projector

Abstract

The present application provides a projector with less speckle noise. The projector of the present application is a projector that projects an image onto a projection target without focusing, and includes a first light source device, and a light modulation element that modulates light emitted from the first light source device. The first light source device includes a light emitting element that emits first light having a first wavelength band, a wavelength conversion member that includes a phosphor and converts the first light emitted from the light emitting element into second light having a second wavelength band, and an emission portion that is disposed along a central axis of the wavelength conversion member and emits the second light generated by the wavelength conversion member. The emission portion has a first end portion that opposes the wavelength conversion member, a second end portion that is located on an opposite side of the first end portion along the central axis, and a tapering portion whose cross-sectional area perpendicular to the central axis gradually decreases from the first end portion toward the second end portion. The tapering portion has a light emission surface that is inclined with respect to the central axis and emits the second light.

Description

Technical Field

[0001] This invention relates to projectors. Background Technology

[0002] In conventional projectors, for example, whenever the distance from the projector to the screen changes, it is necessary to adjust the focal length of the projection optics to focus the image. To address this, a projector has been proposed that eliminates the need for image focusing. As an example of such a projector, Patent Document 1 discloses a projector equipped with a transmissive spatial light modulator and a laser light source that emits a laser that illuminates the spatial light modulator.

[0003] Patent Document 1: International Publication No. 2017 / 145400

[0004] Patent Document 1 describes a projector in which the light beams emitted from each pixel of the spatial light modulator are formed by lasers and have high directivity. Therefore, even when the distance from the projector to the screen changes, image blurring due to defocusing will not occur. However, in the projector of Patent Document 1, due to the high coherence of the projected light, the light scattered on the screen interferes, generating speckle noise. Therefore, there are problems such as localized glare in the projected image and reduced display quality. Summary of the Invention

[0005] To address the aforementioned issues, one embodiment of the present invention provides a projector that projects images onto a target object without focusing. The projector includes: a first light source device; and a light modulation element that modulates light emitted from the first light source device. The first light source device includes: a light-emitting element that emits first light having a first wavelength band; a wavelength conversion member comprising a phosphor that converts the first light emitted from the light-emitting element into second light having a second wavelength band different from the first wavelength band; and an emission portion disposed along the central axis of the wavelength conversion member, emitting the second light generated by the wavelength conversion member. The emission portion has: a first end opposite to the wavelength conversion member; a second end located along the central axis on a side opposite to the first end; and a reduction portion whose cross-sectional area perpendicular to the central axis gradually decreases from the first end toward the second end. The reduction portion has a light emission surface inclined relative to the central axis, emitting the second light. Attached Figure Description

[0006] Figure 1 This is a schematic structural diagram of the projector according to the first embodiment.

[0007] Figure 2 This is a schematic structural diagram of the first light source device according to the first embodiment.

[0008] Figure 3 This is a three-dimensional view of the first light source device.

[0009] Figure 4A This is a graph showing the angular distribution of fluorescence when H / L = 1.2.

[0010] Figure 4B This is a graph showing the illuminance distribution of fluorescence when H / L = 1.2.

[0011] Figure 5A This is a graph showing the angular distribution of fluorescence when H / L = 1.3.

[0012] Figure 5B This is a graph showing the illuminance distribution of fluorescence when H / L = 1.3.

[0013] Figure 6A This is a graph showing the angular distribution of fluorescence when H / L = 1.4.

[0014] Figure 6B This is a graph showing the illuminance distribution of fluorescence when H / L = 1.4.

[0015] Figure 7A This is a graph showing the angular distribution of fluorescence when H / L = 1.5.

[0016] Figure 7B This is a graph showing the illuminance distribution of fluorescence when H / L = 1.5.

[0017] Figure 8A This is a graph showing the angular distribution of fluorescence when H / L = 1.6.

[0018] Figure 8B This is a graph showing the illuminance distribution of fluorescence when H / L = 1.6.

[0019] Figure 9A This is a graph showing the angular distribution of fluorescence when H / L = 1.7.

[0020] Figure 9B This is a graph showing the illuminance distribution of fluorescence when H / L = 1.7.

[0021] Figure 10A This is a graph showing the angular distribution of fluorescence when H / L = 1.8.

[0022] Figure 10B This is a graph showing the illuminance distribution of fluorescence when H / L = 1.8.

[0023] Figure 11 This is a schematic structural diagram of the projector according to the second embodiment.

[0024] Figure 12 This is a schematic structural diagram of the projector according to the third embodiment.

[0025] Figure 13 This is a schematic structural diagram of the projector according to the fourth embodiment.

[0026] Figure 14 This is a schematic structural diagram of the projector according to the fifth embodiment.

[0027] Figure 15 This is a schematic structural diagram of the projector according to the sixth embodiment.

[0028] Figure 16 This is a schematic structural diagram of the projector according to the seventh embodiment.

[0029] Label Explanation

[0030] 10, 12, 13, 14, 15, 16, 17: Projector; 20, 23: First light source device; 22: Second light source device; 24: Third light source device; 30: Optical modulation element; 30R, 30Y: First optical modulation element; 30B: Second optical modulation element; 30G: Third optical modulation element; 40: Angle conversion lens; 50, 61, 66, 67: Wavelength conversion component; 50a: First surface; 50b: Second surface; 50c: Third surface; 54, 62: Emission section; 54a: First end; 5 4b: Second end; 54c: Decreasing portion; 54d: Light emitting surface; 56, 57: Light-emitting elements; 60, 64: Light-combining elements; J: Central axis; E: Excitation light (first light); Y, R: Fluorescence (second light); B: Fluorescence (third light); G: Fluorescence (fourth light); R1: Red modulation light (first modulation light); B1: Blue modulation light (second modulation light); G1: Green modulation light (third modulation light); Y1: Yellow modulation light (first modulation light); W: Composite light (first composite light, second composite light). Detailed Implementation

[0031] [First Implementation]

[0032] Hereinafter, the first embodiment of the present invention will be described with reference to the accompanying drawings.

[0033] The projector in this embodiment is an example of a projector that uses a liquid crystal panel as a light modulation element.

[0034] In the following figures, the scales of the dimensions are sometimes shown differently depending on the constituent elements in order to facilitate observation of the constituent elements.

[0035] Figure 1 This is a diagram showing the schematic structure of the projector 10 in this embodiment.

[0036] like Figure 1 As shown, the projector 10 of this embodiment includes a first light source device 20, a light modulation element 30, and an angle conversion lens 40. The projector 10 projects any image onto the object being projected in a focus-free manner. The object being projected is the medium on which the image generated by the projector 10 is projected, such as a screen, wall, glass, table, building, water droplets, or a collection of powder particles. Furthermore, the image includes, for example, characters, drawings, symbols, patterns, 2D barcodes, and other encoded patterns.

[0037] In this specification, a projector without focus refers to a projector that does not have an imaging optical system for imaging the image of the light modulation element onto the projected object. For example, it refers to a projector that does not require focusing even when the distance from the projector to the screen changes. In the projector 10 of this embodiment, as described later, since it has a first light source device 20 that emits phosphor Y from a very small emission section 54, the light from the multiple pixels of the light modulation element 30 does not mix with each other, and a focused image can be projected onto the projected object without using an imaging optical system.

[0038] Hereinafter, the XYZ orthogonal coordinate system will be used for explanation in the accompanying drawings as needed. The X-axis is an axis parallel to the optical axis AX1 of the first light source device 20. The optical axis AX1 of the first light source device 20 is the central axis of the fluorescence Y emitted from the first light source device 20. The Y-axis is an axis along the direction in which the wavelength conversion member 50 and the light source section 51 are arranged. The Z-axis is an axis orthogonal to the X-axis and Y-axis.

[0039] Figure 2 This is a schematic structural diagram of the first light source device 20 according to the first embodiment. Figure 3 This is a three-dimensional view of the first light source device 20.

