JP2008091143A - Light source device and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a light source device capable of receiving light which is radially emitted from a solid light source and orienting the light to a predetermined direction and a projector equipped with this light source device. <P>SOLUTION: In the light guide member 6 of the light source device 41A, the outer surface 6B of the peripheral light guide 7 connected to the second surface area 52 of the solid light source 5 is made total-reflective and a reflection layer P1 is provided between the peripheral light guide 7 and the central light guide 8 connected to the first surface area 52 of the solid light source 5. The light exit surfaces 7A and 7B of the light guides 7 and 8 respectively face to a predetermined direction. This structure can orient, to a predetermined direction, light which is transferred to the light exit surface 7A of the peripheral light guide 7 from the second surface area 52 of the solid light source 5 through the peripheral light guide 7 and light which is transferred to the light exit surface 8A of the central light guide 8 from the first surface area 51 of the solid light source 5 through the peripheral light guide 8. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light source device including a solid light source and a projector including the light source device.

  2. Description of the Related Art Conventionally, a projector including a light source, a light modulation device that modulates a light beam emitted from the light source according to image information to form an optical image, and a projection optical device that magnifies and projects the formed optical image is known. It has been. As a light source for such a projector, a discharge light source such as a high-pressure mercury lamp has been used. Recently, solid light sources such as LEDs (Light Emitting Diodes) that have high photoelectric conversion efficiency and low power consumption due to demands for environmental problems. A projector using a light source device having a light source has been proposed (see, for example, Patent Document 1).

  In the projector described in Patent Document 1, the LED includes an LED chip mounted on the LED package, and a dome-shaped lens cap that covers a side surface and an upper surface of the LED chip. The light emitted from the LED is aligned in a predetermined optical axis direction determined by the optical component by an optical component such as a lens array disposed in the latter stage of the optical path, and the optical axis direction. The in-plane illuminance in the plane orthogonal to the plane is made uniform, and the liquid crystal panel is irradiated to form an optical image.

JP 2006-54352 A

  However, in the LED described in Patent Document 1, although the LED chip is covered with the lens cap, the light emitted from the LED chip does not enter the lens array because it is emitted radially from the lens cap. There was a problem that light was not used for image formation. For this reason, there has been a problem that the light utilization efficiency is lowered, and the brightness of the projected image is lowered.

  An object of the present invention is to provide a light source device capable of emitting light emitted radially from a solid light source in a predetermined direction and a projector including the light source device.

  A light source device of the present invention is mounted on an element substrate and emits light by application of a predetermined voltage, a light guide member connected to the solid light source and guiding light incident from the solid light source, The solid-state light source includes a first surface portion that is a surface along the element substrate and opposite to the side facing the element substrate, and the first surface portion of the solid-state light source. The light guide member is disposed on the outermost periphery of the light guide member, and at least the second surface portion and one end of the solid light source are connected to each other. An outer peripheral light guide, a central light guide disposed inside the outer light guide and connected to at least the first surface and one end of the solid light source; and the outer guide. A reflective layer provided between an optical part and the central light guide part, A reflection surface is formed on the outer peripheral surface of the peripheral light guide, and the outer peripheral light guide transmits light incident from the one end connected to at least the second surface of the solid light source to the other. The light is guided to the end side, and the center-side light guide unit guides light incident from the one end connected to at least the first surface part of the solid-state light source to the other end, The end surfaces of the other end portions of the outer peripheral side light guide portion and the center side light guide portion are exit surfaces from which the guided light is emitted, and the exit surface of the outer peripheral side light guide portion and the center The exit surface of the side light guide unit is characterized by being directed in a predetermined direction.

According to the present invention, since the reflective layer is provided between the center side light guide unit and the outer periphery side light guide unit, the light incident on the center side light guide unit from at least the first surface of the solid light source is Then, the light travels in the central light guide without entering the outer light guide, and is emitted from the exit surface of the central light guide. In addition, the light incident on the outer peripheral light guide from at least the second surface of the solid light source is reflected between the central light guide and the outer light guide, and the outer periphery of the outer light guide. While repeating reflection with the reflecting surface formed on the surface, the light travels in the outer light guide part and is emitted from the exit surface of the outer light guide part.
Here, since the exit surface of each light guide unit is oriented in a predetermined direction, the light incident on each light guide unit from the solid light source is aligned in a predetermined direction from each exit surface of each light guide unit. Can be injected. Therefore, when such a light source device of the present invention is used for a projector, for example, the light emitted from the solid light source can be emitted in a predetermined direction, so that it is emitted from the side of the solid light source. Light can be easily used for image formation.

In the present invention, the outer peripheral surface of the outer peripheral side light guide unit and the outer peripheral surface of the center side light guide unit have curved surfaces such that light emitted from the exit surface of each light guide unit is along a predetermined direction. It is preferable.
According to the present invention, since the outer peripheral surface of the outer peripheral side light guide unit and the outer peripheral surface of the center side light guide unit have a curved shape in which light emitted from the emission surface of each light guide unit is along a predetermined direction. The light incident on each light guide from the solid light source can be emitted from each exit surface along a direction perpendicular to the exit surface. Thereby, the light incident on each light guide from the solid light source can be emitted more uniformly in a predetermined direction from the emission surface of each light guide.

In this invention, it is preferable that the outer peripheral surface of the said outer peripheral side light guide part and the said center side light guide part has planar shape.
According to the present invention, since the outer peripheral surfaces of the outer peripheral side light guide part and the center side light guide part have a planar shape, the shape of each light guide part can be facilitated and each assembly can be easily performed. Can do. Therefore, it is possible to simplify the manufacture of each light guide unit and, consequently, the light source device.

