Phosphor wheel unit and projection-type image display device

Abstract

To provide a phosphor wheel unit and a projection type image display device having improved cooling efficiency.SOLUTION: The phosphor wheel unit includes a phosphor wheel configured to emit fluorescent light from incident light, a motor configured to rotationally drive the phosphor wheel, a first heat exchanger having an airflow inlet surface on which a plurality of fins are arranged and into which a part or all of an airflow generated by rotation of the phosphor wheel flows, and a restriction member configured to restrict a direction of the airflow generated by the rotation of the phosphor wheel. On a plane perpendicular to the direction in which the base 107f of the phosphor wheel extends, the angle between the direction of the airflow restricted by the restriction member and the direction perpendicular to the axis of rotation of the phosphor wheel is greater than or equal to 0 degrees but smaller than or equal to 45 degrees. The airflow inlet surface is disposed on the extension of the direction of the airflow restricted by the restriction member, and the gas cooled by the first heat exchanger returns to the phosphor wheel.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present disclosure relates to a phosphor wheel unit, and more particularly to a phosphor wheel unit having a cooling structure for cooling a phosphor wheel, and a projection-type image display device including the same. [Background technology]

[0002] A projection-type image display device can convert light into a different color by irradiating it onto a phosphor wheel. However, nearly half of the energy of the irradiated light is not converted and becomes heat, causing the phosphor wheel to become hot and therefore require cooling.

[0003] For example, in Patent Document 1, air is circulated inside a housing, and the air heated by a fluorescent color wheel (phosphor wheel) is passed through a heat exchanger to be cooled. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6773789 Summary of the Invention [Problem to be solved by the invention]

[0005] In recent years, the amount of light irradiated onto the phosphor wheel unit has tended to increase, and it is therefore necessary to improve the cooling efficiency of the phosphor wheel unit.

[0006] An object of the present disclosure is to provide a phosphor wheel unit and a projection-type image display device that have improved cooling efficiency in the phosphor wheel unit. [Means for solving the problem]

[0007] The phosphor wheel unit of the present disclosure includes a phosphor wheel that converts incident light into fluorescent light, a motor that drives the phosphor wheel to rotate, a first heat exchanger having an airflow inlet surface on which a plurality of fins are arranged and through which some or all of the airflow generated by the rotation of the phosphor wheel flows, and a regulating member that regulates the direction of the airflow generated by the rotation of the phosphor wheel. On a plane perpendicular to the extension direction of base material 107f of the phosphor wheel, the angle between the direction of the airflow regulated by the regulating member and the direction perpendicular to the rotation axis of the phosphor wheel is between 0 and 45 degrees. The airflow inlet surface is located on an extension of the direction of the airflow regulated by the regulating member, and the gas cooled by the first heat exchanger returns to the phosphor wheel.

[0008] The projection-type image display device of the present disclosure includes the above-described phosphor wheel unit. [Effects of the Invention]

[0009] The phosphor wheel unit of the present disclosure can provide a phosphor wheel unit and a projection-type image display device with improved cooling efficiency. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an overall front view of a phosphor wheel unit according to a first embodiment; [Figure 2] A perspective view of the phosphor wheel unit with the housing removed [Figure 3] A perspective view of the phosphor wheel unit with the housing removed [Figure 4] Front view of the phosphor wheel unit with the housing removed [Figure 5] A perspective view of a phosphor wheel housed in a wheel case. [Figure 6] FIG. 1 is a perspective view of a first heat exchanger as viewed from a side wall of a housing; [Figure 7] FIG. 1 is a perspective view illustrating the flow of gas within a phosphor wheel unit. [Figure 8] FIG. 10 is an overall perspective view of a phosphor wheel unit according to a second embodiment; [Figure 9A]FIG. 10 is a perspective view of a phosphor wheel unit with a housing removed according to a second embodiment; [Figure 9B] Rear view of the wheel case of the second embodiment [Figure 9C] FIG. 10 is an explanatory diagram of a phosphor wheel unit according to a modified example of the second embodiment. [Figure 9D] FIG. 10 is an explanatory diagram of a phosphor wheel unit according to a modified example of the second embodiment. [Figure 10] FIG. 10 is a schematic diagram showing the overall configuration of a projection-type image display device 1 according to a third embodiment. [Figure 11] 1 is a top view of a phosphor wheel unit with a housing removed according to a first modified example; [Figure 12] FIG. 10 is a perspective view of a phosphor wheel unit according to a second modified example with the housing removed; [Figure 13] 10 is a top view of the phosphor wheel unit of the third modified example with the housing removed. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, more detailed explanation than necessary may be omitted. For example, detailed explanation of well-known matters or redundant explanation of substantially the same configuration may be omitted. This is to avoid unnecessary redundancy in the following explanation and to facilitate understanding by those skilled in the art.

[0012] The inventor(s) provide the accompanying drawings and the following description to enable those skilled in the art to fully understand the present disclosure, and do not intend for them to limit the subject matter described in the claims.

[0013] (Embodiment 1) Hereinafter, the first embodiment will be described with reference to Figs. 1 to 4. Fig. 1 is an overall front view of a phosphor wheel unit 100 according to the first embodiment of the present disclosure. Figs. 2 and 3 are perspective views of the phosphor wheel unit 100 with the housing 101 removed. Fig. 4 is a front view of the phosphor wheel unit 100 with the housing 101 removed. In each figure, the direction in which the excitation light Lt is incident is the Y direction, the plane in which the phosphor wheel 107 receives the excitation light Lt is the XZ plane formed by the X direction and the Z direction perpendicular to the X direction, and the XZ plane is perpendicular to the Y direction.

[0014] [1-1.Configuration] 1, the phosphor wheel unit 100 includes a housing 101, a second heat exchanger 103 disposed outside the housing 101, and a fan 105. The housing 101 is made of, for example, metal.

