Canon Kabushiki Kaisha

Kyosan Electric Mfg. Co., Ltd.

Satoshi Aikawa

Itsuo Yuzurihara

Ryosuke Ohma

Yasuhiro Nakahara

Tomoyuki Iwanaga

Hiroshi Kunitama

Koji Uchida

Yasuhiro Dobashi

Hideyuki Ooban

Toshifumi Masaki

Yohei Saito

Hideyuki Ohban

Yoshitaka Nakano

Sadao Mori

Tadaharu Ohno

In the reactor in which the wiring board with the main winding formed thereon and the wiring board with the control winding formed thereon are incorporated in layers into the planer core, the magnetic flux generated by the main winding and the magnetic flux generated by the control winding are brought into the following states in order to equalize the density of the magnetic flux generated by the control current. A main winding current of high-frequency current flowing through the main winding generates an AC magnetic fluxes, each of the fluxes having a magnetic field in a direction opposite to each other so as to cancel each other out, and a control current of direct current flowing through the control winding generates a DC magnetic flux with a uniform magnetic flux density around the pair of the inner legs of which AC magnetic fluxes are cancelled out each other.

Reactor

An excessive voltage rise of load voltage, caused by an impedance mismatching on a transmission path, is prevented, and high-frequency power is regenerated. A parallel impedance is connected to the transmission path during the voltage rise, thereby regenerating voltage caused by a standing wave and preventing excessive load voltage, together with enhancing energy usage efficiency. Establishing the parallel impedance for the load impedance, on the transmission path between the high-frequency amplifier circuit of the high-frequency power supply device and the high-frequency load, reduces impedance at the connecting position to prevent generation of excessive voltage on the transmission path, and high-frequency power is regenerated from the transmission path by the parallel impedance.

Regeneration circulator, high-frequency power supply device, and high-frequency power regeneration method

An impedance matching device comprising a variable reactor having a main winding and control winding, wherein a generated magnet field in the core is an AC magnetic field with a magnitude exceeding a value to settle a deviation between a control target value for impedance matching and a feedback value, by changing the magnitude of the generated magnetic field by changing a control current passing through the control winding, thereby controlling inductance of the variable rector to be a predetermined value to perform impedance matching, the response delay in the impedance matching is reduced by reducing a response delay in the inductance variation of the variable reactor.

Impedance matching device

In detecting the unignited state of plasma based on a reflected wave, false detection during a normal plasma ignition time is prevented so as to detect the unignited state during plasma abnormality. When a pulse output is supplied to a plasma load by pulse driving from an RF power source, the unignited state of plasma abnormality is detected on the basis of the continuous state of the reflected wave, whereby a total reflected wave generated in the unignited state during plasma abnormality is detected in distinction from the reflected wave generated in the normal ignited state. With this configuration, in detecting the unignited state by comparing a peak value of the reflected wave with a threshold, it is possible to prevent that a reflected wave generated in the normal ignited state is erroneously detected as the total reflected wave that is generated in the abnormal unignited state.

Unignited plasma state discrimination device and unignited plasma state discrimination method

In a class-D amplifier, oscillation phenomenon is suppressed in a high RF range and surge voltage is reduced. An oscillation absorption circuit is connected on the power supply side of the class-D amplifier circuit, and the class-D amplifier circuit and thus connected oscillation absorption circuit equivalently configure an oscillation circuit. Resistance provided in the oscillation absorption circuit is assumed as damping resistance of the oscillation circuit, thereby suppressing the oscillation phenomenon and reducing the surge voltage. The oscillation absorption circuit is made up of the RL parallel circuit of resistance and inductance. The oscillation absorption circuit and the class-D amplifier circuit constitute the oscillation circuit, and the resistance of the oscillation absorption circuit constitutes the damping resistance of the oscillation circuit in the high RF range.

