Ushio Denki Kabushiki Kaisha

Ebara Corporation

Takanori Samejima

Hiroshi Ikeda

Masashi Okamoto

Yoshikazu Suzuki

Yoshihiro Horikawa

Yuichi Miura

Fumihiko Oda

Takashi Yamashita

Koji Yamada

Minoru Fukuda

Atsushi Imamura

Nobuhiko Sugihara

Kentaro Fujita

Kazuhiro Yoshida

Kensuke Nakamura

Kenji Kamimura

Akihiko Sugitani

Takashi Kyotani

Takahiro Hiraoka

Izumi Takaya

Mikio Shimizu

Takayuki Kozakura

Keiichi Matsumoto

Isao Miyake

Toru Nishikubo

Tetsuya Ozawa

Munetaka Kitajima

Shohei Tsukamoto

Hirotaka Yamada

The lighting circuit for lighting a dielectric barrier discharge lamp includes a direct-current power source, a transformer having a primary winding connected to a positive electrode-side terminal of the direct-current power source and a secondary winding connected to the dielectric barrier discharge lamp, a closed circuit in which the direct-current power source, the primary winding, and a switching element including a parasitic diode are serially connected, and a controller to perform ON/OFF control of the switching element. The controller executes a first step to shift the switching element from an ON state to an OFF state and a second step to shift the switching element from the OFF state to the ON state after a lapse of a predetermined OFF holding time from when a regenerative current flowing through the primary winding reaches a zero value after the first step.

Light source device, dielectric barrier discharge lamp lighting circuit, dielectric barrier discharge lamp lighting method

A dielectric barrier plasma generator includes: a dielectric substrate, a high-voltage electrode provided on a first surface of the dielectric substrate, a low-voltage electrode provided to face a second surface of the dielectric substrate, a power introduction section provided at a first end of the high-voltage electrode, a gas channel formed from a first end to a second end thereof between the dielectric substrate and the low-voltage electrode to allow gas to flow from the first end of the gas channel to the second end thereof, and a blowout outlet formed at the second end of the gas channel to blow out the gas that has flown through the gas channel and plasma that has been generated in the gas channel. The dielectric substrate includes a portion having a thickness being thinner when being closer to the blowout outlet.

Dielectric barrier plasma generator and plasma discharge starting method for dielectric barrier plasma generator

A light source unit includes: elemental light sources each including light emitting elements and drive circuits; an integrated control circuit that controls the drive circuits; and band optical characteristic acquisition sections that receive light of an amount correlated with a total light amount of output luminous fluxes to acquire light emitting intensity indicating values and wavelength deviation indicating values. The integrated control circuit at least intermittently acquires band optical characteristic acquisition data to generate the light emitting intensity indicating values and the wavelength deviation indicating values. The integrated control circuit holds light emitting intensity indicating value target variation information, and determines the variation of the light emitting intensity indicating values, in accordance with the light emitting intensity indicating value target variation information belonging to one appearance mode of the wavelength deviation indicating values assumed on a basis of an actual mode of the generated wavelength deviation indicating values.

Light source unit and projector

A light source unit including: a plurality of elemental light sources each including a light emitting element and a drive circuit; a control circuit configured to control the drive circuit; and a luminous flux characteristic measurement section configured to measure received output luminous fluxes to generate luminous flux chromaticity-intensity correlation data. The control circuit generates a single-color color-phase indicating value, based on the luminous flux chromaticity-intensity correlation data. The control circuit determines a ratio of intensity of additional light to intensity of main component light to allow the single-color color-phase indicating value to become equal to a target value thereof, and generates an integrated color-phase indicating value, based on the luminous flux chromaticity-intensity correlation data. The control circuit performs feedback control on the drive circuits to allow a difference between the integrated color-phase indicating value and a target value thereof to be small.

