Abstract: According to the present invention there is provided a laser apparatus capable of efficient oscillation with an excitation power source with comparatively low frequency, wherein discharge is obliquely generated within the rectangular section of a discharge space. There is also provided a laser apparatus with a pair of preliminary discharge excitation electrodes which can readily initiate discharge. There is further provided a laser apparatus capable of efficient oscillation with an excitation power source with comparatively low frequency, wherein provided is a pair of discharge excitation electrodes located in the major side direction of discharge space whose length is more than three times as long as that of minor side direction thereof. There is further provided a laser apparatus with a pair of discharge excitation electrodes whose dimension is smaller than that of a pair of dielectric plates, which apparatus can prevent undesirable discharge.

Abstract: A laser apparatus includes an unstable resonator having a total reflection mirror and a take-out mirror, and further includes shading means for shading a disturbed phase portion of a laser beam so as to derive exclusively a light having a uniform phase by shading the disturbed phase portion of the beam emitted from the resonator or the beam in the resonator.

Abstract: According to the present invention there is provided a laser apparatus capable of efficient oscillation with an excitation power source with comparatively low frequency, wherein discharge is obliquely generated within the rectangular section of a discharge space. There is also provided a laser apparatus with a pair of preliminary discharge excitation electrodes which can readily initiate discharge. There is further provided a laser apparatus capable of efficient oscillation with an excitation power source with comparatively low frequency, wherein provided is a pair of discharge excitation electrodes located in the major side direction of discharge space whose length is more than three times as long as that of minor side direction thereof. There is further provided a laser apparatus with a pair of discharge excitation electrodes whose dimension is smaller than that of a pair of dielectric plates, which apparatus can prevent undesirable discharge.

Abstract: A microwave plasma apparatus comprises a discharge chamber for generating a plasma. A dielectric plate is placed on a surface of the discharge chamber. A microwave circuit surrounds the longitudinal side surface of the dielectric plate and the microwave circuit is adapted to couple the signal propagating therein to the dielectric plate, whereby a microwave electric field is formed within the discharge chamber to generate a plasma therein. The microwave circuit may comprise a rectangular waveguide, and a part of a wall surface of the rectangular waveguide is utilized as a terminal portion.

Abstract: A microwave discharge light source device in which one side of a discharge space in which a plasma emission takes place is defined by a transparent dielectric member. A transparent microwave reflecting member is disposed in a position such as to face the discharge space through the dielectric member. A microwave having an electric field component in the direction of thickness of the dielectric member is introduced into the dielectric member through the coupling at an end surface of the dielectric member so that a microwave electric field is formed in the discharge space, and so that the plasma emission medium emits light by electric discharge. The light thus emitted is extracted through the transparent microwave reflecting member.

Abstract: A power supply circuit for a magnetron adapted to supply microwave energy to an electrodeless discharge bulb is disclosed. The circuit includes a rectifier coupled across a commerical AC voltage source, a filter for smoothing the output of the rectifier, an inverter for converting the DC voltage supplied from the filter into a high frequency AC voltage, a step-up transformer for stepping up the high frequency AC voltage outputted from the inverter, and a rectifier which rectifies the high voltage AC output of the transformer into a unidirectional voltage which is supplied to the magnetron. The inverter switching is controlled by a pulse width modulation control circuit to maintain the magnetron output power at a predetermined level.

Abstract: A power supply circuit for a magnetron adapted to supply microwave energy to an electrodeless discharge bulb is disclosed. The circuit includes a rectifier coupled across a commercial AC voltage source, a filter for smoothing the output of the rectifier, an inverter for converting the DC voltage supplied from the filter into a high frequency AC voltage, a step-up transformer for stepping up the high frequency AC voltage outputted from the inverter, and a rectifier which rectifies the high voltage AC output of the transformer into a unidirectional voltage which is supplied to the magnetron. The inverter switching is controlled by a pulse width modulation control circuit to maintain the magnetron output power at a predetermined level.

Abstract: A gas laser device comprises a discharge space in which a laser gas is excited by electric discharge, the discharge space being in the form of a slab whose section perpendicular to a laser optical axis has a longer side and a shorter side; and laser resonator mirrors disposed at both ends of the discharge space, respectively. The laser resonant mirrors constitute a negative branch unstable resonator in a first dimension of longer side of the discharge space section, and a laser beam is obtained at one end of the longer side of the discharge space section.

