Provided is a TFT substrate (substrate); a second electrode (vapor-deposited membrane) that is formed on the TFT substrate and includes a protruding portion; and a sealing membrane provided so as to cover the second electrode, wherein, when σ represents an absolute value of a stress of the sealing membrane, t represents a thickness of the sealing membrane, and P represents a sum of a product of an oblique side length and an oblique side slope in a minute region on an oblique side of the protruding portion, a value of an index N expressed by the expression (N=σ·t·P) is less than or equal to 935 MPa·μm2.