[0015] As shown in FIGS. 2 to 4, the phosphor wheel unit 100 includes a phosphor wheel 107, a wheel case 109, a motor 111, a first heat exchanger 113, and a heat conduction member 115 within the housing 101.

[0016] The phosphor wheel 107 converts the incident excitation light Lt into fluorescent light and emits the converted fluorescent light. The phosphor wheel 107 has an incident surface 107a on which the excitation light Lt is incident, and a phosphor layer 107b is disposed on the incident surface 107a. The incident excitation light Lt, for example, in the blue range, causes the phosphor layer 107b to emit fluorescent light in the yellow range that includes color light in the green and red range components.

[0017] Wheel case 109 houses phosphor wheel 107 and regulates the direction of airflow generated by the rotation of phosphor wheel 107. Wheel case 109 is made of, for example, metal. Motor 111 drives phosphor wheel 107 to rotate around rotation axis Ar (see FIG. 5).

[0018] The first heat exchanger 113 passes the airflow from the phosphor wheel 107 through it, and at this time, the heat of the air is conducted and cooled. The first heat exchanger 113 has a plurality of rectangular fins 113a arranged parallel to the Z direction. As the air passes between the fins 113a, the heat of the air is dissipated to the fins 113a. The fins 113a are made of a metal with high thermal conductivity, such as copper or aluminum. The housing 101 is a sealed space, and the air cooled by the first heat exchanger 113 returns to the phosphor wheel 107. In this way, an airflow is generated within the housing 101 that circulates from the phosphor wheel 107 through the first heat exchanger 113 and back to the phosphor wheel 107.

[0019] The heat conduction member 115 conducts heat from the first heat exchanger 113 to the second heat exchanger 103. The heat conduction member 115 is, for example, a heat pipe, and connects the first heat exchanger 113 arranged inside the housing 101 with the second heat exchanger 103 arranged outside the housing 101.

[0020] The fan 105 sends cooling air to the second heat exchanger 103, thereby dissipating the heat of the second heat exchanger 103 into the cooling air and improving the cooling efficiency of the second heat exchanger 103. In this way, the heat inside the housing 101 can be efficiently dissipated to the outside of the housing 101.

[0021] The phosphor wheel unit 100 further includes a convex lens 117 that focuses the incident excitation light onto the phosphor wheel 107 .

[0022] <Phosphor wheel> Next, the phosphor wheel 107 and the wheel case 109 will be described with reference to Figures 4 and 5. Figure 5 is a perspective view of the phosphor wheel 107 housed in the wheel case 109.

[0023] The phosphor wheel 107 includes a metal base 107f, which has an incident surface 107a on the light-incident side and a back surface 107c opposite the incident surface 107a. An annular phosphor layer 107b is disposed on the incident surface 107a of the base 107f. The phosphor wheel 107 also includes a plurality of fins 107d disposed on the back surface 107c of the base 107f. The fins 107d are, for example, curved plates that curve from the outer periphery toward the center of the phosphor wheel 107 and stand upright on the back surface 107c. The provision of the fins 107d increases the amount of air generated by the rotation of the phosphor wheel 107. This improves the cooling efficiency of the phosphor wheel 107.

[0024] Wheel case 109 has intake port 109a on the rear surface 107c side of phosphor wheel 107 through which gas flows in, and exhaust port 109b, perpendicular to the direction of rotation axis Ar of phosphor wheel 107, through which gas that has cooled phosphor wheel 107 is exhausted. Wheel case 109 has a shape that surrounds the outer periphery of disc-shaped phosphor wheel 107, and rectangular exhaust port 109b is formed in a portion surrounding the outer periphery. Therefore, the direction of the airflow generated by the rotation of phosphor wheel 107 is regulated by wheel case 109. On a plane (XY plane) perpendicular to the extension direction of base material 107f of phosphor wheel 107, direction Da of the regulated airflow is perpendicular to the direction of rotation axis Ar of phosphor wheel 107. Here, direction Da of the regulated airflow refers to the main direction of the regulated airflow, and "perpendicular" includes a completely vertical state and a state tilted by approximately a few degrees from the completely vertical state.

[0025] Phosphor wheel 107 dissipates heat into the gas flowing in through intake port 109a, causing the gas with an increased temperature to be exhausted through exhaust port 109b. The opening surface of exhaust port 109b is, for example, rectangular. The longitudinal length L1 of exhaust port 109b is substantially the same as the length L2 in the direction in which fins 113a of first heat exchanger 113 are arranged (see FIG. 4). The normal direction Nd1 of the opening surface of exhaust port 109b is perpendicular to the direction of rotation axis Ar of phosphor wheel 107. Here, "perpendicular" includes both a completely perpendicular state and a state tilted by ±several degrees from the completely perpendicular state.

[0026] <First heat exchanger> Next, the first heat exchanger 113 will be described with reference to Fig. 6. Fig. 6 is a perspective view of the first heat exchanger 113 as seen from the side where the phosphor wheel is arranged.

[0027] The first heat exchanger 113 has an airflow inlet surface 113b through which some or all of the airflow generated by the rotation of the phosphor wheel 107 flows. The airflow inlet surface 113b is positioned opposite the exhaust port 109b of the wheel case 109, for example, parallel to it. A normal direction Nd1 to the opening surface of the exhaust port 109b of the wheel case 109 and a normal direction Nd2 to the airflow inlet surface 113b are parallel to each other. Here, "parallel" includes both completely parallel and tilted states of ±several degrees from the completely parallel state. This allows the airflow flowing out from the exhaust port 109b of the wheel case 109 to be efficiently guided into the first heat exchanger 113.

