Multistage prism window

A multistage prism window comprising:

• a first transparent plate material;
• a second transparent plate material that is disposed substantially parallel to the first transparent plate material and disposed closer to a room side than the first transparent plate material;
• a first prism disposed between the first and second transparent plate materials;
• a non-transmissive member that is provided in a state of being in contact with or being separated from a predetermined surface of the first prism and that does not allow sunlight to be transmitted;
• a second prism disposed closer to the room side than the first prism between the first and second transparent plate materials;
• and
• a reflection member provided in a state of being in contact with or being separated from a predetermined surface of the second prism,
• wherein the first prism collects, onto the non-transmissive member, light whose angle with respect to a normal line of the first and second transparent plate materials is equal to or greater than a first predetermined angle to put an optical path to the room in a blocked state, and transmits light whose angle with respect thereto is smaller than the first predetermined angle, and
• the second prism collects, onto the reflection member, light whose angle with respect to the normal line is smaller than the first predetermined angle and equal to or greater than a second predetermined angle to reflect the collected light to the room side, and transmits light whose angle with respect thereto is smaller than the second predetermined angle.