Lens unit and compact image pickup module

A compact image pickup module, comprising:

• an imaging lens including plural lenses and a ring-shaped lens holding member that is provided at at least one place between said plural lenses and holds at least one of said plural lenses;
• a cylindrical-shaped lens-barrel having a lens holding portion that holds said imaging lens;
• an image pickup element;
• an image pickup element holder which holds said image pickup element and into which said lens-barrel is fitted so as to be rotatable about an optical axis of said imaging lens and movable in a direction of said optical axis of said imaging lens;
• a cylindrical cam which has as an upper surface or a lower surface thereof, an annular cam surface whose center is set at said optical axis of said imaging lens and which is formed in one of said lens-barrel and said image pickup element holder;
• and
• an abutting member that is abutted against said annular cam surface of said cylindrical cam under &Estate where said lens-barrel is fitted into said image pickup element holder and which is formed in the other of said lens-barrel and said image pickup element holder,
• wherein each of said plural lenses includes a lens portion having an optical function and a flange portion on a periphery of said lens portion, said flange portion of each of said plural lenses being fittable to said flange portion of at least one of the other lenses of said plural lenses, or said lens holding portion or an inner surface of said lens-barrel, and lenses which are combined with each other through fitting of said flange portions of said lenses have respective shapes in which optical axes of said lenses coincide each other under a fitting state of said flange portions of said lenses, and wherein said flange portion of one lens of said plural lenses is fitted to said lens holding portion of said lens-barrel and held by said lens holding member in said lens-barrel, at least two lenses of said plural lenses are positioned by abutting said flange portion of one of said at least two lenses against said lens holding member and an inner surface of said lens-barrel and by fitting said flange portion of another one of said at least two lenses to said flange portion of said one of said at least two lenses, and are arranged in said lens-barrel so that said optical axes of said at least two lenses coincide with said optical axis of said one lens held by said lens holding portion of said lens-barrel, and wherein, after focusing is performed through relative rotation of said lens-barrel and said image pickup element holder, said lens-barrel and said image pickup element holder are fixed to each other.

A compact image pickup module, comprising:

• an imaging lens including plural lenses and a ring-shaped lens holding member that is provided at at least one place between said plural lenses and holds at least one of said plural lenses;
• a cylindrical lens holder whose outer wall surface has a first convex portion formed thereon and which includes a cylindrical-shaped lens-barrel having a lens holding portion that holds said imaging lens;
• an image pickup element;
• an image pickup element holder which holds said image pickup element, into which said lens holder is inserted so as to be rotatable about an optical axis of said imaging lens and movable in an optical axis direction of said imaging lens, and whose inner wall surface has a second convex portion formed thereon;
• a coil spring that engages with said first convex portion of said lens holder and said second convex portion of said image pickup element holder and urges said lens holder and said image pickup element holder in a direction in which a distance therebetween is increased;
• a first cylindrical cam that has as an upper surface or a lower surface thereof, an annular cam surface whose center is set at said optical axis of said imaging lens and which gradually increases in height in a circumferential direction, and that is formed in one of said lens holder and said image pickup element holder;
• and
• an abutting member that is abutted against said annular cam surface of said first cylindrical cam under a state where said lens holder is inserted into said image pickup element holder and that is formed in the other of said lens holder and said image pickup element holder,
• wherein each of said plural lenses includes a lens portion having an optical function and a flange portion on a periphery of said lens portion, said flange portion of each of said plural lenses being fittable to said flange portion of at least one of the other lenses of said plural lenses, or said lens holding portion or an inner surface of said lens-barrel, and lenses which are combined with each other through fitting of said flange portions of said lenses have respective shapes in which optical axes of said lenses coincide each other under a fitting state of said flange portions of said lenses, and wherein said flange portion of one lens of said plural lenses is fitted to said lens holding portion of said lens-barrel and held by said lens holding member in said lens-barrel, and
• at least two lenses of said plural lenses are positioned by abutting said flange portion of one of said at least two lenses against said lens holding member and an inner surface of said lens-barrel and by fitting said flange portion of another one of said at least two lenses to said flange portion of said one of said at least two lenses, and are arranged in said lens-barrel so that said optical axes of said at least two lenses coincide with said optical axis of said one lens held by said lens holding portion of said lens-barrel.