[0028] The first heat exchanger 113 has an airflow outlet surface 113c through which the gas cooled by the first heat exchanger 113 flows out. In the first embodiment, the side wall 101a (see FIG. 7) of the housing 101 is disposed on the side opposite the phosphor wheel 107 from the first heat exchanger 113. Therefore, the airflow that flows out from the exhaust port 109b of the wheel case 109 and passes between the fins 113a of the first heat exchanger 113 strikes the side wall 101a. The airflow that strikes the side wall 101a then flows again between the fins 113a toward the inside of the housing 101 and flows out from the airflow outlet surface 113c. The airflow inlet surface 113b and the airflow outlet surface 113c are disposed on the same plane. The first heat exchanger 113 may be in contact with or spaced apart from the side wall 101a of the housing 101. The sidewall 101a may also be formed by the fins 113a of the first heat exchanger 113. In the first heat exchanger 113, the flow path space formed by each fin 113a has no obstruction to the outflow of air in the +X direction, except for some crimped portions. Therefore, the size of the area of ​​the airflow inlet surface 113b and the airflow outlet surface 113c varies depending on, for example, the speed of the airflow flowing between each fin 113a, and there is no clear boundary between the airflow inlet surface 113b and the airflow outlet surface 113c. In Figures 6 and 7, the airflow inlet surface 113b and the airflow outlet surface 113c are separated by a fixed rectangular shape for ease of understanding.

[0029] Next, cooling of the airflow inside the housing 101 will be described with reference to Fig. 7. Phosphor wheel 107, rotated by motor 111, generates an airflow in the radial direction. The temperature of the generated airflow has been increased by phosphor wheel 107, and the flow is restricted by the internal shape of wheel case 109, and the airflow flows from the opening surface of exhaust port 109b into airflow inlet surface 113b of first heat exchanger 113.

[0030] The airflow that has flowed into the airflow inlet surface 113b passes between the fins 113a of the first heat exchanger 113, hits the side wall 101a, changes direction, and flows out from the airflow outlet surface 113c. On the way from the airflow inlet surface 113b to the airflow outlet surface 113c, the airflow dissipates heat to the first heat exchanger 113 and is cooled. The cooled airflow flows from the airflow outlet surface 113c into the intake port 109a of the wheel case 109, where it can circulate within the housing 101 and be cooled.

[0031] [1-2. Effects, etc.] As described above, phosphor wheel unit 100 according to the present embodiment includes phosphor wheel 107 that emits fluorescent light from incident excitation light Lt, motor 111 that rotates phosphor wheel 107, first heat exchanger 113 having an array of fins 113a and airflow inlet surface 113b through which a portion or all of the airflow generated by the rotation of phosphor wheel 107 flows, and wheel case 109 that regulates the direction of the airflow generated by the rotation of phosphor wheel 107. On a plane (XY plane) perpendicular to the extension direction of base material 107f of phosphor wheel 107, the direction Da of the airflow regulated by wheel case 109 is perpendicular to the direction of rotation axis Ar of phosphor wheel 107. Airflow inlet surface 113b is located on an extension of the direction Da of the airflow regulated by wheel case 109. The gas cooled by first heat exchanger 113 returns to phosphor wheel 107.

[0032] The gas whose temperature has been increased by phosphor wheel 107 flows radially as phosphor wheel 107 rotates. The direction of this radially flowing airflow is restricted by wheel case 109. Because airflow inlet surface 113b of first heat exchanger 113 is disposed on an extension of this restricted airflow direction Da, gas with the fastest flow rate can enter first heat exchanger 113. This allows gas with a fast flow rate to flow entirely between the multiple fins 113a of first heat exchanger 113, thereby efficiently conducting heat from the gas. The gas cooled in this way returns to phosphor wheel 107, thereby improving the cooling efficiency of phosphor wheel 107.

[0033] Furthermore, the direction Da of the airflow regulated by the phosphor wheel case 109 is parallel to the normal direction Nd2 of the airflow inlet surface 113b of the first heat exchanger 113. This allows the gas, whose flow direction is regulated by the phosphor wheel 107, to efficiently enter the airflow inlet surface 113b of the first heat exchanger 113.

[0034] Furthermore, the normal direction Nd1 of the opening surface of exhaust port 109b of wheel case 109 is perpendicular to the direction of rotation axis Ar of phosphor wheel 107, and airflow inlet surface 113b and the opening surface of exhaust port 109b are parallel. This allows the airflow flowing out from exhaust port 109b of wheel case 109 to flow perpendicularly into airflow inlet surface 113b of first heat exchanger 113, so that most of the airflow flowing out from exhaust port 109b can be received by first heat exchanger 113. This improves cooling efficiency. Furthermore, the direction Da of the airflow restricted by phosphor wheel case 109 is parallel to the normal direction Nd1 of the opening surface of exhaust port 109b.

[0035] Furthermore, sidewall 101a is disposed at a position where it is hit by gas that has flowed into airflow inlet surface 113b and passed through first heat exchanger 113, and first heat exchanger 113 has airflow outlet surface 113c through which gas cooled by first heat exchanger 113 flows out. The gas that flows into first heat exchanger 113 from airflow inlet surface 113b hits sidewall 101a and flows out from airflow outlet surface 113c. By making the airflow that has passed through first heat exchanger 113 hit sidewall 101a, it is possible for the airflow to flow between multiple fins 113a extending in the direction of rotation axis Ar of phosphor wheel 107. This makes it possible to effectively utilize the space within housing 101 and improve cooling efficiency.

[0036] Furthermore, the length L1 of the exhaust port 109b of the wheel case 109 in the longitudinal direction is equal to the length L2 of the airflow inlet surface 113b in the direction in which the multiple fins 113a are arranged in the opposing first heat exchanger 113. Therefore, the airflow flowing out from the exhaust port 109b of the wheel case 109 can be made to flow evenly between the multiple fins 113a in the first heat exchanger 113.

