JP2019003760A - Lighting system and projection type display device - Google Patents

Abstract

To solve a problem that a tabular fin arranged for cooing to a rotor to prevent overheat of a fluorescent material in a conventional light source for projection type display device using the rotor coated by the fluorescent material makes loud noise by round tile sound and increases cost because production is not simple.SOLUTION: Spiral uneven structure is arranged on side surface of a cylindrical part 102a of a rotor 102. When the rotor rotate at light emitting, air current AIR is generated by the spiral uneven structure and cools a fluorescent material 103, but noise by round tile sound is suppressed to low-level in comparison with a tabular fin. It can be manufactured in low cost because the manufacture is easier than the tabular fin.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a light source device including a rotating body covered with a phosphor, and a projection display device using the light source device.

  In recent years, semiconductor lasers that output short-wavelength light with high luminous efficiency have been developed. A phosphor is excited by the output light of such a semiconductor laser, and the wavelength-converted light is used as a light source for a projection display device.

The phosphor may be fixed at a certain place and irradiated with excitation light, but if the excitation light always irradiates the same point of the phosphor, the temperature rises locally, and the luminous efficiency decreases, Furthermore, material deterioration may occur. For this reason, a light source is often used in which a phosphor is provided on the main surface of a rotating disk so that excitation light does not constantly irradiate the same point of the phosphor.
For example, Patent Document 1 describes a light source configured such that heat is not concentrated on one point of a fluorescent plate by irradiating a rotating fluorescent plate with output light of an excitation light source.

When a light source with higher brightness is required, it has been attempted not only to rotate the fluorescent plate to prevent concentration of heat storage but also to provide a structure that actively dissipates heat to suppress deterioration of the phosphor.
For example, Patent Document 2 describes a light source in which a heat dissipating fin is provided on a wheel provided with a phosphor.

JP 2012-78488 A JP 2012-13897 A

  In the light source described in Patent Document 2, air is diffused by centrifugal force when the wheel rotates by providing plate-like fins 4b and 4c as shown in FIGS. 7 (a), (b) and (c). Thus, a cooling effect can be obtained.

  However, as described in paragraph [0021] of Patent Document 2, when such plate-like fins are used, there is a problem that noise due to wind noise increases. Whether for home use or business use, projection projectors have great expectations for noise reduction, and the generation of noise due to wind noise has been a problem.

  Further, the plate-like fin structure shown in FIGS. 7A, 7B, and 7C has a problem that it is not easy to manufacture. If the fin shape accuracy is low, not only will the wind noise increase, but the weight balance will be biased and vibration will occur during rotation, but it is not easy to accurately mold the plate-like fin part, Manufacturing costs tend to be high.

Also, since the plate-shaped part of the fin is easily deformed by external force, it may cause unintended deformation if it touches the fin when transporting parts or assembling a projection display device. I had to pay.
Therefore, a light source that is easy to manufacture and handle while suppressing the noise due to wind noise while suitably providing a cooling effect has been expected.

The present invention is a light source device for a projection display device, and includes a rotating body made of metal, a phosphor coated on the rotating body, and excitation that outputs excitation light for exciting the phosphor. A light source;
And the rotating body has a concavo-convex structure extending spirally along the side surface.
Moreover, this invention is a projection type display apparatus provided with the said light source device, a light modulation element, and a projection lens.

  ADVANTAGE OF THE INVENTION According to this invention, the noise by a wind noise can be suppressed, but it can provide the light source which manufacture and handling are easy, although there exists suitably a cooling effect. In addition, it is possible to provide a low-noise and high-brightness projection display device provided with such a light source device.

(A) Sectional drawing of the rotary body of 1st embodiment. (B) The top view of the rotary body of 1st embodiment. The block diagram of the projection type display apparatus provided with the light source device of 1st embodiment. (A) Sectional drawing of the rotary body of 2nd embodiment. (B) The top view of the rotary body of 2nd embodiment. (C) The external view of the rotary body of 2nd embodiment. (A) Sectional drawing of the rotary body of 3rd embodiment. (B) The top view of the rotary body of 3rd embodiment. (A) Sectional drawing of the rotary body of 4th embodiment. (B) The top view of the rotary body of 4th embodiment. (A) Sectional drawing of the rotary body of 5th embodiment. (B) The top view of the rotary body of 5th embodiment. The external view of the rotary body with the conventional plate-shaped fin.

