A configurable optical driver circuit includes an adjustable current source circuit configurable to drive one of a variety of different types of electrical to optical devices, an adjustable back-termination resistance circuit configurable to provide a back-termination resistance to the one of a variety of different electrical to optical devices, and a programmable memory configured to provide configuration information to the adjustable current source circuit and to the adjustable back-termination resistance circuit to configure the adjustable current source circuit and the adjustable back-termination resistance circuit for operation with the one of a variety of different electrical to optical devices.

A configurable optical driver circuit includes an adjustable current source circuit configurable to drive one of a variety of different types of electrical to optical devices, an adjustable back-termination resistance circuit configurable to provide a back-termination resistance to the one of a variety of different electrical to optical devices, and a programmable memory configured to provide configuration information to the adjustable current source circuit and to the adjustable back-termination resistance circuit to configure the adjustable current source circuit and the adjustable back-termination resistance circuit for operation with the one of a variety of different electrical to optical devices.

A set of consecutive user data wedges are each located between consecutive servo wedges of a heat-assisted recording medium. Test data is written at least every other one of the consecutive data wedges using different laser power values. Based on reading the test data, a nominal laser power is selected for use by the read/write head.

A set of consecutive user data wedges are each located between consecutive servo wedges of a heat-assisted recording medium. Test data is written at least every other one of the consecutive data wedges using different laser power values. Based on reading the test data, a nominal laser power is selected for use by the read/write head.

An apparatus determines that phase errors have exceeded a threshold when reading data previously recorded to a heat-assisted recording medium. In response to the phase errors exceeding the threshold, remedial action is taken to prevent loss of data due changes in power applied to heat the heat-assisted recording medium when recording.

A storage device includes a storage controller configured to operate a heat-assisted magnetic recording head to write data to a band of consecutive data tracks in a consecutive track order while selectively alternating a power level of the heat source when writing to some data tracks of the band.

A system includes a driver and a controller. The driver is configured to output a signal to a preamplifier of a heat source based on a thermal compensation value to cause the heat source to heat a spot on a storage medium. The controller is configured to adjust the thermal compensation value based on a duration for which the heat source is in an active or inactive operational state. The thermal compensation value is indicative of a history of durations that the heat source was in the active or inactive operational state.

A system includes a driver and a controller. The driver is configured to output a signal to a preamplifier of a heat source based on a thermal compensation value to cause the heat source to heat a spot on a storage medium. The controller is configured to adjust the thermal compensation value based on a duration for which the heat source is in an active or inactive operational state. The thermal compensation value is indicative of a history of durations that the heat source was in the active or inactive operational state.

A method includes moving a heat-assisted magnetic recording head relative to a magnetic recording medium comprising a plurality of tracks, the head comprising a reader and a writer including a near-field transducer (NFT) optically coupled to a laser diode, the writer comprising a center which is laterally offset relative to a center of the reader to define a writer-reader offset (WRO) therebetween. Patterns are written to a particular track at a plurality of laser diode current levels. The patterns are read and a WRO value is calculated at a peak amplitude position for each of the laser diode current levels. A slope of the WRO values is determined with the laser current diode levels. A health condition of the NFT is determined by determining if the slope is greater than a predetermined threshold indicative of non-uniform activation across the NFT.

A method for 3D recording of data on a medium formed from a transparent photosensitive material including at least one dopant. The method includes a first step of calibrating and checking a pulsed light source including calibrating the number of pulses, the level of fluence of each pulse emitted and the rate of the pulses and a step of inscribing an area of the material. The fluence of each pulse emitted, the number of pulses and the rate of the pulses are suitable for irradiating the material in the area so as to form fluorescent clusters stabilized from the dopant while minimizing the modification of the refractive index and the absorption coefficient of the medium in a wavelength range from visible to near infrared.