In the present invention, the exit surface of the center-side light guide portion bulges in the light emission direction, and the light emitted from the center-side light guide portion is substantially normal to the exit surface of the light guide member as a whole. It is preferable to have a lens effect that aligns in the direction.
According to the present invention, since the exit surface of the center-side light guide section bulges in the direction of light emission, light is emitted from the exit surface inclining outward from the center of the center-side light guide section. This can be suppressed, and light can be reliably emitted in a predetermined direction from the emission surface of the center-side light guide unit.

In the present invention, the area ratio between the exit surface of the outer periphery-side light guide unit and the exit surface of the center-side light guide unit is determined by the amount of light incident on the outer periphery-side light guide unit and the center-side light guide unit. It is preferable that the ratio is approximately equal to the ratio of the light quantity.
According to the present invention, the area ratio of the exit surfaces of the outer peripheral side light guide part and the center side light guide part is substantially equal to the ratio of the amount of light incident from the solid light source to each light guide part. The in-plane illuminance in the plane perpendicular to the predetermined direction of the light emitted from the exit surface of the part can be made uniform, and consequently the in-plane illuminance in the plane orthogonal to the predetermined direction of the light emitted from the light source device can be made uniform.

In the present invention, the center-side light guide section includes at least a first center light guide section and a second center light guide section, and is configured in a multilayer structure in which a reflective layer is interposed between the light guide sections. It is preferable that the area ratio of the exit surface of each light guide part constituting the center side light guide part is substantially equal to the ratio of the amount of light incident on each light guide part.
According to the present invention, the center-side light guide section is configured to have at least a two-layer structure including at least the first center light guide section and the second center light guide section, and each light guide section constituting the center-side light guide section. Since the area ratio of the light exit surface is substantially equal to the ratio of the amount of light incident on each light guide, the in-plane illuminance in the plane perpendicular to the predetermined direction of the light emitted from the exit surface of each light guide Can be made uniform, and by extension, the in-plane illuminance in the plane perpendicular to the predetermined direction of the light emitted from the light source device can be made more uniform.

According to another aspect of the invention, a projector includes the light source device described above, a light modulation device that modulates light emitted from the light source device according to image information, and a projection optical device that projects the modulated light. It is characterized by that.
According to the present invention, the same effects as those of the light source device described above can be obtained, and almost all of the light emitted from the solid light source can be used, so that the light use efficiency can be improved. Thereby, the brightness of the formed image can be improved.

In the present invention, a polarization conversion device that aligns the polarization direction of incident light is disposed downstream of the light path of the light source device, and an exit surface of the light source device is formed to be substantially similar to the incident surface of the polarization conversion device. Preferably it is.
According to the present invention, the polarization converter includes a polarization separation layer that transmits polarized light in one direction and reflects the other polarized light out of the light incident through the incident surface, and the reflected other polarized light. A reflective layer that reflects light in a direction along the direction of transmission of polarized light in one direction, and the separated polarized light in one direction and the other polarized light are disposed on the optical path, and the polarization direction of incident light is changed. And a retardation layer for conversion. Thereby, the random polarized light beam emitted from the light source device is converted into a light beam composed of approximately one type of polarized light by the polarization conversion device, and emitted toward the rear of the optical path.
Here, according to the present invention, since the exit surface of the light source device is formed to be substantially similar to the entrance surface of the polarization conversion device, the exit surface of the light source device and the entrance surface of the polarization conversion device are substantially the same. In the case of the size, by arranging the surfaces close to each other, almost all of the light emitted from the exit surface of the light source device can be incident on the entrance surface of the polarization conversion device.
In addition, when the exit surface of the source device and the entrance surface of the polarization conversion device have different sizes, the light emitted from the exit surface of the light source device is enlarged or reduced by a lens so that the light exits from the exit surface of the light source device. Almost all of the emitted light can be incident on the incident surface of the polarization conversion device. Therefore, the light use efficiency can be further improved.

[First Embodiment]
Hereinafter, a projector 1 according to a first embodiment of the present invention will be described with reference to the drawings.
[Configuration of Projector 1]
FIG. 1 is a schematic diagram illustrating a configuration of a projector 1 according to the present embodiment.
The projector 1 according to the present embodiment modulates a light beam emitted from a light source according to image information to form an optical image, and enlarges and projects the optical image by a projection lens 3. As shown in FIG. 1, the projector 1 includes an optical unit 4 that forms an optical image corresponding to image information, a projection lens 3 that magnifies and projects the formed optical image, and an exterior housing 2 that houses them. And is configured.
Although not shown in FIG. 1, in the exterior casing 2, a space other than the projection lens 3 and the optical unit 4 is provided in a cooling unit constituted by a cooling fan or the like that cools the inside of the projector 1. It is assumed that a power supply unit that supplies electric power to each of the components and a control unit that controls the entire projector 1 are arranged.

