Pulse stretcher and method

• Main Authors: Op 'T Root, Wilhelmus Patrick Elisabeth Maria, Godfried, Herman Philip
• Format: Patent
• Language: English
• Published: 31.01.2023
• Subjects: APPARATUS SPECIALLY ADAPTED THEREFOR; BASIC ELECTRIC ELEMENTS; CINEMATOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; DEVICES USING STIMULATED EMISSION; ELECTRICITY; ELECTROGRAPHY; FREQUENCY-CHANGING; HOLOGRAPHY; MATERIALS THEREFOR; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; ORIGINALS THEREFOR; PHOTOGRAPHY; PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES,e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTORDEVICES; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

An apparatus (10) for increasing a pulse length of a pulsed radiation beam, the apparatus comprising: a beam splitter (16) configured to split an input radiation beam (18) into a first beam (24) and a second beam (22); an optical arrangement (12, 14), wherein the beam splitter and the optical arrangement are configured such that at least a portion of the first beam is recombined with the second beam into a modified beam after an optical delay of the first beam caused by the optical arrangement; and at least one optical element (30) in an optical path of the first beam, the at least one optical element configured such that the phase of different parts of a wavefront of the first beam is varied to reduce coherence between the first beam and the second beam.