There is provided a passive Q-switch pulse laser device including a laser medium, and a saturable absorber. The laser medium is disposed between a pair of reflection means included in an optical resonator. The laser medium is excited by specific excitation light to emit emission light. The saturable absorber is disposed on an optical axis of the optical resonator and on a downstream side of the laser medium between the pair of reflection means. The saturable absorber has a transmittance increased by absorption of the emission light. At least one of the pair of reflection means is a polarizing element. The polarizing element has different reflectances with respect to the respective pieces of emission light in polarization directions orthogonal to each other.

A laser ignition device includes an excitation light source that generates excitation light, and a pulsed laser oscillator connected to the excitation light source, wherein the pulsed laser oscillator generates a plurality of pulsed light beams at a time of one ignition to produce an initial flame.

An electrodeless laser-driven light source includes a laser source that generates CW sustaining light. A pump laser generates pump light. A Q-switched laser crystal is positioned to receive the pump light and generates pulsed laser light in response to the generated pump light that propagates to a breakdown region in a gas filled bulb comprising an ionizing gas. A detector detects plasma light generated by a CW plasma located at least partly in a CW plasma region in the gas filled bulb comprising the ionizing gas and generates a detection signal. A controller generates control signals that control the pump light to the Q-switched laser crystal so as to extinguish the pulsed laser light within a time delay after the detection signal exceeds a threshold level.

An electrodeless laser-driven light source includes a laser source that generates a CW sustaining light and a pump laser that generates a pump. An optical beam combiner combines the CW sustaining light and the pump such that the CW sustaining light and the pump propagate co-linearly. A Q-switched laser crystal generates pulsed light in response to the pump. A gas-filled bulb is configured such that the pulsed light ignites a pulse plasma in a breakdown region of the gas bulb and the sustaining light sustains a CW plasma in a CW plasma region of the gas bulb, thereby emitting a high brightness light from the gas bulb, where the gas-filled bulb is positioned between the output of the pump laser and the pump input of the Q-switched laser crystal such that the CW plasma absorbs the pump light quenching the pulsed light generated by the Q-switched laser crystal.

Dermatological systems and methods for providing a picosecond laser treatment a plurality of treatment wavelengths, at least one of which is provide by an optical parametric oscillator (OPO) capable of providing picosecond laser pulses at a wavelength in the red region of the visible electromagnetic spectrum for treating one or more target tissue types. In some embodiments, the OPO is capable of providing picosecond laser pulses at a wavelength in one of the near-infrared and the infrared region of the electromagnetic spectrum.

The invention discloses a visible laser apparatus including a linear cavity. The linear cavity includes along the first direction: a first optical component, a gain medium, a second optical component, a Raman crystal, a double-harmonic crystal and a third optical component. The first optical component receives an incident pumping light in the first direction. The gain medium receives the pumping light from the first optical component, and generates a first infrared base laser having a first wavelength. The second optical component has a first high transmittance in a first wave band including the first wavelength in the first and the second directions. The Raman crystal receives the first infrared base laser, and generates a second infrared base laser having a second wavelength. The double-harmonic crystal receives the first and the second infrared base lasers, and generates a visible laser light having a third wavelength.

In a general aspect, a system for generating radio frequency (RF) electromagnetic radiation includes a maser having a photonic crystal structure and a vapor. The photonic crystal structure is formed of dielectric material and includes an array of cavities having a defect region disposed therein and an elongated slot disposed in the defect region. The array of cavities and the elongated slot define a waveguide having a waveguide mode. The vapor is disposed in the elongated slot and includes one or more input electronic transitions and an output electronic transition coupled to the one or more input electronic transitions. The output electronic transition is operable to emit a target RF electromagnetic radiation and is resonant with the waveguide mode. The system also includes a laser system configured to provide input optical signals to the elongated slot and signal processing electronics in communication with the laser system.

In a general aspect, a photonic crystal maser includes a dielectric body having an array of cavities ordered periodically to define a photonic crystal structure in the dielectric body. The dielectric body also includes a region in the array of cavities defining a defect in the photonic crystal structure. An elongated slot through the region extends from a slot opening in a surface of the dielectric body at least partially through the dielectric body. The array of cavities and the elongated slot define a waveguide having a waveguide mode. The photonic crystal maser also includes a vapor or source of the vapor in the elongated slot and a laser configured to generate an optical signal capable of exciting one or more input electronic transitions of the vapor.

The present invention relates to a solid-state blended polymer system that has the property of tunable lasing wavelength through adjusting the blending ratio. It can be used for health monitoring, environmental monitoring sensor and tissue imaging. Current materials do not have the broad tunable range; from blue to infra-red across the optical range. By using the same two polymers, it is possible to produce laser emitting blue to red colour. It simplifies the design, eases multi-wavelength laser sensor system integration and therefore, making the production cost-effective.

A device includes an active laser medium operative to emit spatially coherent light of a predetermined wavelength along an optical axis, first and second mirrors aligned with the optical axis and defining a resonant cavity enclosing the active laser medium, and a modulator including an organic solid crystal disposed along the optical axis between the first and second mirrors and configured to change a polarization state of the emitted light.