[Configuration of exterior casing 2 and projection lens 3]
The exterior housing 2 is made of a synthetic resin, and as shown in FIG. 1, the exterior housing 2 is formed in an overall substantially rectangular parallelepiped shape in which the projection lens 3, the optical unit 4, and the like are housed and arranged. Although not shown in detail, the exterior housing 2 includes an upper case that configures the top surface, front surface, back surface, and left and right side surfaces of the projector 1, and a lower case that configures the bottom surface, front surface, and back surface of the projector 1, respectively. The upper case and the lower case are fixed to each other with screws or the like. The exterior casing 2 is not limited to a synthetic resin, but may be formed of other materials, for example, a metal or the like.
The projection lens 3 is a projection optical device that forms an optical image (color image) formed by the optical unit 4 on a screen (not shown) and enlarges and projects the optical image. The projection lens 3 is configured as a combined lens in which a plurality of lenses are housed in a cylindrical lens barrel.

[Configuration of Optical Unit 4]
The optical unit 4 modulates the light beam emitted from the light source according to image information under the control of the control unit to form an optical image. As shown in FIG. 1, the optical unit 4 includes a light source device 41A (41AR, 41AG, 41AB), a uniform illumination optical device 42 (42R, 42G, 42B), and an image forming device 43. Yes.

  The light source device 41A (the light source device that emits red light is 41AR, the light source device that emits green light is 41AG, and the light source device that emits blue light is 41AB) will be described in detail later, but each is composed of LED elements. The solid-state light source 5 that emits each color light and the light guide member 6 connected to the solid-state light source 5 are configured. Each color light emitted from the solid light source 5 is guided by the light guide member 6 and then emitted to the uniform illumination optical device 42 in the latter stage of the optical path.

  The uniform illumination optical device 42 is an illumination optical system that uniformly illuminates an image forming area of a liquid crystal panel 431 constituting an image forming device 43 described later. As shown in FIG. 1, these uniform illumination optical devices 42 (42R is an illumination optical device that emits red light, 42G is an illumination optical device that emits green light, and 42B is an illumination optical device that emits blue light). , Respectively, are provided with a polarization conversion device 421 and a rod integrator 422.

As will be described in detail later, the polarization conversion device 421 converts the light beam incident from the light source device 41A into substantially one type of polarized light beam and emits it to the rod integrator 422 in the latter stage of the optical path.
The rod integrator 422 is made of a translucent material such as glass and has a rectangular cross section. By repeatedly reflecting the light beam incident from the polarization conversion device 421 inside, the in-plane illuminance of the light beam is made uniform from the exit end surface. Eject.

  The image forming apparatus 43 modulates the incident light beam according to image information to form a color image. The image forming apparatus 43 includes three liquid crystal panels 431 as light modulators (the liquid crystal panel for red light is 431R, the liquid crystal panel for green light is 431G, and the liquid crystal panel for blue light is 431B), and these Three incident side polarizing plates 432 arranged on the light beam incident side of each liquid crystal panel 431, three emission side polarizing plates 433 arranged on the light emission side of each liquid crystal panel 431, and a color combining optical device And a cross dichroic prism 434.

Each incident-side polarizing plate 432 receives light of each color whose polarization direction is aligned in substantially one direction by the polarization conversion device 421, and the incident-side polarizing plate 432 aligns the incident light beam by the polarization conversion device 421. Only polarized light having substantially the same direction as the polarization direction of the emitted light beam is transmitted and other light beams are absorbed. The incident-side polarizing plate 432 has a configuration in which a polarizing layer is pasted on a translucent substrate such as sapphire glass or quartz.
Although not shown in detail, the liquid crystal panel 431 as a light modulator has a configuration in which liquid crystal, which is an electro-optical material, is hermetically sealed between a pair of transparent glass substrates. Accordingly, the alignment state of the liquid crystal is controlled, and the polarization direction of the polarized light beam transmitted through the incident side polarizing plate 432 is modulated.

The exit side polarizing plate 433 transmits only the light beam having a polarization direction orthogonal to the transmission axis of the light beam in the incident side polarizing plate 432 out of the light beam emitted from the liquid crystal panel 431 and absorbs the other light beams.
The cross dichroic prism 434 forms an optical image (color image) by combining the modulated light modulated for each color light transmitted through the exit-side polarizing plate 433. The cross dichroic prism 434 has a substantially square shape in plan view in which four right-angle prisms are bonded together, and two dielectric multilayer films are formed at the interface where the right-angle prisms are bonded together. These dielectric multilayer films transmit color light through the exit side polarizing plate 433 disposed on the side facing the projection lens 3 (G color light side), and the remaining two exit side polarizing plates 433 (R color light side and B color side). Reflects colored light via the colored light side). In this way, the color lights modulated by the incident-side polarizing plates 432, the liquid crystal panels 431, and the emission-side polarizing plates 433 are combined to form a color image.

[Configuration of Polarization Conversion Device 421]
Hereinafter, the configuration of each polarization conversion device 421 will be described.
FIG. 2 is a diagram for explaining the configuration of the light source device 41 </ b> A and the polarization conversion device 421. In FIG. 2, a cross section of the light source device 41A is shown.
The polarization conversion device 421 is disposed between the light source device 41A and the rod integrator 422, and converts a light beam having various types of randomly polarized light emitted from the light source device 41A into a light beam composed of substantially one type of linearly polarized light. To the rod integrator 422.