Abstract: An apparatus for forming a thin film on a substrate by bringing a first gas and a second gas into reaction with each other in a reaction chamber near the surface of the substrate in the reaction chamber. The apparatus has a plasma generating chamber disposed adjacent to the reaction chamber for generating a plasma of the first gas in a predetermined direction. A first gas inlet is provided at the boundary between the plasma generating chamber and the reaction chamber and formed to extend in the predetermined direction, while a second gas inlet is provided in the vicinity of the first gas inlet and extended in the predetermined direction.

Abstract: A power supply circuit for a magnetron adapted to supply microwave energy to an electrodeless discharge bulb is disclosed. The circuit comprises a rectifier coupled across a commercial AC voltage source, a filter for smoothing the output of the rectifier, an inverter for converting the DC voltage supplied from the filter into a high frequency AC voltage, a step-up transformer for stepping up the high frequency AC voltage outputted from the inverter, and a rectifier which rectifies the high voltage AC output of the transformer into a unidirectional voltage which is supplied to the magnetron. The inverter switching is controlled by a pulse width modulation control circuit to maintain the magnetron output power at a predetermined level.

Abstract: The invention relates to a plasma apparatus where plasma is generated utilizing microwave discharge and laser excitation is performed and plasma processing is performed. More specifically, in a plasma apparatus where a microwave from a microwave oscillator is transmitted through a microwave transmission path to a microwave circuit, and plasma is generated by a microwave discharge within the microwave circuit, a plasma generating medium for generating the plasma is filled in a space formed between a conductor wall constituting a part of the microwave circuit and a dielectric installed opposite to the conductor wall, and the microwave circuit forms microwave mode having an electric field component orthogonal to the boundary between the dielectric and the plasma.

Abstract: In a microwave discharge light source apparatus for effecting discharge of an electrodeless discharge lamp held in a cavity which causes resonance by microwaves, the wall surface of the cavity resonator is constituted by a mesh and wires constituting the mesh, are electrically connected at each crossing point without resistance of contact. Effective discharging of the lamp is attainable and the cavity has a mechanically strengthened structure.

Abstract: An automatic tracking welding machine includes a pair of rotatably mounted sensors 6a, 6b disposed in advance of a welding torch 3 and coaxial therewith for detecting magnetic leakage flux across a weld line gap 10. The sensors are driven to equalize their outputs by a reversible stepping motor 15 supplied with drive pulses whose frequency is proportional to the sensor output difference up to a fixed limit, thereby implementing slowdown as the center or zero differential point is approached. Alternatively, a greater number of fixed sensors may be peripherally spaced around the torch housing and their outputs sequentially scanned and peak detected to track the weld line gap. In another embodiment a spaced pair of sensors 116a, 116b is laterally and bidirectionally driven by a reversible d.c. motor 123 supplied with a voltage proportional to the off-center distance detected by the sensors, thus also implementing slowdown as the zero point approaches.

Abstract: A microwave generated plasma light source including a microwave generator, a microwave cavity having a light reflecting member forming at least a portion of the cavity, and a member transparent to light and opaque to microwaves disposed across an opening of the cavity opposite the feeding opening through which the microwave generator is coupled. An electrodeless discharge bulb is disposed at a position in the cavity such that the cavity operates as a resonant cavity at least when the bulb is emitting light. In the bulb is encapsulated at least one discharge light emissive substance. The bulb has a shape and is sufficiently small that the bulb acts substantially as a point light source.

Abstract: A microwave generated plasma light source including a microwave generator, a microwave cavity having a light reflecting member forming at least a portion of the cavity, and a member transparent to light and opaque to microwaves disposed across an opening of the cavity opposite the feeding opening through which the microwave generator is coupled. An electrodeless discharge bulb is disposed at a position in the cavity such that the cavity operates as a resonant cavity at least when the bulb is emitting light. In the bulb is encapsulated at least one discharge light emissive substance. The bulb has a shape and is sufficiently small that the bulb acts substantially as a point light source.