The present embodiment relates to a lens driving device comprising: a housing; a bobbin disposed in the housing; a magnet and a dummy member, arranged at the housing; a first coil disposed on the bobbin; and a substrate comprising a second coil facing the magnet, wherein the housing comprises a first and a second side part facing each other and a third and a fourth side part facing each other, the magnet comprises a first magnet unit disposed at the first side part, a second magnet unit disposed at the third side part, and a third magnet unit disposed at the fourth side part, and the dummy member is disposed at the second side part.

A valve includes an electrodynamic actuator which has a magnet arrangement for generating a magnetic field and a control element movable relative to the magnet arrangement. The control element includes an energizable coil which is arranged in the magnetic field and is firmly coupled to a coil carrier. The control element is movable between at least two defined positions. There are provided permanent-magnetically interacting holding force which retain the control element in at least one of the defined positions, even when the coil is currentless.

An optical element driving module is provided, including a fixed portion, a movable portion, a driving assembly, and a glue. The fixed portion includes a housing and a base. The movable portion is movable relative to the fixed portion, and the driving assembly includes at least a coil and at least a magnetic element for driving the movable portion to move relative to the fixed portion. Specifically, the housing, the base, and the magnetic element are adhered to each other by the glue.

An optical element driving mechanism is provided, including a base, a holder movably coupled to the base for holding an optical element, a casing, a frame, a driving assembly, and an adhering member. The casing has a top wall and a plurality of side walls extending from the edge of the top wall along an optical axis of the optical element, and the top wall is closer to a light-incident end than the base. The frame is disposed on the top wall and has a frame protrusion extending toward the base. The driving assembly is configured to drive the holder to move relative to the base, and an accommodating space is formed between the base, the frame and the casing. The adhering member is disposed in the accommodating space and configured to directly adhere to the base, the frame, the casing, and the driving assembly.

Actuators for rotating an optical-path-folding-element with two, first and second, degrees of freedom in an extended rotation range around two respective rotation axes, folded cameras including such actuators and dual-cameras including a folded camera as above together with an upright camera.

An underwater acoustic source can include a first piston coupled to a second piston and a plurality of linear magnetic actuators directly connected to each of the first piston and the second piston. Each of the plurality of linear magnetic actuators include a linear shaft positioned within the cylindrical magnetic assembly and mounted to the first end of the rigid ferromagnetic housing and the second end of the rigid ferromagnetic housing, such that the linear shaft is stationary, and linear bearings positioned between the cylindrical magnet assembly and the linear shaft to allow the cylindrical magnet assembly to translate along the linear shaft relative to the cylindrical electrical coil, and wherein each of the plurality of linear magnetic actuators is activated, the first piston and the second piston oscillate towards and away from each other, causing acoustic waves to be generated in water.

A speaker module includes a yoke plate, a first speaker including a first magnet coupled to the yoke plate, a diaphragm spaced apart from the yoke plate and a first coil coupled to the diaphragm, and a second speaker including a housing coupled to the yoke plate and on a side of the first speaker, a second coil provided in the housing and coupled to the yoke plate, and a second magnet spaced apart from the second coil in the housing and coupled to the housing.

A positioning system, including: a first plate; a second plate coupled to the first plate and pivotable about an axis; a pair of voice coil actuators configured to rotate the second plate about this axis; and a processor configured to drive currents to the pair of voice coil actuators; wherein the pair of voice coil actuators comprises a first and second magnet structures mounted on the first plate at equal and opposite distance from the axis, and a first and second coils mounted on the second plate and positioned such that the respective first and second magnet structures move in and out of the first and second coils when the second plate rotates about the axis; wherein each of the first and second magnet structures substantially conforms to an arc having a center at the axis and a radius equal to the distance of the magnet structure from the axis.

An active vibration isolation system with a magnetic actuator where the magnetic actuator includes a coil carrier with at least one coil which engages in a magnetic actuator without touching it so that it takes the form of a linear motor. The magnetic actuator has a magnetic shield with an opening through which the coil carrier extends into the magnet carrier.

An electromagnetic sensor includes a first magnetic pack unit and a first magnetic unit. The first magnetic unit forms a first magnetic pack, a second magnetic pack, and a third magnetic pack in a first direction. The structure of the electromagnetic sensor enables even and uniform distribution of the magnetic field on the electrode and provides a good sound effect under different frequencies.