[0040] like Figure 2 As shown, the first light source device 20 includes a wavelength conversion member 50, a light source section 51, a reflection member 53, and an emission section 54. Furthermore, the light source section 51 includes a substrate 55 and a light-emitting element 56. Additionally, the first light source device 20 may also include a support member for supporting the wavelength conversion member 50, etc.

[0041] The wavelength conversion component 50 has a quadrangular prism shape extending in the X-axis direction and has six faces. The side of the wavelength conversion component 50 extending in the X-axis direction is longer than the sides extending in the Y-axis direction and the Z-axis direction. Therefore, the X-axis direction corresponds to the length direction of the wavelength conversion component 50. The length of the side extending in the Y-axis direction is equal to the length of the side extending in the Z-axis direction. In other words, the cross-sectional shape of the wavelength conversion component 50 cut by a face perpendicular to the X-axis direction (YZ plane) is rectangular. That is, the cross-sectional shape of the wavelength conversion component 50 cut by a face perpendicular to the X-axis direction can be either square or rectangular.

[0042] The wavelength conversion component 50 has: a first surface 50a, which intersects the longitudinal direction (X-axis direction) of the wavelength conversion component 50 and is provided with an emission portion 54; a second surface 50b, which intersects the longitudinal direction (X-axis direction) of the wavelength conversion component 50 and is located on the opposite side to the first surface 50a; a third surface 50c and a fourth surface 50d, which intersect the first surface 50a and the second surface 50b and are located on opposite sides; and a fifth surface and a sixth surface (not shown), which intersect the third surface 50c and the fourth surface 50d and are located on opposite sides. In the following description, the four surfaces, the third surface 50c, the fourth surface 50d, the fifth surface, and the sixth surface, are collectively referred to as side surface 50g.

[0043] The axis passing through the center of the first surface 50a and the center of the second surface 50b of the wavelength conversion component 50 and parallel to the X-axis is defined as the central axis J of the wavelength conversion component 50. The central axis J of the wavelength conversion component 50 coincides with the optical axis AX1 of the first light source device 20.

[0044] In this embodiment, as described later, the wavelength conversion component 50 and the emission portion 54 are integrally formed. Therefore, the first surface 50a among the six surfaces is not an actual surface, but is defined as an imaginary surface defining the boundary with the emission portion 54. The wavelength conversion component 50 is preferably a quadrangular prism shape, but it may not necessarily have a quadrangular prism shape; for example, it may have a triangular prism shape, a cylindrical shape, etc. When the wavelength conversion component 50 is triangular prism in shape, the three surfaces intersecting the first surface and the second surface are collectively referred to as the side surface 50g. When the wavelength conversion component 50 is cylindrical in shape, the continuous curved surface intersecting the first surface and the second surface is referred to as the side surface 50g.

[0045] The wavelength conversion component 50 includes at least a phosphor that converts excitation light (first light) E having a first wavelength band into fluorescence Y having a second wavelength band different from the first wavelength band. In this embodiment, the excitation light E emitted from the light-emitting element 56 (described later) is incident on the third surface 50c. After being guided inside the wavelength conversion component 50, the fluorescence Y is emitted from the first surface 50a toward the emission portion 54 and then emitted to the outside from the emission portion 54.

[0046] The wavelength conversion component 50 includes a ceramic phosphor composed of a polycrystalline phosphor that converts the wavelength of the excitation light E into fluorescence Y. The second band of fluorescence Y is, for example, the yellow band of 490 nm to 750 nm. That is, fluorescence Y is a yellow fluorescence containing both red and green light components.

[0047] The wavelength conversion component 50 may also comprise a single-crystal phosphor instead of a polycrystalline phosphor. Alternatively, the wavelength conversion component 50 may be made of fluorescent glass. Alternatively, the wavelength conversion component 50 may be made of a material in which a large number of phosphor particles are dispersed in a binder made of glass or resin. The wavelength conversion component 50 made of such a material converts the excitation light E into fluorescence Y having a second wavelength band.

[0048] Specifically, the material of the wavelength conversion component 50 may include, for example, a yttrium aluminum garnet (YAG) phosphor. Taking YAG:Ce containing cerium (Ce) as an activator as an example, materials used as the material of the wavelength conversion component 50 may include materials obtained by mixing raw material powders containing constituent elements such as Y2O3, Al2O3, and CeO3 and carrying out a solid-phase reaction; Y-Al-O amorphous particles obtained by wet methods such as co-precipitation and sol-gel methods; and YAG particles obtained by gas-phase methods such as spray drying, flame thermal decomposition, and thermal plasma methods.

[0049] The light source unit 51 includes a light-emitting element 56 having a light-emitting surface 56a that emits excitation light E in the first wavelength band. The light source unit 51 is disposed opposite to the third surface 50c of the wavelength conversion member 50. The light-emitting element 56 is, for example, a light-emitting diode (LED). Thus, the light source unit 51 is disposed opposite to a portion of the side surface 50g of the wavelength conversion member 50 along its length direction. Furthermore, the number and arrangement of the light source units 51 are not particularly limited. The light-emitting surface 56a of the light-emitting element 56 is disposed opposite to the third surface 50c of the wavelength conversion member 50, and emits excitation light E toward the third surface 50c. The first wavelength band is, for example, a violet to blue band from 400nm to 480nm, with a peak wavelength of, for example, 445nm.

[0050] The substrate 55 supports the light-emitting elements 56. A plurality of light-emitting elements 56 are disposed on one side 55a of the substrate 55. In this embodiment, the light source unit 51 is composed of the light-emitting elements 56 and the substrate 55; however, it may also include other optical components such as a light guide plate, a diffuser plate, and a lens. Furthermore, the number of light-emitting elements 56 disposed on the substrate 55 is not particularly limited.

[0051] The reflective component 53 is disposed opposite to the second surface 50b of the wavelength conversion component 50. The reflective component 53 reflects the phosphor Y that is guided inside the wavelength conversion component 50 and reaches the second surface 50b. The reflective component 53 is a component different from the wavelength conversion component 50, for example, it is a plate-shaped component made of a metal material such as aluminum. The reflective component 53 has a reflective surface 53r that is opposite to the second surface 50b of the wavelength conversion component 50 and reflects the phosphor Y. The reflective surface 53r can be the surface of the metal material itself, or it can be made of a metal film or a dielectric multilayer film formed on the surface of the metal material.

[0052] In the first light source device 20, when excitation light E emitted from the light-emitting element 56 is incident on the wavelength conversion member 50, the phosphor contained inside the wavelength conversion member 50 is excited and emits fluorescence Y from any light-emitting point. The fluorescence Y travels in all directions from any light-emitting point, but the fluorescence Y traveling towards the side 50g undergoes repeated total internal reflection at multiple locations on the side 50g and travels towards either the first surface 50a or the second surface 50b. The fluorescence Y traveling towards the first surface 50a is incident on the emission section 54. On the other hand, the fluorescence Y traveling towards the second surface 50b is reflected by the reflecting member 53 and then travels towards the first surface 50a.

[0053] A portion of the excitation light E incident on the wavelength conversion member 50 that is not used to excite the phosphor is reflected by components surrounding the wavelength conversion member 50, including the light-emitting element 56 of the light source section 51, or by a reflective component 53 disposed on the second surface 50b. Therefore, a portion of the excitation light E is enclosed inside the wavelength conversion member 50 and reused.

[0054] The emission section 54 is disposed along the central axis J of the wavelength conversion member 50. The emission section 54 emits the fluorescence Y generated by the wavelength conversion member 50. In this embodiment, the wavelength conversion member 50 and the emission section 54 are constituted as a single component. Therefore, the emission section 54, like the wavelength conversion member 50, contains a YAG-based phosphor.

