Microsoft Technology Licensing, LLC

The University of Southampton

Masaaki Sakakura

Richard John Black

Rokas Drevinskas

Thomas Torsten Dr Winkler

Austin N Donnelly

Timothy John Deegan

Ioan Alexandru Stefanovici

Patrick Neil Anderson

Daniel Jonathan Finchley Cletheroe

Peter Kazansky

James Hilton Clegg

Teodora Ilieva

Pablo Rafael Andreas Wilke Berenguer

Bridgette Rosanna Doris Cooper

Erika Blancada Aranas

Yanhao Yu

Lei Wang

David Lara Saucedo

Ariel Gomez Diaz

Hugh David Paul Williams

Philip Athelstan Wainman

Charles Ernest Whittaker

Yuhao Lei

Examples are disclosed that relate to efficiently producing multiple laser beams of a harmonic frequency from a fundamental frequency beam. One example provides a laser system comprising a laser configured to output a fundamental frequency beam, a first harmonic-generation stage, and a second harmonic-generation stage. The first harmonic-generation stage is configured to receive an input of the fundamental frequency beam from the laser, and output from the laser system a first-stage harmonic frequency beam and a first-stage residual fundamental frequency beam. The second harmonic-generation stage is configured to receive an input of the first-stage residual fundamental frequency beam, and to output from the laser system a second-stage harmonic frequency beam.

Generating multiple beams of a harmonic frequency

A method of writing voxels to a substrate using a laser writing system comprises forming a first voxel at a first position in a substrate using a first laser pulse; detecting light emitted or scattered by the substrate as a result of forming the first voxel; determining whether the detected light satisfies a predetermined constraint; and, when the detected light does not satisfy the predetermined constraint, adjusting an amplitude of a second laser pulse. Light emission or scattering from the substrate as a result of forming a voxel is related to the properties of the formed voxel. By monitoring such emission or scattering, it is made possible to compensate for variations in performance of the laser writing system. Also provided herein are a laser writing system and computer program product which implement the method.

Method and system for writing voxels to a transparent substrate

A method of fabricating an optical element includes providing a substrate of a transparent material in which is to be formed a plurality of birefringent nanostructures spaced apart; generating from the output of a source of femtosecond laser pulses a laser beam group comprising a plurality of focused seeding beams having a circular polarisation; directing the laser beam group onto the surface of the substrate at a first position and applying one or more femtosecond laser pulses from each beam to corresponding volumes in the substrate; repeatedly translating the laser beam group relative to the substrate parallel to the line of seeding beams; translating the laser beam group relative to the substrate and repeating the repeated translation and application of the femtosecond laser pulses; wherein the relative translation of the laser beam group and the substrate aligns the writing beam with successive corresponding volumes.

Method of forming birefringent structures in an optical element

A method for forming birefringent voxels comprises simultaneously generating a first seed pulse and a first data pulse. The first seed pulse and the first data pulse are spatially-separated laser pulses having different amplitudes. The first seed pulse is focused at a first seed location, and the data pulse is focused at a first data location. The first seed location and the first data location are separated by a predetermined distance along a scan path, with the first seed location being ahead of the first data location. Subsequently, a second seed pulse and a second data pulse are generated, and focused at a second seed location and second data location, respectively. The second seed and data locations are separated by the predetermined distance. The second data location is the same as the first seed location, resulting in formation of a birefringent voxel.

Method and system for forming birefringent voxels

A method of writing data to a transparent substrate comprises forming a first voxel by focusing a first laser pulse on a first location in a transparent substrate; and forming a second voxel by focusing a second laser pulse on a second location in the transparent substrate. The first laser pulse and the second laser pulse have different amplitudes, resulting in the first and second voxels having different strengths. Also provided are a system useful for implementing the method; an optical data storage medium obtainable by the method; and a method of reading data from the optical data storage medium.

Phase-modulated optical data storage

A method of delivering optical pulses to a substrate comprises directing a focused beam from a source of optical pulses along a propagation direction onto a substrate; moving the substrate relative to the beam in a plane substantially orthogonal to the propagation direction and continuously along a first direction that includes spaced apart row locations on the substrate, and delivering a plurality of optical pulses from source as the beam reaches each row location; and between delivering the optical pulses at consecutive row locations, moving the beam relative to the substrate in one or more successive discrete movements along a second direction in the plane orthogonal to the first direction, to direct the beam to one or more spaced apart column locations on the substrate, and delivering a plurality of optical pulses from the source at each column location.

Method of optical pulse delivery to multiple locations on a substrate

A method of delivering optical energy to a substrate comprises applying a temporal group of optical pulses to a region of the substrate, wherein the temporal group comprises twenty or fewer pulses of a femtosecond pulse duration, arranged as a first subgroup of pulses comprising up to three pulses followed by a second subgroup of pulses comprising the remaining pulses in the temporal group; and wherein energies of the pulses are controlled such that pulses in the first subgroup have a first energy per pulse and pulses in a second subgroup of pulses have a second energy per pulse which is less than the first energy.

Method of pulsed laser irradiation with reduced thermal damage

Growing community of inventors

Cambridge, United Kingdom

Masaaki Sakakura