The courtyard is located in the Beijing Hutong area with only 12㎡. Mirror glass is used on the ground and walls of the yard. When the owner steps into the door, she will be surrounded by the perspective effect of specular reflection, which increases the permeability of the space and gives people a double landscape experience. The unique reflectivity of the mirror allows the surrounding hutongs,trees, and sky to be reflected on the ground of the yard, which brings more possibilities to space. This kind of interaction between virtual and reality is more prominent.