Patent attributes
An auto-focusing camera includes a pair of drive units (100, 200) arranged back-to-back. Each one of the drive units includes a lens unit (11), a permanent magnet (12) mounted around the lens unit, upper and lower coil seats (15a, 15b) arranged at upper and lower sides of the permanent magnet, and upper and lower coils (14a, 14b) wound around the upper and lower coil seats, respectively. The upper and lower coils are used for inducing the upper and lower yokes (10c, 10d) to generate magnetic fields when electric currents are applied to the first and second coils. The magnetic fields generated by the upper and lower yokes interact with the magnetic field of the permanent magnet to drive the lens unit into movement between its focal points. The permanent magnet is fixed to and telescopes inwardly or outwardly with the lens unit.