on the light source substrate 4 will not protrude from the through hole 5 a as described below it is possible to prevent the point light source 3 from being damaged while being in contact with the rear frame 1 front frame 2 light guide plate 7 or the like upon assembling the light source device 31 into the display device 32 or in an attempt to remove the light source device 31 the through hole 5 a may be a notch and may have any shape as long as the shape receives a light source the light source substrate cover 5 is made of a plastic resin a metal or a material including a metallic material the light source substrate cover 5 may be formed of a single member or a combination of plural members the light source substrate cover 5 desirably includes a surface formed of a high reflection member in a white color or having a mirror surface so that light emitted from the point light source 3 is directed to the light guide plate 7 as shown in fig2 to 5 the support member 6 is formed in the same size equal to or larger than that of the light source substrate 4 and arranged on the side of the rear surface 42 of the light source.