(EN) A backlight device (12) is provided with: a side surface emission-type LED (20); a light guide plate (40) provided with a light entrance end surface (41), a light exit plate surface (42), and an opposite plate surface (43); and an LED substrate (30) of which the substrate surface (30a) is attached to an end (43a) of the opposite plate surface (43) of the light guide plate (40). A gap G of at least0.1 mm but not more than 0.2 mm is provided between a light emission surface (25) of the LED (20) and the light entrance end surface (41) of the light guide plate (40). An end (25a) of the light emission surface (25) is provided in a position set back inwards from an end (41a) of the light entrance end surface (41) in the plate thickness direction of the light guide plate (40), by [delta]D1 mm. An end (25b) of the light emission surface (25) is provided in a position set back inwards from an end (41b) of the light entrance end surface (41) by [delta]D2 mm. A configuration is employed which satisfies the relational expressions [delta]D2>/=[delta]D1 and [delta]D2>/=0.1.
(ZH) 背光装置(12)具备：侧面发光型LED(20)；导光板(40)，具有入光端面(41)、出光板面(42)及相反板面(43)；以及LED基板(30)，基板面(30a)安装于导光板(40)的相反板面(43)中的端部(43a)；在LED(20)的发光面(25)与导光板(40)的入光端面(41)之间具有0.1mm以上且0.2mm以下的间隙G，在导光板(40)的板厚方向上，发光面(25)的端部(25a)配置于从入光端面(41)的端部(41a)起向内侧后退了ΔD1mm的位置，发光面(25)的端部(25b)配置于从入光端面(41)的端部(41b)起向内侧后退了ΔD2mm的位置，且设为满足ΔD2≧ΔD1且ΔD2≧0.1的关系式的构成。
