An optical element driving mechanism is provided. The optical element driving mechanism includes a first holder, a second holder, a plate, a biasing assembly, and an electromagnetic driving assembly. The first holder holds a first optical element with a first optical axis. The second holder holds a second optical element with a second optical axis. The plate is disposed below the first holder and the second holder. The biasing assembly forces the first holder to move relative to the plate on a plane substantially perpendicular to the first optical axis, and includes a biasing element, wherein when a driving signal is applied to the biasing element, a length of the biasing element is changed. The electromagnetic driving assembly forces the second holder to move relative to the plate and comprising a first magnetic element and a coil.

An autonomous search light system for being mounted to an aircraft includes a search light for emitting an adjustable light output; an RF receiver with at least two RF antennas for receiving RF signals emitted by an RF transmitter; and a controller for determining a position of the RF transmitter in relation to the search light from the received RF signals and for controlling the search light based on the determined position of the RF transmitter.

To provide a diffractive optical element having a high light utilization efficiency, whereby light spots having a predetermined pattern can be stably formed, a projection device and a measuring device. The diffractive optical element of the present invention comprises a transparent substrate, a convexo-concave portion formed so as to be in contact with one surface of the transparent substrate and a filling portion with which concave portions of the convexo-concave portions are filled and which covers top surfaces of convex portions of the convexo-concave portion for planarizing the convexo-concave portion, wherein the convexo-concave portion has at least two stages on the surface of the transparent substrate; the top surfaces of the respective stages are parallel to one another; among the transparent substrate, the convexo-concave portion and the filling portion, the refractive indexes of at least the convexo-concave portion and the filling portion are different with respect to the incident light which enters from the normal direction of the surface of the transparent substrate; and the refractive indexes of the transparent substrate, the convexo-concave portion and the filling portion with respect to incident light are at most 2.2.

Electro-magnetic actuators used to provide a displacement of an optical element such as a lens carrier comprise at least one ferromagnetic frame associated with a large air gap and at least one ferromagnetic member parallel to and separated from an elongated section of a frame by a small air gap. Actuation causes a magnetic circuit that appears in the at least one frame, the at least one member and small air gaps and by-passes or bridges the large air gap. In some embodiments, the resultant magnetic force moves the at least one member and leads to the displacement of an optical element attached thereto. In some embodiments, at least one frame and at least one member are arranged to provide a center hole and are dimensioned to enable insertion of a lens carrier in the hole. In some embodiments, the displacement is for auto-focus. In other embodiments, the displacement is for optical image stabilization.

A data storage device is disclosed comprising a head actuated over a disk, and a two-dimensional (2D) equalizer comprising a plurality of coefficients. A plurality of stored coefficients are accessed based on a first off-track offset of the head in order to first initialize the coefficients of the 2D equalizer, and then the coefficients of the 2D equalizer are first adapted based at least on a first read signal to generate first adapted coefficients. The plurality of stored coefficients are accessed based on a second off-track offset of the head in order to second initialize the coefficients of the 2D equalizer, and then the coefficients of the 2D equalizer are second adapted based at least on the first read signal to generate second adapted coefficients.

A hydraulic pump/motor includes a rotational shaft rotatably attached inside a casing, a cylinder block configured to rotate together with the rotational shaft, a plurality of pistons, a swash plate, a valve plate, and a rotation detection mechanism. The rotation detection mechanism includes a detection target section having three or more recesses formed on an outer peripheral surface of the cylinder block in a unique arrangement pattern with different arc lengths between the three continuous recesses with respect to one rotational direction of the rotational shaft and being formed so as not to include the unique arrangement pattern with respect to the other rotational direction of the rotational shaft, each of the three or more recesses having a cross section having a same semicircular shape perpendicular to a direction of the rotational shaft; and a rotation sensor arranged in the casing in a state of facing the detection target section.

In an optical disc apparatus for reproducing information recorded on a track of an optical disc, an optical head irradiates a light beam onto the track, detects a reflected light reflected by the track, and generates a reproduction signal based on the reflected light. A decoder circuit decodes the reproduction signal, and generates a decoded signal including information recorded on the track. A correlation detector circuit calculates a cross-correlation value between the reproduction signal and the decoded signal. A servo circuit detects a deviation amount of an irradiation position of the light beam onto the track, from the reproduction signal, and controls the irradiation position of the optical head based on the cross-correlation value and the deviation amount.

In an optical disc apparatus for reproducing information recorded on a track of an optical disc, an optical head irradiates a light beam onto the track, detects a reflected light reflected by the track, and generates a reproduction signal based on the reflected light. A decoder circuit decodes the reproduction signal, and generates a decoded signal including information recorded on the track. A correlation detector circuit calculates a cross-correlation value between the reproduction signal and the decoded signal. A servo circuit detects a deviation amount of an irradiation position of the light beam onto the track, from the reproduction signal, and controls the irradiation position of the optical head based on the cross-correlation value and the deviation amount.

A disc recorder and player apparatus includes a plurality of recorder and player subsystems, a disc motor, and a controller. Each of the recorder and player subsystems includes a pickup and a traverse motor. When one of the recorder and player subsystems writes or reads data on or from a first track on the disc recording medium, the controller prohibits the other of the recorder and player subsystems from writing and reading data on and from a second track on the disc recording medium as well as moving the pickup to the second track, the second track being at a position different from a position of the first track, and the second track being to be accessed at a rotational speed different from a rotational speed for the first track.

Systems and methods for long-term non-volatile non-rotating optical storage of digital information rely on storage elements that include optical storage media, an access subsystem configured to access bits of information from one of the storage elements, and a support structure configured to support multiple storage elements. A laser used to retrieve and/or record bits of digital information may be moved along two orthogonal dimensions while the storage element is non-rotating.