A semiconductor laser device is specified, the semiconductor laser device comprising an active layer having a main extension plane, a first cladding layer and a second cladding layer, the active layer being arranged between the first and second cladding layer in a direction perpendicular to the main extension plane, a light-outcoupling surface parallel to the main extension direction and arranged on a side of the second cladding layer opposite to the active layer, a photonic crystal layer arranged in the first cladding layer or in the second cladding layer, and an integrated optical element directly fixed to the light-outcoupling surface. Furthermore, a method for manufacturing a semiconductor laser device and a projection device are specified.

A method of generating an optical pulse train using spectral extension by optical phase modulation, spectral narrowing by optical phase demodulation, and narrow linewidth optical filtering is disclosed. It is also described that the wavelength selection of light using a chromatic dispersion element between the optical phase modulator can enrich the method. Systems include an in-line optical setup and a ring-type laser cavity for mode-locked laser outputs. The duration with which the electrical signals driving the modulators are opposed determines the line width of the optical pulses, and the opposite repetition of the electrical signals defines the rate of repetition of an optical pulse train generated. Four different arrangements of electrical signals in the time domain or phase domain make it possible to control the generation of optical pulses and the wavelength selection of the light. (i) A signal arrangement comprising sinusoidal electrical signals with a slight frequency difference. (ii) A signal arrangement comprising a phase-shift between electrical signals. (iii) A signal arrangement comprising a phase-shift between electrical signals depending on the amplitude of the bits. (iv) A signal arrangement comprising random electric waves that repeat themselves over a predefined period to allow the insertion of controllable time delays between each other.

An optical member includes: a main body having transparency or heat dissipation properties; an optical film disposed on an upper face of the main body; a metal film disposed on the upper face of the main body in a region other than a region where the optical film is disposed; a surrounding part joined via the metal film; and a wavelength conversion part surrounded by the surrounding part. The wavelength conversion part is positioned inward of a periphery of the optical film in a top view. The wavelength conversion part is not directly bonded to the optical film and the main body.

A photonic integrated circuit-based dual frequency comb source, an integrated system for dual comb spectroscopy and corresponding method are disclosed. The dual comb source includes, on a same substrate of the photonic integrated circuit, a first and second semiconductor integrated mode-locked laser, a master laser, and connection arrangement between the master laser and each of the first and second mode-locked laser. The master laser is configured for generating a lasing line for simultaneous optical injection-locking of the first and second mode-locked laser, the first and second mode-locked laser are configured for generating a first and second frequency comb respectively, and the connection arrangement is suitable for coherently transferring lasing light from the master laser to each mode-locked laser. The mode-locked lasers include a gain section and a saturable absorber section to provide mode-locking, and an extended optical cavity formed in the substrate.

A light pulse source and method for generating repetitive optical pulses are described. The light pulse source includes a continuous wave cw laser device, an optical waveguide optically coupled with the laser device, an optical microresonator, and a tuning device. The optical microresonator coupling cw laser light via the waveguide into the microresonator, which, may include, a light field in a soliton state with soliton shaped pulses coupled out of the microresonator for providing the repetitive optical pulses. The laser device includes a chip based semiconductor laser, the microresonator and/or the waveguide may reflect an optical feedback portion of light back to the semiconductor laser, which may provide self-injection locking relative to a resonance frequency of the microresonator. The tuning device is arranged for tuning at least one of a driving current and a temperature of the semiconductor laser such that the microresonator may provide the soliton state.

It is provided an assembly including an optical material layer composed of a metal oxide, an underlying layer provided over the optical material layer and composed of a metal or a metal silicide, and a resin layer provided over the underlying layer. A mold including a design pattern corresponding with the fine pattern to the resin layer of the assembly to transcript the design pattern to the resin layer. The resin layer and underlying layer are etched to form an opening in the resin layer and underlying layer to expose the optical material layer through the opening. The optical material layer is etched using the underlying layer as a mask to form the fine pattern in the optical material layer.

A semiconductor laser module includes a package; a plurality of semiconductor laser elements provided in the package; a member having a plurality of mounting surfaces on which the semiconductor laser elements are mounted, the mounting surfaces being separated from a bottom surface of the package by respective distances, the distances being gradually different from each other in a manner that the mounting surfaces as a whole form a step-like form; a plurality of lenses collimating respective laser beams emitted from the semiconductor laser elements; a plurality of reflection mirrors reflecting the respective laser beams; a condenser lens unit condensing the laser beams; an optical fiber where the optical beams condensed by the condenser lenses are optically coupled; and an optical filter disposed on optical lines of the respective laser beams reflected by the reflection mirrors and reflecting light having wavelengths different from the wavelengths of the laser beams.

A technology of effectively interrupting light reflected from a wavelength selective filter so as not to be fed back to a laser diode chip in a semiconductor laser package having a function of adjusting a relative intensity ratio of a signal of “1” and a signal of “0” using an optical filter. Since an optical interruption device may effectively interrupt a light feedback to the laser diode chip by adjusting characteristics of a 45 degree partial reflection mirror in an existing TO-can type laser device having the 45 degree partial reflection mirror and additionally disposing one λ/4 waveplate, unlike previously known optical isolators using an existing Faraday rotator, the signals of “1” and “0” may be effectively adjusted in a TO-can type laser device having a small volume, thereby improving a function of communication.

A narrow linewidth laser in which an all-optical feedback line-up is used to improve the linewidth from a conventional laser source, such as a laser diode. The feedback line-up comprises an optical device having a controllable unbalanced optical coupler arranged on a cavity input path to couple a source signal from the laser source into the optical cavity, and to couple a seed signal received back from the optical cavity into the laser source. The seed signal has a lower power than the source signal. The unbalanced optical coupler may be an optical isolator arranged to couple the seed signal into the laser source at a power level selected to promote preferential stimulated emission within a narrower linewidth. By controlling the power of seed signal such that only a small portion thereof influences the lasing cavity, the narrowing effect of the preferential stimulated emission can be enhanced.

A light pulse source and method for generating repetitive optical pulses are described. The pulse source includes a continuous wave (cw) laser device, an optical waveguide optically coupled with the laser device, an optical microresonator, and a tuning device. The optical microresonator coupling cw laser light via the waveguide into the microresonator, which may include a light field in a soliton state with soliton shaped pulses coupled out of the microresonator for providing the repetitive optical pulses. The laser device includes a chip based semiconductor laser, the microresonator and/or the waveguide may reflect an optical feedback portion of light back to the semiconductor laser, which may provide self-injection locking relative to a resonance frequency of the microresonator. The tuning device is arranged for tuning at least one of a driving current and a temperature of the semiconductor laser such that the microresonator may provide the soliton state.