Daylighting device and daylighting system

A daylighting device comprising:

• a first transparent slat configured to bend an optical path of incident light from an outdoor direction so as to emit the incident light in a prescribed indoor direction;
• a second slat provided below the first transparent slat, the second slat being configured to either block the incident light or transmit the incident light in a diffuse manner;
• a drive mechanism configured to drive at least one of the first and second slats;
• and
• a control unit configured to control the drive mechanism so as to change an angle of inclination of the at least one of the first and second slats in accordance with a position of the sun, wherein:
• the first transparent slat includes a plurality of prismatic structural bodies configured to change a traveling direction of light in a vertical plane;
• and
• the prismatic structural bodies each have at least:
• a first face serving primarily as a reflection face for the incident light and making an angle α with a reference face for the first transparent slat;
• and
• a second face serving as an entrance face or an exit face for the incident light and making an angle β with the reference face.