Patent ID: 8079745

Claim:
A backlight module, comprising: a back plate; a light guide plate provided on the back plate; and a light source provided at a side of the light guide plate, wherein a side and lower surface of the light guide plate facing the light source comprises a concave surface, and wherein a side surface of the back plate facing the side and lower surface of the light guide plate comprises at lease one inclined surface, and the inclined surface is an inclined planar surface parallel to an axis of the light source, wherein a contour of the concave surface satisfies the following formula: y = { ax 4 + bx 3 + cx 2 + dx + e ; ( 0 < x < m , a > 0 , e > 0 ) h max ; ( m ≤ x ≤ n ) aX 4 + bX 3 + cX 2 + dX + e ; ( n < x ≤ L max , X = L max - x , a > 0 , e > 0 ) wherein, x is a length of an upper surface of the light guide plate in an x direction, y is a thickness of the light guide plate; h max is the maximum thickness of the light guide plate in the y direction; h mid is the minimum thickness of the light guide plate in the y direction, which, in actual production, generally is not 0; L max is the maximum length of the upper surface of the light guide plate in the x direction.