Seiko Epson Corporation

Satoshi Kito

Junichi Suzuki

Shun Sato

Norio Imaoka

Tsuyoshi Kaneko

Tetsuo Hiramatsu

Kimio Nagasaka

Akira Miyamae

Hironori Hasei

Satoshi Fujii

Osamu Arakawa

A light source apparatus according to an aspect of the present disclosure includes an excitation light source that outputs excitation light, a ceramic phosphor that has a first surface and a second surface, converts in terms of wavelength part of the excitation light outputted from the excitation light source and incident via the first surface to generate fluorescence, and causes the fluorescence to exit via the second surface, and a substrate that supports the first surface of the ceramic phosphor. The excitation light outputted from the excitation light source is incident on an exposed portion of the first surface of the ceramic phosphor that is the portion exposed via the substrate. The distance in the exposed portion from an irradiated region irradiated with the excitation light to the substrate is 0.34 mm or greater.

Light source apparatus and projector

A ceramic composite according to the present disclosure has a phosphor phase containing an activator and a phosphor and a matrix phase containing MgO as a light transmissive ceramic material. The ceramic composite is made of an inorganic material, and the content of the phosphor phase is so set that the volume ratio of the phosphor phase to the entire phase including the matrix phase and the phosphor phase is lower than or equal to 20 vol %.

Ceramic composite, light source apparatus, and projector

A wavelength conversion element includes a substrate having a first surface, a first phosphor layer that has a first excitation light incident surface on which excitation light having a first wavelength is incident, is so provided as to face the first surface, a second phosphor layer that is so provided as to be in contact with part of the first excitation light incident surface, and a reflection layer that is provided between the first phosphor layer and the substrate. The first phosphor layer has an annular shape. The area of the second phosphor layer viewed in the direction in which the excitation light is incident is smaller than the area of the first phosphor layer viewed in the direction in which the excitation light is incident. The thickness of the second phosphor layer is smaller than the thickness of the first phosphor layer.

Wavelength conversion element, wavelength converter, light source apparatus, and projector

A light source apparatus according to an aspect of the invention includes an excitation light source that emits excitation light, a wavelength conversion layer on which the excitation light is incident and which converts the wavelength of the excitation light to emit fluorescence, a plurality of traveling direction changers that are formed in the wavelength conversion layer and change the traveling direction of the fluorescence, and a substrate on which the wavelength conversion layer is provided. The substrate is rotated around an axis of rotation to change the position on which the excitation light is incident on the wavelength conversion layer over time, and the interval between the plurality of traveling direction changers is smaller than the size of the region on which the excitation light is incident.

A discharge lamp driver includes a discharge lamp drive unit, a control unit, and a voltage detection part. When an inter-electrode voltage is smaller than a first predetermined value, the control unit controls the discharge lamp drive unit to provide a mixed period in which a first period and a second period are alternately repeated and a third period alternately including a first direct-current period and a second direct-current period. A length of the first direct-current period is larger than a length of the second direct-current period. The length of the second direct-current period is smaller than 0.5 ms. A total of the lengths of the first direct-current periods in the third period is larger than a length of the second period. When the inter-electrode voltage is smaller than the first predetermined value, the control unit is configured to increase the length of the third period in a stepwise manner.

Discharge lamp driver, light source, projector, and method of driving discharge lamp

A projector according to an aspect of the invention includes a discharge lamp having a light emitting tube and configured to emit light, a light modulation device configured to modulate the light emitted from the discharge lamp in accordance with an image signal, a projection optical system configured to project the light modulated by the light modulation device, a first detection section configured to detect ultraviolet light out of the light emitted from the discharge lamp, and a control section configured to determine a deterioration state of the light emitting tube based on a light intensity of the ultraviolet light detected by the first detection section.

Projector and method of controlling projector

In a discharge lamp driving device, a mixed period is provided, in which a first period in which an alternating current is supplied and a second period in which a direct current is supplied are alternately repeated and a third period alternately including a first direct current period and a second direct current period in which a direct current having a polarity opposite to a polarity of the direct current in the first direct current period is supplied. Length of the second direct current period is smaller than 0.5 ms. A total of lengths of the first direct current periods in the third period is larger than length of the second period. The third period is not provided at least when the inter-electrode voltage is smaller than a first predetermined value or when a cumulative lighting time of the discharge lamp is smaller than a second predetermined value.

