Lens unit composed of different materials and camera module and method for manufacturing the same

A lens unit composed of different materials comprising a base and a lens,

• a part of a camera module of a different material from the lens being used as the base, and
• the lens of optical resin being directly replicated on the base such that the lens is integrally formed on the base,
• wherein the base has a through-hole and the lens is formed in and around the through-hole,
• wherein the base has a surface whose flow resistance against flow of liquefied lens-forming material varies according to its position,
• wherein a flow resistance at a relatively-short distance position from a center of the lens is smaller than a flow resistance at a relatively-long distance position from the center of the lens, and
• wherein when the liquefied lens-forming material reaches a boundary between the relatively-short distance position and the relatively-long distance position, the liquefied lens-forming material is subject to increase in flow resistance as large as a difference between the flow resistance at the relatively-short distance position and the flow resistance at the relatively-long distance position against further progress of the liquefied lens-forming material towards the relatively long-distance position.