Substrate unit and substrate assembly, and camera module using same

A substrate unit, comprising:

• a first printed circuit board;
• and
• a flexible printed circuit board coupled to the first printed circuit board,
• wherein the first printed circuit board comprises a first lateral surface, a second lateral surface disposed further inward than is the first lateral surface, and a third lateral surface disposed further outward than is the second lateral surface,
• wherein the first lateral surface is an outermost lateral surface of the first printed circuit board, and
• wherein the third lateral surface is overlapped with the flexible printed circuit board.

A substrate unit, comprising:

• a first printed circuit board;
• and
• a flexible printed circuit board coupled to the first printed circuit board,
• wherein the first printed circuit board comprises a first lateral surface and a recess formed on the first lateral surface,
• wherein the recess of the first printed circuit board comprises a first bottom surface formed a first depth from the first lateral surface of the first printed circuit board, and a second bottom surface formed at a second depth,
• wherein the second depth is greater than the first depth, and
• wherein the flexible printed circuit board is overlapped with the first bottom surface of the recess of the first printed circuit board.