[0037] Furthermore, phosphor wheel 107 is provided with fins 107d on back surface 107c opposite incident surface 107a onto which excitation light Lt is incident. This increases the amount of airflow generated when phosphor wheel 107 is rotated, improving cooling efficiency. Furthermore, providing fins 107d increases the surface area of ​​back surface 107c of phosphor wheel 107, improving cooling efficiency.

[0038] Furthermore, housing 101 accommodates phosphor wheel 107, motor 111, and first heat exchanger 113. Second heat exchanger 103 having a plurality of fins 103a is disposed outside housing 101, and first heat exchanger 113 and second heat exchanger 103 are connected by thermally conductive member 115. This allows heat from first heat exchanger 113 inside housing 101 to be conducted to second heat exchanger 103 outside housing 101 and dissipated outside housing 101, thereby improving the cooling efficiency of first heat exchanger 113.

[0039] (Embodiment 2) Next, a phosphor wheel unit 100A according to a second embodiment will be described with reference to Fig. 8, Fig. 9A, and Fig. 9B. Fig. 8 is an overall perspective view of the phosphor wheel unit 100A according to the second embodiment. Fig. 9A is a perspective view of the phosphor wheel unit 100A with the housing 101A removed. Fig. 9B is a rear view of the wheel case 109A.

[0040] As shown in Figures 8 and 9, phosphor wheel unit 100A of embodiment 2 is configured to use excitation light Lt by passing it through phosphor wheel 107A in a time-division manner. Except for this point and points described below, phosphor wheel unit 100 of embodiment 1 and phosphor wheel unit 100A of embodiment 2 have the same configuration. Phosphor wheel unit 100A of embodiment 2 is used in a 1DLP type projection image display device.

[0041] 9A , phosphor wheel 107A of the second embodiment has two through-holes 107Ae on incident surface 107Aa, on the same circumference as phosphor layer 107Ab. Furthermore, mirrors 121 and 123 are arranged on the back side of phosphor wheel 107A, opposite incident surface 107Aa, as optical members for receiving light that has passed through through-holes 107Ae of phosphor wheel 107A. Therefore, excitation light Lt that has passed through through-hole 107Ae of phosphor wheel 107A is reflected by mirror 121, bent by 90 degrees, and then reflected by mirror 123, bent by 90 degrees, and then continues. As a result, excitation light Lt in the direction opposite to the direction of excitation light Lt that entered phosphor wheel 107A is emitted from phosphor wheel unit 100A in a time-division manner. 9B, intake port 109Aa of wheel case 109A according to the second embodiment has a shape in which the opening is enlarged even in the peripheral portion through which excitation light Lt passes so as not to obstruct the excitation light Lt passing through through-hole 107Ae toward mirror 121. Therefore, wheel case 109A on the rear side has a shape in which a portion of the annular wheel case 109A is missing. Note that, of the excitation light Lt, the light that passes through through-hole 107Ae does not actually perform excitation, but is here described as excitation light and is given the same reference numeral.

[0042] In phosphor wheel unit 100A, first heat exchanger 113 is disposed perpendicular to rotation axis Ar of phosphor wheel 107A, as in embodiment 1. Therefore, since mirror 121 is disposed on the rear side of phosphor wheel 107A, first heat exchanger 113 of a sufficient size can be disposed compared to the case where a heat exchanger is disposed on the rear side of phosphor wheel 107A.

[0043] In the phosphor wheel unit 100A of embodiment 2, the same effect as in embodiment 1 can be achieved, allowing the heat of the air flowing from the phosphor wheel 107A to be efficiently dissipated, thereby improving the cooling efficiency of the phosphor wheel unit 100A.

[0044] In the second embodiment described above, mirror 121 is provided on the back side of phosphor wheel 107A as an optical member that receives light that has passed through through-hole 107Ae, but this is not limiting. For example, as shown in FIG. 9C , instead of providing a mirror inside housing 101A, a new optical member 131 (e.g., an optical lens or light-transmitting glass) may be fitted into wall surface 101Aa of housing 101A that faces the back side of phosphor wheel 107A, so that excitation light Lt that has passed through through-hole 107Ae passes through this optical member 131 and travels in a straight line. Alternatively, as shown in FIG. 9D , another new optical member 133 (e.g., a lens other than a mirror) may be further provided between the back side of phosphor wheel 107A and wall surface 101Aa inside housing 101A, so that excitation light Lt that has passed through through-hole 107Ae travels in a straight line.

[0045] (Embodiment 3) Hereinafter, a third embodiment will be described with reference to Fig. 10. The third embodiment is a projection-type image display device 1 that includes the phosphor wheel unit 100 of the first embodiment. Fig. 10 is a schematic diagram showing the overall configuration of the projection-type image display device 1 according to the third embodiment.

[0046] The projection-type image display device 1 of Figure 10 includes an illumination optical system 10 that supplies light, a light modulation unit 330 that modulates the light for each color, and a projection optical system 140 that projects the image light generated in the light modulation unit 330.

[0047] The illumination optical system 10 includes a plurality of blue semiconductor lasers (hereinafter referred to as "LDs") 201 and 202 and a plurality of lens groups 210 and 220. The lens group 210 is composed of a convex lens 211 and a concave lens 212, and is an afocal lens that re-collimates the light emitted from the LD 201. The lens group 220 is composed of a convex lens 221 and a concave lens 222, and is an afocal lens that re-collimates the light emitted from the LD 202. The LDs 201 and 202 emit color light in the blue region and output linearly polarized light. The LDs 201 and 202 are arranged so that the light they output becomes P-polarized light with respect to the incident surface of the dichroic mirror 206.