[0055] The emission portion 54 has a first end portion 54a, a second end portion 54b, and a reduction portion 54c. The first end portion 54a faces the first surface 50a of the wavelength conversion member 50. The second end portion 54b is located on the opposite side of the first end portion 54a along the central axis J. The reduction portion 54c is a portion with a cross-sectional area perpendicular to the central axis J that gradually decreases from the first end portion 54a toward the second end portion 54b. The reduction portion 54c has a light emission surface 54d that is inclined relative to the central axis J and emits fluorescence Y. In this embodiment, the entire portion between the first end portion 54a and the second end portion 54b is the reduction portion 54c. This structure is preferred, but it is acceptable as long as at least a portion between the first end portion 54a and the second end portion 54b is the reduction portion 54c.

[0056] like Figure 3 As shown, in this embodiment, the ejection portion 54 is shaped like a quadrangular pyramid. Therefore, the ejection portion 54 has four light-emitting surfaces 54d. Each light-emitting surface 54d has a triangular shape with one side connected to each side 50g of the wavelength conversion member 50. Viewed from a direction parallel to the central axis J, the first end portion 54a has a square shape. The second end portion 54b has a pointed shape where the vertices of the four light-emitting surfaces 54d make point contact. The ejection portion 54 is formed, for example, by grinding the ends of the quadrangular prism-shaped wavelength conversion member 50 to create a quadrangular pyramid shape.

[0057] In a light source device without such an emission section, the first surface of the wavelength conversion component becomes the light emission surface, from which fluorescence is emitted. However, in this structure, a relatively large proportion of the fluorescence reaching the first surface is incident at an angle of incidence greater than the critical angle. This fluorescence undergoes total internal reflection at the first surface and is not extracted to the outside. Therefore, in a light source device without an emission section, it is difficult to improve the fluorescence extraction efficiency.

[0058] In contrast, in this embodiment, since the light emitting surface 54d of the emission section 54 is inclined relative to the central axis J, the proportion of fluorescence Y incident at an angle of incidence less than the critical angle increases compared to the case without an emission section. Furthermore, even if the initial incident angle at the light emitting surface 54d is greater than the critical angle after fluorescence Y incident on the emission section 54, the direction of fluorescence Y changes after total internal reflection at the light emitting surface 54d. Therefore, at subsequent incident moments at the light emitting surface 54d, a certain proportion of fluorescence Y with an incident angle less than the critical angle is generated. That is, whenever total internal reflection occurs repeatedly at the light emitting surface 54d, the amount of fluorescence Y with an incident angle less than the critical angle increases. Therefore, according to this embodiment, the extraction efficiency of fluorescence Y can be improved compared to the case without an emission section.

[0059] like Figure 1 As shown, the light modulation element 30 modulates the phosphor Y emitted from the first light source device 20 according to image information. In this embodiment, a transmissive liquid crystal panel is used as the light modulation element 30. The liquid crystal panel has a structure having multiple pixels arranged in a matrix, and the light transmittance can be adjusted for each pixel. The effective modulation area of ​​the liquid crystal panel is rectangular in shape. The effective modulation area is the area of ​​the liquid crystal panel excluding the border portion, which does not contribute to the display, and is the area having multiple pixels and substantially forming an image. The shape of the effective modulation area can be square, or it can be a rectangle with an aspect ratio of 4:3, 16:9, etc. In addition, transmissive liquid crystal panels have a general structure and are known, so detailed description is omitted.

[0060] Polarizing plates that allow predetermined linearly polarized light to pass through are provided on both the light incident side and the light emitting side of the liquid crystal panel. The light modulation element 30 may or may not have a color filter. When the light modulation element 30 has a color filter, the projector 10 can project multi-color images. When the light modulation element 30 does not have a color filter, the projector 10 can project monochromatic images.

[0061] An angle-conversion lens 40 is disposed between the first light source device 20 and the light modulation element 30, allowing the fluorescence Y emitted from the emission section 54 to pass through. The angle-conversion lens 40 refracts the fluorescence Y emitted from the emission section 54 at a large emission angle towards the side where the emission angle decreases. That is, the emission angle of the fluorescence Y emitted from the angle-conversion lens 40 is smaller than the emission angle of the fluorescence Y incident on the angle-conversion lens 40. The angle-conversion lens 40 is constructed of a convex lens with positive diopter. In this embodiment, the angle-conversion lens 40 does not parallelize the fluorescence Y, but it may also be a collimating lens that parallelizes the fluorescence Y. Alternatively, the angle-conversion lens 40 may also be constructed of an aspherical lens.

[0062] [Relationship between the shape of the emission section and the illuminance distribution of fluorescence]

[0063] In order to investigate the change in the illuminance distribution of fluorescence Y when the shape of the emission section 54, i.e., the shape of a square pyramid, is changed, the inventors conducted the simulation shown below.

[0064] Specifically, such as Figure 3 As shown, with the length of the emission portion 54 along the central axis J (X-axis direction), i.e., the height of the quadrangular pyramid, denoted as H, and the length of the first end portion 54a in the direction perpendicular to the central axis J (Y-axis direction and Z-axis direction), i.e., the length of one side of the square forming the base of the quadrangular pyramid, denoted as L, the inventors conducted a simulation by varying the dimension ratio H / L. If the dimension ratio H / L is varied, the tilt angle of the light emission surface 54d of the emission portion 54 relative to the central axis J changes, thus altering the emission angle distribution and illuminance distribution of the fluorescence Y.

[0065] As simulation conditions, a sample with a length of 50 mm from the second surface 50b of the wavelength conversion component 50 to the second end 54b of the emission portion 54 was used, formed by an integral YAG:Ce phosphor rod of wavelength conversion component 50 and emission portion 54. The size ratio H / L of the emission portion 54 was varied to seven different values: 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, and 1.8. As evaluation criteria, the angular distribution of the fluorescence Y emitted from the emission portion 54 and the illuminance distribution on an imaginary plane set at a position 50 mm away from the second end 54b were evaluated.

[0066] Figure 4A and Figure 4BThis indicates the result of a size ratio H / L = 1.2. Figure 5A and Figure 5B This indicates a size ratio H / L = 1.3. Figure 6A and Figure 6B This indicates a size ratio H / L = 1.4. Figure 7A and Figure 7B This indicates the result of a size ratio H / L = 1.5. Figure 8A and Figure 8B This indicates a size ratio H / L = 1.6. Figure 9A and Figure 9B This indicates a size ratio H / L = 1.7. Figure 10A and Figure 10B This indicates the result for a size ratio H / L = 1.8. In these figures, figures ending in A represent the angular distribution of radiation, and figures ending in B represent the illuminance distribution.

[0067] Figure 4A , Figure 5A , Figure 6A , Figure 7A , Figure 8A , Figure 9A as well as Figure 10A The solid line shown is from Figure 2 The graphs show the angular distribution of fluorescence Y when viewed from the +Z axis towards the -Z axis (when viewed from the emission side along the central axis J) when viewed from the -X axis towards the +X axis. The 90° polar angles shown in these graphs correspond to the direction along the central axis J of the wavelength conversion unit 50. The values ​​on the horizontal axis of these graphs are in units of radiometric intensity (mW / sr), a physical quantity representing the radiometric energy emitted per unit time from the radioactive source in a specified direction. Furthermore, the absolute values ​​of the horizontal axis are relative indicators without particular significance.

[0068] exist Figure 4B , Figure 5B , Figure 6B , Figure 7B , Figure 8B , Figure 9B as well as Figure 10B In, it means from Figure 2 The illuminance distribution on the YZ plane at a position 50 mm away from the second end 54b of the emission section 54 when viewed from the -X-axis toward the +X-axis direction (when viewed toward the emission side along the central axis J). A graph showing the illuminance distribution along the Y-axis is shown to the right of the illuminance distribution shown in the upper left of each graph, and a graph showing the illuminance distribution along the Z-axis is shown below the illuminance distribution. In each graph, the horizontal axis represents the coordinates on each axis (Y coordinate, Z coordinate), and the vertical axis represents the illuminance. The values ​​of the horizontal and vertical axes are relative values.

