Substrate unit for optical head and method for manufacturing the same

A manufacturing method of a substrate unit for an optical head apparatus, comprising:

• a step of forming a plurality of light reflecting surfaces on one plane of a first member to be processed formed substantially in a rectangular parallelepiped shape;
• a step of attaching one plane of a second member to be processed formed substantially in the rectangular parallelepiped shape to the plane of said first member to be processed with the plurality of light reflecting surfaces formed thereon in the forming step, disposing an adhesive medium in a portion other than said light reflecting surface, and forming a bonded block in which said first and second members to be processed are connected to each other;
• a step of cutting the bonded block formed in the forming step at a predetermined angle with respect to the light reflecting surface, and dividing the bonded block into a plurality of blocks so that one light reflecting surface is included in each block;
• and
• a step of disposing a cut surface of the block obtained in the forming step as a reference surface of a processing, and forming the substrate unit from the block, comprising a light emitting element attachment surface for attaching a light emitting element which emits laser light to said light reflecting surface, and a light detecting element attachment surface for attaching a light detecting element, formed on the same two-dimensional plane as the light emitting element attachment surface, for receiving light incident from the outside.