[0048] When the light emitted from the LD 201 passes through the convex lens 211 and the concave lens 212, it is shaped into parallel light with a desired beam width, and then passes through the diffusion plate 204 and reaches the dichroic mirror 206.

[0049] Dichroic mirror 206 transmits P-polarized blue light and reflects S-polarized blue light. Dichroic mirror 206 also reflects colored light containing green and red components. Since the blue light from LD 201 incident on dichroic mirror 206 is arranged to be P-polarized with respect to the incident surface of dichroic mirror 206, the light emitted from LD 201 passes through dichroic mirror 206 as is and travels in the direction of condenser lens group 230.

[0050] The blue light transmitted through dichroic mirror 206 enters condenser lens group 230. Condenser lens group 230 is made up of condenser lenses 231 and 232, which gradually condense the light and form a condensed spot near phosphor wheel 107 in phosphor wheel unit 100.

[0051] When excited by the spot light, phosphor layer 107b emits, for example, yellow light containing color light of green and red components. By rotating phosphor wheel 107 around rotation axis Ar, it is possible to suppress a temperature rise in phosphor layer 107b due to the blue excitation light and maintain stable fluorescence conversion efficiency. The color light of green and red components emitted from phosphor layer 107b is emitted as natural light with a random polarization state, is collected again by condenser lenses 232 and 231, converted into approximately parallel light, and then reflected by dichroic mirror 206. The light reflected by dichroic mirror 206 is incident on condenser lens 124 and collected on rod integrator 125.

[0052] On the other hand, when the light emitted from LD 202 passes through convex lens 221 and concave lens 222, it is shaped into approximately parallel light with a desired beam width, and then its direction is changed by mirror 203. After passing through diffuser 205, it reaches dichroic mirror 206. Similarly, the blue light of LD 202 that enters dichroic mirror 206 is arranged to be P-polarized with respect to the entrance surface of dichroic mirror 206, and therefore the light emitted from LD 202 passes through dichroic mirror 206 as it is, enters condenser lens 124, and is collected on rod integrator 125.

[0053] In this way, the yellow-gamut light containing green and red components emitted from phosphor wheel 250 and the blue-gamut light from LD 202 are combined by dichroic mirror 206 and enter rod integrator 125 as white light. These red, green, and blue-gamut light components exhibit good three primary colors, and by color combining these color lights, good white-balanced light emission characteristics can be obtained. In addition, by performing ON / OFF control with DMD 146, the color can be converted into a color with desired chromaticity coordinates.

[0054] Rod integrator 125 is a solid rod made of a transparent material such as glass. Rod integrator 125 generates light with a uniform light intensity distribution by internally reflecting incident light multiple times. Note that rod integrator 125 may also be a hollow rod whose inner wall is made of a mirror surface.

[0055] Lenses 126, 127, and 128 are relay lenses that approximately image the light emitted from rod integrator 125 onto DMD 146. The light emitted from rod integrator 125 is The light passes through lenses 126, 127, and 128, is reflected by mirrors 134 and 135, and then enters total internal reflection prism (hereinafter referred to as "TIR prism") 130. TIR prism 130 is formed of a prism having a substantially triangular prism shape, and totally reflects light that enters the prism at an angle equal to or greater than the critical angle. The light that enters TIR prism 130 from mirror 135 is totally reflected by this prism surface, and enters color separation / combining prism 340 of light modulation unit 330.

[0056] The light modulation unit 330 includes a color separating / combining prism 340 that separates the colors of incident light, and DMDs 146B, 146R, and 146G that serve as light modulation elements that modulate the separated light.

[0057] Color separation / combination prism 340 is composed of three prisms 340B, 340R, and 340G, with blue-reflecting dichroic coating layer 185 formed on the surface of prism 340B adjacent to prism 340R, and red-reflecting dichroic coating layer 186 formed on the surface of prism 340R adjacent to prism 340G. Prism 340B is a substantially triangular prism, and light incident from TIR prism 130 passes through prism 340B and then reaches blue-reflecting dichroic coating layer 185.

[0058] On the other hand, red-reflecting dichroic coating layer 186 is configured to reflect wavelengths corresponding to red light and transmit other light (green light and blue light). White light incident from TIR prism 130 and reaching blue-reflecting dichroic coating layer 185 is incident on blue-reflecting dichroic coating layer 185 provided on prism 340B within color separation / combining prism 340, and the blue-reflecting color light is reflected and then totally reflected on the surface of prism 340B to form an approximate image on DMD 146B.

[0059] On the other hand, the green and red color light components are incident on prism 340R after passing through blue-reflecting dichroic coating layer 185. Prism 340R is a prism having a substantially triangular prism shape, and the light incident from prism 340B passes through prism 340R and then reaches red-reflecting dichroic coating layer 186. Of the green and red color light components that have reached this prism, the red color light component is reflected by red-reflecting dichroic coating layer 186, and then is totally reflected by the surface of prism 340R due to the gap provided between prism 340R and prism 340B, and then forms a substantial image on DMD 146R.

[0060] The green light component that is not reflected by the red reflecting dichroic coating layer 186 is incident on the prism 340G. The prism 340R is a substantially rectangular prism, and after passing through the prism 340G, it forms a substantial image on the DMD 146G.

[0061] DMDs 146B, 146R, and 146G are modulated based on various control signals such as image signals to generate image light of different light intensities. Specifically, DMDs 146B, 146R, and 146G have multiple movable micromirrors. Each micromirror basically corresponds to one pixel. DMDs 146B, 146R, and 146G change the angle of each micromirror based on various control signals, thereby switching whether or not to direct reflected light toward the projection optical system 140.

[0062] The blue range color light reflected by DMD 146B re-enters prism 340B, is totally reflected on the surface of prism 340B, and then re-enters blue range reflecting dichroic coating layer 185. After the light reflected by blue range reflecting dichroic coating layer 185 passes through prism 340B, the light to be projected as an image (DMD-ON light) enters projection optical system 140 and is then emitted to projection surface 400, while the light not to be projected as an image (DMD-OFF light) does not enter projection optical system 140 and is output from prism 340B.