  Specifically, as shown in FIG. 2, the polarization conversion device 421 includes a plate glass 4211 having an incident surface 421 </ b> A arranged to face the exit surface 6 </ b> A of the light guide member 6 of the light source device 41 </ b> A, and an inside of the plate glass 4211. And a polarization separation film 4212 that transmits the S-polarized light and reflects the P-polarized light, and is formed on the inclined surface of the plate glass 4211, and is disposed on the polarization separation film 4212. A reflective film 4213 disposed substantially parallel to the light-emitting side of the plate glass 4211 and a ½ phase difference plate 4214 disposed at a position corresponding to the reflective film 4213 are provided. The incident surface 421A of the polarization conversion device 421 is formed in a shape that halves the length in the longitudinal direction of the exit surface 421B in which the ratio of the length in the longitudinal direction to the lateral direction is 16: 9, The length ratio between the short side direction and the long side direction on the incident surface 421A is formed to a ratio of 8: 9. In addition, the longitudinal direction of the emission surface 421B in the present embodiment corresponds to the vertical direction of the paper surface in FIG.

  When the light beam emitted from the light source device 41A is incident on the incident surface 421A, the light is first separated into P-polarized light and S-polarized light by the polarization separation film 4212. That is, the S-polarized light passes through the polarization separation film 4212 as it is, and is emitted toward the rod integrator 422 from a portion of the emission surface 421B of the plate glass 4211 where the 1/2 phase difference plate 4214 is not installed. On the other hand, the P-polarized light is reflected by the polarization separation film 4212 and the optical path is rotated approximately 90 degrees toward the reflection film 4213. The P-polarized light reflected by the polarization separation film 4212 and traveling toward the reflection film 4213 is reflected again by the reflection film 4213, and the optical path is rotated by approximately 90 degrees toward the half phase plate 4214. The P-polarized light that has entered the ½ phase difference plate 4214 is converted into S-polarized light with the phase shifted by ½π, and is emitted toward the rod integrator 422. Accordingly, the randomly polarized light beam emitted from the light source device 41A is converted into a light beam composed of substantially one type of S-polarized light by the polarization conversion device 421 and is emitted toward the rod integrator 422.

  As shown in FIG. 1, a light beam that is incident on the rod integrator 422 and has a uniform in-plane illuminance is transmitted through a liquid crystal panel and converted into P-polarized light, and forms a color image corresponding to each color light. The light enters the prism 434. In the prism 434, the red light and the blue light reflected by the dielectric multilayer film and the green light transmitted through the dielectric multilayer film are combined and enlarged and projected from the projection lens 3 onto a screen (not shown). In the present embodiment, the polarization conversion device 421 converts the incident light from the light source device 41A into S-polarized light, but may convert it into P-polarized light.

[Configuration of Light Source Device 41A]
Hereinafter, the configuration of each light source device 41A will be described.
FIG. 3 is a perspective view showing the light source device 41A, and FIG. 4 is a front view of the light source device 41A.
As described above, the light source device 41 </ b> A includes the solid light source 5 and the light guide member 6 connected to the solid light source 5.

As shown in FIGS. 2 and 3, the solid-state light source 5 is configured by a substantially rectangular parallelepiped LED element, and a first surface portion 51 that is a surface opposite to the side facing the element substrate 10 when a predetermined voltage is applied. And a predetermined color light is emitted from the second surface portion 52 orthogonal to the first surface portion 51.
The light guide member 6 is made of glass, translucent resin, or the like, and has one end connected to the first surface portion 51 and the second surface portion 52 of the solid light source 5 as shown in FIGS. 2 and 3. The light incident from the solid light source 5 is guided to the exit surface 6A side which is the end surface of the other end.

  As shown in FIG. 3, the light guide member 6 is disposed on the outermost periphery of the light guide member 6, and has a substantially cylindrical outer peripheral side light guide portion whose one end is connected to the second surface portion 52 of the solid light source 5. 7, a substantially columnar center-side light guide 8 that is arranged inside the outer light guide 7 and has one end connected to the first surface 51 of the solid light source 5, and the outer light guide 7. And the first reflection layer P1 provided between the center side light guide portion 8 and the center side light guide portion 8.

  The center-side light guide 8 is disposed on the outermost periphery of the center-side light guide 8 and has one end connected to the outer region 511 of the first surface portion 51 of the solid light source 5. A light guide part 81, a substantially columnar second center light guide part 82 disposed inside the first center light guide part 81 and having one end connected to the inner region 512 of the solid light source 5; A second reflective layer P2 provided between the first center-side light guide part 81 and the second center-side light guide part 82 is provided.

That is, in the light guide member 6, the first center-side light guide unit 81 is disposed inside the outer peripheral-side light guide unit 7 via the first reflective layer P <b> 1, and further inside the first center-side light guide unit 81. A multilayer structure in which the second center-side light guide portion 82 is disposed via the second reflective layer P2 is formed.
Then, from the exit surface 7A of the outer peripheral side light guide unit 7, the exit surface 81A of the first center side light guide unit 81, and the exit surface 82A of the second center side light guide unit 82, the exit surface 6A of the light guide member 6 is obtained. Is configured. As shown in FIG. 4, the light exiting surface 6 </ b> A of the light guide member 6 is formed so that the ratio of the length in the short side direction to the length in the long side direction is a ratio of 8: 9. The surface is substantially similar to the surface 421A (and is approximately the same size as the incident surface 421A). Further, the exit surface 6A of the light guide member 6 is disposed close to the incident surface 421A of the polarization conversion device 421.

  In addition, the outer peripheral side light guide part 7 is comprised with the high refractive index member, and the outer peripheral surface of the outer peripheral side light guide part 7 is formed in the total reflection surface which totally reflects the incident light. Moreover, the outer peripheral surface of each light guide part 7,81,82 is formed in a gentle curved surface (small curvature), and although mentioned later in detail, the light which injected into each light guide part 7,81,82 from the solid light source 5 Can be emitted from the emission surfaces 7A, 81A, 82A of the light guides 7, 81, 82 along a direction substantially perpendicular to the emission surfaces 7A, 81A, 82A.