[First embodiment]
With reference to drawings, the light source device for projection type display apparatuses which is 1st embodiment of this invention, and the projection type display apparatus provided with the same are demonstrated. First, the rotating body included in the light source device will be described, and then the entire projection display device including the light source device will be described.

(Rotating body of light source device)
1A and 1B, reference numeral 101 denotes a motor, 102 denotes a rotating body, and 103 denotes a phosphor.
FIG. 1A is a cross-sectional view of the rotating body 102 cut along the rotation axis, and FIG. 1B is a front view of the rotating body 102. In FIG. 1A, the cross section of the inside of the motor 101 is omitted.

  The rotating body 102 includes a cylindrical portion 102a, a disc-shaped portion 102b, an annular inclined portion 102c, and an axial center portion 102d. The cylindrical portion 102a and the disc-shaped portion 102b are connected via an annular slope portion 102c, and the surface of the annular slope portion 102c is covered with a phosphor 103.

  As shown in FIG. 1B, the surface PR of the red light emitting phosphor, the region PG provided with the green light emitting phosphor, and the yellow light emitting phosphor are provided on the surface of the annular slope portion 102c. Four band-like regions are provided, the applied region PY and the reflection region RB that reflects the excitation light. Each region is arranged on an arc centered on the rotation axis RA.

As the rotating body 102 rotates, the region PR, the region PG, and the region PY are sequentially irradiated with excitation light, and emit red, green, and yellow fluorescence, respectively. Further, when the reflection region RB is irradiated with excitation light (blue laser light), the blue light is reflected by the rotating body 102. The surface of the annular slope portion 102c is mirror-finished so that the fluorescence emitted from the regions PR, PG, and PY can be effectively extracted, or the blue laser light is reflected with high efficiency in the reflection region RB. Is desirable.
The shaft center portion 102d of the rotating body 102 is fixed to the rotating shaft of the motor 101, and the rotating body 102 rotates following the motor rotating shaft. The rotating body 102 rotates at a high speed so that the projection display device can display a color image at a high frame rate. Specifically, for example, the rotating body 102 is 7200 rpm to support a color image display of 120 screens per second. Rotate.

  The rotating body 102 is formed of a metal material having high thermal conductivity and reflectance. For example, aluminum or an aluminum alloy is preferably used. The cylindrical part 102a, the disk-like part 102b, the annular sloped part 102c, and the shaft center part 102d can be manufactured separately and then joined. However, in order to reduce the manufacturing cost, a bulk base material is used. It is preferable to mold each part by processing.

  In the present embodiment, a groove formed in a spiral shape is provided on the inner surface of the cylindrical portion 102a. It can be said that a groove (concave portion) is formed if the surface closest to the rotation axis among the cylindrical inner surfaces is used as a reference, and a ridge line (convex portion) extending spirally is formed if the bottom of the recess is used as a reference. In other words, Alternatively, it may be said that a concavo-convex structure extending in a spiral shape is formed.

  In the present embodiment, a spiral groove that is the same as or similar to a screw groove formed on the inner surface of a general nut is formed as the spiral concavo-convex structure. The spiral groove is configured so that the ratio of the rotation angle to the distance traveled in the direction along the rotation axis RA, that is, the pitch is constant, and the spiral winding rotates at least one round of the inner surface of the cylinder, that is, 360 degrees or more. It extends to do. When rotating the rotating body, the spiral groove induces an air flow, but by adopting a spiral with a constant pitch as described above, the induced air flow becomes uniform along the rotation axis direction, Generation of turbulence is suppressed, which is advantageous for reducing noise. In addition, since an air flow is generated inside the cylindrical portion 102a, the rotating body itself functions as a sound insulating material, so that noise can be suppressed low.

