Patent ID: 7928547

Claim:
An optical semiconductor device, comprising: a package having a bottom portion and a sidewall portion; a semiconductor chip having an optical element formed on one surface thereof and having an opposite surface to the one surface fixed to the bottom portion of the package; a transparent member fixed to the semiconductor chip so as to cover the optical element; and a sealing resin filling a space between the sidewall portion of the package and a side end face of the transparent member, wherein the sidewall portion has in an upper part thereof an overhang portion that projects toward inside of the package, the transparent member is exposed from a window portion formed by the overhang portion, a top surface of the sealing resin is located between the sidewall portion of the package and the side end face of the transparent member, said top surface of the sealing resin having a first part and a second part, the first part is exposed from the window portion, and the second part is covered by the overhang portion.