[0069] like Figure 4A as well as Figure 4B As shown, with a size ratio H / L = 1.2, the radiation intensity in the region near the central axis J is higher than that in the region far from the central axis J, resulting in a sharp peak in the illuminance distribution near the central axis J. Therefore, although the illuminance is higher near the central axis J, it tends to decrease sharply in locations far from the central axis J.

[0070] In contrast, such as Figure 5A as well as Figure 5B As shown, when the size ratio H / L = 1.3, the radiated energy in the region near the central axis J is dispersed to the region away from the central axis J. Therefore, compared to the case where the size ratio H / L = 1.2, the illuminance distribution in the region near the central axis J exhibits a flat shape. Thus, from the region near the central axis J to the periphery of the approximately square region, an illuminance exceeding a predetermined value can be obtained. Therefore, for example, when illuminating a light modulation element having a rectangular effective modulation region using this light source device, an image bright up to all four corners of the effective modulation region can be obtained. Furthermore, as... Figure 6A as well as Figure 6B As shown in the following figures, even when the size ratio H / L is increased from 1.4 to 1.8, the same effect as when the size ratio H / L = 1.3 can be obtained.

[0071] Furthermore, although not shown in the simulation, the upper limit of the size ratio H / L is preferably around 3.0. The reason is that if the size ratio H / L exceeds 3.0, the emitted area increases, the apparent size of the light source becomes larger, resulting in light mixing from adjacent pixels and a decrease in resolution. Additionally, in terms of manufacturing, the end portion becomes thinner and more prone to breakage.

[0072] [Effects of the first embodiment]

[0073] The projector 10 of this embodiment includes a first light source device 20 and a light modulation element 30 that modulates the fluorescence Y emitted from the first light source device 20. The first light source device 20 includes: a light-emitting element 56 that emits excitation light E; a wavelength conversion member 50 that includes a phosphor and converts the excitation light E emitted from the light-emitting element 56 into fluorescence Y; and an emission portion 54 disposed along the central axis J of the wavelength conversion member 50, emitting the fluorescence Y generated by the wavelength conversion member 50. The emission portion 54 includes: a first end portion 54a opposite to the wavelength conversion member 50; a second end portion 54b located on the side opposite to the first end portion 54a along the central axis J; and a decreasing portion 54c whose cross-sectional area perpendicular to the central axis J gradually decreases from the first end portion 54a toward the second end portion 54b. The decreasing portion 54c has a light emission surface 54d inclined relative to the central axis J and emitting fluorescence Y.

[0074] According to the projector 10 of this embodiment, the fluorescence Y generated in the first light source device 20 illuminates the light modulation element 30. Therefore, the fluorescence Y emitted from the light modulation element 30 has sufficiently low coherence compared to laser light. Thus, compared to the case of laser light, there is less interference of the light scattered on the projected object, resulting in an image with less speckle noise. Furthermore, since the fluorescence Y is emitted from the emission section 54 with the above structure, the light-emitting portion of the first light source device 20 is close to a point light source. Therefore, the light from the multiple pixels of the light modulation element 30 does not mix with each other, eliminating the need for an imaging optical system. Thus, a focusless projector 10 capable of projecting a clear image onto the projected object can be realized.

[0075] In the projector 10 of this embodiment, the wavelength conversion member 50 has a first surface 50a and a second surface 50b located on opposite sides of each other in the longitudinal direction of the wavelength conversion member 50, and a third surface 50c intersecting the first surface 50a and the second surface 50b. Fluorescent Y is emitted from the first surface 50a toward the emission portion 54, and excitation light E emitted from the light-emitting element 56 is incident on the third surface 50c.

[0076] According to this structure, fluorescence Y can be emitted from the emission portion 54, which is sufficiently small in length relative to the wavelength conversion component 50, and the third surface 50c into which the excitation light E is incident can be wider. Therefore, a first light source device with high efficiency, compact structure and close to a point light source can be realized.

[0077] In the projector 10 of this embodiment, the first surface 50a of the wavelength conversion component 50 is rectangular, and the effective modulation area of ​​the light modulation element 30 is rectangular.

[0078] According to this structure, since the illumination area of ​​the fluorescence Y emitted from the first light source device 20 is rectangular, it is possible to efficiently illuminate all four corners of the effective modulation area of ​​the light modulation element 30.

[0079] In the projector 10 of this embodiment, the shape of the emission section 54 is a square pyramid.

[0080] Based on this structure, a fluorescent Y with a rectangular illuminance distribution can be obtained. Furthermore, an emission portion 54 can be easily formed at the end of the prism-shaped wavelength conversion component 50.

[0081] In the projector 10 of this embodiment, the size ratio H / L of the emission section 54 is 1.3 or more.

[0082] Based on this structure, by appropriately setting the size ratio H / L of the emission section 54, as described above, a projector 10 with less illuminance unevenness and capable of projecting bright images to all four corners of the projected surface can be realized.

[0083] In the projector 10 of this embodiment, the wavelength conversion component 50 and the emission unit 54 are composed of an integral component.

[0084] According to this structure, the emission section 54 can be easily formed in the manufacturing process of the first light source device 20 using methods such as phosphor polishing. Furthermore, since the emission section 54 also contains a phosphor, the excitation light E incident on the emission section 54 is converted into fluorescence Y. Therefore, compared to the case where the emission section does not contain a phosphor, the amount of fluorescence Y can be increased. Additionally, since there is no interface between the wavelength conversion member 50 and the emission section 54, the loss of fluorescence Y when passing through the interface can be eliminated.

[0085] Furthermore, if the amount of fluorescent Y extracted from the emission section 54 is not too large, the emission section 54 can also be composed of a light-transmitting component separate from the wavelength conversion component 50, and joined to the wavelength conversion component 50. According to this structure, the emission section 54 can be manufactured separately from the wavelength conversion component 50 by means of stamping or other methods using a mold, thus eliminating the need for grinding the phosphor.

[0086] The projector 10 of this embodiment also includes an angle conversion lens 40 that allows the fluorescence Y emitted from the emission section 54 to pass through. The emission angle of the fluorescence Y emitted from the angle conversion lens 40 is smaller than the emission angle of the fluorescence Y incident on the angle conversion lens 40.

[0087] According to this structure, the diffusion of fluorescence Y emitted from the first light source device 20 can be suppressed, and a bright image can be projected to a greater distance.

[0088] In the projector 10 of this embodiment, the angle conversion lens 40 is disposed between the first light source device 20 and the light modulation element 30.

[0089] According to this structure, fluorescent Y with a small emission angle can be incident on the light modulation element 30, resulting in a clearer image.

[0090] In the projector 10 of this embodiment, the angle conversion lens 40 may also be composed of an aspherical lens.

[0091] According to this structure, it is possible to suppress the blurring of the image caused by the mixing of light emitted from each pixel due to the spherical aberration of the angle conversion lens 40.

[0092] In the projector 10 of this embodiment, the light modulation element 30 is composed of a transmissive liquid crystal panel.

[0093] Based on this structure, a liquid crystal projector capable of projecting bright images can be realized.

[0094] [Second Implementation]

[0095] The following uses Figure 11 The second embodiment of the present invention will be described.

[0096] The basic structure of each light source device in the projector of the second embodiment is the same as that in the first embodiment, so the description of the basic structure of the light source device is omitted.

[0097] Figure 11 This is a schematic structural diagram of the projector 12 according to the second embodiment.

[0098] exist Figure 11 In this document, the same reference numerals are used for the same constituent elements as those used in the first embodiment, and the descriptions are omitted.

[0099] like Figure 11 As shown, the projector 12 of this embodiment includes a first light source device 20, a second light source device 22, a light combining element 60, a light modulation element 30, and an angle conversion lens 40.