  As shown in FIG. 3, the light guide member 6 connects the exit surface 6 </ b> A, which is substantially similar to the entrance surface 421 </ b> A of the polarization conversion device 421, and each side of the exit surface 6 </ b> A and each side of the solid light source 5. The peripheral surface 6B is composed of two curved surfaces, and is formed in a divergent shape that expands from the proximal end side connected to the solid light source 5 toward the distal end side where the emission surface 6A is formed.

The exit surfaces 7A, 81A, and 82A of the outer peripheral side light guide unit 7, the first center side light guide unit 81, and the second center side light guide unit 82 are all in a predetermined direction, that is, the incident surface 421A of the polarization conversion device 421. It faces the opposite direction. Further, as shown in FIG. 1, the exit surface 82A of the second center-side light guide section 82 bulges toward the front end side of the light exit direction, and a lens that aligns the light incident on the exit surface 82A in the exit direction. Has an effect.
Furthermore, the area ratio of the exit surfaces 7A, 81A, 82A of the outer peripheral light guide 7, the first central light guide 81, and the second central light guide 82 is determined from the second surface 52 of the solid light source 5. The amount of light incident on the outer peripheral light guide unit 7, the amount of light incident on the first central light guide unit 81 from the outer region 511 of the solid light source 5, and the second central light guide unit 82 from the inner region 512 of the solid light source 5. Is approximately equal to the ratio of the amount of light incident on the.

In the light source device 41 </ b> A as described above, when a voltage is applied to the solid light source 5, predetermined color light is emitted from the first surface portion 51 and the second surface portion 52 of the solid light source 5.
The light emitted from the second surface portion 52 of the solid-state light source 5 travels in the outer peripheral light guide 7 while repeating reflection between the outer peripheral surface of the outer peripheral light guide 7 and the first reflective layer P1, From the exit surface 7A, it is ejected to the outside along a direction substantially perpendicular to the exit surface 7A.
Similarly, the light emitted from the outer region 511 of the solid-state light source 5 travels in the first central light guide unit 81 while being repeatedly reflected between the first reflective layer P1 and the second reflective layer P2. The light is emitted from the emission surface 81A to the outside along a direction substantially perpendicular to the emission surface 81A.
The light emitted from the inner region 512 of the solid-state light source 5 travels in the second center-side light guide unit 82 while being repeatedly reflected between the second reflective layers P2, and is approximately from the emission surface 82A to the emission surface 82A. Injected outside along the vertical direction.

  Accordingly, the light emitted from the second surface portion 52, the outer region 511, and the inner region 512 of the solid light source 5 travels through the light guides 7, 81, 82 and then from each of the light emission surfaces 7A, 81A, 82A. The light is emitted to the outside along a direction substantially perpendicular to the emission surfaces 7A, 81A, and 82A. At this time, since each of the exit surfaces 7A, 81A, and 82A is oriented in a predetermined direction, that is, a direction facing the entrance surface 421A of the polarization conversion device 421 disposed at the latter stage of the optical path, the second surface portion of the solid light source 5 is provided. 52, the light emitted from the outer region 511 and the inner region 512 and guided by the light guides 7, 81, 82 is emitted in a predetermined direction, that is, in the direction of the incident surface 421A of the polarization conversion device 421. can do.

  In addition, since the exit surface 6A of the light guide member 6 is formed in a substantially similar shape to the incident surface 421A of the polarization conversion device 421 and is disposed close to the incident surface 421A of the polarization conversion device 421, the light source device 41A. The light exiting from the exit surface 6A is incident on the entrance surface 421A of the polarization conversion device 421. As a result, it is possible to use light that has not been used for image formation since it is not incident on the incident surface 421A of the polarization conversion device 421 after being emitted from the second surface portion 52 of the solid-state light source 5 and the like. Efficiency can be improved.

  Note that the outer peripheral surfaces of the outer peripheral side light guide unit 7, the first central side light guide unit 81, and the second central side light guide unit 82 are all formed in a gently curved surface shape (small curvature), and are solid-state light sources. 5 can be effectively emitted from the emission surfaces 7A, 81A, 82A of the light guides 7, 81, 82 along a direction substantially perpendicular to the emission surfaces 7A, 81A, 82A. it can. Thereby, the light inject | emitted from each output surface 7A, 81A, 82A of each light guide part 7, 81, 82 can be made into substantially parallel light, and can be inject | emitted more aligned in a predetermined direction. Further, the diffusion of the emitted light beam can be suppressed.

Further, the second center side light guide part 82 is formed in a divergent shape whose cross section expands toward the emission surface 82A, and it is difficult to emit light from the solid light source 5 in a predetermined direction from the emission surface 82A. The exit surface 82A of the second center-side light guide section 82 bulges toward the light emission direction front end side and has a lens effect, so that the second center-side light guide section 82 has a lens effect. It is possible to prevent light from being emitted from the center to the outside and to emit light in a predetermined direction.
Further, the area ratio of the exit surfaces 7A, 81A, 82A of the light guides 7, 81, 82 is the amount of light incident on the light guides 7, 81, 82 from the surfaces 52, 511, 512 of the solid light source 5. Since it is substantially equal to the ratio, in the light emitted from the exit surfaces 7A, 81A, 82A of the light guides 7, 81, 82, the in-plane illuminance in the plane orthogonal to the predetermined direction can be made uniform, As a result, the in-plane illuminance in the plane perpendicular to the predetermined direction of the light beam emitted from the light source device 41A can be made uniform.