Class-D amplifier

A high-frequency power supply device is provided with a plasma ignition step that supplies pulse power to ignite plasma, and drive power supply step to supply drive power for maintaining the plasma being generated. In the plasma ignition step, an ignition pulse being applied in an ignition pulse output operation is configured as including a main pulse that induces ignition, and a prepulse with lower power than the power of the main pulse and being applied at a stage prior to the main pulse. Since the ignition pulse is configured as including the main pulse and the prepulse, this enables protection of a high-frequency power source against reflected wave power, as well as reliably igniting the plasma.

High-frequency power supply device, and plasma ignition method

When RF power is supplied from an RF generator to a load via a power supply unit,

High-frequency power supply device and ignition voltage selection method

In an RF power supply for supplying RF power to a plasma load, reflected wave power control is performed in which the reflected wave power of an RF generator is detected and the RF generator is controlled. For a short-time variation in reflected wave power, control is performed based on a peak value variation in the detection value of reflected wave power. For a long-time variation in reflected wave power, control is performed based on a variation in a smoothed value obtained by smoothing detection values of reflected wave power. A reflected wave power control loop system includes a reflected wave power peak value dropping loop system and an arc blocking system that perform control based on a peak variation in reflected wave power and a reflected wave power amount dropping loop system that performs control based on a smoothed power amount of reflected wave power.

High-frequency power supply device and reflected wave power control method

An ophthalmic apparatus including an operation stick to adjust an optical unit, comprising: a rotary dial that is provided on a side surface of the operation stick and rotates with respect to the operation stick; a trigger arranged on a top of the operation stick while being decentered with respect to the operation stick; and a control unit adapted to control to perform one of movement and focusing of the optical unit with respect to an object in accordance with rotation of the rotary dial and perform control to cause the optical unit to start a predetermined operation in accordance with press of the trigger.

Ophthalmic apparatus

A fundus imaging apparatus selects a focal position detection method in accordance with whether a diopter correction lens is inserted in an optical path of an imaging optical system that includes an imaging unit; and detects a focal position based on a signal from the imaging unit according to the selected focal position detection method.

Fundus imaging apparatus and control method

An ophthalmologic apparatus including an index projection unit to project an index on a cornea of a subject's eye, an imaging unit to form an image on an imaging plane via an objective lens and capture an image of the index projected on the cornea, and a control unit to control a distance between the subject's eye and the object lens so that a size of the captured index becomes a predetermined size.

Fundus camera

A fundus capturing apparatus, comprising: an irradiation unit adapted to irradiate light through an illumination light path onto a fundus of an eye to be examined; a capturing unit adapted to capture a fundus of the eye to be examined with reflection light of the light irradiated by the irradiation unit; a focus confirming unit adapted to confirm a focus state of the fundus captured by the capturing unit, the focus confirming unit being arranged on the illumination light path; a moving unit adapted to move the focus confirming unit on the illumination light path along a guide axis that is parallel to the illumination light path, in accordance with the focus state; and an advancing/retracting unit adapted to insert the focus confirming unit into the illumination light path or retract the focus confirming unit from the illumination light path by rotating it with respect to the guide axis.

Fundus capturing apparatus

When an observation state by an infrared LEDis changed to a photographing state by a xenon lamp, a movable mirroris pulled upward and an optical path is switched to an image sensorside. A light guideis shifted by an alignment index drive motorso that an incident portion of an alignment index is shifted from a visible LEDto direct to an infrared LED. An outgoing portion of the light guideis set at a position where an image is formed on the image sensorby a wavelength of the infrared LEDwhen an operation distance is appropriate. While changing a luminescent color, a position of a luminescent point of the alignment index is changed by switching the LED by the shift of the light guide

Ophthalmologic photographing apparatus

A fundus imaging apparatus comprises: a plurality of light source modules with different wavelengths; a moving unit adapted to move one of the plurality of light source modules to a position to illuminate a fundus of an eye to be examined through an illumination optical system, based on a selected imaging mode; and an image sensor which captures feedback light from the fundus of the eye illuminated through the illumination optical system.

Growing community of inventors

Yokohama, Japan

Satoshi Aikawa