Femtolasers Produktions Gmbh

Femtolasers Produktions Gbmh

Andreas Stingl

Ferenc Krausz

Christian Warmuth

Tuan Le

Andreas Assion

Alfred Tomasch

Harald Frei

Alexander Apolonski

Alexander Fürbach

Andreas Poppe

Karl Unterrainer

Gottfried Strasser

Juraj Darmo

The present disclosure relates to a laser crystal device () for short pulse lasers, comprising a container (), the interior of which is sealed relative to the environment and which contains a technically pure atmosphere with windows () in the side walls () for the passage of laser radiation (), which in operation passes through a laser crystal (), wherein the window () has an inclination of the Brewster angle to the beam path of the laser radiation () and a mounting () for the laser crystal () is provided within the container (), the windows () are inclined to each other by double the Brewster angle and are placed at an adequate distance from the laser crystal () position, with relation to the laser beam properties, wherein the beam cross section at the windows () is sufficiently large in order to guarantee a peak intensity at the windows () which is sufficiently reduced in relation to the peak intensity of the laser beam () at the laser crystal () for avoiding degenerative processes on the windows ().

Laser crystal device

A mode-locked short pulse laser resonator including a pump laser beam input, a non-linear laser medium, a plurality of resonator mirrors as well as a first outcoupler mirror and a second outcoupler mirror, wherein the first outcoupler mirror is arranged for coupling out laser radiation having first spectral properties, and the second outcoupler mirror is arranged for coupling out laser radiation having second spectral properties which are different from the first spectral properties.

Mode-locked short pulse laser resonator and short pulse laser arrangement

A short pulse laser arrangement with, preferably, passive mode-locking, comprising a resonator containing a laser crystal and several mirrors, one of which forms a pump beam coupling-in mirror and one of which forms a laser beam out-coupling mirror, and a multiple reflexion telescope enlarging the resonator length, the resonator in operation having a positive averaged dispersion over a wavelength range concerned; the adjustment of the positive averaged dispersion of the resonator is effected by means of the mirrors of the resonator, at least a few of which are designed as dispersive mirrors.

Short pulse laser device

The invention relates to a short-pulse laser device () with a preferably passive mode coupling. Said device comprises a resonator () which contains a laser crystal () in addition to several mirrors (M-M, OC) that define a long resonator arm () and a short resonator arm (), one (M) of said mirrors forming a pump beam coupling-in mirror and another (OC) forming a laser beam output coupler and comprising a multiple reflection telescope () that increases the length of the resonator and is allocated to the resonator arms (). Said telescope is constructed using mirrors (), in order to reflect a laser beam () that is coupled into the space between them back and forth several times, prior to being decoupled back into the other resonator, whereby sequential eccentric reflection points (to' to&#x2032;) on the mirrors () are offset in relation to one another. The telescope () comprises only one curved mirror (), in addition to a planar mirror (), whose position corresponds at least substantially to the center (&#x2032;) of an imaginary multiple reflection assembly comprising two curved mirrors (), whereby the one curved mirror () of the telescope () also contains the reflection points of the other imaginary curved mirror. The invention also relates to a multiple reflection telescope () for said device.

Short-pulse laser device with a preferably passive mode coupling and multiple reflection telescope therefor

A dental laser arrangement switchable between different modes of operation, the arrangement including a laser device operable as a laser oscillator and as a laser amplifier. The laser device includes a laser resonator having a pump unit and an active modelocker as well as an optic loss element that introduces selective losses in the resonator. The laser arrangement further includes a laser beam-out-coupling unit. The modelocker is connected to a control circuit for switching between a CW-mode of operation for coagulating soft tissue, in which the modelocker is switched off, and two short-pulse modes of operation in which high frequency signals of equal frequencies, but different powers are applied by the control circuit to the modelocker so as to generate laser pulses of a pre-determined duration. One of the two short-pulse modes of operation is provided for ablation of hard tooth tissue, and the other short-pulse mode of operation, in which the laser radiation has a lower peak power in comparison with the first-mentioned short-pulse mode of operation, is for surface sealing of hard tooth tissue. An output of the control circuit furthermore is applied to the activatable optic loss element for controlling the losses in the resonator in the short-pulse modes of operation.

Laser device

The invention relates to a device for generating terahertz (THz) radiation comprising a short pulse laser () with mode coupling to which a pump beam () is supplied, and comprising a semiconductor component equipped with a resonator mirror (M). This semiconductor component serves to derive the THz radiation based on incident laser pulses. The resonator mirror (M), preferably a resonator end mirror, is provided with a semiconductor layer (), which is partially transparent to the laser radiation of the short pulse laser (), whose absorption edge is lower than the energy of the laser radiation of the short pulse laser () and on which the electrodes () that can be connected to a bias voltage source are placed in order to generate and radiate the THz radiation in the electric field.

Device for generating terahertz radiation, and a semiconductor component

A cooling device for an optical amplifier or oscillator has Peltier elements enclosed in a housing with an optical crystal and extract heat from the optical crystal. The housing is sealed and can contain a desiccant for removing moisture and preventing particle deposition. Alternately, the housing can be evacuated with a vacuum to maintain a clean operating environment. The housing holds a Brewster window at a Brewster angle with an inident laser beam to permit passage of the laser beam. The housing also can be arranged on a platform providing liquid cooling.

Cooling device for an optical crystal, or laser crystal

A focussing arrangement, in particular for laser devices ( ), comprising a focussing mirror (M ) arranged on a carrier which is displaceable in one plane, and having a spherical reflecting surface ( ), wherein the displaceable carrier is formed by a rocking member ( ) which is at least approximately Z-shaped when seen in top view, the rocking member having a rocking longitudinal arm ( ) which is articulately connected on both ends to transverse arms ( ), the longitudinal arm carrying the focussing mirror (M ), wherein the transverse arms ( ) are arranged so as to be pivotable about pivot axes perpendicular to the plane of displacement, and wherein the center of curvature (M) of the spherical reflecting surface ( ) of the focussing mirror (M ) lies at least substantially on an axis extending through the geometric center of the longitudinal arm ( ), perpendicular to the plane of displacement.

Focusing device

A cooling device for an optical amplifier or oscillator has Peltier elements enclosed in a housing with an optical crystal and extract heat from the optical crystal. The housing is sealed and can contain a desiccant for removing moisture and preventing particle deposition. Alternately, the housing can be evacuated with a vacuum to maintain a clean operating environment. The housing holds a Brewster window at a Brewster angle with an incident laser beam to permit passage of the laser beam. The housing also can be arranged on a platform providing liquid cooling.

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Korneuburg, Austria

Andreas Stingl