According to the projector as described above, the following effects can be obtained.
(1) In the light guide member 6 in the light source device 41 </ b> A, the outer peripheral surface 6 </ b> B of the outer peripheral light guide unit 7 connected to the second surface unit 52 of the solid light source 5 is formed on the total reflection surface. 7 and a first central light guide 81 provided on the inner side of the outer light guide 7 and connected to the outer region 511 of the solid light source 5, a first reflective layer P1 is provided, Between the first center side light guide part 81 and the second center side light guide part 82 provided inside the first center side light guide part 81 and connected to the inner region 512 of the solid light source 5, the second A reflective layer P2 is provided.
At this time, the exit surfaces 7A, 81A, 82A of the light guides 7, 81, 82 are both in a predetermined direction (the direction in which the exit surfaces 7A, 81A, 82A and the entrance surface 421A of the polarization conversion device 421 face each other). ), The light emitted from the second surface portion 52 of the solid light source 5, guided by the outer peripheral light guide 7, and emitted from the emission surface 7 A of the outer light guide 7, and the solid light source 5 is emitted from the first surface portion 51, is guided by the first and second center-side light guide portions 81 and 82, and is emitted from the exit surfaces 81A and 82A of the first and second center-side light guide portions 81 and 82. Can be emitted in a predetermined direction.

(2) The outer peripheral surfaces of the respective light guides 7, 81, 82 are both gently curved surfaces, and light from the solid light source 5 is transmitted from the respective emission surfaces 7A, 81A, 82A to the respective emission surfaces 7A, 81A. , 82A can be effectively ejected along a direction perpendicular to 82A. Thereby, the light emitted from each of the emission surfaces 7A, 81A, and 82A can be made substantially parallel light, and can be emitted more evenly in a predetermined direction.

(3) The second center-side light guide section 82 is formed in a divergent shape whose cross section expands toward the emission surface 82A, and it is difficult to emit light from the solid light source 5 in a predetermined direction from the emission surface 82A. The exit surface 82A of the second center-side light guide section 82 bulges toward the front end side in the light exit direction and has a lens effect, so that the second center-side light guide section 82 extends from the exit surface 82A. It is possible to prevent the light from being emitted inclining to the outside with respect to the central axis, and to emit the light in a predetermined direction.

(4) The area ratio of the exit surfaces 7A, 81A, 82A of the light guides 7, 81, 82 is the surface of the solid light source 5 to which the light guides 7, 81, 82 are connected (second surface 52, Since the ratio of the amount of light incident on the light guides 7, 81, 82 from the outer region 511 and the inner region 512) is substantially equal to each other, the exit surfaces 7A, 81A, 82A of the light guides 7, 81, 82 are provided. The in-plane illuminance in the plane orthogonal to the predetermined direction of the light emitted from the light source can be made uniform, and consequently the in-plane illuminance in the plane orthogonal to the predetermined direction of the emitted light beam of the light source device 41A can be made uniform.
At this time, in the present embodiment, the center-side light guide unit 8 is configured by two layers of the first center-side light guide unit 81 and the second center-side light guide unit 82. However, the center-side light guide unit 8 is further multilayered. And the area ratio of the exit surface of each light guide part constituting the center side light guide part 8 is made substantially equal to the ratio of the amount of light incident on each light guide part, thereby being emitted from the center side light guide part 8. The in-plane illuminance in the plane perpendicular to the predetermined direction of the luminous flux can be made more uniform.

(5) In the projector 1 of the present embodiment, the exit surface 6A of the light source device 41A is formed in a substantially similar shape to the entrance surface 421A of the polarization conversion device 421, and is disposed close to the entrance surface 421A of the polarization conversion device 421. Therefore, almost all the light emitted from the exit surface 6A of the light source device 41A enters the entrance surface 421A of the polarization conversion device 421. As a result, it is possible to use light that has not been used for image formation since it is not incident on the incident surface 421A of the polarization conversion device 421 after being emitted from the second surface portion 52 of the solid-state light source 5 and the like. Efficiency can be improved. Even if the exit surface 6A of the light source device 41A and the entrance surface 421A of the polarization conversion device 421 have different sizes, the exit surface 6A of the light source device 41 is substantially similar to the entrance surface 421A of the polarization conversion device 421. If it is formed in a shape, the light emitted from the exit surface 6A of the light source device 41A is enlarged or reduced by the lens, so that substantially all of the light emitted from the exit surface 6A of the light source device 41A is polarized light conversion device 421. Can be incident on the incident surface 421A.

(6) Since the projector 1 of the present embodiment uses the solid-state light source 5 having the above-described effects as the light source, the in-plane illuminance in the plane perpendicular to the predetermined direction of the emitted light beam can be made uniform, and the screen Illuminance unevenness of the projection image projected onto the projection image can be reduced, and deterioration of the projection image can be suppressed.

[Second Embodiment]
The projector according to the present embodiment has the same configuration as that of the projector 1 described above. However, in the light source device 41A described above, the center-side light guide unit 8 includes first and second center-side light guide units 81 and 82. Although the light source device 41B of the present embodiment is configured in a two-layer structure, it differs from the light source device 41A described above in that the center-side light guide unit 18 is not configured in a multilayer structure. Further, in the light source device 41A described above, the outer peripheral surface of each light guide unit 7, 81, 82 is configured by a curved surface, but in the light source device 41B of the present embodiment, the outer peripheral surface of each light guide unit 17, 18 is The light source device 41A is different from the light source device 41A described above in that it is configured by a plane. In the following description, parts that are the same as or substantially the same as those already described are assigned the same reference numerals and description thereof is omitted.