  The direction of the spiral may be a direction that turns clockwise when it moves away from the motor 101, or a direction that turns counterclockwise. However, the direction of the air flow induced by the rotation at the time of light emission flows to the phosphor side. Is preferred. In other words, the rotation direction of the rotating body may be set in the direction in which the air flow induced by the spiral concavo-convex structure flows to the phosphor side. In the present embodiment, when the rotating body rotates during light emission, the air flows toward the inner surface of the annular slope portion 102c provided with the phosphor 103, as shown as an air flow AIR in FIG. Therefore, the phosphor can be efficiently cooled.

  The spiral groove of this embodiment can be easily formed by cutting the inner surface of the cylindrical portion 102a of the rotating body 102 using, for example, a threading tap.

  As described above, the light source of the present embodiment can efficiently cool the phosphor using the rotating body provided with the spiral groove. Generation of turbulent flow is suppressed by keeping the pitch of the spiral provided on the inner surface of the cylindrical portion constant. For example, noise caused by wind noise can be kept low even when rotating at a high speed of 7200 rpm. In addition, the rotating body according to the present embodiment is easier to manufacture and handle than a rotating body provided with plate-like fins, and the cost can be reduced.

Next, a light source device including the above-described rotating body and a projection display device using the light source device as an illumination light source will be described.
(Light source device)
In FIG. 2, a portion surrounded by a dotted line is the light source device 200 including the above-described rotating body 102.
First, the excitation light source unit 211 includes a plurality of blue laser light sources arranged in an array and a plurality of collimating lenses arranged corresponding to each of the blue laser light sources. The blue laser light source and the collimating lenses are modularized. ing. The blue laser light source used for the light source unit is, for example, a semiconductor laser that emits S-polarized light having a wavelength of 440 nm.

  Each module of the excitation light source unit 211 includes a light emitting element array in which blue laser light sources are arranged in a matrix of 2 × 4. However, the scale of the matrix arrangement included in one module is not limited to this example. A larger-scale matrix arrangement may be used, or a matrix arrangement having the same vertical and horizontal dimensions may be used. The light output from each laser light source is emitted from the excitation light source unit 211 as a substantially parallel light beam by the action of the collimating lens.

  The S-polarized blue laser light emitted from the excitation light source unit 211 is reflected by the polarization beam splitter 213 through the excitation light source side condensing lens 212 and is provided on the inclined surface of the rotating body 102 by the phosphor side condensing lens 215. Focused on the body. As described above, phosphors that emit red, green, and yellow light are disposed in the area irradiated with the excitation light on the inclined surface of the rotating body 102. The polarization beam splitter 213 reflects blue excitation light, which is S-polarized light, but fluorescence that is not polarized, and P-polarized blue light that is reflected by the rotating body 102 and returns via the quarter-wave plate 214. It is a mirror having selectivity that allows light to pass through. The fluorescence emitted from the phosphor is collected by the phosphor-side condenser lens 215, passes through the polarization beam splitter 213, and is emitted toward the relay lens 210.

(Projection type display device)
2 uses the light source device 200 described above as an illumination light source, and further includes a relay lens 210, a color selection wheel 220, a motor 221, a light tunnel 240, an illumination lens 250, a light modulation device 260, A prism 271, a prism 272, and a projection lens 280 are provided. Furthermore, a projection screen 290 may be provided.

  The relay lens 210 is a lens for setting the light emitted from the light source device 200 to a predetermined NA so as to match the F number of the projection lens 280 and condensing it at the entrance of the light tunnel 240. The relay lens does not necessarily have to be composed of a single lens. Further, when the NA is sufficient, it may not be provided.

