To provide a daylighting prism sheet suppressing a rainbow pattern even under a low solar altitude condition, and achieves sufficient daylighting.
The daylighting prism sheet is used in the daylighting device in which solar light is incident from a prism surface side, and is emitted by changing its optical path. The daylighting prism sheet has a prism row of a plurality of prism-shaped parts having two inclined surfaces with respect to a plane of a transparent substrate on one surface side of a transparent base. An angle of one side apex A formed of the one inclined surface of the prism shaped part and a perpendicular to the plane of the transparent base is 8-60. An angle of one side apex B formed of the other inclined surface of the prism shaped part and the perpendicular is 8-60. An angle of an apex C formed of the two inclined surfaces is 16-89.
KOBAYASHI MASANORI
RYOKO KK
Ishibashi Masayuki
Masaaki Ogata