Patent ID: 7755856

Claim:
A lens module comprising: a first lens comprising a first central round portion and a peripheral portion, the peripheral portion having a first radially extending portion surrounding the first central round portion, a first axially extending portion extending axially from the first radially extending portion in a first direction, and a second axially extending portion extending axially from the first radially extending portion in a second direction opposite to the first direction, the first radially extending portion comprising a first surface, the first axially extending portion comprising a cylindrical first inner side surface and a second inner side surface, the cylindrical first inner side surface being interconnected between the second inner side surface and the first surface, the cylindrical first inner side surface being coaxially aligned with a principal axis of the first central round portion, and the second inner side surface being inclined relative to the principal axis of the first central round portion, the first radially extending portion further comprising a second surface facing away from the first surface, the second axially extending portion comprising a cylindrical third inner side surface and a fourth inner side surface, the cylindrical third inner side surface being interconnected between the fourth inner side surface and the second surface, the cylindrical third inner side surface being coaxially aligned with the principal axis of the first central round portion, and the fourth inner side surface being inclined relative to the principal axis of the first central round portion; a second lens comprising a second central round portion and a second radially extending portion surrounding the second central round portion, the second radially extending portion a cylindrical first outer side surface coaxially aligned with a principal axis of the second central round portion, the second lens being engaged in the first lens in a manner that the cylindrical first outer side surface contacts the cylindrical first inner side surface of the first lens; and a third lens comprising a third central round portion, a third radially extending portion surrounding the third central round portion, and a third axially extending portion extending axially from the third radially extending portion, the third axially extending portion having a cylindrical second outer side surface, the third lens being engaged in the first lens in a manner that the cylindrical second outer side surface of the third lens contacts the cylindrical third inner side surface of the first lens, the third radially extending portion having an outer diameter substantially equal to an outer diameter of the second axially extending portion.