Patent ID: 8101967

Claim:
An optical semiconductor package comprising: a base including a ring and a ring-shaped base bottom formed under the ring, the base bottom being larger in internal diameter than the ring; leads each of which comprise an outer lead serving as an external electrode; at least one block that is provided in the base bottom and has a partially exposed top surface in the ring; an element mounting part provided as a region for mounting an optical semiconductor element on the surface of the block exposed in the ring; a lead placement part formed as a region for placing the leads on the top surface of the block with a step formed between the lead placement part and the element mounting part; a sealing material that seals and holds the block and the leads in a region of the base bottom; and a cavity as a region surrounded by a side of the ring and the top surface of the block, wherein at least the top surface of the block is made of an inorganic material having a reflectivity of at least 83% at a light wavelength of 460 nm, and only the top surface of the block is exposed in a bottom of the cavity.