The light guide plate of  claim 31 , wherein the first and second inclined surfaces are each a concave arcuate surface.  
   
   
       36 . The light guide plate of  claim 23 , wherein the light incident surface includes: 
 a plane surface extended from an edge of the light reflect surface in a direction opposite to the first edge surface, the plane surface being substantially parallel with the upper surface; and    an inclined surface extended from a longitudinal edge of the plane surface toward the upper surface, the inclined surface being slant such that a slope line connecting longitudinal edges of the inclined surface forms an obtuse angle with respect to the plane surface and an acute angle with respect to the upper surface.    
   
   
       37 . The light guide plate of  claim 36 , wherein the light source has at least two lamps at least one of which is disposed on each of the plane surface and the inclined surface.  
   
   
       38 . The light guide plate of  claim 37 , wherein a cover receiving the at least two lamps is combined on the stepped edge portion such that one of opposing sides of the cover is in contact with the other longitudinal edge of the plane surface proximate the light reflect surface and the other of the opposing sides of the cover is in contact with the longitudinal edge of the inclined surface proximate the upper surface.  
   
   
       39 . The light guide plate of  claim 38 , wherein the light incident surface further includes a second edge surface connected between the upper surface and the inclined surface, the second edge surface being substantially parallel with the first edge surface.  
   
   
       40 . The light guide plate of  claim 23 , wherein the stepped edge portion includes a first step portion forming a first shoulder for receiving at least one lamp of the light source, the first step portion being formed concavely inward the light guide plate.  
   
   
       41 . The light guide plate of  claim 40 , wherein the first shoulder of the first step portion is rounded.  
   
   
       42 . The light guide plate of  claim 40 , wherein the first step portion includes the light incident surface for receiving the light from the at least one lamp, the light incident surface being slant such that a slope line connecting longitudinal edges of the light incident surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       43 . The light guide plate of  claim 40 , wherein the light guide plate further includes a second edge surface connected between the upper surface and the first step portion, the second edge surface being substantially parallel with the first edge surface.  
   
   
       44 . The light guide plate of  claim 40 , wherein the stepped edge portion further includes a second step portion forming a second shoulder for receiving at least one lamp of the light source, the second step portion being formed concavely inward the light guide plate and the first and second step portions being adjacent to each other.  
   
   
       45 . The light guide plate of  claim 44 , wherein the first and second step portions has a slope such that a line connecting longitudinal axes of the lamps received in the first and second shoulders forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       46 . The light guide plate of  claim 45 , wherein the first and second step portions each have a rise substantially perpendicular to the upper surface and a run substantially parallel with the upper surface, the rise having a width smaller than a width of the run.  
   
   
       47 . The light guide plate of  claim 44 , wherein the second shoulder has a round shape.  
   
   
       48 . The light guide plate of  claim 45 , wherein the first and second step portions each have a rise substantially perpendicular to the upper surface and a run substantially parallel with the upper surface, the rise having a width larger than a width of the run.  
   
   
       49 . The light guide plate of  claim 48 , wherein the first step portion has a first depth that is a length from the first rise to the end of the light guide plate, and the second step portion has a second depth that is a length from the second rise to the end of the light guide plate, the first depth being larger than the second depth, and a difference between the first and second depths being smaller that a diameter the lamps.  
   
   
       50 . The light guide plate of  claim 44 , wherein the first and second step portions have a slope such that a line connecting longitudinal axes of the lamps received in the first and second shoulders forms an acute angle with respect to the light reflect surface and an obtuse angle with respect to the upper surface.  
   
   
       51 . The light guide plate of  claim 44 , wherein the first and second step portions are corrugated to each have a round valley for receiving the at least one lamp of the light source, a peak being formed between the round valleys of the first and second step portions.  
   
   
       52 . The light guide plate of  claim 51  wherein the first and second step portions have a slope such that a line connecting longitudinal axes of the lamps received in the round valleys forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       53 . The light guide plate of  claim 51 , wherein the first and second step portions have a slope substantially perpendicular to the upper surface.  
   
   
       54 . The light guide plate of  claim 23 , wherein the stepped edge portion includes a groove for receiving at least one lamp of the light source, the light incident surface includes an inner surface of the groove on which the light is incident.  
   
   
       55 . The light guide plate of  claim 54 , wherein the groove has one of a U-shape, a V-shape and a rectangular shape.  
   