[0063] The red color light reflected by DMD 146R re-enters prism 340R, is totally reflected on the surface of prism 340R, and then re-enters red-reflecting dichroic coating layer 186. The light reflected by red-reflecting dichroic coating layer 186 passes through prism 340R and then re-enters blue-reflecting dichroic coating layer 185 provided on prism 340B. After passing through prism 340B, the light transmitted by blue-reflecting dichroic coating layer 185 passes through prism 340B, and the light to be projected as an image (DMD-ON light) enters projection optical system 140 and is then emitted to projection surface 400, while the light not to be projected as an image (DMD-OFF light) does not enter projection optical system 140 and is output from prism 340B.

[0064] The green color light reflected by DMD 146G re-enters prism 340G and then re-enters red-reflecting dichroic coating layer 186. The light transmitted by red-reflecting dichroic coating layer 186 passes through prism 340R and then re-enters blue-reflecting dichroic coating layer 185 provided on prism 340B. The light transmitted by blue-reflecting dichroic coating layer 185 passes through prism 340B, and then light to be projected as an image (DMD-ON light) enters projection optical system 140 and is emitted to projection surface 400, while light not to be projected as an image (DMD-OFF light) does not enter projection optical system 140 and is output from prism 340B.

[0065] Projection optical system 140 includes multiple projection lenses and magnifies the color-combined light emitted from color separation / combination prism 340. In this way, the DMD-ON light reflected by DMDs 146B, 146R, and 146G is color-combined again into blue, green, and red color lights within color separation / combination prism 340, and then reaches projection surface 400 through projection optical system 140 and is perceived as a full-color image. Note that the image includes both still images and moving images.

[0066] The projection-type image display device 1 including the phosphor wheel unit 100 can improve the cooling efficiency of the phosphor wheel unit 100, thereby increasing the amount of yellow range light obtained from the light emitted from the LD 201 and projecting images with higher brightness. Note that although the projection-type image display device 1 of the third embodiment is a 3DLP type projection-type image display device, it may also be a 1DLP type projection-type image display device.

[0067] (Other embodiments) As described above, the above-described embodiments have been described as examples of the technology in the present disclosure. However, the technology in the present disclosure is not limited to these, and can be applied to embodiments in which modifications, substitutions, additions, omissions, etc. are made. Furthermore, it is also possible to combine the components described in the above-described embodiments to create new embodiments.

[0068] In the above-described embodiment, the airflow inlet surface 113b and the airflow outlet surface 113c of the first heat exchanger 113 are arranged on the same plane, but this is not limited thereto. As in the first modified example shown in Fig. 11, in a modified phosphor wheel unit 100B, the airflow outlet surface 113Bc of the first heat exchanger 113B may be arranged so that the distance in the X direction from the rotation axis Ar of the phosphor wheel 107 is smaller than that from the airflow inlet surface 113Bb. In other words, the first heat exchanger 113B may be arranged so that the fins 113Ba of the first heat exchanger 113B have an L-shape and protrude closer to the motor 111 side than the exhaust port 109b side.

[0069] According to this configuration, the first heat exchanger 113B can be made larger than in the first embodiment, and therefore the cooling efficiency can be further improved.

[0070] In the above-described embodiment, the airflow inlet surface 113b of the first heat exchanger 113 is parallel to the opening surface of the exhaust port 109b of the wheel case 109. However, this is not limited to this. As shown in FIG. 12 , as long as the airflow inlet surface 113Cb of the first heat exchanger 113C faces the opening surface of the exhaust port 109b of the wheel case 109, the airflow inlet surface 113Cb does not have to be parallel to the opening surface of the exhaust port 109b of the wheel case 109. Even in this case, the airflow inlet surface 113Cb is disposed on an extension of the direction Da of the airflow restricted by the wheel case 109. This allows the high-speed airflow flowing out of the exhaust port 109b to flow into the airflow inlet surface 113Cb. This improves cooling efficiency. Furthermore, in the second modification, the first heat exchanger 113C has an airflow outlet surface 113Cd in addition to the airflow outlet surface 113Cc. This allows the air to reach the corners of the fins 113Ca, so that the heat of the gas can be conducted to the first heat exchanger 113C more efficiently.

[0071] In the above-described embodiment, the direction of the airflow flowing out of the wheel case 109 is restricted to a direction perpendicular to the direction of the rotation axis Ar of the phosphor wheel 107. However, this is not limiting. As in the third modified example shown in FIG. 13 , the direction of the airflow restricted by the wheel case 109D on a plane (XY plane) perpendicular to the extension direction of the base material 107f of the phosphor wheel 107 may be a direction intersecting the direction of the rotation axis Ar of the phosphor wheel 107. For example, the wheel case 109D may have an air outlet 109Dc extending in a direction at an angle θ on the plane (XY plane) perpendicular to the extension direction of the base material 107f of the phosphor wheel 107 with respect to a plane Sa perpendicular to the rotation axis Ar. As a result, the direction of the airflow restricted by the wheel case 109D flowing out of the exhaust port 109Db becomes a direction inclined with respect to the direction of the rotation axis Ar and enters the airflow inlet surface 113Db of the first heat exchanger 113D at an angle. On a plane (XY plane) perpendicular to the extension direction of the base material 107f of the phosphor wheel 107, the angle θ between the direction of the airflow restricted by the wheel case 109D and a plane Sa perpendicular to the rotation axis Ar of the phosphor wheel 107 is, for example, between 0 and 45 degrees. The heat exchanger 113D may be disposed at an angle with respect to the rotation axis Ar, as in the second modified example. This allows the airflow restricted by the wheel case 109D, which flows out from the exhaust port 109Db, to flow perpendicularly into the airflow inlet surface 113Db of the first heat exchanger 113D. The air outlet 109Dc of the wheel case 109D may partially extend perpendicular to the rotation axis Ar and partially extend in a direction forming an acute angle θ with respect to the plane Sa perpendicular to the rotation axis Ar.

