Backlight device

1. A backlight device, wherein light emitted from a light source is output toward a rear face of a display panel, comprising:

a plurality of prism films, each including a first face on the display panel side and a second face opposing the first face, wherein a prism-like pattern is formed on the first face, and

a reflector plate including a reflection face opposing the second face, wherein a scattering pattern is formed on the reflection face

wherein,

for each of the plurality of prims films when a first normal line axis of a slope forming the prism-like pattern and a second normal line axis of one slope forming the scattering pattern are projected on an imaginary plane parallel to the display panel, the projected first and second normal line axes form an acute angle.

2. The backlight device according to claim 1 , wherein the angle formed by the projected first and second normal line axes is from 5 to 85 degrees.

3. The backlight device according to claim 2 , wherein the angle formed by the projected first and second normal line axes is not less than 25 degrees.

4. The backlight device according to claim 1 , wherein the scattering pattern is a prism-like pattern.

5. The backlight device according to claim 1 , wherein the scattering pattern comprises a plurality of pyramidal protrusions.

6. The backlight device according to claim 1 , wherein the scattering pattern comprises a plurality of pyramidal recesses.

7. The backlight device according to claim 1 , further comprising a light guide provided so as to extend along the reflection face, between the prism film and the reflector plate, wherein

the light source is provided so as to be adjacent to a side face of the light guide.