FIG. 5 is a perspective view showing the light source device 41B according to the present embodiment.
As shown in FIG. 5, the light source device 41 </ b> B includes a solid light source 15 mounted on the element substrate 110 and a light guide member 16 connected to the solid light source 15. The light guide member 16 is formed in a substantially inverted quadrangular frustum shape that expands toward the tip. The light guide member 16 is disposed on the outermost periphery of the light guide member 16 and is connected to the second surface portion 152 of the solid light source 15. A substantially columnar center-side light guide 18 disposed on the inside and connected to the first surface 151 of the solid-state light source 15, and a reflective layer provided between the outer periphery-side light guide 17 and the center-side light guide 18. P11.

  The outer peripheral surfaces of the outer peripheral light guide 17 and the central light guide 18 are both formed from four flat surfaces. Further, the exit surfaces 17A and 18A of the outer peripheral side light guide unit 17 and the center side light guide unit 18 both face the incident surface 421A of the polarization conversion device 421 and face the direction of the incident surface 421A. The exit surface 18A of the center side light guide 18 bulges toward the front end side in the light exit direction and has a lens effect. The area ratio of the exit surfaces 17A and 18A of the outer peripheral light guide 17 and the central light guide 18 is determined by the amount of light incident on the outer light guide 17 from the second surface 152 of the solid light source 15 and the first surface 151. It is adjusted to be approximately equal to the ratio with the amount of light incident on the center side light guide 18.

Even in such a light source device 41B, the exit surfaces 17A and 18A of the light guides 17 and 18 both have a predetermined direction (the direction in which the exit surfaces 17A and 18A and the entrance surface 421A of the polarization conversion device 421 face each other). The light emitted from the second surface 152 of the solid light source 15, guided by the outer peripheral light guide 17, and emitted from the emission surface 17 A of the outer light guide 17, and the solid light source 15. Light that is emitted from the first surface portion 151, guided by the center-side light guide portion 18, and emitted from the exit surface of the center-side light guide portion 18 can be emitted in a predetermined direction.
The projector according to the present embodiment as described above can achieve the same effects as (1) and (3) to (6) among the effects (1) to (6) that can be achieved by the projector 1 described above. In addition, the following effects can be achieved.
(7) Since the outer peripheral surfaces of the outer peripheral side light guide unit 7 and the center side light guide unit 18 are configured by planes, the shapes of the respective light guide units 17 and 18 can be easily made, and the respective assemblies are easily performed. be able to. Accordingly, it is possible to simplify the manufacture of each light guide unit 17, 18, and consequently the light source device 41B.

[Modification of Embodiment]
The best configuration, method, and the like for carrying out the present invention have been disclosed above, but the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of quantity, other details, and the like.
Therefore, the description limited to the shape, quantity and the like disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.

That is, in each of the above embodiments, the exit surface 6A of the light guide member 6 faces the substantially normal direction of the element substrate 10, but the exit surface 6A of the light guide member 6 is inclined with respect to the element substrate 10. However, the present invention is not limited to being oriented in a substantially normal direction of the element substrate 10. The configurations related to the light guide member 6, the exit surface 6 </ b> A, and the element substrate 10 can also be applied to the light guide member 16, the exit surface 16 </ b> A, and the element substrate 110 in the second embodiment.
In each said embodiment, although the outer peripheral side light guide part 7 was connected to the 2nd surface part 52 of the solid light source 5, the outer periphery side light guide part 7 was connected to the 2nd surface part 52 of the solid light source 5 at least. What is necessary is just to connect with a part of 1st surface part 51 of the solid light source 5.
In each said embodiment, although the center side light guide part 8 was connected to the 1st surface part 51 of the solid light source 5, the center side light guide part 8 is connected to the 1st surface part 51 of the solid light source 5 at least. What is necessary is just to connect with a part of 2nd surface part 52 of the solid light source 5. The configurations relating to the outer peripheral light guide 7, the central light guide 8, the solid light source 5, the first surface 51, and the second surface 52 are the outer peripheral light guide 17, the central light guide in the second embodiment. 18, and can be applied to the solid light source 15, the first surface portion 151, and the second surface portion 152.

In each said embodiment, although the outer peripheral side light guide part 7 was comprised by the high refractive index member and the outer peripheral surface was formed in the total reflection surface, a reflective film is provided in an outer peripheral surface, or an outer peripheral surface is reflected. You may form a reflective surface in the outer peripheral surface of the outer peripheral side light guide part 7 by covering with a member.
In each of the above embodiments, no gap is provided between the outer peripheral light guide 7 and the central light guide 8, but between the outer peripheral light guide 7 and the central light guide 8. If a reflective layer is provided, a gap may be provided between the outer circumferential light guide 7 and the central light guide 8. Further, a gap may be provided between the first and second center-side light guides 81 and 82. The configuration related to the outer peripheral side light guide unit 7 and the central side light guide unit 8 can also be applied to the outer peripheral side light guide unit 17 and the central side light guide unit 18 in the second embodiment.
In each said embodiment, although the solid light sources 5 and 15 were comprised in the rectangular parallelepiped shape, you may be formed in the regular hexahedron shape and the column shape, and it is not limited to being comprised in a rectangular parallelepiped shape.

