The refractional units are two-dimensional cylinder and were placed to face the sun over Taipei.They can receive sunlight all day and reduce the angle of exit light.

• 其中，偏折元件的外观为二维长柱形，并且沿著台北的东西方向排列，使它在二维视点上都能接受太阳光全天候的照射，并且缩小其出光角度，达到准直的效果。