Abstract: A display device includes: a substrate; a polycrystalline silicon film on the substrate; and a first buffer film between the substrate and the polycrystalline silicon film and having one surface contacting the polycrystalline silicon film and another surface opposite to the one surface, wherein the one surface of the first buffer film has a first root mean square (RMS) roughness range, and the first RMS roughness range is 1.5 nm or less.

Abstract: A monitoring camera capable of preventing light interference from occurring in a capturing unit due to light diffusely reflected from a covering member. The monitoring camera can include an image capturing unit; a lighting unit to emit light in a capturing direction of the capturing unit and to illuminate a monitoring area; a covering member to cover the capturing unit and the lighting unit; and a light guide unit, mounted in the capturing unit, to guide the light diffusely reflected from the covering member so the light does not enter the capturing unit.