   
       56 . A backlight assembly for providing light, comprising: 
 a light guide plate including: 
 a stepped edge portion formed at a marginal area of the light guide plate on which the light source is combined, the stepped edge portion including a light incident surface on which the light from the light source is incident;  
 a light reflect surface for reflecting the light provided through the light incident surface;  
 an upper surface facing the light reflect surface, the light reflected by the light reflect surface exiting the upper surface; and  
 a first edge surface connected between edges of the light reflect surface and the upper surface, the first edge surface being opposite to the stepped edge portion;  
   a lamp unit disposed on the stepped edge portion of the light guide plate, the lamp unit including: 
 at least one lamp for generating the light; and  
 a lamp reflector for receiving the at least one lamp and reflecting the light from the at least one lamp; and  
   a mold frame including: 
 a bottom disposed under the lamp unit and being substantially parallel with the upper surface; and  
 a side wall extended from a longitudinal edge of the bottom in a direction substantially perpendicular to the bottom, the bottom and the side wall receiving the stepped edge portion of the light guide plate and the lamp unit.  
   
   
   
       57 . The backlight assembly of  claim 56 , wherein the light source includes a cover for receiving at least one lamp, the cover being combined on the stepped edge portion such that one of opposing sides of the cover is in contact with one of the longitudinal edges of the light incident surface and the other of the opposing sides of the cover is in contact with the other of the longitudinal edges of the light incident surface, the cover including a bottom formed between the opposing sides, an electrical line electrically connected with the light source being disposed under the bottom of the cover.  
   
   
       58 . The backlight assembly of  claim 56 , wherein the light incident surface includes a first inclined surface extended from an edge of the light reflect surface toward the upper surface, the first inclined surface being slant such that a slope line connecting longitudinal edges of the first inclined surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       59 . The backlight assembly of  claim 58 , wherein the light source has at least one lamp disposed on the first inclined surface, a cover for receiving the at least one lamp being combined on the first inclined surface, and the light incident surface further includes a second edge surface extended from one of the longitudinal edges of the first inclined surface to the upper surface, the other of the longitudinal edges of the first inclined surface being in contact with the light reflect surface, the second edge surface being substantially parallel with the first edge surface.  
   
   
       60 . The backlight assembly of  claim 58 , wherein the first inclined surface is a flat surface on which lamps of the light source are arranged parallel with each other in their longitudinal direction, and the flat surface is slant such that the slope line connecting the longitudinal edges of the first inclined surface is substantially parallel with a line connecting longitudinal axes of the lamps disposed on the flat surface.  
   
   
       61 . The backlight assembly of  claim 58 , wherein the light incident surface further includes a second inclined surface extended from an edge of the upper surface toward the first inclined surface so that the first and second inclined surfaces form a convex edge, at least one lamp of the light source being disposed on the second inclined surface.  
   
   
       62 . The backlight assembly of  claim 61 , wherein a cover for receiving the at least one lamp is combined on the light incident surface such that one of opposing sides of the cover is in contact with a longitudinal edge of the first inclined surface proximate the light reflect surface and the other of the opposing sides of the cover is in contact with a longitudinal edge of the second inclined surface proximate the upper surface, and the second inclined surface is a flat surface slanting such that a slope line connecting longitudinal edges of the second inclined surface forms an acute angle with respect to the light reflect surface and an obtuse angle with respect to the upper surface.  
   
   
       63 . The backlight assembly of  claim 61 , wherein the first and second inclined surfaces are each a concave arcuate surface.  
   
   
       64 . The backlight assembly of  claim 56 , wherein the light incident surface includes: 
 a plane surface extended from an edge of the light reflect surface in a direction opposite to the first edge surface, the plane surface being substantially parallel with the upper surface; and    an inclined surface extended from a longitudinal edge of the plane surface toward the upper surface, the inclined surface being slant such that a slope line connecting longitudinal edges of the inclined surface forms an obtuse angle with respect to the plane surface and an acute angle with respect to the upper surface,    wherein the light source has at least two lamps at least one of which is disposed on each of the plane surface and the inclined surface.    
   
   
       65 . The backlight assembly of  claim 64 , wherein a cover receiving the at least two lamps is combined on the stepped edge portion such that one of opposing sides of the cover is in contact with the other longitudinal edge of the plane surface proximate the light reflect surface and the other of the opposing sides of the cover is in contact with the longitudinal edge of the inclined surface proximate the upper surface, and the light incident surface further includes a second edge surface connected between the upper surface and the inclined surface, the second edge surface being substantially parallel with the first edge surface.  
   
   
       66 . The backlight assembly of  claim 56 , wherein the stepped edge portion includes a first step portion forming a first shoulder for receiving at least one lamp of the light source, the first step portion being formed concavely inward the light guide plate.  
   
   
       67 . The backlight assembly of  claim 66 , wherein the first shoulder of the first step portion is rounded.  
   