A light source unit includes: a plurality of elemental light sources; an optical sensor; a light quantity measurement circuit; and a control circuit. The plurality of elemental light sources each include one or more light emitting elements, one or more drive circuits, a focusing optical system, and an optical fiber. The one or more drive circuits selectively operate in a driving state or in a non-driving state. The control circuit performs a sequence that sequentially acquires light quantity measurement data by sequentially selecting one of the plurality of elemental light sources, putting at least one of the one or more drive circuits included in the selected elemental light source into a first state, and putting the plurality of drive circuits other than the at least one drive circuit into a second state, and detects abnormality based on a plurality of pieces of the acquired light quantity measurement data.

Projector light source unit having intensity controller

The purpose of the present invention is to make it possible to output stable light by optimizing the wavelength conversion efficiency in a wavelength conversion element without employing an optical detection device such as a photo diode in a laser light source device. A fundamental light wave emitted from a semiconductor laser () is wavelength converted by a wavelength conversion element () and is emitted therefrom. A lighting circuit () supplies electric power for the aforementioned semiconductor laser () to turn on the semiconductor laser (). A control unit () controls the operation of the device while controlling the amount of power supplied to a heater means () such that the wavelength conversion element () reaches a temperature at which optimum wavelength conversion efficiency is acquired. The temperature detected by a temperature detection means (Th) is input to the control unit (), and the control unit () defines the temperature of the wavelength conversion element () at which the maximum amount of power is supplied to the heater means () as a set temperature at which the optimum wavelength conversion efficiency is acquired, and performs feedback control of the temperature of the wavelength conversion element () so that the temperature of the wavelength conversion element () reaches the aforementioned set temperature by controlling the amount of heat supplied from the heater means ().

Laser light source apparatus and temperature control method of wavelength conversion element in laser light source apparatus

A light source unit includes: a plurality of elemental light sources each including one or more light emitting elements and one or more drive circuits; a control circuit; and a plurality of color band light characteristic measurement sections each configured to receive light to generate color band light characteristic measurement data. A plurality of the light emitting elements in the elemental light sources includes light emitting elements different in wavelength band of emission wavelength from one another. The color band light characteristic measurement sections are provided corresponding to a plurality of the wavelength bands. One or more of the color band light characteristic measurement sections include a first light intensity measurement section and a second light intensity measurement section. The control circuit generates light intensity indicating values and wavelength deviation indicating values, generates color phase indicating values, and performs first feedback control on the drive circuits.

A light source apparatus comprises a beam flux conversion optical system for making all the light emitting areas conjugate to one geometrical-optical output image, all the solid light emitting elements being in series connected to each other and fixed to a heat sink to be insulated to one another, circuits on the input and output sides of an electric supply circuit being not insulated, the electric supply circuit including an interface circuit for receiving a modulation amount specifying signal from a host circuit, wherein a ratio of ON time to a switching cycle of the switch element is controlled in a feedback manner so that a difference between current values indicated by the output current signal and a target current signal may become small, and the interface circuit generating analog quantity correlated to the amount of modulation specified by a modulation amount specifying signal through a data insulation transmission unit.

Light source apparatus and projector

To avoid accelerated progression of deterioration of a semiconductor laser, an LED, and the like to extend their lives while adjusting a balance of a plurality of colors, such as R, G, and B, by feedback control, a deterioration controllable monochromatic light source module is configured to: calculate a substantial upper limit Iu, determine an operation coefficient hx based on a deterioration coefficient dx, perform feedback control of the output current Ix of each drive circuit, and output a light intensity detection signal to the outside. An integrating control circuit calculates a monochromatic light intensity sum &#x3c3; by a sum of light intensity detection signals from the monochromatic light source modules belonging to the same wavelength band and determines a light intensity target signal so that a ratio of the monochromatic light intensity sum &#x3c3; to the monochromatic light source modules in different wavelength bands is a predetermined ratio.