[0100] The second light source device 22 includes a wavelength conversion component 61, a light source section 52, a reflection component 53, and an emission section 62. The basic structure of the second light source device 22 is the same as that of the first light source device 20, but the type of phosphor included in the wavelength conversion component 61 is different from that in the wavelength conversion component 50 of the first light source device 20. The second light source device 22 emits blue fluorescence B (third light) having a third band that is different from the first band of the excitation light E and the second band of the fluorescence Y.

[0101] The wavelength conversion component 61 is, for example, made of fluorescent glass in which rare earth ions are dispersed in glass, or a material in which a blue phosphor is dispersed in a binder such as glass or resin. Specifically, as the fluorescent glass, LUMILAS (trade name, manufactured by Sumida Optical Glass Co., Ltd.) is used. As the blue phosphor, BaMgAl is used, for example. 10 O 17 Eu(II), etc. The wavelength conversion unit 61 converts the excitation light emitted from the light-emitting element 57 into fluorescence B in the blue band, for example, 450 nm to 495 nm. The light-emitting element 57 of the second light source device 22 is a light-emitting element that emits excitation light in the ultraviolet or violet band.

[0102] The light combining element 60 is positioned at the intersection of the optical axis AX1 of the first light source device 20 and the optical axis AX2 of the second light source device 22. The light combining element 60 is composed of a dichroic mirror that reflects blue light and transmits yellow light. The light combining element 60 combines the yellow fluorescence Y emitted from the first light source device 20 and the blue fluorescence B emitted from the second light source device 22, and emits white composite light (first composite light) W along the optical axis AX1.

[0103] A light modulation element 30 is disposed on the emission side of the light combining element 60. An angle conversion lens 40 is disposed between the light combining element 60 and the light modulation element 30. Similar to the first embodiment, the light modulation element 30 is constructed from a transmissive liquid crystal panel. The light modulation element 30 modulates the white composite light W emitted from the light combining element 60 according to image information. The light modulation element 30 may or may not have a color filter. When the light modulation element 30 has a color filter, the projector 12 can project a color image. When the light modulation element 30 does not have a color filter, the projector 12 can project a monochrome image.

[0104] [Effects of the second implementation method]

[0105] In this embodiment, the same effect as in the first embodiment can also be obtained, such as a focusless projector 12 that can project images with less speckle noise.

[0106] The projector 12 of this embodiment further includes: a second light source device 22 that emits fluorescence B having a third wavelength; and a light combining element 60 that combines fluorescence Y emitted from the first light source device 20 and fluorescence B emitted from the second light source device 22 to emit combined light W. A light modulation element 30 modulates the combined light W emitted from the light combining element 60.

[0107] According to this structure, an image can be formed using white composite light W obtained by combining fluorescence Y emitted from the first light source device 20 and fluorescence B emitted from the second light source device 22. Therefore, compared to the projector 10 of the first embodiment which only uses fluorescence Y emitted from the first light source device 20, the color reproduction of the image can be improved.

[0108] [Third Implementation]

[0109] The following uses Figure 12 The third embodiment of the present invention will be described.

[0110] The basic structure of each light source device in the projector of the third embodiment is the same as that in the first embodiment, so the description of the basic structure of the light source device is omitted.

[0111] Figure 12 This is a schematic structural diagram of the projector 13 according to the third embodiment.

[0112] exist Figure 12 In this document, the same reference numerals are used for the same components as those used in the previous embodiments, and descriptions are omitted.

[0113] like Figure 12As shown, the projector 13 of this embodiment includes a first light source device 23, a second light source device 22, a third light source device 24, a light combining element 64, a light modulation element 30, and an angle conversion lens 40.

[0114] The first light source device 23, the second light source device 22, and the third light source device 24 have the same basic structure, but the types of phosphors included in each wavelength conversion component are different from those in the first light source device. The first light source device 23 emits red fluorescence R with a second wavelength band different from the first wavelength band of the excitation light. The second light source device 22 emits blue fluorescence B with a third wavelength band different from the first wavelength band of the excitation light and the second wavelength band of the fluorescence R. The third light source device 24 emits green fluorescence G (fourth light) with a fourth wavelength band different from the first wavelength band of the excitation light, the second wavelength band of the fluorescence R, and the third wavelength band of the fluorescence B.

[0115] Furthermore, the second light source device 22 in this embodiment is the same as the second light source device 22 in the second embodiment, so the description is omitted.

[0116] In the first light source device 23, the wavelength conversion component 66 includes, for example, a component containing any one of Pr, Eu, and Cr as an activator, made of Y. 1-x Gd x )3(Al,Ga)5O 12 A YAG-based phosphor (any one of Pr:YAG, Eu:YAG, or Cr:YAG) is used as the phosphor. Additionally, the activator may include one selected from Pr, Eu, and Cr, or it may be a co-activator containing multiple selected from Pr, Eu, and Cr. The wavelength conversion unit 66 converts the excitation light emitted from the light-emitting element 56 into fluorescence R in the red band, for example, 600 nm to 800 nm. The light-emitting element 56 of the first light source device 23 emits excitation light in the ultraviolet, violet, or blue bands.

[0117] In the third light source device 24, the wavelength conversion component 67 includes, for example, Lu3Al5O 12 Ce 3+ System phosphor, Y3O4:Eu 2+ System phosphor, (Ba,Sr)2SiO4:Eu 2+ Phosphor, Ba3Si6O 12 N2: Eu 2+ System phosphor, (Si,Al)6(O,N)8:Eu 2+The phosphor is a phosphor material such as a phosphor. The wavelength conversion unit 67 converts the excitation light emitted from the light-emitting element 56 into fluorescence G in the green band, for example, 500 nm to 570 nm. The light-emitting element 56 of the third light source device 24 emits excitation light in the ultraviolet band, violet band, or blue band.

[0118] A light-combining element 64 is positioned at the intersection of the optical axes AX1 of the first light source device 23, AX2 of the second light source device 22, and AX3 of the third light source device 24. The light-combining element 64 has a first dichroic mirror 641 and a second dichroic mirror 642. The first dichroic mirror 641 reflects blue light while allowing light of other wavelengths to pass through. The second dichroic mirror 642 reflects red light while allowing light of other wavelengths to pass through. According to this structure, the light-combining element 64 combines red fluorescence R emitted from the first light source device 23, blue fluorescence B emitted from the second light source device 22, and green fluorescence G emitted from the third light source device 24, emitting white composite light (second composite light) W along the optical axis AX3.

[0119] A light modulation element 30 is disposed on the emission side of a light combining element 64. An angle conversion lens 40 is disposed between the light combining element 64 and the light modulation element 30. Similar to the first embodiment, the light modulation element 30 is constructed from a transmissive liquid crystal panel. The light modulation element 30 modulates the white composite light W emitted from the light combining element 64 according to image information.

[0120] The light modulation element 30 may or may not have a color filter. When the light modulation element 30 has a color filter, the projector 13 can project a color image. When the light modulation element 30 does not have a color filter, the projector 13 can project a monochrome image. Alternatively, in a configuration where the light modulation element 30 does not have a color filter, the first light source device 23, the second light source device 22, and the third light source device 24 can be sequentially illuminated at different times, and the light modulation element 30 can be driven to sequentially form an image for red light, an image for blue light, and an image for green light in sync with the illumination timing of each light source device. With this configuration, the projector 13 can project a color image.

[0121] [Effects of the third embodiment]

[0122] In this embodiment, the same effect as in the first embodiment can also be achieved, such as a focusless projector 13 that can project images with less speckle noise.

[0123] The projector 13 of this embodiment includes: a first light source device 23 that emits red-band fluorescence R; a second light source device 22 that emits blue-band fluorescence B; and a third light source device 24 that emits green-band fluorescence G. A light combining element 64 combines the fluorescence R emitted from the first light source device 23, the fluorescence B emitted from the second light source device 22, and the fluorescence G emitted from the third light source device 24 to emit white composite light W. A light modulation element 30 modulates the composite light W emitted from the light combining element 64.