The color selection wheel 220 is a plate-like rotator that is driven by a motor 221 and rotates about a rotation axis Ac. Each of the R, G, and Y color filters and a fan-shaped notch (light transmission for transmitting blue light) are used. Part). The color filters for each color are provided to cut light in unnecessary wavelength ranges and increase the color purity of display light. However, blue light is a laser beam with high color purity, and it is not necessary to provide a filter.
The rotating body 102 to which the phosphor is applied and the color selection wheel 220 rotate in synchronization. The R filter emits light when the former red phosphor emits light, and the G filter when the green phosphor emits light. The rotation timing of the filter is adjusted so that the Y filter is positioned on the optical path when the yellow phosphor emits light, and the light transmitting portion is positioned on the optical path when the blue excitation light is reflected. In addition, when the emission color purity of the phosphor is sufficiently high, there may be a case where the color selection wheel may not be provided.

The illumination lens 250 is a lens that shapes the light propagated through the light tunnel 240 into a light beam suitable for illuminating the light modulation device 260. Consists of one or more lenses.
The prism 271 and the prism 272 together constitute a TIR prism (internal total reflection prism). The TIR prism causes the illumination light to be totally internally reflected, enter the light modulation device 260 at a predetermined angle, and transmit the reflected light modulated by the light modulation device 260 toward the projection lens 280.

The light modulation device 260 is an element that modulates incident light based on a video signal, and uses a DMD provided with micromirror devices in an array. However, other reflective light modulation devices such as a reflective liquid crystal device can also be used.
The projection lens 280 is a lens for projecting the light modulated by the light modulation device 260 as an image. Consists of one or more lenses.

  The projection screen 290 is used when configuring a rear projection type display device. Further, although it is often installed also in the case of the front projection type, it is not always necessary to provide it when the user projects on an arbitrary wall surface or the like.

Next, the overall operation of the projection display device will be described.
The illumination light emitted from the light source device with suppressed color unevenness enters the prism 271 of the TIR prism via the relay lens 210, the color selection wheel 220, the light tunnel 240, and the illumination lens 250. The light reflected by the total reflection surface of the prism 271 enters the light modulation device 260 at a predetermined angle.
The light modulation device 260 has a micromirror device provided in an array, and drives the micromirror device in accordance with each color component signal of the video in synchronization with the switching of the color of the illumination light, and converts the video light into a prism. Reflects at a predetermined angle toward 271. The image light passes through the prism 271 and the prism 272, is guided to the projection lens 280, and is projected onto the projection screen 290.

  Since the projection type display device of this embodiment can illuminate the light modulation element using a light source device with high output and high quietness, it is possible to display a high brightness image with low noise.

[Second Embodiment]
A second embodiment including a rotating body having a configuration different from that of the first embodiment will be described.
(Rotating body of light source device)
In FIGS. 3A, 3B, and 3C, 301 is a motor, 302 is a rotating body, and 303 is a phosphor.

  3A is a cross-sectional view of the rotating body 302 cut along the rotation axis, FIG. 3B is a front view of the rotating body 302, and FIG. 3C is an external view of the rotating body 302. It is. In FIG. 3A, the cross section of the interior of the motor 301 is omitted.

  The rotating body 302 includes a cylindrical portion 302a, a disc-shaped portion 302b, and an axial center portion 302c. The cylindrical portion 302a and the shaft center portion 302c are connected via a disc-shaped portion 302b. In order to reduce the weight of the rotating body 302 and improve the air cooling efficiency, a concave portion 304 and a concave portion 305 are provided with a disc-shaped portion 302b interposed therebetween.

  A band-shaped phosphor 303 is provided on the outer surface on the tip side of the cylindrical portion 302a. Although not shown, the band-like phosphor 303 includes a region PR to which a red light-emitting phosphor is applied, a region PG to which a green light-emitting phosphor is applied, and a region PY to which a yellow light-emitting phosphor is applied. A reflection region RB that reflects excitation light is also provided on the outer side surface adjacent to the band-shaped phosphor 303.

As the rotator 302 rotates, the region PR, the region PG, and the region PY are sequentially irradiated with excitation light, and emit red, green, and yellow fluorescence, respectively. Further, when the reflection region RB is irradiated with excitation light (blue laser light), the blue light is reflected by the rotating body 302. The surface of the outer surface on the front end side of the cylindrical portion 302a can effectively extract the fluorescence emitted in the region PR, the region PG, and the region PY, or can reflect the blue laser light with high efficiency in the reflection region RB. It is desirable to mirror finish.
The axial center portion 302c of the rotating body 302 is fixed to the rotating shaft of the motor 301, and the rotating body 302 rotates following the motor rotating shaft. The rotator 302 rotates at a high speed so that the projection display device can display a color image at a high frame rate. Specifically, the rotator 302 is, for example, 7200 rpm in order to support a color image display of 120 screens per second. Rotate.