Light source device and projector

The wavelength of fundamental wave light emitted from a semiconductor laser is converted by a wavelength conversion element, and the wavelength-converted light is emitted. A power supply circuit feeds electric power to the semiconductor laser. A control part controls an amount of electric power to be fed to a heater such that the wavelength conversion element becomes a temperature that optimizes the wavelength conversion efficiency. Temperatures detected by an element temperature detector and a light source part temperature detector are introduced to the control part, and the control part takes a wavelength conversion element temperature, at which a temperature detected by the light source part temperature detector is minimum, as a set temperature that makes the wavelength conversion efficiency optimal, and feedback-controls the wavelength conversion element temperature such that the wavelength conversion element temperature is at the set temperature by controlling the heating quantity of the heater.

Laser light source apparatus, and method for controlling temperature of wavelength conversion element in laser light source apparatus

A polarity-reversal control circuit gives a polarity-reversal order so that the polarity of an inverter is inverted each time the polarity-reversal timing notified by a signal is recognized. The number of times of consecutive appearances of a normal polarity-reversal interval period, in which an interval of adjoining polarity-reversal timings is equal to or less than an upper limit of a polarity-reversal interval desirable for a discharge lamp, is counted, and if the unusual polarity-reversal interval period, in which an interval of the adjoining polarity-reversal timing is longer than the upper limit of a polarity-reversal interval, appears, Npm is memorized as the maximum of the number of times of consecutive appearances and after that, when the polarity-reversals signal in which the number of times of consecutive appearances becomes equal to Npm is received, it is regarded as a start of an unusual polarity-reversal interval period, and additional polarity-reversal order is given.

Discharge lamp lighting apparatus and projector

The fundamental wave light emitted from a semiconductor laser is converted in wavelength by a wavelength conversion element and emitted therefrom. A lighting circuit lights the semiconductor laser, and a temperature control unitcontrols the amount of electric power supply to a heater so that the temperature of the wavelength conversion element turns into temperature at which the wavelength conversion efficiency thereof becomes optimal. When a state where the amount of electric power supply of the heater is lower limit or below continues for a predetermined period or longer, the hang-up suppressing unit, or when duration time in a state where the temperature of the wavelength conversion element is higher than the control target temperature becomes higher than a constant value, laser lighting current is decreased by a preset amount, thereby recovery from a high temperature hang-up state performed.

Laser light source apparatus

A discharge lamp lighting device having a discharge lamp which has a pair of tungsten-made electrodes each having a protrusion formed at the tip thereof and an electric power feeding device which feeds an alternate current electric power to the discharge lamp, and is characterized in that the power feeding device has a function of switching between a first lighting mode in which a rated electric power is fed to the discharge lamp and a second lighting mode in which a lower electric power than the rated electric power is fed to the discharge lamp to light the discharge lamp, and therefore, can control electric power to be fed to the discharge lamp under such conditions that the average electric power change rate becomes 0.01-2.1 W/s during a mode switching period in which the switching from the first lighting mode into the second lighting mode is carried out.

Discharge lamp lighting apparatus

To maintain the shape of the projection on the electrodes of the tip end for a long time to extend the lifetime of a discharge lamp, a lighting device lighting a high pressure discharge lamp supplies alternating current such that an alternating current with a basic frequency at the time of the steady state lighting selected from a range between 60 and 1000 Hz and a low frequency of a half cycle with a frequency lower than the basic frequency are generated alternatingly. The alternating current is supplied such that the waveform with one polarity of the low frequency appears consecutively at least twice. It is also possible for the alternately generated low frequency to be lower than the basic frequency in a range from 5 to 200 Hz, and for the interval during which the basic frequency is supplied to be gradually increased and decreased at specified times.

High pressure discharge lamp lighting device with electrode temperature control

In a lighting apparatus containing a high pressure discharge lamp, an alternating current supplied to the discharge lamp at the time of steady lighting of the frequency (basic frequency) selected from a range between 60 and 1000 Hz and a low frequency having a frequency selected from a range between 5 and 200 Hz lower than the basic frequency is generated alternately. The frequency of the low frequency wave is changed in response to the change of the lighting voltage of the discharge lamp. The supply period of the basic frequency is increased and decreased little by little by every predetermined time.

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Hyogo, Japan

Takanori Samejima