[0124] According to this structure, an image can be formed using white composite light W obtained by synthesizing the fluorescence R emitted from the first light source device 23, the fluorescence B emitted from the second light source device 22, and the fluorescence G emitted from the third light source device 24. Therefore, compared to the projector of the first embodiment that only uses the fluorescence Y emitted from the first light source device, the color reproduction of the image can be improved. Furthermore, since only one light modulation element is needed, the structure of the projector 13 can be simplified.

[0125] In the projector 13 of this embodiment, if the light modulation element 30 has a color filter structure, a color image can be projected. According to this structure, unlike the method of driving each light source device and light modulation element sequentially in time, a liquid crystal panel with a high-speed response is not required, thus simplifying the design of the light modulation element 30.

[0126] Alternatively, in the projector 13 of this embodiment, if the first light source device 23, the second light source device 22, and the third light source device 24 are lit sequentially according to time, and the light modulation element 30 is driven synchronously with the lighting timing of each light source device, then a color image can be projected. According to this structure, the light modulation element 30 does not need to have a color filter, and the number of pixels increases compared to the color filter method, thus enabling the acquisition of a bright image with high resolution.

[0127] [Fourth Implementation]

[0128] The following uses Figure 13 The fourth embodiment of the present invention will be described.

[0129] The basic structure of each light source device in the projector of the fourth embodiment is the same as that in the first embodiment, so the description of the basic structure of the light source device is omitted.

[0130] Figure 13 This is a schematic structural diagram of the projector 14 according to the fourth embodiment.

[0131] exist Figure 13 In this document, the same reference numerals are used for the same components as those used in the previous embodiments, and descriptions are omitted.

[0132] like Figure 13 As shown, the projector 14 of this embodiment includes a first light source device 23, a second light source device 22, a third light source device 24, a first light modulation element 30R, a second light modulation element 30B, a third light modulation element 30G, a light combining element 64, and an angle conversion lens 40. The first light source device 23, the second light source device 22, and the third light source device 24 are the same as those in the third embodiment.

[0133] A first optical modulation element 30R is disposed on the light-emitting side of the first light source device 23. The first optical modulation element 30R modulates the red fluorescence R emitted from the first light source device 23 according to image information, emitting red modulated light R1 as the first modulated light. A second optical modulation element 30B is disposed on the light-emitting side of the second light source device 22. The second optical modulation element 30B modulates the blue fluorescence B emitted from the second light source device 22 according to image information, emitting blue modulated light B1 as the second modulated light. A third optical modulation element 30G is disposed on the light-emitting side of the third light source device 24. The third optical modulation element 30G modulates the green fluorescence G emitted from the third light source device 24 according to image information, emitting green modulated light G1 as the third modulated light.

[0134] The first optical modulation element 30R, the second optical modulation element 30B, and the third optical modulation element 30G are each composed of a transmissive liquid crystal panel. The liquid crystal panel does not have a color filter.

[0135] The light combining element 64 has the same structure as the light combining element 64 in the third embodiment, but differs from the third embodiment in that it combines the modulated light modulated by each light modulating element. That is, the light combining element 64 combines the red modulated light R1 emitted from the first light modulating element 30R, the blue modulated light B1 emitted from the second light modulating element 30B, and the green modulated light G1 emitted from the third light modulating element 30G.

[0136] An angle conversion lens 40 is provided between the first light source device 23 and the first optical modulation element 30R. An angle conversion lens 40 is provided between the second light source device 22 and the second optical modulation element 30B. An angle conversion lens 40 is provided between the third light source device 24 and the third optical modulation element 30G.

[0137] [Effects of the fourth implementation method]

[0138] In this embodiment, the same effect as in the first embodiment can also be achieved, such as a focusless projector 14 that can project images with less speckle noise.

[0139] The projector 14 of this embodiment includes: a first light source device 23 that emits red-band fluorescence R; a second light source device 22 that emits blue-band fluorescence B; a third light source device 24 that emits green-band fluorescence G; a first light modulation element 30R that modulates the fluorescence R emitted from the first light source device 23; a second light modulation element 30B that modulates the fluorescence B emitted from the second light source device 22; and a third light modulation element 30G that modulates the fluorescence G emitted from the third light source device 24. A light combining element 64 combines the red modulated light R1 emitted from the first light modulation element 30R, the blue modulated light B1 emitted from the second light modulation element 30B, and the green modulated light G1 emitted from the third light modulation element 30G.

[0140] According to this structure, compared to the projector of the first embodiment that only uses the phosphor Y emitted from the first light source device, the color reproduction of the image can be improved. Furthermore, unlike the third embodiment, the liquid crystal panel does not have a color filter, and the light source device and the light modulation element are not driven sequentially in time, thus enabling the projection of a color image. Therefore, a liquid crystal panel with a high-speed response is not required, the design of the light modulation element becomes easier, and a high-resolution and bright image can be obtained.

[0141] [Fifth Implementation]

[0142] The following uses Figure 14 The fifth embodiment of the present invention will be described.

[0143] The basic structure of each light source device in the projector of the fifth embodiment is the same as that in the first embodiment, so the description of the basic structure of the light source device is omitted.

[0144] Figure 14 This is a schematic structural diagram of the projector 15 according to the fifth embodiment.

[0145] exist Figure 14 In this document, the same reference numerals are used for the same components as those used in the previous embodiments, and descriptions are omitted.

[0146] like Figure 14 As shown, the projector 15 of this embodiment includes a first light source device 20, a second light source device 22, a first light modulation element 30Y, a second light modulation element 30B, a light combining element 60, and an angle conversion lens 40. The first light source device 20 and the second light source device 22 are the same as those in the second embodiment.

[0147] The first light modulation element 30Y modulates the yellow fluorescence Y emitted from the first light source device 20. The second light modulation element 30B modulates the blue fluorescence B emitted from the second light source device 22. Both the first light modulation element 30Y and the second light modulation element 30B are constructed from transmissive liquid crystal panels. The first light modulation element 30Y may or may not have color filters for red and green colors. The second light modulation element 30B does not have color filters.

[0148] The light combining element 60 has the same structure as the light combining element 60 of the second embodiment, but differs from the second embodiment in that it combines the modulated light modulated by each light modulating element. That is, the light combining element 60 combines the yellow modulated light Y1 emitted from the first light modulating element 30Y and the blue modulated light B1 emitted from the second light modulating element 30B. In addition, when the first light modulating element 30Y is equipped with a two-color filter, the aforementioned yellow modulated light Y1 is light that includes red modulated light and green modulated light.

[0149] An angle conversion lens 40 is provided between the first light source device 20 and the first light modulation element 30Y. An angle conversion lens 40 is provided between the second light source device 22 and the second light modulation element 30B.

[0150] [Effects of the 5th Embodiment]

[0151] In this embodiment, the same effect as in the first embodiment can also be achieved, such as a focusless projector 15 that can project images with less speckle noise.

[0152] The projector 15 of this embodiment includes: a first light source device 20 that emits yellow-band fluorescence Y; a second light source device 22 that emits blue-band fluorescence B; a first light modulation element 30Y that modulates the fluorescence Y emitted from the first light source device 20; and a second light modulation element 30B that modulates the fluorescence B emitted from the second light source device 22. A light combining element 60 combines the yellow modulated light Y1 emitted from the first light modulation element 30Y and the blue modulated light B1 emitted from the second light modulation element 30B.

[0153] According to this structure, compared to the projector 10 of the first embodiment which only uses fluorescence Y emitted from the first light source device, the color reproduction of the image can be improved. Furthermore, only two sets of light source devices and two sets of light modulation elements are needed; therefore, a projector 15 with a simpler structure compared to the projector 14 of the fourth embodiment can be realized. When the first light modulation element 30Y is equipped with red and green color filters, a color image composed of red, green, and blue light can be obtained. When the first light modulation element 30Y is not equipped with color filters, a color image composed of yellow and blue light can be obtained.