  The rotating body 302 is formed of a metal material having high thermal conductivity and reflectance. For example, aluminum or an aluminum alloy is preferably used. The cylindrical portion 302a, the disc-shaped portion 302b, and the shaft center portion 302c can be separately manufactured and then joined, but in order to reduce the manufacturing cost, each part is processed by processing a bulk base material. Should be molded.

  In the present embodiment, a groove 302d formed in a spiral shape is provided on the outer surface of the cylindrical portion 302a. It can be said that a groove (concave portion) is formed if the surface farthest from the rotation axis among the outer surfaces of the cylinder is used as a reference, and a spirally extending ridge line (convex portion) is formed if the bottom of the recess is used as a reference. In other words, Alternatively, it may be said that a concavo-convex structure extending in a spiral shape is formed.

  In this embodiment, as shown in the external view of FIG. 3C, a spiral groove that is the same as or similar to a screw groove formed on a general bolt is used as the spiral groove 302d. The spiral groove 302d is configured such that the ratio of the rotation angle to the distance traveled in the direction along the rotation axis RA, that is, the pitch is constant, and the spiral winding is at least one round (360 degrees) around the outer surface of the cylinder. It extends so as to rotate. When the rotating body is rotated, the spiral groove induces an air flow. However, as described above, by adopting a spiral with a constant pitch, the induced air flow becomes uniform along the rotation axis direction, and turbulence occurs. This is because the generation of flow is suppressed and it is advantageous for reducing noise.

  The direction of the helix may be a direction that turns clockwise when moving in a direction away from the motor 301, or a direction that turns counterclockwise, but the direction in which the air flow induced by rotation during light emission flows to the phosphor side Is preferred. That is, in this embodiment, when the rotating body rotates during light emission, as shown as AIR in FIG. 3A, the air flows toward the outer surface on the front end side where the phosphor 303 is provided. Therefore, the phosphor 303 can be efficiently cooled.

  The spiral groove of this embodiment can be easily formed by cutting the outer surface of the cylindrical portion 302a of the rotating body 302 using, for example, a threading tap.

  As described above, the light source of the present embodiment can efficiently cool the phosphor using the rotating body provided with the spiral groove. The generation of turbulent flow is suppressed by keeping the pitch of the spiral provided on the inner surface of the cylindrical portion constant, and for example, noise caused by wind noise can be kept low even when rotating at a high speed of 7200 rpm. The rotating body of the present embodiment is easier to manufacture and handle than a conventional rotating body provided with plate-like fins, and the cost can be reduced.

  Similarly to the light source device of the first embodiment, the light source device including the rotating body of the present embodiment can be used for the projection display device described with reference to FIG. Since the configuration is basically the same, the description thereof will be omitted, but since the light source device of the present embodiment is provided with a phosphor on the side surface of the rotating body, the rotation axis RA of the rotating body is along the Y axis in FIG. The difference is that the layout is oriented. Since the projection type display device of this embodiment can illuminate the light modulation element using a light source device with high output and high quietness, it is possible to display a high brightness image with low noise.

[Third embodiment]
A third embodiment including a rotating body having a configuration different from the first embodiment and the second embodiment will be described.
(Rotating body of light source device)
4A and 4B, 401 is a motor, 402 is a rotating body, and 403 is a phosphor.

FIG. 4A is a cross-sectional view of the rotator 402 viewed along the rotation axis, and FIG. 4B is a front view of the rotator 402. In FIG. 4A, the cross section of the inside of the motor 401 is omitted.

