TRUMPF PHOTONIC COMPONENTS GMBH

A vertical-cavity surface-emitting semiconductor laser includes a semiconductor multi-layer structure in which a trench is formed, the trench running in a peripheral direction around a longitudinal center axis which runs perpendicularly to the semiconductor multi-layer structure and forming a mesa from the semiconductor multi-layer structure. The mesa contains a layer which is oxidized from an outer periphery of the mesa perpendicularly to the longitudinal center axis up to a predefined oxidation distance in order to form in the mesa an aperture for narrowing down an electrical and/or optical path. The trench has, in the peripheral direction around the longitudinal center axis, a plurality of portions in which the trench is closer to the longitudinal center axis than in other portions of the trench. The mesa has an inner mesa region and a plurality of support structures which surround the inner mesa region.

A Vertical Cavity Surface Emitting Laser (VCSEL) includes an optical resonator with a first reflector, a second reflector, and an active region for laser emission arranged between the first reflector and the second reflector, and an electrical contact arrangement configured to provide an electrical drive current to electrically pump the optical resonator. The optical resonator further comprises a loss layer introducing optical and electrical losses to increase wavelength shift of the laser emission when varying the drive current. The optical losses introduced by the loss layer are higher than the sum of the optical losses in remaining regions outside the active region. The electrical losses introduced by the loss layer are higher by a factor of at least 5 than the electrical losses in the remaining regions.

A vertical cavity surface emitting semiconductor laser includes a multi-layered semiconductor structure having an optical resonator composed of semiconductor layers, the optical resonator includes a first Bragg mirror, a second Bragg mirror, and an active region between the first Bragg mirror and the second Bragg mirror for generating laser radiation. The active region has a plurality of active layers including a first and at least a second active layer, where the second active layer is a last active layer in front of the second Bragg mirror. A first oxide aperture for current constriction and a first tunnel diode are located between the first active layer and the second active layer, a second oxide aperture is located on a side of the second active layer which is remote from the first active layer. A second tunnel diode is located on the side of the second active layer.

A semiconductor component for emitting light includes a main body that comprises at least one mesa body. The mesa body has an emission region for emitting the light. The emission region is assigned a first mirror portion, a second mirror portion, and an active portion arranged between the two mirror portions and serving to produce the light. The semiconductor component further includes electrical contacts for feeding electrical energy into the active portion, with at least one stress element that is attached to a surface of the main body. The stress element is configured to generate in the main body a material stress which has an effect on one or more polarization properties of the emitted light.

An optoelectronic apparatus is adapted to generate a structured light pattern. The optoelectronic apparatus has: a first array of vertical cavity surface emitting lasers (VCSELs); a first homogenization optics arrangement associated with the first array of VCSELs; a second array of VCSELs; a second homogenization optics arrangement associated with the second array of VCSELs; and a pattern optics arrangement configured to generate a structured light pattern based on a common homogeneous intensity distribution in an intermediate plane. The first homogenization optics arrangement and the second homogenization, each associated with a different one of the first array of VCSELs or the second array of VCSELs, are arranged such that their intensity distributions add up to the common homogeneous top-hat intensity distribution in the intermediate plane.

A method of forming an optical structure in a semiconductor substrate includes applying a layer of photoresist on a surface of the semiconductor substrate, exposing the photoresist with exposure light, and subsequently developing the photoresist. After developing, a remaining layer of the photoresist has a photoresist relief profile. The method further includes etching the photoresist and the semiconductor substrate to transfer the photoresist relief profile into the semiconductor substrate to obtain the optical structure in one or more first sub-areas and a support structure in one or more second sub-areas. A thickness of the layer of the photoresist applied to the surface of the semiconductor substrate is greater than a product of a maximum height difference of a relief profile of the optical structure and a ratio between etch rates of the photoresist and of the semiconductor substrate.

A laser sensor module includes a laser diode configured emit a laser beam, an electrical driver configured to supply the laser diode with a driving current to stimulate emission of the laser beam, a detector, and an optical arrangement configured to focus the laser beam to a focus region. The laser diode is arranged to emit the laser beam through the optical arrangement to the focus region. The optical arrangement comprises an emission window. The detector is arranged to determine an interference signal. The laser sensor module comprises a soiling detection unit configured to vary a wavelength of the laser beam with a variation amplitude over a predetermined time period to provide a soiling detection signal indicative of a soiling of the emission window based on an interference signal during the wavelength variation of the laser beam.

A method of fabricating a Vertical Cavity Surface Emitting Laser(VCSEL) device includes providing a first structure comprising a VCSEL layer structure on a wafer. The first structure has a non-planar first structure top surface with varying height levels and includes one or more electrical contact areas. The method further includes applying one or more layers of cover material on the non-planar first structure top surface with a thickness such that a lowest height level of a cover material top surface is equal to or above the highest height level of the non-planar first structure top surface, to obtain a second structure having a second structure top surface, planarizing the second structure top surface, and producing one or more first electrical vias from the second structure top surface through the one or more layers of cover material for electrical connection to the one or more electrical contact areas.

A method of forming an optical aperture of a vertical cavity surface emitting laser includes the steps of providing a layer stack of semiconductor layers, the semiconductor layers including an intermediate layer comprising a semiconductor material suitable to be oxidized and oxidizing the intermediate layer to an oxidation width so as to form an oxidized outer region and a non-oxidized central region in the intermediate layer. The method also includes removing at least a part of the oxidized outer region so as to form a gap where the oxidized outer region or the part of the oxidized outer region has been removed, depositing an electrically non-conducting material on walls of the gap with a thickness smaller than a thickness of the gap, and filling a remaining void of the gap with a further material.

A method for determining a particle distribution in a particle stream ( 10 ) using a laser apparatus ( 12 ) which has a semiconductor laser ( 14 ) that emits a laser light ( 16 ) having an inhomogeneous intensity profile ( 30 ), characterised by receiving a light reflection ( 20 ) of the laser light ( 16 ) generated at particles ( 18 ) of the particle stream ( 10 ), an evaluation unit ( 22 ) connected to the laser apparatus ( 12 ) evaluating a reflection signal generated by the light reflection ( 20 ) in respect of a frequency distribution of signal strength values which is generated on the basis of the intensity profile ( 30 ) when the particles ( 18 ) penetrate the laser light ( 16 ), a processor unit determining the particle diameters of the individual particles on the basis of the signal strength values, carrying out a diameter correction of at least some of the determined particle diameters on the basis of the sensitivity of the laser apparatus, creating a diameter list of the frequency distribution of the particle diameters, carrying out a frequency correction of the diameter list using a correction list, storing the corrected diameter list on a storage medium.