A panel bottom assembly includes a light-blocker with first concave patterns formed on a top surface thereof. A vibration acoustic device is disposed below, and coupled to, the light-blocker. A buffer is disposed below the light-blocker. A bonding is disposed between the light-blocker and the vibration acoustic device. The bonding has second concave patterns formed on a top surface thereof. The second concave patterns are different from the first concave patterns.