   
       68 . The backlight assembly of  claim 66 , wherein the first step portion includes the light incident surface for receiving the light from the at least one lamp, the light incident surface being slant such that a slope line connecting longitudinal edges of the light incident surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       69 . The backlight assembly of  claim 66 , wherein the light guide plate further includes a second edge surface connected between the upper surface and the first step portion, the second edge surface being substantially parallel with the first edge surface.  
   
   
       70 . The backlight assembly of  claim 66 , wherein the stepped edge portion further includes a second step portion forming a second shoulder for receiving at least one lamp of the light source, the second step portion being formed concavely inward the light guide plate and the first and second step portions being adjacent to each other.  
   
   
       71 . The backlight assembly of  claim 70 , wherein the first and second step portions have a slope such that a line connecting longitudinal axes of the lamps received in the first and second shoulders forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       72 . The backlight assembly of  claim 71 , wherein the first and second step portions each have a rise substantially perpendicular to the upper surface and a run substantially parallel with the upper surface, the rise having a width smaller than a width of the run.  
   
   
       73 . The backlight assembly of  claim 71 , wherein the first and second step portions each have a rise substantially perpendicular to the upper surface and a run substantially parallel with the upper surface, the rise having a width larger than a width of the run, the first step portion has a first depth that is a length from the first rise to the end of the light guide plate, and the second step portion has a second depth that is a length from the second rise to the end of the light guide plate, the first depth being larger than the second depth, a difference between the first and second depths being smaller that a diameter the lamps.  
   
   
       74 . The backlight assembly of  claim 70 , wherein the first and second step portions are corrugated to each have a round valley for receiving the at least one lamp of the light source, a peak being formed between the round valleys of the first and second step portions, and the first and second step portions have a slope such that a line connecting longitudinal axes of the lamps received in the round valleys forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       75 . The backlight assembly of  claim 70 , wherein the first and second step portions are corrugated to each have a round valley for receiving the at least one lamp of the light source, a peak being formed between the round valleys of the first and second step portions, the first and second step portions having a slope substantially perpendicular to the upper surface.  
   
   
       76 . The backlight assembly of  claim 56 , wherein the stepped edge portion includes a groove for receiving at least one lamp of the light source, the light incident surface includes an inner surface of the groove on which the light is incident.  
   
   
       77 . The backlight assembly of  claim 56 , wherein the lamp reflector is slant with respect to the bottom and the side wall of the mold frame to form a space between the lamp reflector and the mold frame, an electrical line connected to the lamp unit being drawn out through the space.  
   
   
       78 . The backlight assembly of  claim 77 , wherein the space is enclosed with a bottom of the lamp reflector, the sidewall of the mold frame, and a middle chassis securing the light guide plate on the mold frame.  
   
   
       79 . The backlight assembly of  claim 56 , wherein the lamp reflector includes: 
 a first reflect portion for receiving a first lamp of the lamp unit and reflecting light from the first lamp;    a second reflect portion for receiving a second lamp of the lamp unit and reflecting light from the second lamp; and    a flat peak connected between the first and second reflect portions to form a channel space under the lamp reflector, an electrical line connected to the lamp unit being drawn out through the channel space.    
   
   
       80 . The backlight assembly of  claim 79 , wherein the lamp reflector is slant such that a slope line connecting longitudinal axes of the first and second lamps forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       81 . The backlight assembly of  claim 56 , wherein the lamp reflector includes: 
 a first reflect panel disposed on the stepped edge portion of the light guide plate such that the at least one lamp is securely received between the light incident surface of the light guide plate and the first reflect panel; and    a second reflect panel extended from a longitudinal edge of the first reflect panel under the light reflect surface of the light guide plate toward first edge surface of the light guide plate.    
   
   
       82 . The backlight assembly of  claim 81 , wherein the stepped edge portion of the light guide plate receives two or more lamps that are arranged such that a line connecting longitudinal axes of the lamps is substantially perpendicular to the upper surface, the first reflect panel being substantially parallel to the line connecting the axes of the lamps and the second reflect panel being substantially perpendicular to the first reflect panel.  
   
