A light source system (200), comprises: a light-emitting device (1) for emitting a first light and a second light in sequence; a beam splitting system (2) with which the first light emitted from the light-emitting device (1) is divided into one beam in a first range of wavelength and the other beam in a second range of wavelength, respectively emitted along a first optical path and a second optical path, and also with which at least a part of the second light emitted from the light-emitting device (1) is emitted along the first optical path; a first spatial light modulator (211) for modulating the beam emitted from the beam splitting system (2) along the first optical path; a second spatial light modulator (213) for modulating the beam emitted from the beam splitting system (2) along the second optical path. The light source system (200) has the advantages of high light-emitting efficiency and low cost. A projection system comprising the aforementioned light source system (200) is also provided.

A wavelength conversion device according to an aspect of the invention includes a rotary device having a rotary part rotating around an axis, a base member rotated around the axis by the rotary device, an inorganic wavelength conversion element provided to the base member, and a heat radiation member fixed to the base member, the heat radiation member has a ring-like shape surrounding the axis, and spreads outward in a radial direction of the axis beyond the base member, and the heat radiation member and the base member are formed separately from each other.

A light source apparatus includes: a phosphor wheel that is provided with a plurality of ring-shaped light-emitting regions that are arranged concentrically and that respectively generate illumination light beams of a plurality of colors when irradiated by excitation light; a light source unit that simultaneously radiates the excitation light to the ring-shaped light-emitting regions; and a plurality of optical elements that are irradiated by the plurality of illumination light beams that are generated due to the irradiation of the excitation light.

The invention relates to a wavelength conversion element including: a substrate including a light-reflecting surface and rotatable around an axis of rotation; and a wavelength conversion layer supported by the light-reflecting surface. The wavelength conversion layer has a distribution of reflectance, along a circle centered on the axis of rotation, with respect to excitation light to excite the wavelength conversion layer. An average reflectance of the wavelength conversion layer with respect to the excitation light per the circle varies depending on a radius of the circle.

Provided is a fluorescent wheel for a projector capable of suppressing the heating of the phosphor layer and a light emitting device for a projector using the same. The fluorescent wheel for a projector includes: a phosphor layer (12); an annular ceramic substrate (11) which includes a first principal surface provided with the phosphor layer (12) and a second principal surface located on an opposite side to the first principal surface and has a higher thermal conductivity than the phosphor layer (12); and a reflective layer (13) provided on the second principal surface of the ceramic substrate (11).

An image projector includes: a light source to emit light; an image forming element irradiated with the light from the light source and to form an image for projection onto a projection surface; a first controller activated when the image projector is in a waiting state; and a second controller that is not activated when the image projector is in the waiting state. In response to detection of an execution request for executing the image projector in the waiting state at the first controller, the first controller sets a power supply circuit with an initial voltage to start supplying power to the light source, and when the light source is lighted at the initial voltage, activates the second controller.

A phosphor device of an illumination system, which emits a first waveband light, includes a substrate and a first phosphor layer. The first phosphor layer includes a first phosphor agent and a second phosphor agent. The first phosphor agent is formed on the substrate for converting the first waveband light into a second waveband light. The second waveband light comprises a first color light and a second color light. The second phosphor agent is distributed over the first phosphor agent for converting the first waveband light into the second color light so as to increase the luminous intensity of the second color light. Therefore, the luminous intensity of the second color light can be effectively increased.

A light source device including: a light source section which generates any one of blue light, red light, and green light; a phosphor which generates a fluorescence including the two colors other than the color of the light emitted from the light source section; a color-changing section which changes one of the two colors of the fluorescence emitted from the phosphor to another color regularly and irradiates it to the image-forming element; and a light path-switching section which switches a light path in which a fluorescence excited by the color light emitted from the light source section passes towards the color-changing section and a light path in which the color light emitted from the light source section passes towards the image-forming element regularly.

A phosphor device of an illumination system emitting a first waveband light and having an optical path includes a first section and a first phosphor agent. The first phosphor agent is coated on the first section. The first waveband light is received and converted into a second waveband light by the first phosphor agent. The second waveband light is directed to the optical path. The range of the spectrum of the second waveband light includes at least a first color light and a second color light, so that the first color light or the second color light is separated from the second waveband light along the optical path. Therefore, the diversity of the design of the phosphor device is enhanced, the manufacturing cost and the size of product are reduced, and the color purity is enhanced.

A projector can prevent a flicker from being caused by rotation of a rotating phosphor plate. The projector includes a solid-state light source that emits excitation light, a rotating phosphor plate that converts the excitation light into phosphor light, a liquid-crystal light modulating device that modulates the light from the rotating phosphor plate, a projection optical system that projects the modulated light onto a screen, and a control device that controls the solid-state light source and the rotating phosphor plate so as to satisfy any one of a conditional expression A=B, a conditional expression A=2B, and a conditional expression |A−B| is greater than or equal to 20 and |A−2B| is greater than or equal to 20, where A represents a pulse width modulation control frequency in hertz of the solid-state light source and B represents a rotation frequency in hertz of the rotating phosphor plate.