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

A discharge lamp driving device according to one aspect of the invention includes a discharge lamp driving section configured to supply a driving current to a discharge lamp including electrodes and a control section configured to control the discharge lamp driving section. The control section controls the discharge lamp driving section such that a mixed period is provided in which a first period in which an alternating current having a first frequency is supplied to the discharge lamp and a second period in which a direct current is supplied to the discharge lamp are alternately repeated. The first frequency includes a plurality of frequencies different from one another. The control section temporally changes the length of the first period.

A discharge lamp driving device includes a discharge lamp driving unit configured to supply a driving current to a discharge lamp including electrodes, a controller configured to control the discharge lamp driving unit, and a voltage detection unit configured to detect an inter-electrode voltage of the discharge lamp, in which the controller controls the discharge lamp driving unit so that the driving current includes a hybrid period in which a first period for supplying an AC current with a first frequency to the discharge lamp and a second period for supplying a DC current to the discharge lamp are alternately repeated, in which the first frequency includes a plurality of different frequencies, and in which the controller changes the first frequency on the basis of at least one of the detected inter-electrode voltage and driving power supplied to the discharge lamp.

In at least one embodiment, a light source apparatus includes a discharge lamp with a pair of electrodes and a driving unit that supplies a driving current to the pair of electrodes. The driving unit includes an AC supplier that supplies an alternating current to the pair of electrodes and a DC supplier that supplies a direct current to the pair of electrodes. The AC supplier is configured to alternately repeat an AC supply section in which the alternating current is supplied and an AC stop section in which the supply of the alternating current is stopped. The DC supplier is configured to supply the direct current during a period corresponding to the AC stop section. A frequency of the direct current is not lower than 10 Hz and not higher than 1 kHz.

Light source apparatus, discharge lamp driving method, and projector

A discharge lamp driving device includes a discharge lamp driving section configured to supply a driving current to a discharge lamp, the driving current being an alternating current for driving the discharge lamp, and a control section configured to control the discharge lamp driving section. The control section controls the discharge lamp driving section such that the driving current having a driving frequency different from a natural frequency of the discharge lamp and a frequency of 1/2n (n is a natural number) times the natural frequency is supplied to the discharge lamp.

A light source apparatus includes a discharge lamp including a light-emitting container having a cavity in which a discharge medium is enclosed, and a pair of electrodes disposed such that respective tip portions thereof oppose each other in the cavity, and a driving unit that supplies a driving current to the pair of electrodes. The driving current is generated by modulating amplitude of alternating current having a frequency not lower than 1 kHz and not higher than 10 GHz, such that a first section and a second section in which the amplitude is smaller than in the first section are alternately repeated.

A light source device includes a discharge lamp including a pair of electrodes arranged to be opposed to each other in a hollow section in which a discharge medium is encapsulated and a driving device. The driving device includes a supplying unit configured to supply an alternating current having a frequency higher than 1 kHz to the pair of electrodes in a high-frequency period and a control unit configured to set at least a first frequency higher than 1 kHz and a second frequency higher than 1 kHz and different from the first frequency as the frequency of the alternating current, switch an alternating current having the first frequency and an alternating current having the second frequency in the high-frequency period, and control the supplying unit to repeat the high-frequency period to supply an alternating current to the pair of electrodes.

Driving device and driving method for discharge lamp, light source device, and projector

A light source device includes a discharge lamp, and a discharge lamp driving device that supplies a driving current to a pair of electrodes. The discharge lamp driving device includes an alternating current supply unit that supplies an alternating current with a frequency equal to or higher than 1 kHz and equal to or lower than 10 GHz to the electrodes, and a direct current supply unit that supplies a direct current to the electrodes.

Light source device, method of driving discharge lamp, and projector

A light source device includes a discharge lamp that has a first electrode and a second electrode opposed to each other in a hollow portion in which a discharge medium is enclosed and a driving device that supplies a driving voltage to the first electrode and the second electrode. The driving voltage is applied to the discharge medium through the first electrode and the second electrode such that the discharge medium emits light.

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Chino, Japan

Satoshi Kito