Lens driving device and portable equipment with camera
A lens driving device includes a moving body having a lens and a drive magnet that is moveable with the lens in an optical axis direction of the lens, and a fixed body that moveably supports the moving body in the optical axis direction. The fixed body includes a first drive coil and a second drive coil that are disposed in the optical axis direction and form magnetic circuits with the drive magnet, and a first magnetic member and a second magnetic member that are disposed opposite the first drive coil and the second drive coil, respectively. The moving body is retained at a first position by magnetic attraction working between the drive magnet and the first magnetic member when energization of the first drive coil is stopped. The moving body is also retained at a second position by magnetic attraction working between the drive magnet and the second magnetic member when energization of the second drive coil is stopped.
1. A lens driving device comprising:
a moving body having a lens and a drive magnet that is moveable with the lens in an optical axis direction of the lens; and
a fixed body that moveably supports the moving body in the optical axis direction, the fixed body including a first drive coil and a second drive coil that are disposed apart from each other in the optical axis direction so as to have a gap between the first drive coil and the second drive coil and form magnetic circuits with the drive magnet, and
a first magnetic member and a second magnetic member that are disposed opposite the first drive coil and the second drive coil, respectively,
wherein the drive magnet is disposed in the gap between the first drive coil and the second drive coil, and the drive magnet is moved in the optical axis direction to a first specified position which is nearer to the first drive coil and the first magnetic member or to a second specified position which is nearer to the second drive coil and the second magnetic member; and
wherein the drive magnet is moved to the first specified position together with the moving body through energization of the first drive coil, and the moving body is retained at the first specified position by magnetic attraction working between the drive magnet and the first magnetic member after energization of the first drive coil is stopped.
2. A lens driving device according to claim 1 , wherein the drive magnet is moved to the second specified position together with the moving body through energization of the second drive coil, and the moving body is retained at the second specified position by magnetic attraction working between the drive magnet and the second magnetic member after energization of the second drive coil is stopped.
3. A lens driving device according to claim 1 , wherein the moving body is moved between the first drive coil and the second drive coil through energization of both of the first drive coil and the second drive coil.
4. A lens driving device according to claim 1 , wherein the moving body includes a cylindrical lens barrel that retains the lens, and the drive magnet is affixed in one piece to an outer circumference of the lens barrel.
5. A portable equipment with a camera comprising:
a camera unit; and
a lens driving device mounted on the camera unit, wherein the lens driving device comprises a moving body having a lens and a drive magnet that is moveable with the lens in an optical axis direction of the lens, and
a fixed body that moveably supports the moving body in the optical axis direction, the fixed body including a first drive coil and a second drive coil that are disposed apart from each other in the optical axis direction so as to have a gap between the first drive coil and the second drive coil and form magnetic circuits with the drive magnet,
and a first magnetic member and a second magnetic member that are disposed opposite the first drive coil and the second drive coil, respectively,
wherein the drive magnet is disposed in the gap between the first drive coil and the second drive coil, and the drive magnet is moved in the optical axis direction to a first specified position which is nearer to the first drive coil and the first magnetic member or to a second specified position which is nearer to the second drive coil and the second magnetic member, and
wherein the drive magnet is moved to the first specified position together with the moving body through energization of the first drive coil, and the moving body is retained at the first specified position by magnetic attraction working between the drive magnet and the first magnetic member after energization of the first drive coil is stopped.
6. A portable equipment with camera according to claim 5 , wherein the drive magnet is moved to the second specified position together with the moving body through energization of the second drive coil, and the moving body is retained at the second specified position by magnetic attraction working between the drive magnet and the second magnetic member after energization of the second drive coil is stopped.
7. A portable equipment with camera according to claim 5 , wherein the moving body is moved between the first drive coil and the second drive coil through energization of both of the first drive coil and the second drive coil.
8. A portable equipment with camera according to claim 5 , wherein the moving body includes a cylindrical lens barrel that retains the lens, and the drive magnet is affixed in one piece to an outer circumference of the lens barrel.
9. A portable equipment with a camera comprising:
a lens driving device defining an object lens side and an inner side opposite the object lens side,
the lens driving device comprising a moving body having a lens and a drive magnet that is moveable with the lens in an optical axis direction of the lens,
and a fixed body that moveably supports the moving body in the optical axis direction, the fixed body including a first drive coil and a second drive coil that are disposed apart from each other in the optical axis direction so as to have a gap between the first drive coil and the second drive coil and form magnetic circuits with the drive magnet,
and a first magnetic member and a second magnetic member that are disposed opposite the first drive coil and the second drive coil, respectively,
wherein the drive magnet is disposed in the gap between the first drive coil and the second drive coil, and the drive magnet is moved in the optical axis direction to a first specified position which is nearer to the first drive coil and the first magnetic member or to a second specified position which is nearer to the second drive coil and the second magnetic member, and
wherein the drive magnet is moved to the first specified position together with the moving body through energization of the first drive coil, and the moving body is retained at the first specified position by magnetic attraction working between the drive magnet and the first magnetic member after energization of the first drive coil is stopped;
a cover disposed on the object lens side of the lens driving device, and having an outer surface that is exposed, wherein the cover transmits light from outside and seals an interior of the lens driving device;
an image pickup element that is disposed on an opposite side of the covet in the optical axis direction with the lens of the lens driving device interposed in between; and
a circuit substrate that is connected to the image pickup element, wherein the circuit substrate is disposed in the rear of the lens driving device within a diameter of the lens driving device.