A MEMS tunable VCSEL includes a membrane device having a mirror and a distal-side electrostatic cavity for displacing the mirror to increase a size of an optical cavity. A VCSEL device includes an active region for amplifying light. Then, a proximal-side electrostatic cavity is defined between the VCSEL device and the membrane device is used to displace the mirror to decrease a size of an optical cavity.

A vertical external cavity surface emitting laser (VECSEL) based system in a linear single cavity configuration is configured to deliver light in higher-order Hermite-Gaussian transverse modes with Watt-level output power. Simultaneous and independent lasing of spatially-restructurable multiple high-order transverse modes that are collinearly-propagating at the output of such laser cavity is facilitated with the use of an optical pumping scheme devised to control positions of location at which the gain medium of the system is pumped (e.g., locations of focal spots of multiple pump beams on the gain-medium chip). An external astigmatic mode converter is utilized to convert such high-order Hermite-Gaussian modes into corresponding Laguerre-Gaussian modes.

A very strong selection mechanism is provided in a tunable vertical cavity surface emitting laser (VCSEL) by manipulating the laser threshold to be different for TE and TM polarization by a employing a subwavelength grating in the laser cavity. The laser selects the polarization with the lowest threshold. The grating does not diffract and does not add loss to the cavity. It works by creating a large birefringence layer between the semiconductor and air sub-cavities of the full VCSEL. Multilayer stack calculations show that this results in a lower threshold for the TM polarization over the TE. This subwavelength grating layer, in one embodiment, replaces the AR coating on the semiconductor surface.

The invention relates to a SLED device emitting light from a substrate side, configured to suppress lasing, and comprising a reflective element (55) on a front surface of a substrate (22) configured to redirect an optical beam (light) onto a back surface of the substrate (22). In one embodiment the device can be used for making a compact RGB (red-green-blue) projector.

In an embodiment, a laser apparatus comprises a semiconductor laser, e.g., of the VECSEL type, for generating pulsed laser radiation having a pulse duration in the femtosecond range or shorter and having a pulse repetition rate of at least 100 MHz; a selector for selecting groups of pulses from the laser radiation, each pulse group comprising a plurality of pulses at the pulse repetition rate, wherein the pulse groups are time-displaced by at least 500 ns; a scanner device for scanning a focal point of the laser radiation; a controller for controlling the scanner device based on a control program including instructions that, when executed by the controller, bring about the creation of a LIOB-based photodisruption for each pulse group in a target material, e.g. human eye tissue.

In an embodiment, a laser apparatus comprises a semiconductor laser, e.g., of the VECSEL type, for generating pulsed laser radiation having a pulse duration in the femtosecond range or shorter and having a pulse repetition rate of at least 100 MHz; a selector for selecting groups of pulses from the laser radiation, each pulse group comprising a plurality of pulses at the pulse repetition rate, wherein the pulse groups are time-displaced by at least 500 ns; a scanner device for scanning a focal point of the laser radiation; a controller for controlling the scanner device based on a control program including instructions that, when executed by the controller, bring about the creation of a LIOB-based photodisruption for each pulse group in a target material, e.g. human eye tissue.

A method, system and an apparatus for hybrid optical and electrical pumping of semiconductor lasers and light-emitting diodes (LEDs) improves reliability at high operating temperatures. The semiconductor laser or LED is biased via optical pumping and a relatively small electrical modulation current modulates the laser. At low modulation speeds, the modulation current is substantially lower than that required for biasing the laser or directly modulating it at high speeds. The lifetime of the laser is improved by substantially reducing the operating current, enabling laser lifetimes adequate for operation in many applications, such as deep-hole oil drilling and jet engine control, where operation is not currently possible.

A vertical external cavity surface emitting laser (VECSEL) based system in a linear single cavity configuration is configured to deliver light in higher-order Hermite-Gaussian transverse modes with Watt-level output power. Simultaneous and independent lasing of spatially-restructurable multiple high-order transverse modes that are collinearly-propagating at the output of such laser cavity is facilitated with the use of an optical pumping scheme devised to control positions of location at which the gain medium of the system is pumped (e.g., locations of focal spots of multiple pump beams on the gain-medium chip). An external astigmatic mode converter is utilized to convert such high-order Hermite-Gaussian modes into corresponding Laguerre-Gaussian modes.

A mode-locked solid state laser apparatus including an optical film, a gain medium crystal, a Fabry-Perot element, a first mirror, a second mirror, a third mirror and an output coupler is disclosed. The optical film is configured to receive a pumping light having a first wavelength incident in a first direction. The gain medium crystal receives the pumping light passing the optical film, and generates an initial laser beam having a second wavelength, wherein the initial laser beam forms a first optical path starting at one end thereof from the gain medium crystal. The Fabry-Perot element is disposed on the other end of the first optical path opposite to the one end, and reflects the initial laser beam along a second optical path having one end thereof starting from the Fabry-Perot element. The first mirror is disposed on the other end of the second optical path opposite to the one end of the second optical path, and reflects the initial laser beam along a third optical path having one end thereof starting from the first mirror.

A laser amplifier head is provided. The laser amplifier head includes a plurality of plates of a solid-state laser active medium disposed in a housing, arranged parallel to one another with their main surfaces facing one another, the housing being provided with an inlet port and an outlet port for a cooling liquid, and also at least one window allowing a laser beam to pass through the laser active medium plates, wherein it also includes: a mechanical connection device allowing a cyclic movement at least of the laser active medium plates in relation to the laser beam in a plane (xy) perpendicular to the direction (z) of their thickness; and cooling liquid guide plates arranged in the extension of the laser active medium plates, between the latter and the inlet port of said liquid.