US-20260126713-A1 - LIGHT SOURCE DEVICE AND PROJECTOR

US20260126713A1US 20260126713 A1US20260126713 A1US 20260126713A1US-20260126713-A1

Abstract

A light source device according to the present disclosure includes a light source section that emits first light in a first wavelength band; a wavelength conversion layer configured to convert the first light into second light in a second wavelength band; and a translucent substrate having a first face and a second face, the wavelength conversion layer being provided on the first face. The first light emitted from the light source section enters the translucent substrate from the second face, passes through the translucent substrate, and enters the wavelength conversion layer from the first face. A part of the second light converted by the wavelength conversion layer enters the translucent substrate from the first face. The light source device includes a first reflective surface that intersects the first face and the second face of the translucent substrate and reflects the second light.

Inventors

Namiko ONOTA

Assignees

SEIKO EPSON CORPORATION

Dates

Publication Date: 20260507
Application Date: 20251104
Priority Date: 20241105

Claims (13)

1 . A light source device comprising: a light source section that emits first light in a first wavelength band; a wavelength conversion layer that converts the first light into second light in a second wavelength band different from the first wavelength band; and a translucent substrate including a first face and a second face opposite to the first face, the wavelength conversion layer being arranged on the first face, wherein the first light emitted from the light source section enters the translucent substrate through the second face, passes through the translucent substrate, and reaches the wavelength conversion layer on the first face, subsequently, a part of the second light converted by the wavelength conversion layer is emitted toward the translucent substrate through the first face, and it includes a first reflective surface that intersects the first face and the second face of the translucent substrate and reflects the second light.
2 . The light source device according to claim 1 , wherein the first reflective surface is perpendicular to both the first face and the second face.
3 . The light source device according to claim 1 , wherein the first reflective surface is provided at a position that overlaps with the wavelength conversion layer when viewed from a direction perpendicular to the first face.
4 . The light source device according to claim 1 , further comprising: a first support substrate that supports the translucent substrate, wherein the first support substrate is rotatable about a rotation shaft extending in a normal line direction of the first face and the first reflective surface is provided at an interface between the translucent substrate and the first support substrate.
5 . The light source device according to claim 4 , wherein the first support substrate is made of metal.
6 . The light source device according to claim 4 , wherein the first support substrate is made of the same material as the translucent substrate.
7 . The light source device according to claim 4 , further comprising: a second reflective surface that is provided on the surface of the translucent substrate opposite the interface and that reflects the second light.
8 . The light source device according to claim 7 , wherein the second reflective surface is perpendicular to both the first face and the second face.
9 . The light source device according to claim 7 , wherein the second reflective surface is provided at a position overlapping the wavelength conversion layer when viewed from a direction perpendicular to the first face.
10 . The light source device according to claim 9 , further comprising: a second support substrate that is provided on a side of the translucent substrate opposite the first support substrate and that supports the translucent substrate, wherein the second reflective surface is provided at an interface between the translucent substrate and the second support substrate.
11 . The light source device according to claim 7 , wherein each of the first and second reflective surfaces is formed of a reflective layer comprising any one of a dielectric multilayer film, a metal film, or an adhesive layer containing metal.
12 . The light source device according to claim 1 , further comprising: a dichroic layer that is provided between the first face of the translucent substrate and the wavelength conversion layer, that transmits the first light, and that reflects the second light.
13 . A projector comprising: the light source device according to claim 1 ; a light modulation device that modulates light emitted from the light source device in accordance with image information; and a projection optical device that projects light modulated by the light modulation device.

Description

The present application is based on, and claims priority from JP Application Serial Number 2024-193458, filed November 5, 2024, 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 in a projector, a light source device has been proposed that uses fluorescence emitted when a phosphor is irradiated with excitation light emitted from a light emitting element. JP-A-2012-3923 discloses a light source device that causes excitation light to enter a phosphor layer formed on a transparent substrate and generates illumination light including fluorescence and a part of the excitation light. In the light source device, the excitation light emitted from the excitation light source is sequentially transmitted through the transparent substrate and the dichroic layer, and then enters the phosphor layer. Among the fluorescence emitted in all directions from the phosphor layer, the fluorescence that travels toward the transparent substrate is reflected by the dichroic layer and extracted from the side opposite to the transparent substrate. In the light source device described in JP-A-2012-3923, in order to extract the fluorescence in a desired direction, that is, from the side opposite to the transparent substrate, a dichroic layer that transmits the excitation light and reflects the fluorescence is provided between the transparent substrate and the phosphor layer. However, due to the optical characteristics of the dichroic layer, the fluorescence incident on the dichroic layer is transmitted through the dichroic layer and leaks into the transparent substrate. The fluorescence leaking into the transparent substrate may propagate through the transparent substrate while undergoing total internal reflection, and there is a possibility that fluorescence may be emitted out from the side surface of the transparent substrate. This fluorescence is difficult to use as illumination light, and there is a problem that the use efficiency of the fluorescence is reduced. SUMMARY In order to solve the above problems, a light source device according to an aspect of the present disclosure includes a light source section that emits first light in a first wavelength band; a wavelength conversion layer that converts the first light into second light in a second wavelength band different from the first wavelength band; and a translucent substrate including a first face, a second face opposite to the first face, and the wavelength conversion layer that is arranged on the first face. The first light emitted from the light source section enters the translucent substrate through the second face, passes through the translucent substrate, and reaches the wavelength conversion layer on the first face. subsequently, a part of the second light converted by the wavelength conversion layer is emitted toward the translucent substrate through the first face. The light source device includes a first reflective surface that intersects the first face and the second face of the translucent substrate and reflects the second light. A projector according to another aspect of the disclosure includes the illuminator according to the aspect of the disclosure, a light modulator that modulates light outputted from the illuminator in accordance with image information, and a projection optical device that projects light modulated by the light modulation device. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is schematic configuration diagram of a projector according to a first embodiment. FIG. 2 is schematic configuration diagram of the light source device according to the first embodiment. FIG. 3 is a front view of the wavelength conversion device. FIG. 4 is a cross-sectional view of the wavelength conversion section taken along line IV-IV in FIG. 3. FIG. 5 is a diagram illustrating a problem of a light source device in the related art. FIG. 6 is a cross-sectional view of a wavelength conversion section in a light source device according to a second embodiment. FIG. 7 is a cross-sectional view of a wavelength conversion section in a light source device according to a third embodiment. DESCRIPTION OF EMBODIMENTS FIRST EMBODIMENT Hereinafter, a first embodiment of the present disclosure will be described with reference to the drawings. In the drawings used in the following description, in order to make features easy to understand, characteristic portions may be enlarged for convenience, and the dimensional ratio of each component may be changed as appropriate. FIG. 1 is schematic configuration diagram of a projector according to the present embodiment. As shown in FIG. 1, a projector 10 of the present embodiment is a projection-type image display device that displays an image on a screen SCR. The projector 10 includes a light source device 100, a color separation optical system 200, a light modulation de