Abstract: A method for producing semiconductor components on a substrate including photolithographic patterning steps, in which method, on the substrate, a first layer to be patterned is applied and a second layer serving as a mask layer for the first layer to be patterned is applied, wherein a third layer serving as a mask for the second layer is applied, and wherein at least two photolithographic patterning processes are carried out successively for the second layer, wherein, during one of the patterning processes, after the production of a structure made from a photosensitive layer for the provision of a mask layer for a patterning process at the third layer, positive ramp angles ? are produced at the patterning edges of the third layer, as a result of which the structures remaining free, given a thickness h of the third layer, decrease in size by a value D=2*h/tan ?.

Abstract: A semiconductor structure for photon detection, comprising a substrate composed of a semiconductor material having a first doping, a contact region fitted at the frontside of the substrate, a bias layer composed of a semiconductor material having a second doping, which is arranged on the backside of the substrate at a distance from the contact region, wherein the contact region at least partly lies opposite the bias layer, such that an overlap region is present in a lateral direction, a guard ring, which is arranged at the frontside of the substrate and surrounds the contact region, wherein a reverse voltage can be applied between the contact region and the guard ring. In order to enable more cost-effective production, the overlap region has a lateral extent amounting to at least one quarter of the distance between contact region and bias layer.

Abstract: A device for generating light pulses includes a seed laser source for generating input light pulses. An optical pre-amplifier having variable gain receives the input light pulses from the seed laser source. An optical power amplifier receives the light pulses from the optical pre-amplifier and amplifies and compresses the received light pulses. The light pulses are compressed in the optical power amplifier in such a manner that the pulse duration of the output light pulses of the optical power amplifier is tunable via adjusting the gain of the optical pre-amplifier. Wavelength-tunable light pulses are obtained by supplying the output light pulses of the optical power amplifier to a highly non-linear optical fiber.

Abstract: A tunable diode laser system with external resonator in Littrow or Littman configuration has an optical lattice on which the light beam from a laser diode is diffracted, a support element to hold the lattice or to hold a mirror, which reflects the light diffracted by the lattice, and an actuator to change the position of the lattice or the mirror. The tunable diode laser system enables a reliable mode-hop-free tuning and furthermore is easy and economical to realize by having the support element include a carrier, on which the lattice or the mirror is arranged, and a base body, while the actuator acts on the carrier and rests against the base body. The carrier is connected to the base body via linkages, such that a linear deflection of the actuator is transformed into a rotation of the carrier in the plane of the light beam, while the center of rotation lies outside the base body.

Abstract: A device for generating light pulses that are separated in terms of time has a light source that emits a sequence of light pulses. A regulation signal is formed within a regulation circuit from a cycle signal and the light pulse sequence of the light sources via a phase detector. The regulation circuit includes a regulator that generates a setting signal that influences the repeat frequency of the light pulse sequence of the light source.

Abstract: A fiber coupler for coupling light into an optical fiber and/or coupling light out of the fiber, has two holder elements, namely a fiber holder for holding the fiber, and a lens holder for holding a focusing lens. The holder elements are adjustable in the axial and transversal direction, respectively. In order to make such a fiber coupler available, which allows precise adjustment of the position of the focusing lens relative to the fiber, and which is furthermore compact in structure and inexpensive to produce, the holder elements are connected with a base body by way of at least one elastic monolithic joint, in each instance.

Abstract: A device for amplifying light pulses has an optical stretcher, in which the light pulses of a pulsed laser light source are temporally stretched, and an optically pumped amplifier fiber, in which the light pulses are amplified and, at the same time, temporally compressed. In order to improve such a system with regard to the pulse duration and the pulse energy that can be achieved, the amplifier fiber has a positive group velocity dispersion, whereby the amplifier fiber has non-linear optical properties, so that the optical spectrum of the light pulses is broadened during the amplification process, taking advantage of non-linear self-phase modulation.

Abstract: A device for generating tunable light pulses has a non-linear optical fiber. The optical spectrum of femtosecond light pulses can be modified by this optical fiber, taking advantage of solitonic effects. In order to make available such a device, which makes it possible to vary the pulse energy and the wavelength of the light pulses independently of one another, an optical compressor precedes the non-linear optical fiber.

Abstract: The invention relates to a device for the production of tuneable light impulses in a visible spectral range, comprising a laser system (LS) which emits femtosecond light impulses in the infrared spectral range, and an optical frequency converter (FC) for converting the wave lengths of the light impulses into the visible spectral range. According to the invention, the wave length of the light impulse emitted by the laser system can be tuned in order to provide said type of device which can be used as a light source for time-resolved fluorescence spectroscopy. Said device also comprises an optical stretcher which enables the duration of the impulse of the frequency converted light impulse to be increased to at least 1 ps.

Abstract: A design of a vertical cavity surface emitting laser chip suitable for high speed data communication. An intracavity contact to the doped layers of the bottom mirror is formed so that both contacts are on the top epitaxial side of the wafer. These main structural features can be used to reduce the bond pad capacitance by a suitable spatial separation of metallizations of the p and n contact. The bond pads are processed as a short symmetric coplanar line in a ground signal ground configuration which allows flexible device testing and packaging. A significant capacitance between the pads of the center strip and the outer ground strips is avoided by etching the doped semiconductor layers between these strips down to the semi-insulating substrate. This design avoids pad metallizations and the corresponding critical photolithographic steps over large height differences from the vertical cavity surface emitting laser mesa top to the substrate.

Abstract: Method for manufacturing of an optical fiber with a decoupling interface for scattered light to monitor the power of light guided through the optical fiber, where the optical fiber has a core having a first refractive index and a cladding surrounding the core, the cladding having a second refractive index smaller than the first refractive index, and where a portion of the optical fiber is substantially straightly aligned in the region of the decoupling interface, in which method the optical fiber is electro-thermally treated at an intermediate position within the substantially straightly aligned portion such that a partial mixture of core material and cladding material and, thereby, formation of scattering centers occurs in an interface region between the core and said the cladding, thereby forming the decoupling interface for scattered light from the modified intermediate position.

Abstract: The aim of the invention is to provide prior art equipment, especially for firemen, in the form of helmets (2) and/or breathing masks (3) with a display unit for infrared images. A mask (6) for displaying images on a display (20) is provided, whereby the images are recorded by a camera (13). The inventive mask comprises a frame (18) having a seal (17) that, when the mask (6) is used, rests on an assigned bearing surface (5), e.g. the visor (5) of a breathing mask (3), in such a way that a sealed chamber (19) is formed between the mask (6) and the bearing surface (5).

Abstract: A vertical-cavity surface-emitting laser comprises one or more quantum well layers and one or more barrier layers to define an gain region, a first mirror means and a second mirror means, wherein the first and second mirror means define a resonator. Moreover, the vertical-cavity surface-emitting laser further comprises a first indium phosphide layer adjacent to the gain region and a second indium phosphide layer adjacent to the gain region to define a laser cavity.