[0154] [Sixth Implementation]

[0155] The following uses Figure 15 The sixth embodiment of the present invention will be described.

[0156] The basic structure of the light source device in the projector of the sixth embodiment is the same as that in the first embodiment, so the description of the basic structure of the light source device is omitted.

[0157] Figure 15 This is a schematic structural diagram of the projector according to the sixth embodiment.

[0158] exist Figure 15 In this document, the same reference numerals are used for the same components as those used in the previous embodiments, and descriptions are omitted.

[0159] like Figure 15 As shown, the projector 16 of this embodiment includes a first light source device 20, a light modulation element 32, a reflective polarizing plate 69, and an angle conversion lens 40. The first light source device 20 is the same as the light source device 20 of the first embodiment.

[0160] In embodiments 1 through 5, a transmissive light modulation element was used as the light modulation element. In contrast, in this embodiment, a reflective light modulation element is used as the light modulation element. The light modulation element 32 in this embodiment is, for example, composed of a reflective liquid crystal panel called LCOS. The reflective liquid crystal panel has a general structure, so its description is omitted.

[0161] A reflective polarizer 69 is disposed between the angle conversion lens 40 and the light modulation element 32. The reflective polarizer 69 is configured at an angle of, for example, 45° relative to the optical axis AX1 of the first light source device 20. The reflective polarizer 69 allows first linearly polarized light with a predetermined polarization direction to pass through, and reflects second linearly polarized light with a polarization direction different from that of the first linearly polarized light. By disposing this reflective polarizer 69 between the angle conversion lens 40 and the light modulation element 32, the fluorescence Y emitted from the first light source device 20 can be modulated.

[0162] [Effects of the 6th Embodiment]

[0163] In this embodiment, the same effect as in the first embodiment can also be achieved, such as a focusless projector 16 that can project images with less speckle noise.

[0164] In the projector 16 of this embodiment, the light modulation element 32 is composed of a reflective light modulation element.

[0165] Based on this structure, the aperture ratio of each pixel of the light modulation element 32 can be increased, thereby realizing a projector 16 capable of projecting bright images.

[0166] [Seventh Implementation]

[0167] The following uses Figure 16 The seventh embodiment of the present invention will be described.

[0168] The basic structure of the light source device in the projector of the seventh embodiment is the same as that in the first embodiment, so the description of the basic structure of the light source device is omitted.

[0169] Figure 16 This is a schematic structural diagram of the projector 17 according to the seventh embodiment.

[0170] exist Figure 16 In this document, the same reference numerals are used for the same components as those used in the previous embodiments, and descriptions are omitted.

[0171] like Figure 16 As shown, the projector 17 of this embodiment includes a first light source device 20, a light modulation element 34, an internal total internal reflection prism (TIR prism) 72, and an angle conversion lens 40. The first light source device 20 is the same as the light source device 20 of the first embodiment.

[0172] In embodiments 1 through 6, a liquid crystal panel was used as the light modulation element. In contrast, in this embodiment, a micromirror-type light modulation element is used. The light modulation element 34 in this embodiment is, for example, a digital micromirror device (DMD). The DMD has a structure in which multiple micromirrors are arranged in a matrix.

[0173] The internal total internal reflection prism 72 consists of two prisms arranged opposite each other with an air layer of a certain thickness sandwiched between them, and has a reflecting surface 72r. The reflecting surface 72r is set at an angle such that the fluorescence Y emitted from the first light source device 20 is totally reflected toward the light modulation element 34. The DMD switches the reflection direction of the fluorescence Y between the direction transmitted through the reflecting surface 72r and the direction reflected by the reflecting surface 72r by switching the tilt direction of each of the multiple micromirrors.

[0174] An angle conversion lens 40 is positioned between the first light source device 20 and the internal total reflection prism 72.

[0175] [Effects of the 7th Embodiment]

[0176] In this embodiment, the same effect as in the first embodiment can also be achieved, such as a focusless projector 17 that can project images with less speckle noise.

[0177] Furthermore, the scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention. Additionally, one aspect of the present invention can be a structure that appropriately combines the characteristic portions of the various embodiments described above.

[0178] For example, in the above embodiments, regarding the light source device equipped with a wavelength conversion component that emits blue fluorescence, a light guide component that does not contain a phosphor and guides the incident blue light without wavelength conversion can be used instead of the wavelength conversion component. Specifically, for example, it can be configured to use a light guide component in which one end of a quadrangular prism is ground into a quadrangular pyramid shape and a diffusion layer is formed at the other end of the quadrangular prism, so that the blue light emitted from the blue LED enters through the diffusion layer from the other end of the light guide component. In this structure, a focusless projector capable of projecting images with low speckle noise can also be realized.

[0179] In the above embodiments, the light source device equipped with a wavelength conversion component that emits yellow fluorescence can also be configured such that a dichroic filter is disposed after the light source device to extract either the green light component or the red light component from the yellow fluorescence and emit either green or red fluorescence. Alternatively, it can be configured such that a dichroic mirror is disposed after the light source device to separate the green light component and the red light component from the yellow fluorescence, so that the green light and red light are respectively incident on the light modulation element.

[0180] In the above embodiment, the angle conversion lens is disposed between the light source device and the light modulation element, but it can also be disposed after the light modulation element. In other words, the light modulation element can also be disposed between the light source device and the angle conversion lens. According to this structure, compared with the structure in which the angle conversion lens is disposed between the light source device and the light modulation element, the distance between the light source device and the light modulation element is shortened, thus enabling miniaturization of the light modulation element. In addition, the angle conversion lens is not limited to one, and multiple angle conversion lenses can be used.

[0181] In the above embodiment, the shape of the emission portion is formed as a quadrangular pyramid, but the second end of the emission portion may not be completely sharp, may be flat, or may be rounded into a curved surface. Based on these structures, the possibility of breakage of the second end can be reduced during the manufacturing process of the light source device. Furthermore, since fluorescence almost does not reach the end of the second end, even if the end of the second end is slightly flat or curved, there is almost no concern about a reduction in fluorescence extraction efficiency. Moreover, when the effective modulation region of the light modulation element is quadrilateral, the shape of the emission portion is preferably quadrilateral, but in addition to a quadrangular pyramid, it can also be conical, multi-faceted pyramidal, etc. Even in this case, a reduction in speckle noise can be achieved.

[0182] In the above embodiments, examples of light modulation elements based on image information include transmissive liquid crystal panels, reflective liquid crystal panels, and DMDs. However, in addition to these light modulation elements, slides (positive or negative films) whose projected images do not change over time, specimens on microscope specimens, OHP slides, and cutouts for shadow puppetry can also be used. When using such a light modulation element, the projected image can be switched by appropriately replacing it with a light modulation element having other patterns.

[0183] In the projector 10 of the first embodiment described above, the example given is that a light source device emitting yellow fluorescence Y is used as the first light source device 20. However, the present invention is not limited to this. The first light source device 20 may be replaced by any of the following: a light source device emitting red fluorescence R, such as the first light source device 23; a light source device emitting blue fluorescence B, such as the second light source device 22; and a light source device emitting green fluorescence G, such as the third light source device 24.

[0184] Furthermore, the specific descriptions of the shape, quantity, configuration, materials, etc. of the various components of the light source device and projector are not limited to the above embodiments and can be appropriately modified.

[0185] The projector of one embodiment of the present invention may also have the following structure.

[0186] One aspect of the present invention is a projector that projects images onto a projected object without focus. The projector includes: a first light source device; and a light modulation element that modulates light emitted from the first light source device, the first light source device having: a light-emitting element that emits first light having a first wavelength band; a wavelength conversion component comprising a phosphor that converts the first light emitted from the light-emitting element into second light having a second wavelength band different from the first wavelength band; and an emission portion disposed along the central axis of the wavelength conversion component, emitting the second light generated by the wavelength conversion component, the emission portion having: a first end opposite to the wavelength conversion component; a second end located along the central axis on the side opposite to the first end; and a tapering portion whose cross-sectional area perpendicular to the central axis gradually decreases from the first end toward the second end, the tapering portion having a light-emitting surface inclined relative to the central axis, emitting the second light.