[0072] In the above-described embodiment, wheel case 109 functions as a restricting member that restricts the direction of the airflow generated by the rotation of phosphor wheel 107, but this is not limiting. For example, instead of wheel case 109, a wall may be disposed between motor 111 and phosphor wheel 107, and the wall of housing 101 may be used as a restricting member.

[0073] In the above-described embodiment, fins 107d are arranged on rear surface 107c of phosphor wheel 107, but this is not limiting. Phosphor wheel 107 does not have to have fins 107d. Even if phosphor wheel 107 does not have fins 107d, airflow is generated in the radial direction of phosphor wheel 107 when phosphor wheel 107 rotates.

[0074] As described above, the embodiments have been described as examples of the technology of the present disclosure. For this purpose, the accompanying drawings and detailed description have been provided. Therefore, the components described in the accompanying drawings and detailed description may include not only components essential for solving the problem, but also components that are not essential for solving the problem in order to exemplify the above technology. Therefore, the fact that these non-essential components are described in the accompanying drawings or detailed description should not be interpreted as immediately indicating that these non-essential components are essential.

[0075] Furthermore, since the above-described embodiments are intended to illustrate the technology of the present disclosure, various modifications, substitutions, additions, omissions, etc. may be made within the scope of the claims or their equivalents.

[0076] (Outline of the embodiment) (1) The phosphor wheel unit of the present disclosure includes a phosphor wheel that converts incident light into fluorescent light, a motor that drives the phosphor wheel to rotate, a first heat exchanger having an airflow inlet surface on which a plurality of fins are arranged and through which some or all of the airflow generated by the rotation of the phosphor wheel flows, and a regulating member that regulates the direction of the airflow generated by the rotation of the phosphor wheel. On a plane perpendicular to the extension direction of base material 107f of the phosphor wheel, the angle between the direction of the airflow regulated by the regulating member and the direction perpendicular to the rotation axis of the phosphor wheel is between 0 and 45 degrees. The airflow inlet surface is located on an extension of the direction of the airflow regulated by the regulating member. The gas cooled by the heat exchanger returns to the phosphor wheel.

[0077] The direction of the radial airflow caused by the rotation of the phosphor wheel is restricted by a restricting member. The airflow inlet surface of the first heat exchanger is positioned on an extension of the restricted airflow direction, allowing the gas with the fastest flow rate to enter the first heat exchanger. This allows the gas to flow at a high rate throughout the entire space between the multiple fins of the first heat exchanger, thereby efficiently conducting heat from the gas. Furthermore, the gas cooled in this way returns to the phosphor wheel, improving the cooling efficiency of the phosphor wheel.

[0078] (2) In the phosphor wheel unit of (1), the direction of the airflow restricted by the restricting member is perpendicular to the direction of the rotation axis of the phosphor wheel on a plane perpendicular to the extension direction of the base material 107f of the phosphor wheel. As a result, the airflow is not restricted in the direction of the rotation axis Ar, so that the pressure loss of the airflow at the restricting member can be reduced and the airflow can be discharged, thereby suppressing a decrease in the speed of the airflow.

[0079] (3) In the phosphor wheel unit of (1) or (2), the direction of the airflow restricted by the restricting member is parallel to the normal direction of the airflow inlet surface of the first heat exchanger.

[0080] (4) In any one of the phosphor wheel units (1) to (3), a wheel case that houses the phosphor wheel is provided as a regulating member, and the wheel case has an intake port through which gas flows in and an exhaust port through which the gas that has cooled the phosphor wheel is exhausted.

[0081] (5) In the phosphor wheel unit of (4), the direction of the airflow restricted by the wheel case is parallel to the normal direction of the opening surface of the exhaust port.

[0082] (6) In the phosphor wheel unit of (4) or (5), the normal direction of the opening surface of the exhaust port and the rotation axis direction of the phosphor wheel are perpendicular to each other.

[0083] (7) In any one of the phosphor wheel units (4) to (6), the normal direction of the airflow inlet surface and the normal direction of the opening surface of the exhaust port are parallel to each other.

[0084] (8) In any one of the phosphor wheel units (4) to (7), the longitudinal length of the exhaust port of the wheel case is equal to the length of the air flow inlet surface in the direction in which the multiple fins are arranged in the opposing first heat exchanger.

[0085] (9) The phosphor wheel unit of any one of (1) to (8) further comprises a wall portion disposed at a position where the gas that flows into the air flow inlet surface of the first heat exchanger and passes through the first heat exchanger hits the wall portion. The first heat exchanger has an air flow outlet surface from which the gas cooled by the first heat exchanger flows out. The gas that flows into the first heat exchanger from the air flow inlet surface hits the wall portion and flows out from the air flow outlet surface.

[0086] (10) In the phosphor wheel unit of (9), the airflow inlet surface and the airflow outlet surface of the first heat exchanger are arranged on the same plane.

[0087] (11) In the phosphor wheel unit of (9), the airflow outlet surface of the first heat exchanger is arranged closer to the rotation axis of the phosphor wheel than the airflow inlet surface.

[0088] (12) In the phosphor wheel unit of any one of (1) to (11), the phosphor wheel has fins on a rear surface opposite to the light incident surface.

[0089] (13) The phosphor wheel unit according to any one of (1) to (12), further comprising: a housing that houses the phosphor wheel, the motor, and the first heat exchanger; and a second heat exchanger that is disposed outside the housing and has a plurality of fins. The first heat exchanger and the second heat exchanger are connected by a thermally conductive member.