   
       83 . A liquid crystal display device comprising: 
 a display unit for displaying images by processing image data externally provided; and    a backlight assembly for providing light to the display unit, the backlight assembly including: 
 a light guide plate including: 
 a stepped edge portion formed at a marginal area of the light guide plate on which the light source is combined, the stepped edge portion including a light incident surface on which the light from the light source is incident;  
 a light reflect surface for reflecting the light provided through the light incident surface;  
 an upper surface facing the light reflect surface, the light reflected by the light reflect surface exiting the upper surface; and  
 a first edge surface connected between edges of the light reflect surface and the upper surface, the first edge surface being opposite to the stepped edge portion;  
 
 a lamp unit disposed on the stepped edge portion of the light guide plate, the lamp unit including: 
 at least one lamp for generating the light; and  
 a lamp reflector for receiving the at least one lamp and reflecting the light from the at least one lamp; and  
 
 a mold frame including: 
 a bottom disposed under the lamp unit and being substantially parallel with the upper surface; and  
 a side wall extended from a longitudinal edge of the bottom in a direction substantially perpendicular to the bottom, the bottom and the side wall receiving the stepped edge portion of the light guide plate and the lamp unit.  
 
   
   
   
       84 . The liquid crystal display device of  claim 83 , wherein the light source includes a cover for receiving at least one lamp, the cover being combined on the stepped edge portion such that one of opposing sides of the cover is in contact with one of the longitudinal edges of the light incident surface and the other of the opposing sides of the cover is in contact with the other of the longitudinal edges of the light incident surface, the cover including a bottom formed between the opposing sides, an electrical line electrically connected with the light source being disposed under the bottom of the cover.  
   
   
       85 . The liquid crystal display device of  claim 83 , wherein the light incident surface includes a first inclined surface extended from an edge of the light reflect surface toward the upper surface, the first inclined surface being slant such that a slope line connecting longitudinal edges of the first inclined surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface, and wherein the light source has at least one lamp disposed on the first inclined surface, a cover for receiving the at least one lamp being combined on the first inclined surface, and the light incident surface further includes a second edge surface extended from one of the longitudinal edges of the first inclined surface to the upper surface, the other of the longitudinal edges of the first inclined surface being in contact with the light reflect surface, the second edge surface being substantially parallel with the first edge surface.  
   
   
       86 . The liquid crystal display device of  claim 83 , wherein the light incident surface includes a first inclined surface extended from an edge of the light reflect surface toward the upper surface, the first inclined surface being slant such that a slope line connecting longitudinal edges of the first inclined surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface, and wherein the first inclined surface is a flat surface on which lamps of the light source are arranged parallel with each other in their longitudinal direction, and the flat surface is slant such that the slope line connecting the longitudinal edges of the first inclined surface is substantially parallel with a line connecting longitudinal axes of the lamps disposed on the flat surface.  
   
   
       87 . The liquid crystal display device of  claim 83 , wherein the light incident surface includes: 
 a first inclined surface extended from an edge of the light reflect surface toward the upper surface, the first inclined surface being slant such that a slope line connecting longitudinal edges of the first inclined surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface; and    a second inclined surface extended from an edge of the upper surface toward the first inclined surface so that the first and second inclined surfaces form a convex edge, at least one lamp of the light source being disposed on the second inclined surface,    wherein a cover for receiving the at least one lamp is combined on the light incident surface such that one of opposing sides of the cover is in contact with a longitudinal edge of the first inclined surface proximate the light reflect surface and the other of the opposing sides of the cover is in contact with a longitudinal edge of the second inclined surface proximate the upper surface, and the second inclined surface is a flat surface slanting such that a slope line connecting longitudinal edges of the second inclined surface forms an acute angle with respect to the light reflect surface and an obtuse angle with respect to the upper surface.    
   
   
       88 . The liquid crystal display device of  claim 83 , wherein the light incident surface includes: 
 a plane surface extended from an edge of the light reflect surface in a direction opposite to the first edge surface, the plane surface being substantially parallel with the upper surface; and    an inclined surface extended from a longitudinal edge of the plane surface toward the upper surface, the inclined surface being slant such that a slope line connecting longitudinal edges of the inclined surface forms an obtuse angle with respect to the plane surface and an acute angle with respect to the upper surface,    wherein the light source has at least two lamps at least one of which is disposed on each of the plane surface and the inclined surface.    
   
   
       89 . The liquid crystal display device of  claim 88 , wherein a cover receiving the at least two lamps is combined on the stepped edge portion such that one of opposing sides of the cover is in contact with the other longitudinal edge of the plane surface proximate the light reflect surface and the other of the opposing sides of the cover is in contact with the longitudinal edge of the inclined surface proximate the upper surface, and the light incident surface further includes a second edge surface connected between the upper surface and the inclined surface, the second edge surface being substantially parallel with the first edge surface.  
   
   
       90 . The liquid crystal display device of  claim 83 , wherein the stepped edge portion includes a first step portion forming a first shoulder for receiving at least one lamp of the light source, the first step portion being formed concavely inward the light guide plate, the first shoulder of the first step portion being rounded.  
   
