A light emitting apparatus includes: a light emitting element configured to emit laser light; a case configured to house the light emitting element, and including a window configured to allow transmittance of the laser light emitted from the light emitting element; a first optical element provided outside the case and configured to converge, in a fast axis direction, the laser light passing through the window; and a second optical element configured to collimate the laser light input via the first optical element, in the fast axis direction, in a state where a beam width in the fast axis direction is narrower than a beam width in the fast axis direction on an incident surface of the first optical element, the second optical element being located closer to the first optical element than a convergence point of the laser light in the fast axis direction by the first optical element.

Provided are a light source device that is suitable for an optical amplifier including a plurality of optical amplification units and that can emit excitation light of optimal intensity to each of the optical amplification units, and an optical amplifier that uses this light source device. The light source device includes: first and second light sources that each emit excitation light; and a polarization beam combiner that includes first and second input ports and first and second output ports and that multiplexes/demultiplexes the pumping light emitted from the first and second light sources and inputted to the first and second input ports.

Techniques for producing a Brillouin laser are provided. According to some aspects, techniques are based on forward Brillouin scattering and a multimode acousto-optic waveguide in which light is scattered between optical modes of the waveguide via the Brillouin scattering. This process may transfer energy from a waveguide mode of pump light to a waveguide mode of Stokes light. This process may be referred to herein as Stimulated Inter-Modal Brillouin Scattering (SIMS). Since SIMS is based on forward Brillouin scattering, laser (Stokes) light may be output in a different direction than back toward the input pump light, and as such there is no need for a circulator or other non-reciprocal device to protect the pump light as in conventional devices.

A rod-type photonic crystal fiber amplifier includes a signal coupling lens, a first dichroic mirror, a first hollow pump coupling lens, and a rod-type photonic crystal fiber. The rod-type photonic crystal fiber comprises a core and a cladding, wherein signal light is coupled into the core of the rod-type photonic crystal fiber through the signal coupling lens, and pump light is coupled into the cladding of the rod fiber through the hollow pump coupling lens. The structure optimizes the coupling between the signal light and the core of the rod-type photonic crystal fiber, and the coupling between the pump light and the cladding of the rod fiber respectively by introducing the hollow pump coupling lens. The purpose of this is to fully optimize the rod-type photonic crystal fiber amplifier, improve the amplification efficiency and improve the efficiency of a manufacturing process.

A sub-nanosecond laser system is disclosed. The sub-nanosecond laser system may include: a pump laser source operable to generate a pump laser beam having a pump wavelength; a first pump beam splitter operable to receive the pump laser beam and split the pump laser beam into at least a first split pump laser beam and a second split pump laser beam; a passively Q-switched seed laser operable to receive the first split pump laser beam and generate a seed laser beam; and an amplifier assembly operable to receive the second split pump laser beam and the seed laser beam. The amplifier assembly may include one or more amplifiers arranged in series in a multi-stage configuration, arranged in a multi-pass configuration, or a combination thereof.

Photonic chip includes an external cavity (EC) optical circuit to provide wavelength-selective optical feedback to a length of active optical fiber. Light generated in the active optical fiber may be coupled from the EC circuit to a light processing circuit of the photonic chip, such as an optical modulator or an optical mixer. The EC circuits may include single-frequency and multi-frequency optical filters, which may include ring resonators, dual-ring resonators, and optical modulators to support multi-frequency lasers. The EC circuits may further include pump combiners and optical isolators.

A method of additive manufacture utilizing a uniform laser beam is disclosed. A seed laser projects a laser beam having a first laser beam shape. At least one pre-amplifier is positioned to receive the laser beam and amplify laser beam power. A homogenizer is positioned to receive the amplified laser beam from the at least one pre-amplifier and alter the first laser beam shape into a second laser beam shape. A main amplifier is positioned to receive the amplified laser beam having the second laser beam shape from the homogenizer and amplify laser beam power.

A pumping light source outputs pumping lights. A pumping light source outputs a pumping light. Optical multiplexers couple the pumping lights to a plurality of cores. The optical multiplexer couples the pumping light to the clad. A pumping light source drive unit drives a pumping light source. A pumping light source drive unit drives a pumping light source. A monitoring unit outputs a monitoring signal indicating a monitoring result of the number of wavelengths used in each of optical signals amplified by the plurality of the cores. The control unit controls the power of the pumping lights based on the monitoring signal. The control unit controls the power of each of the pumping lights in accordance with the number of wavelengths used in each of the optical signals and controls the power of the pumping light so that signal qualities of the optical signals fall within a prescribed range.

A laser ignition device includes a laser oscillation optical system that produces pulsed laser light, a condensing optical element that condenses the pulsed laser light into a combustion chamber, a housing that internally contains the condensing optical element, and an optical window that is provided distally with respect to the condensing optical element in the housing and transmits the pulsed laser light. The pulsed laser light is shaped as a ring around an optical axis at least at a light passage position in the optical window.

Aspects of the present application are related to an Er-doped waveguide amplifier (EDWA) structure integrated in an uncooled silicon photonic transceiver and methods for fabricating the same. In some embodiments, the structure comprises three layers of waveguides: silicon, silicon nitride and Er-doped dielectric. The three layers of waveguides are integrated with an uncooled 980-nm pump laser. In some embodiments, the Er-doped dielectric waveguides are fully etched.