[0090] (14) The phosphor wheel unit of (13) is provided with a fan that sends cooling air to the second heat exchanger.

[0091] (15) In the phosphor wheel unit of any one of (1) to (14), the phosphor wheel has holes that allow incident light to pass through.

[0092] (16) In the phosphor wheel unit of (15), the phosphor wheel unit includes an optical member on the back side opposite to the incident surface of the phosphor wheel, for receiving light that has passed through the holes in the phosphor wheel.

[0093] (17) In the phosphor wheel unit of (16), the optical member is a mirror.

[0094] (18) A projection-type image display device according to the present disclosure includes any one of the phosphor wheel units (1) to (17). [Industrial Applicability]

[0095] The present disclosure is applicable to a phosphor wheel unit that receives light and emits fluorescent light, and to a projection-type image display device including the same. [Explanation of symbols]

[0096] 100, 100A phosphor wheel unit 101, 101A housing 101a side wall 103 Second heat exchanger 103a Fin 105 Fan 107, 107A phosphor wheel 107a, 107Aa entrance plane 107b, 107Ab Phosphor layer 107c back 107d Fin 107Ae through hole 109, 109A, 109D Wheel Cases 109a, 109Aa intake 109b, 109Db exhaust port 111 Motor 113, 113B, 113C, 113D First heat exchanger 113a, 113Ba, 113Ca Fin 113b, 113Bb, 113Cb, 113Db Airflow inlet surface 113c, 113Bc, 113Cc, 113Cd Airflow outlet surface 115 Heat conducting material 117 Convex Lens 121, 123 Mirror Ar rotation axis Lt excitation light

Claims

1. a phosphor wheel that emits fluorescent light from incident light; a motor that rotates and drives the phosphor wheel; a first heat exchanger having an airflow inlet surface on which a plurality of fins are arranged and into which a part or all of the airflow generated by the rotation of the phosphor wheel flows; a restricting member that restricts the direction of the airflow generated by the rotation of the phosphor wheel; a wall portion disposed at a position where the gas that has flowed into the air flow inlet surface and passed through the first heat exchanger hits the wall portion; an angle between a direction of the airflow regulated by the regulating member and a direction perpendicular to a rotation axis of the phosphor wheel on a plane perpendicular to an extending direction of a base material of the phosphor wheel is equal to or greater than 0 degrees and equal to or less than 45 degrees; the airflow inlet surface is disposed on an extension of the direction of the airflow regulated by the regulating member, the first heat exchanger has an airflow outlet surface through which the gas cooled by the first heat exchanger flows out; the airflow inlet surface and the airflow outlet surface are disposed on substantially the same plane, a direction in which the fins of the first heat exchanger are arranged intersects with a rotation axis of the phosphor wheel and with a normal to the air inlet surface; the gas that has flowed into the first heat exchanger from the air flow inlet surface passes between the fins, hits the wall portion, passes between the fins again, flows out from the air flow outlet surface, and returns to the phosphor wheel; Phosphor wheel unit.

2. the direction of the airflow regulated by the regulating member is a direction perpendicular to a rotation axis direction of the phosphor wheel on a plane perpendicular to an extension direction of a base material of the phosphor wheel; The phosphor wheel unit according to claim 1 .

3. the direction of the airflow regulated by the regulating member is parallel to the normal direction of the airflow inlet surface; The phosphor wheel unit according to claim 1 or 2.

4. a wheel case that houses the phosphor wheel as the restricting member; The wheel case has an intake port through which gas flows in and an exhaust port through which gas that has cooled the phosphor wheel is exhausted. The phosphor wheel unit according to claim 1 .

5. The direction of the airflow restricted by the wheel case is parallel to the normal direction of the opening surface of the exhaust port. The phosphor wheel unit according to claim 4 .

6. a normal direction of an opening surface of the exhaust port and a rotation axis direction of the phosphor wheel are perpendicular to each other; The phosphor wheel unit according to claim 4 or 5.

7. a normal direction of the air flow inlet surface and a normal direction of the opening surface of the exhaust port are parallel to each other; The phosphor wheel unit according to any one of claims 4 to 6.

8. a longitudinal length of the exhaust port of the wheel case is equal to a length of the air flow inlet surface in a direction in which the plurality of fins are arranged in the opposing first heat exchanger; The phosphor wheel unit according to any one of claims 4 to 7.

9. a normal direction of the airflow inlet surface and a normal direction of at least a part of the airflow outlet surface are parallel to each other; The phosphor wheel unit according to claim 1 .

10. the airflow outlet surface is disposed closer to the rotation axis of the phosphor wheel than the airflow inlet surface. The phosphor wheel unit according to claim 1 .

11. the phosphor wheel has fins on a back surface opposite to the light incident surface; The phosphor wheel unit according to any one of claims 1 to 10.

12. a housing that accommodates the phosphor wheel, the motor, and the first heat exchanger; a second heat exchanger disposed outside the housing and having a plurality of fins; The first heat exchanger and the second heat exchanger are connected by a heat conduction member. The phosphor wheel unit according to any one of claims 1 to 11.

13. a fan for blowing cooling air to the second heat exchanger; The phosphor wheel unit of claim 12.

14. The phosphor wheel has holes that allow incident light to pass through. The phosphor wheel unit according to any one of claims 1 to 13.

15. the phosphor wheel unit includes an optical member on a back surface side opposite to the light incidence surface of the phosphor wheel, the optical member receiving the light that has passed through the hole of the phosphor wheel; The phosphor wheel unit of claim 14.

16. The optical member is a mirror. The phosphor wheel unit of claim 15.

17. 17. A phosphor wheel unit according to claim 1, Projection-type image display device.

Images