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The VCM (voice coil motor) operating principle is an application of Fleming's left hand rule. As illustrated in the
diagram below, the VCM is composed of a magnetic circuit and coil assembly. When a current passes through
the coil placed in the magnetic field, the current, magnetic field and force move at right angles to each other.
This results in a force being applied to the coil assembly. This force is proportional to the value of the current
passing through the coil. Because this is efficient, a large force can be generated even with low current levels.
Coil Assembly
Magnetic Circuit
5. The VCM Principle
I : Current
B : Magnetic flux density
F : Force
Force F = BIL
F : Force (N)
B : Magnetic Flux Density (T)
I : Current
L : Total length of coil (m)
Fleming's Left-hand Rule
VCM Cut Away Diagram
