A radiation source apparatus comprising: a container (400) for being pressurized with a gaseous medium in which plasma which emits plasma emitted radiation is generated following excitation of the gaseous medium by a driving radiation (50), wherein said container is operable (66, 67) substantially to remove radiation with a wavelength of 10-400 nm from said plasma emitted radiation before said plasma emitted radiation exits said container as output radiation. In an embodiment the container comprises: an inlet radiation transmitting element (64) operable to transmit said driving radiation from outside said container to inside said container, and an outlet radiation transmitting element (65) operable to transmit at least some of said plasma emitted radiation from inside said container to outside said container as output radiation; wherein at least one of said inlet and outlet radiation transmitting elements comprises a plane parallel plate.

A radiation source apparatus comprising: a container (400) for being pressurized with a gaseous medium in which plasma which emits plasma emitted radiation is generated following excitation of the gaseous medium by a driving radiation (50), wherein said container is operable (66, 67) substantially to remove radiation with a wavelength of 10-400 nm from said plasma emitted radiation before said plasma emitted radiation exits said container as output radiation. In an embodiment the container comprises: an inlet radiation transmitting element (64) operable to transmit said driving radiation from outside said container to inside said container, and an outlet radiation transmitting element (65) operable to transmit at least some of said plasma emitted radiation from inside said container to outside said container as output radiation; wherein at least one of said inlet and outlet radiation transmitting elements comprises a plane parallel plate.

A system for controlling convective flow in a light-sustained plasma includes an illumination source configured to generate illumination, a bulb-less gas containment structure, and a collector element arranged to focus illumination from the illumination source into the volume of gas in order to generate a plasma within the volume of gas contained within the bulb-less gas containment structure. Further, the plasma is generated within a concave region of the collector element, where the collector element includes an opening through the collector element for propagating a portion of a plume of the plasma from a first region of the bulb-less gas containment structure to a second region of the bulb-less gas containment structure, wherein the first region of the bulb-less gas containment structure and the second region of the bulb-less gas containment structure are at least partially separated by a surface of the collector element.

A system for controlling convective flow in a light-sustained plasma includes an illumination source configured to generate illumination, a bulb-less gas containment structure, and a collector element arranged to focus illumination from the illumination source into the volume of gas in order to generate a plasma within the volume of gas contained within the bulb-less gas containment structure. Further, the plasma is generated within a concave region of the collector element, where the collector element includes an opening through the collector element for propagating a portion of a plume of the plasma from a first region of the bulb-less gas containment structure to a second region of the bulb-less gas containment structure, wherein the first region of the bulb-less gas containment structure and the second region of the bulb-less gas containment structure are at least partially separated by a surface of the collector element.

An electrodeless laser-driven light source includes a laser that generates a CW sustaining light. A pump laser generates pump light. A Q-switched laser crystal receives the pump light generated by the pump laser and generates pulsed laser light at an output in response to the generated pump light. A first optical element projects the pulsed laser light along a first axis to a breakdown region in a gas-filled bulb comprising an ionizing gas. A second optical element projects the CW sustaining light along a second axis to a CW plasma region in the gas-filled bulb comprising the ionizing gas. A detector detects plasma light generated by a CW plasma and generates a detection signal at an output. 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 that generates a CW sustaining light. A pump laser generates pump light. A Q-switched laser crystal receives the pump light generated by the pump laser and generates pulsed laser light at an output in response to the generated pump light. A first optical element projects the pulsed laser light along a first axis to a breakdown region in a gas-filled bulb comprising an ionizing gas. A second optical element projects the CW sustaining light along a second axis to a CW plasma region in the gas-filled bulb comprising the ionizing gas. A detector detects plasma light generated by a CW plasma and generates a detection signal at an output. 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.

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.

The object of this invention is to provide a gas discharge device which has a simple configuration, inexpensive, and has excellent luminous efficiency, for an ultraviolet or visible light source.

The invention provides a gas discharge device in which first and second long electrodes extending toward either side along a longitudinal direction with a discharge gap interposed therebetween are provided outside of a back side flat surface of a thin glass tube, the thin glass tube filled with a discharge gas having a front side flat surface and the back side flat surface facing each other on a transverse section, wherein, starting with trigger discharge that is initially generated in the discharge gap as a result of a voltage increase when a voltage with a sine waveform or an inclined waveform is applied between both electrodes, the discharge gradually extends so as to move in the longitudinal direction of the electrodes. Ultraviolet light having high luminous efficiency and emission intensity is obtained from the flat surface at the front surface side by forming an ultraviolet phosphor layer in the thin glass tube and driving the device with a sine-wave voltage.

The object of this invention is to provide a gas discharge device which has a simple configuration, inexpensive, and has excellent luminous efficiency, for an ultraviolet or visible light source.

The invention provides a gas discharge device in which first and second long electrodes extending toward either side along a longitudinal direction with a discharge gap interposed therebetween are provided outside of a back side flat surface of a thin glass tube, the thin glass tube filled with a discharge gas having a front side flat surface and the back side flat surface facing each other on a transverse section, wherein, starting with trigger discharge that is initially generated in the discharge gap as a result of a voltage increase when a voltage with a sine waveform or an inclined waveform is applied between both electrodes, the discharge gradually extends so as to move in the longitudinal direction of the electrodes. Ultraviolet light having high luminous efficiency and emission intensity is obtained from the flat surface at the front surface side by forming an ultraviolet phosphor layer in the thin glass tube and driving the device with a sine-wave voltage.