Lens moving apparatus
Disclosed is a lens moving apparatus including a housing supporting driving magnets, a bobbin including a coil disposed on the outer surface thereof inside the driving magnets, and moving in a first direction parallel with an optical axis within the housing by electromagnetic interaction between the driving magnets and the coil, and a sensing unit sensing a movement of the bobbin in the first direction.
1. A lens moving apparatus comprising:
a housing;
a base disposed below the housing;
a bobbin disposed inside the housing, and configured to move in a first direction along or parallel with an optical axis within the housing;
a driving magnet disposed on the housing;
a coil provided at an outer surface of the bobbin;
an elastic member supporting the bobbin;
a sensing magnet coupled to the bobbin; and
a position sensor disposed at a position corresponding to the sensing magnet and coupled to a printed circuit board, wherein the position sensor is configured to sense a displacement of the sensing magnet in the first direction,
wherein the bobbin further comprises a reception recess formed on the outer surface of the bobbin to receive the sensing magnet, and
wherein the sensing magnet is disposed in the reception recess and the coil is disposed between the sensing magnet and the position sensor.
2. The lens moving apparatus according to claim 1 , wherein the reception recess comprises an opening connecting any one of an upper surface and a lower surface of the bobbin.
3. The lens moving apparatus according to claim 1 , wherein the reception recess comprises an opening connecting the upper surface of the bobbin such that the sensing magnet is exposed outside the bobbin through the opening.
4. The lens moving apparatus according to claim 1 , wherein an additional reception recess is formed on the outer surface of the bobbin at a position opposite to the reception recess with respect to a center of the bobbin.
5. The lens moving apparatus according to claim 1 , wherein the base comprises a guide member protruding in an upward direction, and the housing comprises a lower guide groove, and
wherein the housing is disposed on the base and the guide member is combined with the lower guide groove.
6. The lens moving apparatus according to claim 1 , wherein the printed circuit board comprises a plurality of terminals configured to be connected to an external power source, and
wherein the plurality of terminals are disposed at one side surface of the base.
7. The lens moving apparatus according to claim 1 , wherein the reception recess comprises an inner surface supporting one surface of the sensing magnet and an adhesive groove depressed more inwardly than the inner surface to a designated depth and an adhesive agent is disposed in the adhesive groove.
8. The lens moving apparatus according to claim 7 , wherein the adhesive groove comprises a first additional groove formed to have a greater length than a length of the sensing magnet in the first direction.
9. The lens moving apparatus according to claim 8 , wherein the adhesive groove comprises a second additional groove formed from an opening to a designated depth in an inward direction of the bobbin.
10. The lens moving apparatus according to claim 4 , further comprising a weight balance member received in the additional reception recess, and
wherein the weight balance member has a same weight as the sensing magnet.
11. The lens moving apparatus according to claim 1 , wherein the driving magnet is provided in a pair and disposed on both opposite sides of the housing, and the position sensor is a hall sensor provided on another side of the housing except for the side surfaces.
12. The lens moving apparatus according to claim 1 , further comprising a cover member receiving the housing and the bobbin,
wherein the position sensor is provided inside the cover member.
13. The lens moving apparatus according to claim 1 , wherein the driving magnet has a rectangular parallelepiped structure having a designated width and is disposed in a magnet through hole or a magnet recess of a side surface of the housing.
14. The lens moving apparatus according to claim 1 , further comprising magnetic bodies provided between the driving magnets and the coil so as to be mounted on the driving magnets and to surface-contact the coil.
15. The lens moving apparatus according to claim 1 , wherein the sensing magnet does not protrude from an outer side surface of the bobbin.
16. A camera module comprising an image sensor, a lens and a lens moving apparatus according to claim 1 .
17. The camera module according to claim 16 , further comprising a substrate coupled to the image sensor and a controller mounted on the substrate.
18. The camera module according to claim 17 , further comprising a sensor holder disposed between the lens moving apparatus and the substrate and the image sensor is disposed between the sensor holder and the substrate.
19. A camera phone comprising the camera module according to claim 18 .