[0187] In one embodiment of the projector of the present invention, the wavelength conversion component may have: a first surface and a second surface located on opposite sides of each other in the longitudinal direction of the wavelength conversion component; and a third surface that intersects the first surface and the second surface, wherein the second light is emitted from the first surface toward the emission portion, and the first light emitted from the light-emitting element is incident on the third surface.

[0188] In one embodiment of the projector of the present invention, the first surface may be rectangular in shape, and the effective modulation area of ​​the light modulation element may also be rectangular in shape.

[0189] In one embodiment of the projector of the present invention, the shape of the emission portion may be a square pyramid.

[0190] In one embodiment of the projector of the present invention, when the length of the ejector portion along the length direction is H and the length of the ejector portion along the direction intersecting the length direction is L, the ratio of H to L, H / L, is 1.3 or more.

[0191] In one embodiment of the projector of the present invention, the wavelength conversion component and the emission section may be constituted as an integral component.

[0192] In one embodiment of the projector of the present invention, the emission portion may be composed of a light-transmitting component separate from the wavelength conversion component, and may be coupled to the wavelength conversion component.

[0193] Alternatively, the projector of one embodiment of the present invention may also have an angle conversion lens that allows the second light emitted from the emission portion to pass through, wherein the radiation angle of the second light emitted from the angle conversion lens is smaller than the radiation angle of the second light incident on the angle conversion lens.

[0194] In one embodiment of the projector of the present invention, the angle conversion lens may be disposed between the first light source device and the light modulation element.

[0195] In one embodiment of the projector of the present invention, the angle conversion lens may also be composed of an aspherical lens.

[0196] Alternatively, the projector of one embodiment of the present invention may further include: a second light source device that emits third light having a third band different from the first band and the second band; and a light combining element that combines the second light emitted from the first light source device and the third light emitted from the second light source device to emit a first combined light, wherein the light modulation element modulates the first combined light emitted from the light combining element.

[0197] Alternatively, in one embodiment of the present invention, the projector may further include a third light source device that emits a fourth light having a fourth band different from the first, second, and third bands. The light combining element combines the second light emitted from the first light source device, the third light emitted from the second light source device, and the fourth light emitted from the third light source device to emit a second combined light. The light modulation element modulates the second combined light emitted from the light combining element.

[0198] In one embodiment of the projector of the present invention, the light modulation element may also include a color filter.

[0199] In one embodiment of the projector of the present invention, the first light source device, the second light source device, and the third light source device may be lit sequentially according to time, and the light modulation element may be driven synchronously with the lighting timing of the first light source device, the second light source device, and the third light source device.

[0200] Alternatively, the projector of one embodiment of the present invention may further include: a second light source device that emits third light having a third band different from the first band and the second band; and a light combining element, the light modulation element having: a first light modulation element that modulates the second light emitted from the first light source device; and a second light modulation element that modulates the third light emitted from the second light source device, the light combining element combining the first modulated light emitted from the first light modulation element and the second modulated light emitted from the second light modulation element.

[0201] Alternatively, in one embodiment of the present invention, the projector may further include a third light source device that emits a fourth light having a fourth band different from the first band, the second band, and the third band; the light modulation element may further include a third light modulation element that modulates the fourth light emitted from the third light source device; and the light combining element combines the first modulated light, the second modulated light, and the third modulated light emitted from the third light modulation element.

[0202] In one embodiment of the projector of the present invention, the light modulation element may be composed of a transmissive light modulation element.

[0203] In one embodiment of the projector of the present invention, the light modulation element may be composed of a reflective light modulation element.

Claims

1. A projector that projects an image onto a target object without focusing, the projector comprising: The first light source device; and An optical modulation element that modulates the light emitted from the first light source device. The first light source device includes: A light-emitting element that emits first light with a first wavelength; A wavelength conversion component, comprising a phosphor, converts the first light emitted from the light-emitting element into second light having a second wavelength band different from the first band; and The emission section, which is arranged along the central axis of the wavelength conversion component, emits the second light generated by the wavelength conversion component. The emission portion has: a first end portion opposite to the wavelength conversion component; a second end portion located along the central axis on the opposite side to the first end portion; and a tapering portion, the cross-sectional area of ​​which, perpendicular to the central axis, gradually decreases from the first end portion toward the second end portion. The tapering section has a light-emitting surface that is inclined relative to the central axis, emitting the second light beam. The wavelength conversion component has: a first surface and a second surface located on opposite sides of each other along the length of the wavelength conversion component; and a third surface that intersects the first surface and the second surface. The second light is emitted from the first surface toward the emission portion. The first light emitted from the light-emitting element is incident on the third surface. When the length of the ejection section along the length direction is H, and the length of the ejection section along the direction intersecting the length direction is L, the ratio of H to L, H / L, is 1.3 or more and 3.0 or less. The first surface is rectangular in shape, and the effective modulation area of ​​the optical modulation element is rectangular in shape.

2. The projector according to claim 1, wherein, The ejection section is shaped like a four-sided pyramid.

3. The projector according to claim 1 or 2, wherein, The wavelength conversion component and the emission section are composed of an integral part.

4. The projector according to claim 1 or 2, wherein, The emission section is composed of a light-transmitting component that is separate from the wavelength conversion component, and is connected to the wavelength conversion component.

5. The projector according to claim 1 or 2, wherein, The projector also includes an angle-converting lens that allows the second light emitted from the emission section to pass through. The radiation angle of the second light emitted from the angle conversion lens is smaller than the radiation angle of the second light incident on the angle conversion lens.

6. The projector according to claim 5, wherein, The angle conversion lens is disposed between the first light source device and the light modulation element.

7. The projector according to claim 5, wherein, The angle conversion lens is composed of an aspherical lens.

8. The projector according to claim 1 or 2, wherein, The projector also features: A second light source device emits third light having a third wavelength band different from the first and second wavelength bands; and A light combining element that combines the second light emitted from the first light source device and the third light emitted from the second light source device to emit a first combined light. The optical modulation element modulates the first synthesized light emitted from the optical synthesis element.

9. The projector according to claim 8, wherein, The projector also includes a third light source device, which emits a fourth light with a fourth wavelength different from the first, second, and third wavelengths. The light combining element combines the second light emitted from the first light source device, the third light emitted from the second light source device, and the fourth light emitted from the third light source device to emit a second combined light. The optical modulation element modulates the second synthesized light emitted from the optical synthesis element.

10. The projector according to claim 9, wherein, The optical modulation element includes a color filter.

11. The projector according to claim 9, wherein, The first light source device, the second light source device, and the third light source device are lit up sequentially according to time. The light modulation element is driven synchronously with the lighting timing of the first light source device, the second light source device, and the third light source device.

12. The projector according to claim 1 or 2, wherein, The projector also features: A second light source device emits third light having a third wavelength band different from the first and second wavelength bands; and Photosynthesizing element, The optical modulation element includes: a first optical modulation element that modulates the second light emitted from the first light source device; and a second optical modulation element, which modulates the third light emitted from the second light source device. The light combining element combines a first modulated light emitted from the first light modulating element and a second modulated light emitted from the second light modulating element.

13. The projector according to claim 12, wherein, The projector also includes a third light source device, which emits a fourth light with a fourth wavelength different from the first, second, and third wavelengths. The optical modulation element further includes a third optical modulation element for modulating the fourth light emitted from the third light source device. The light combining element combines the first modulated light, the second modulated light, and the third modulated light emitted from the third light modulating element.

14. The projector according to claim 1 or 2, wherein, The optical modulation element is composed of a transmissive optical modulation element.

15. The projector according to claim 1 or 2, wherein, The optical modulation element is composed of a reflective optical modulation element.

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