A level converter for interfacing two circuits supplied by different supply voltages, and integrated circuit including the level converter interfacing circuit in two different voltage islands. The HDD filler has a frame body, a guiding device, and a gravitational sliding device, wherein the frame body defines a bottom surface and a top surface corresponding to the bottom surface. The implant supports surrounding tissue upon implantation, while allowing for in-growth of fibrous tissue to replace the implant. There are a first light emitting region 161 that emits light of the first color and a second light emitting region 162 that emits light of the second color within the same opening 11 of each pixel 10.