<p>A direct-lighting backlight is provided with a back frame (1b) having a bottomed opening; a plurality of fluorescent lamps (2), each of which is arranged in the back frame (1b) and has a diameter(R) of 6.0mm or more; and a diffuser plate (3) arranged on an opening section (1b3) of the back frame (1b). When a pitch of the adjacent fluorescent lamps (2) is expressed as P(mm), an inequality of P=3.5R is satisfied.</p>
