Device for holding an imaging lens

摘要

An imaging lens holder device for use in an optical information recording apparatus is disclosed. The device comprises a focus adjusting member having a coefficient of thermal expansion with a value larger than that of the coefficient of thermal expansion of a supporting leg with a ledge and a leg member for supporting a holder for a member to be scanned. Respective leg materials are so selected that an increment caused by thermal expansion between the surface of the ledge opposite to the substrate and the surface of the member to be scanned and an increment of the focus adjusting member in the direction to the substrate caused by thermal expansion in case of using the ledge surface as a reference surface, are made equal to each other.