   
       91 . The liquid crystal display device of  claim 83 , wherein the stepped edge portion includes a first step portion forming a first shoulder for receiving at least one lamp of the light source, and the first step portion is formed concavely inward the light guide plate and includes the light incident surface for receiving the light from the at least one lamp, the light incident surface being slant such that a slope line connecting longitudinal edges of the light incident surface forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       92 . The liquid crystal display device of  claim 83 , wherein the stepped edge portion includes a first step portion forming a first shoulder for receiving at least one lamp of the light source, the first step portion being formed concavely inward the light guide plate, and the light guide plate further includes a second edge surface connected between the upper surface and the first step portion, the second edge surface being substantially parallel with the first edge surface.  
   
   
       93 . The liquid crystal display device of  claim 83 , wherein the stepped edge portion includes: 
 a first step portion forming a first shoulder for receiving at least one lamp of the light source, the first step portion being formed concavely inward the light guide plate; and    a second step portion forming a second shoulder for receiving at least one lamp of the light source, the second step portion being formed concavely inward the light guide plate and the first and second step portions being adjacent to each other.    
   
   
       94 . The liquid crystal display device of  claim 93 , wherein the first and second step portions have a slope such that a line connecting longitudinal axes of the lamps received in the first and second shoulders forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface, and the first and second step portions each have a rise substantially perpendicular to the upper surface and a run substantially parallel with the upper surface, the rise having a width smaller than a width of the run.  
   
   
       95 . The liquid crystal display device of  claim 93 , wherein the first and second step portions have a slope such that a line connecting longitudinal axes of the lamps received in the first and second shoulders forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface, the first and second step portions each have a rise substantially perpendicular to the upper surface and a run substantially parallel with the upper surface, the rise having a width larger than a width of the run, the first step portion has a first depth that is a length from the first rise to the end of the light guide plate, and the second step portion has a second depth that is a length from the second rise to the end of the light guide plate, the first depth being larger than the second depth, a difference between the first and second depths being smaller that a diameter the lamps.  
   
   
       96 . The liquid crystal display device of  claim 93 , wherein the first and second step portions are corrugated to each have a round valley for receiving the at least one lamp of the light source, a peak being formed between the round valleys of the first and second step portions, and the first and second step portions have a slope such that a line connecting longitudinal axes of the lamps received in the round valleys forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.  
   
   
       97 . The liquid crystal display device of  claim 93 , wherein the first and second step portions are corrugated to each have a round valley for receiving the at least one lamp of the light source, a peak being formed between the round valleys of the first and second step portions, the first and second step portions having a slope substantially perpendicular to the upper surface.  
   
   
       98 . The liquid crystal display device of  claim 83 , wherein the stepped edge portion includes a groove for receiving at least one lamp of the light source, the light incident surface includes an inner surface of the groove on which the light is incident.  
   
   
       99 . The liquid crystal display device of  claim 83 , wherein the lamp reflector is slant with respect to the bottom and the side wall of the mold frame to form a space between the lamp reflector and the mold frame, and an electrical line connected to the lamp unit is drawn out through the space that is enclosed with a bottom of the lamp reflector, the sidewall of the mold frame, and a middle chassis securing the light guide plate on the mold frame.  
   
   
       100 . The liquid crystal display device of  claim 83 , wherein the lamp reflector includes: 
 a first reflect portion for receiving a first lamp of the lamp unit and reflecting light from the first lamp;    a second reflect portion for receiving a second lamp of the lamp unit and reflecting light from the second lamp; and    a flat peak connected between the first and second reflect portions to form a channel space under the lamp reflector, an electrical line connected to the lamp unit being drawn out through the channel space,    wherein the lamp reflector is slant such that a slope line connecting longitudinal axes of the first and second lamps forms an obtuse angle with respect to the light reflect surface and an acute angle with respect to the upper surface.    
   
   
       101 . The liquid crystal display device of  claim 83 , wherein the lamp reflector includes: 
 a first reflect panel disposed on the stepped edge portion of the light guide plate such that the at least one lamp is securely received between the light incident surface of the light guide plate and the first reflect panel; and    a second reflect panel extended from a longitudinal edge of the first reflect panel under the light reflect surface of the light guide plate toward first edge surface of the light guide plate,    wherein the stepped edge portion of the light guide plate receives two or more lamps that are arranged such that a line connecting longitudinal axes of the lamps is substantially perpendicular to the upper surface, the first reflect panel being substantially parallel to the line connecting the axes of the lamps and the second reflect panel being substantially perpendicular to the first reflect panel.    
   
   
       102 . The liquid crystal display device of  claim 83 , wherein the stepped edge portion receives the light source so that a size of a bezel of the liquid crystal display device is reduced.