Boundary of Light and Shadow begins with a simple relationship: wherever light illuminates, shadow inevitably arises. A strong directional beam creates a deep shadow on the opposite side. The more intense the light, the denser the darkness. To illuminate is also to conceal.  Under the theme of “illuminating darkness,” the work does not erase shadow but instead heightens it. The device is reconstructed as an architectural element, focusing the light source into a single point that draws a sharp dividing line. Crossing that line, the atmosphere shifts into a different quality.  The title refers to the boundary generated between light and shadow. As Jun’ichirō Tanizaki wrote in In Praise of Shadows, darkness is not mere absence. This work presents that relationship as experience. By allowing light and darkness to coexist, it introduces layered depth into space.