Abstract: A device for detecting disk asperities. The device includes an optical glide head. The glide head is not required to physically contact a disk for detection of the disk asperities. The optical glide head includes a waveguide configured to transmit light onto the disk and receive reflected light from the disk.

Abstract: A device for detecting disk asperities. The device includes an optical glide head. The glide head is not required to physically contact a disk for detection of the disk asperities. The optical glide head includes a waveguide configured to transmit light onto the disk and receive reflected light from the disk.

Abstract: The media heating device of the magnetic head includes an optical resonant cavity produces a high intensity near-field optical beam of subwavelength dimension adjacent to the write pole. A suitable resonant cavity may be a spherical cavity, disk shaped cavity, ring shaped cavity, racetrack shaped cavity, micropillar cavity, photonic crystal cavity and Fabry-Perot cavity. The cavity is fabricated as a planar thin film structure in layers that are generally parallel to the magnetic pole thin film layers of the magnetic head, such that the principal axis of the resonant cavity is parallel to the air bearing surface (ABS). Optical energy is coupled into the resonant cavity through a waveguide that is placed proximate the cavity, and optical energy is coupled out of the cavity through an aperture that is placed within the cavity. A preferred embodiment may include a nano-aperture disposed between the resonant cavity and the ABS.

Abstract: A subwavelength aperture includes a plurality of ridges that project from an aperture sidewall into the aperture opening. The ridges may be closely spaced such that the hot spots associated with the ridges are likewise closely spaced and create an elongated hot spot. The subwavelength aperture of the present invention may be adapted for use in a magnetic head of a hard disk drive for improved thermally assisted recording (TAR) of magnetic data bits. Such a magnetic head may include an optical resonant cavity that is fabricated within the magnetic head structure.

Abstract: An apparatus for producing a heat affected zone in at least one thin surface layer of metal of a component suitable for use in an HDD comprises: a radiation device for generating a first beam of pulsed laser radiation; an optical device for transmitting the first beam of pulsed laser radiation to the metal on the surface of the component; a first control system for determining the amount of the pulsed laser radiation required to produce a controlled heat affected zone in at least one thin surface layer of metal of the component; and a second control system for determining the location of the pulsed laser radiation on the surface of the component. The embodied apparatus does not require CW laser radiation in conjunction with the pulsed laser radiation to cause bi-directional angular deflection of a free end of the component.

Abstract: An ohmic contact for a silicon slider body is disclosed. A scanned laser beam locally heats a metal film on the slider body to interdiffuse the metal and silicon while minimizing the total thermal load on the slider body. This localized heating avoids thermal damage to the sensitive magnetic head region on the slider. The native oxide layer on the slider is removed by a sputter etch, followed by deposition of a diffusion layer. A capping layer is then deposited to reduce oxidation during subsequent processing. The metal layer is then locally annealed by scanning the laser beam over the target area. Contact resistance of less than 100 ohms is achieved while minimizing the thermal load on the slider body.

Abstract: An optical recording head including a media heating device to write and read data to a heat sensitive optical media disk. The media heating device includes an optical energy resonant cavity that produces a high intensity near-field optical spot of subwavelength dimension. Optical energy is coupled into the resonant cavity through a waveguide that is placed proximate the cavity, and optical energy is coupled out of the cavity through an aperture that is placed proximate an antinode or post within the cavity. In reading data from the optical media, a photodetector is placed at the end of the waveguide. Optical energy emitted from the end of the waveguide is influenced by the reflectivity of the media data bit, and is interpreted as the data bit signal.

Abstract: A magnetic head including a media heating device including an optical cavity resonator that produces a high intensity near-field optical beam adjacent to the write pole. Optical energy is coupled into the resonant cavity through a waveguide that is placed proximate the cavity, and optical energy is coupled out of the cavity through an aperture that is placed proximate an antinode or post within the cavity. The write pole tip may serve as the post in certain embodiments. The media heating device is preferably fabricated between the first and second magnetic pole layers of a perpendicular magnetic head and close to the ABS surface of the head. An alternative embodiment may include a near field aperture disposed between the resonant cavity and the ABS.

Abstract: A hermetic sealing approach involves welding an Aluminum cover onto a low-cost Aluminum housing. According to an example embodiment of the present invention, a metal housing having a base and sidewalls extending upward therefrom is adapted to receive and couple to an HDD arrangement. The metal housing is formed using material and processing (e.g., cold formed or die cast Aluminum) that are relatively inexpensive. A feedthrough arrangement including a plurality of communication pins extends through an opening in the base and is coupled thereto, with the communication pins adapted to pass signals between the inside and the outside of the metal housing. A metal cover is welded to an upper portion of the sidewalls and, with the feedthrough arrangement, hermetically seals the metal housing.

Abstract: An inverter circuit has first and second input terminals adapted to be connected to the voltage. First and second switching devices are connected in series at a first junction. The first switching device connected to the first input terminal, and the second switching device adapted to be connected to one side of the load. Third and fourth switching devices connected in series at a second junction. The third switching device is connected to an opposite side of the load, and the fourth switching device connected to the second input terminal. A voltage divider is connected between the first and second input terminals and provides an output potential. A first current steering device is connected between the potential from the voltage divider and the first junction. A second current steering device is connected between the potential from the voltage divider and the second junction.

Abstract: A power supply suitable for use with discharge lamps includes at least one power factor corrector module for connection to a three phase input supply. Each module includes three single phase circuits for connection between a respective pair of phases, each circuit comprising a converter. The output of the three single phase circuits are connected in series. The module further includes control for varying the duty cycle of the converters using a respective reference signal synchronized with the input voltage to the corresponding converter, and inversely proportionally to a measured instantaneous input voltage to the corresponding converter. Each reference signal is sinusoidal and the control varies the duty cycle of each of the converters proportionally to the square of the respective sinusoidal reference signal. The current drawn by each converter is sinusoidal, even if the mains contains distortions.

Abstract: An inverter circuit has first and second input terminals adapted to be connected to the voltage. First and second switching devices are connected in series at a first junction. The first switching device connected to the first input terminal, and the second switching device adapted to be connected to one side of the load. Third and fourth switching devices connected in series at a second junction. The third switching device is connected to an opposite side of the load, and the fourth switching device connected to the second input terminal. A voltage divider is connected between the first and second input terminals and provides an output potential. A first current steering device is connected between the potential from the voltage divider and the first junction. A second current steering device is connected between the potential from the voltage divider and the second junction.

Abstract: A power supply suitable for use with discharge lamps includes at least one power factor corrector module for connection to a three phase input supply. Each module comprises three single phase circuits for connection between a respective pair of phases, each circuit comprising a converter. The output of the three single phase circuits are connected in series. The module further includes control for varying the duty cycle of the converters using a respective reference signal synchronized with the input voltage to the corresponding converter, and inversely proportionally to a measured instantaneous input voltage to the corresponding converter. Each reference signal is sinusoidal and the control varies the duty cycle of each of the converters proportionally to the square of the respective sinusoidal reference signal. The current drawn by each converter is sinusoidal, even if the mains contains distortions.