Abstract:
A tunable distributed feedback (DFB) semiconductor laser based on a series mode or a series and parallel hybrid mode. A grating structure of the laser is a sampling Bragg grating based on the reconstruction-equivalent chirp technology. DFB lasers with different operating wavelengths based on the reconstruction-equivalent chirp technology are integrated together by a sampling series combination mode or a series/parallel hybrid mode, one of the lasers is selected to operate via a current, and the operating wavelength of the laser can be controlled by adjusting the current or the temperature, so that the continuous tuning of the operating wavelengths of the lasers can be realized. Various wavelength signals in parallel channels are coupled and then output from the same waveguide. An electrical isolation area (1-11) is adopted between lasers connected in series or lasers connected in series and connected in parallel to reduce the crosstalk between adjacent lasers.
Abstract:
An assembly includes a carrier and a structure having a core formed on the carrier, wherein the core has a longitudinal extension having two end regions, a first end region is arranged facing the carrier and a second end region is arranged facing away from the carrier, the core is formed as electrically conductive at least in an outer region, the region is at least partially covered with an active zone layer, the active zone layer generates electromagnetic radiation, a mirror layer is provided at least in one end region of the core to reflect electromagnetic radiation in a direction, a first electrical contact layer contacts an electrically conductive region of the core, and a second contact layer contacts the active zone layer.
Abstract:
Laser diode apparatus, comprising a carrier (1) having a carrier top (11), a laser diode chip (4) arranged on the carrier top (11) emitting, during operation, electromagnetic radiation through a radiating face (5), which radiating face (5) runs perpendicularly to the carrier top (11), and at least one optical element (6) to deflect at least some of the electromagnetic radiation radiated by the laser diode chip (4) perpendicularly to the carrier top (11). By the use of a plurality of laser diode chips having wavelengths that differ very slightly from one another, speckles can be reduced. By means of a retarder plate (8) between the laser diode chip and the optical element it is possible to influence the polarisation. A polarisation cube enables the deflected light beam bundles to fully cover one another as differently polarised light beam bundles.
Abstract:
Individual channels of a multiplexed laser array in a multi-channel optical transmitter are monitored at an output of an optical multiplexer. The monitoring may be used to confirm proper operation of each of the channels in the multiplexed laser array and/or to perform wavelength locking on each of the channels. Monitoring at the output of the optical multiplexer avoids the use of multiple photodetectors coupled directly to multiple lasers in the multiplexed laser array. The multiplexed laser array generally includes a plurality of laser emitters optically coupled to an optical multiplexer such as an arrayed waveguide grating (AWG). An optical transmitter with a monitored multiplexed laser array may be used, for example, in an optical line terminal (OLT) in a wavelength division multiplexed (WDM) passive optical network (PON) or in any other type of WDM optical communication system capable of transmitting optical signals on multiple channel wavelengths.
Abstract:
An optical assembly that installs red, green, blue laser diodes (LDs) within a single package is disclosed. The LDs are mounted on a base via respective sub-mounts. Light emitted from the LDs is collimated by collimating lenses and multiplexed by two wavelength filters so as to align optical axes of the light. The multiplexed light has an axis substantially leveled with the axes of the red, green, and blue light measured from the top of the base.
Abstract:
A photon source comprising a quantum structure capable of defining one or more quantum levels such that a photon may be emitted from the quantum structure due to a transition between at least two quantum levels, a control signal configured to vary the transition energy, the transition energy being the energy separation between the at least two quantum levels; and a laser input beam configured to irradiate the quantum structure, the control signal being configured to bring the transition energy into resonance with the laser input beam and out of resonance with the laser input beam, such that the transition energy is resonant with the energy of the laser input beam for a time less than the time to output two photons from the transition.
Abstract:
The invention relates to bi-directional long-cavity semiconductor lasers for high power applications having two AR coated facets (2AR) to provide an un-folded cavity with enhanced output power. The lasers exhibit more uniform photon and carrier density distributions along the cavity than conventional uni-directional high-power lasers, enabling longer lasers with greater output power and lasing efficiency due to reduced longitudinal hole burning. Optical sources are further provided wherein radiation from both facets of several 2AR lasers that are disposed at vertically offset levels is combined into a single composite beam.
Abstract:
An arbitrary waveform generator modifies the input signal to a laser diode driver circuit in order to reduce the overshoot/undershoot and provide a “flat-top” signal to the laser diode driver circuit. The input signal is modified based on the original received signal and the feedback from the laser diode by measuring the actual current flowing in the laser diode after the original signal is applied to the laser diode.
Abstract:
A precision die-attach system and method are provided for precisely aligning and orienting multiple dies relative to one another and relative to a mounting surface and for attaching the dies to the mounting surface while maintaining the relative alignment and orientation. The system includes an alignment tool that is a precisely manufactured part having receptacles formed therein that are precisely aligned with one another. The receptacles hold the respective dies in positions and with orientations that are precisely aligned and oriented with the respective receptacles. Because the receptacles are precisely aligned and oriented relative to one another, the respective dies held therein are precisely aligned and oriented relative to one another. The die-attach system includes a mechanism for maintaining the precise alignment and orientation of the dies within the respective receptacles as the system places the dies on the mounting surface.
Abstract:
A surface emitting laser apparatus is formed using a patterned silicon-on-insulator (SOI)-like substrate which is patterned with a buried sub-wavelength high contrast grating and adapted for bonding of a half-VCSEL device containing at least an active region and an upper mirror, to create a VCSEL. The wavelength of the VCSEL, or any individual VCSEL within an array of VCSEL devices, can be set in response to changing HCG characteristics of the lower mirror in the SOI-like substrate, or in the region above the lower mirror within the half-VCSEL. The inventive VCSEL device and fabrication method are beneficial for a number of application and devices.