Seiko Epson Corporation

Osamu Saito

Masahide Tsuda

Shigehiro Yanase

Kenichi Shioiri

Yasuaki Morita

Tetsuo Terashima

Takeshi Nakajima

A discharge lamp drive device includes a resonant circuit section connected to a discharge lamp, a power conversion section configured to convert direct-current power into alternating-current power, and supply the discharge lamp with the alternating-current power via the resonant circuit section, and a control section configured to supply the discharge lamp with the alternating-current power having a first frequency and a second frequency higher than the first frequency in a lighting start period until the discharge lamp reaches a steady lighting state, the first frequency is a frequency for causing a resonance of the resonant circuit section, and the second frequency is a quasi-resonant frequency.

Discharge lamp drive device, projector, and discharge lamp drive method

A discharge lamp lighting device according to an aspect of the invention includes a resonance circuit unit connected to a discharge lamp, a power converting unit configured to convert direct-current power into alternating-current power and supply the alternating-current power to the discharge lamp via the resonance circuit unit, and a control unit configured to supply the alternating-current power having a first frequency for causing resonance of the resonance circuit unit and a second frequency different from the first frequency, to the discharge lamp in a lighting start period from a start of lighting of the discharge lamp to a steady lighting state of the discharge. The second frequency is equal to or higher than 100 kHz.

Discharge lamp lighting device, discharge lamp lighting method, and projector

A discharge lamp lighting device includes a discharge lamp, a resonant circuit section, a power conversion section, and a control section. The resonant circuit section is connected to the discharge lamp. The power conversion section is adapted to convert direct-current power into alternating-current power and then supply the discharge lamp with the alternating-current power via the resonant circuit section. The control section is adapted to change a frequency of the alternating-current power alternatingly between a first frequency and a second frequency different from the first frequency in a lighting start period until the discharge lamp reaches a stationary lighting state. The control section is adapted to change the first frequency toward a frequency causing a resonance of the resonant circuit in a stepwise manner. The second frequency is lower than the first frequency.

Discharge lamp lighting device, discharge lamp lighting method, and projector device

A discharge lamp lighting device includes a resonant circuit section connected to a discharge lamp, a power conversion section adapted to convert direct-current power into alternating-current power, and then supply the discharge lamp with the alternating-current power via the resonant circuit section, and a control section adapted to change a frequency of the alternating-current power in a stepwise manner with a frequency, which is different from a frequency causing a resonance of the resonant circuit section, intervening between frequency values of the frequency changed in a lighting start period until the discharge lamp reaches a stationary lighting state.

A projector includes a light source that emits excitation light, a fluorescent body that converts the excitation light into fluorescence, a liquid crystal optical modulation device that modulates light output from the fluorescent body, an optical sensor that detects at least one of the excitation light passing through the fluorescent body and the fluorescence converted by the fluorescent body, and a control device that controls at least one of the light source and the liquid crystal optical modulation device based on a detection result of the optical sensor.

Projector having fluorescent body and associated sensor

A discharge lamp lighting device according to the invention can reliably light a discharge lamp, and at the same time, prevent output of unnecessary high-voltage pulses with a simple circuit configuration. The discharge lamp lighting device includes a capacitor charged with a current from a direct-current power supply, a transformer adapted to output a starting pulse between electrodes of the discharge lamp in accordance with a discharge current flowing from the capacitor, a discharge control circuit adapted to switch ON/OFF the discharge current from the capacitor to the transformer, and a timing generation section adapted to switch the discharge control circuit to ON after a voltage between both ends of the capacitor has reached a reference voltage. The timing generation section can operate in accordance with a plurality of reference voltages.

Discharge lamp lighting device, projector, and method of controlling projector

Projector having fluoroscent body and associated sensor

A light source control device is for controlling a solid-state light source array having a plurality of solid-state light sources connected in series to each other, and includes a detector (a current detection resistor, voltage detection resistors, and operational amplifiers) adapted to detect at least one of a voltage applied to the solid-state light source array and a current supplied to the solid-state light source array, and a control circuit adapted to determine whether or not discontinuity of at least one of the voltage and the current is present using a detection result of the detector, and change control of one of the current and electrical power performed on the solid-state light source array if it is determined that the discontinuity is present.

Light source control device and projector

A projection-type display device according to an embodiment of the invention modulates light emitted from a solid-state light source array and projects the modulated light on a screen. The projection-type display device includes a power source device that generates power used for driving the solid-state light source array using power supplied from a power source, an instant interruption detecting circuit that detects an instant interruption of the power source, and a control device that, in a case where the instant interruption of the power source is detected by the instant interruption detecting circuit, performs control of extinguishing the solid-state light source array during at least a part of an instant interruption period until recovery after the detection of the instant interruption of the power source.

Projection-type display device and method of controlling thereof

A lighting device which lights the discharge lamp, includes: a converting circuit which converts the direct current into an alternating current; a pulse generating circuit which generates a high voltage pulse; and a trigger circuit which causes the pulse generating circuit to generate the high voltage pulse, wherein the pulse generating circuit includes a primary winding and a secondary winding and generates the high voltage pulse by increasing a current input to the secondary winding based on a current input to the primary winding, and the trigger circuit includes a high pass filter; a first capacitor which stores and discharges charges input via the high pass filter; and a third switching element which outputs an output current from a second capacitor connected in parallel to the converting circuit to the primary winding if an output voltage from the first capacitor exceeds a threshold.

Lighting device, lighting control device, illumination device, and projector

A lighting device which supplies power to an electrode of a discharge lamp to turn on the discharge lamp, includes: a converting circuit which converts inputted direct current into alternating current; a pulse generating circuit which produces a high-voltage pulse from the alternating current received from the converting circuit and applies the high-voltage pulse to the electrode; and a trigger circuit which is disposed between the converting circuit and causes the pulse generating circuit to apply the high-voltage pulse to the electrode, wherein the trigger circuit allows the pulse generating circuit to apply the high-voltage pulse to the electrode in accordance with a drive frequency of the converting circuit.

Growing community of inventors

Matsumoto, Japan

Osamu Saito