The solid light sources 5 and 15 are configured by LED elements that emit red, blue, and green color light, but may be configured by LED elements that emit white light. Further, the solid light sources 5 and 15 may be composed of other light emitting elements such as organic EL (Electroluminescence) elements in addition to the LED elements.
In each of the above embodiments, only an example of a projector using three light modulation devices (liquid crystal panels) 431 has been described. However, the present invention can be applied to a projector using two or less and four or more light modulation devices 431. The light source device can be applied.

In each of the above embodiments, the transmission type light modulation device 431 having a different light incident surface and light emission surface is used. However, a reflection type light modulation device having the same light incident surface and light emission surface is used. Also good.
In each of the embodiments described above, the light source devices 41A and 41B of the present invention are used as the light source of the liquid crystal type projector 1. However, the light source devices 41A and 41B are also used for a projector using a light modulation device other than liquid crystal such as a device using a micromirror. it can.
Further, in each of the above embodiments, only the example of the front type projector 1 that performs projection from the direction of observing the screen is given. However, the present invention is a rear type that projects from the side opposite to the direction of observing the screen. It can also be applied to a projector.

  The light source device of the present invention can emit light emitted radially from a solid-state light source in a predetermined direction, and thus can be used as a light source for a projector used in home theater or presentation.

1 is a schematic diagram illustrating a configuration of a projector according to a first embodiment of the invention. The figure for demonstrating the structure of the light source device and polarization conversion apparatus of the said embodiment. The perspective view which shows the light source device of the said embodiment. The front view which shows the light source device of the said embodiment. The perspective view which shows the light source device which concerns on 2nd Embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Projector, 3 ... Projection lens (projection optical apparatus) 5, 15 ... Solid light source, 6, 16 ... Light guide member, 6A, 16A ... Outer surface of a light source device, 7, 17 ... Outer peripheral side light guide part, 8 , 18... Central side light guide, 7A, 17A... Emission surface of outer periphery side light guide, 8A, 18A... Ejection surface of center side light guide, 10, 110... Element substrate, 41A, 41B. 151, first surface portion, 52, 152, second surface portion, 421, polarization conversion device, 421A, incident surface, 431, liquid crystal panel (light modulation device), P1, P11, first reflection layer (reflection layer).

Claims (8)

A light source device comprising: a solid light source mounted on an element substrate and emitting light by applying a predetermined voltage; and a light guide member connected to the solid light source and guiding light incident from the solid light source. ,
The solid-state light source includes a first surface portion that is along the element substrate and opposite to the surface facing the element substrate, and a second surface portion that is orthogonal to the first surface portion of the solid-state light source. ,
The light guide member is disposed on the outermost periphery of the light guide member, and at least the second surface portion and one end of the solid light source are connected to a substantially cylindrical outer light guide portion;
A center-side light guide portion disposed inside the outer peripheral-side light guide portion and connected to at least the first surface portion and one end portion of the solid-state light source;
A reflective layer provided between the outer peripheral light guide and the center light guide;
A reflection surface is formed on the outer peripheral surface of the outer peripheral light guide unit,
The outer peripheral light guide part guides light incident from the one end part connected to at least the second surface part of the solid light source to the other end part side,
The center-side light guide part guides light incident from the one end part connected to at least the first surface part of the solid-state light source to the other end part side,
The end surfaces of the other end portions of the outer peripheral side light guide portion and the center side light guide portion are exit surfaces from which the guided light is emitted,
The light emitting device according to claim 1, wherein an emission surface of the outer peripheral side light guide unit and an emission surface of the center side light guide unit are both oriented in a predetermined direction. The light source device according to claim 1,
The outer peripheral surface of the outer peripheral light guide unit and the outer peripheral surface of the central light guide unit have curved surfaces that allow light emitted from the emission surface of each light guide unit to follow a predetermined direction. A light source device characterized by the above. The light source device according to claim 1,
The outer peripheral surface of the said outer peripheral side light guide part and the said center side light guide part has a planar shape, The light source device characterized by the above-mentioned. The light source device according to any one of claims 1 to 3,
The exit surface of the center-side light guide unit bulges in the light exit direction, and aligns the light emitted from the center-side light guide unit in the substantially normal direction of the exit surface of the light guide member as a whole. A light source device characterized by having an effect. The light source device according to any one of claims 1 to 4,
The area ratio between the exit surface of the outer periphery-side light guide unit and the exit surface of the center-side light guide unit is the ratio of the amount of light incident on the outer periphery-side light guide unit and the amount of light incident on the center-side light guide unit. And a light source device characterized by being substantially equal. The light source device according to claim 5,
The center-side light guide unit includes at least a first center light guide unit and a second center light guide unit, and is configured in a multilayer structure in which a reflective layer is interposed between the light guide units. The light source device is characterized in that the area ratio of the exit surfaces of the respective light guide units constituting the unit is substantially equal to the ratio of the amount of light incident on each light guide unit.   A light source device according to any one of claims 1 to 6, a light modulation device that modulates light emitted from the light source device according to image information, and a projection optical device that projects the modulated light. A projector characterized by comprising. The projector according to claim 7, wherein
A polarization conversion device that aligns the polarization direction of incident light is disposed downstream of the light path of the light source device,
The projector according to claim 1, wherein an exit surface of the light source device is formed to be substantially similar to an entrance surface of the polarization conversion device.

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