The present application is based on, and claims priority from JP Application Serial Number 2020-051191, filed Mar. 23, 2020, and JP Application Serial Number 2020-148342, filed Aug. 2, 2017, the disclosure of which is hereby incorporated by reference herein in its entirety.

BACKGROUND

1. Technical Field

The present disclosure relates to a light source device and a projector.

2. Related Art

As a light source device used for a projector, there is proposed a light source device using fluorescence which is emitted from a phosphor when irradiating the phosphor with excitation light emitted from a light emitting element. In JP-T-2008-521233 (the term “JP-T” as used herein means a published Japanese translation of a PCT patent application), there is disclosed a light source device which is provided with a wavelength conversion member including a phosphor and shaped like a flat plate, and a light emitting diode (LED) for emitting the excitation light, and which makes the excitation light enter the wavelength conversion member from a surface large in area out of a plurality of surfaces of the wavelength conversion member to emit the converted light from a surface small in area of the wavelength conversion member.

When generating illumination light having a white color in a related-art light source device, since a blue light source unit for generating blue light becomes necessary in addition to a light source unit for emitting the fluorescence, there is a problem that a device configuration grows in size.

SUMMARY

In view of the problems described above, according to a first aspect of the present disclosure, there is provided a light source device including a first light source configured to emit first light having a first wavelength band, a second light source configured to emit second light having a second wavelength band, a wavelength conversion section which includes a phosphor, and which is configured to convert the first light emitted from the first light source into third light in a third wavelength band different from the first wavelength band, a polarization splitting/combining element which is disposed in a light path of the second light, and which has a polarization splitting function with respect to the second light, a dichroic mirror configured to reflect the second light which is emitted from the second light source and which proceeds via the polarization splitting/combining element, toward the polarization splitting/combining element, and transmit the third light emitted from the wavelength conversion section, a retardation plate disposed between the polarization splitting/combining element and the dichroic mirror in the light path of the second light, a diffusion section disposed between the polarization splitting/combining element and the dichroic mirror in the light path of the second light, and a condensing optical section configured to collect the third light which is emitted form the wavelength conversion section and is transmitted through the dichroic mirror, and the second light reflected by the dichroic mirror, wherein the condensing optical section includes a first end part, a second end part, and a reflecting part configured to reflect incident light, the second light which is emitted from the second light source and proceeds via the polarization splitting/combining element enters the condensing optical section through the second end part, passes through the condensing optical section, and is emitted from the first end part, and enters the dichroic mirror, the second light which is reflected by the dichroic mirror enters the condensing optical section through the first end part, passes through the condensing optical section, and is emitted from the second end part, and enters the polarization splitting/combining element, the third light which is emitted from the wavelength conversion section and is then transmitted through the dichroic mirror enters the condensing optical section through the first end part, passes through the condensing optical section, and is emitted from the second end part, and enters the polarization splitting/combining element, and the polarization splitting/combining element combines the second light reflected by the dichroic mirror and the third light emitted from the wavelength conversion section with each other to generate composite light.

According to a second aspect of the present disclosure, there is provided a projector including the light source device according to the first aspect of the present disclosure, a light modulation device configured to modulate light from the light source device in accordance with image information, and a projection optical device configured to project the light modulated by the light modulation device.