  The rotating body 402 includes a cylindrical portion 402a, a disc-shaped portion 402b, and an axial center portion 402c. The cylindrical portion 402a and the axial center portion 402c are connected via a disc-shaped portion 402b. In order to reduce the weight of the rotating body 402 and improve the air cooling efficiency, a concave portion 404 and a concave portion 405 are provided with a disc-shaped portion 402b interposed therebetween.

  A band-shaped phosphor 403 is provided on the annular portion of the end surface on the distal end side of the cylindrical portion 402a. As shown in FIG. 4B, the band-shaped phosphor 403 includes a region PR to which a red light-emitting phosphor is applied, a region PG to which a green light-emitting phosphor is applied, and a region to which a yellow light-emitting phosphor is applied. Includes PY. In the annular portion, a reflection region RB that reflects excitation light is provided along with the band-shaped phosphor.

As the rotator 402 rotates, the region PR, region PG, and region PY are sequentially irradiated with excitation light, and emit red, green, and yellow fluorescence, respectively. In addition, when the reflection region RB is irradiated with excitation light (blue laser light), the blue light is reflected by the rotating body 402. The surface of the end surface on the front end side of the cylindrical portion 402a is a mirror surface so that the fluorescence emitted from the region PR, the region PG, and the region PY can be effectively extracted or the blue laser light is reflected with high efficiency in the reflection region RB. It is desirable to process.
An axial center portion 402c of the rotating body 402 is fixed to the rotating shaft of the motor 401, and the rotating body 402 rotates following the motor rotating shaft. The rotator 402 rotates at a high speed so that the projection display device can perform color image display at a high frame rate. Specifically, the rotator 402 is, for example, 7200 rpm to support color image display of 120 screens per second. Rotate.

  The rotating body 402 is made of a metal material having high thermal conductivity and reflectance. For example, aluminum or an aluminum alloy is preferably used. The cylindrical part 402a, the disk-like part 402b, and the shaft center part 402c can be manufactured separately and then joined. However, in order to reduce the manufacturing cost, each part is processed by processing a bulk base material. Should be molded.

  In this embodiment, the grooves 402d and 402e formed in a spiral shape are provided on both the outer surface and the inner surface of the cylindrical portion 402a. Alternatively, it may be said that a concavo-convex structure extending in a spiral shape is formed.

  In this embodiment, a spiral groove that is the same as or similar to a screw groove formed on a general bolt is used as the spiral groove 402d. Further, as the spiral groove 402e, a spiral groove that is the same as or similar to a screw groove formed on a general nut is used.

  The spiral grooves 402d and 402e are configured such that the ratio of the rotation angle to the distance traveled in the direction along the rotation axis RA, that is, the pitch is constant, and the spiral winding is at least one round of the inner or outer surface of the cylinder. It extends so as to rotate more than (360 degrees). When the rotating body is rotated, the spiral groove induces an air flow. However, as described above, by adopting a spiral with a constant pitch, the induced air flow becomes uniform along the rotation axis direction, and turbulence occurs. This is because the generation of flow is suppressed and it is advantageous for reducing noise.

  The direction of the helix may be a direction that turns clockwise when moving in a direction away from the motor 401 or a direction that turns counterclockwise, but the air flow induced by the rotation at the time of light emission causes the cylindrical portion 402a to rotate. The direction which flows to the phosphor side at the tip is preferable. That is, in the present embodiment, when the rotating body rotates during light emission, as shown as AIR in FIG. 4A, air is configured to flow toward the tip side where the phosphor is provided. It is possible to cool the phosphor efficiently.

  The spiral groove of this embodiment can be easily formed by cutting the outer surface and the inner surface of the cylindrical portion 402a of the rotating body 402 using, for example, a cutting tool for thread cutting.

  As described above, the light source of the present embodiment can efficiently cool the phosphor using the rotating body provided with the spiral groove. The generation of turbulent flow is suppressed by making the pitch of the spirals provided on the inner and outer surfaces of the cylindrical portion constant, and for example, noise caused by wind noise can be kept low even when rotating at a high speed of 7200 rpm. In addition, the rotating body according to the present embodiment is easier to manufacture and handle than a rotating body provided with plate-like fins, and the cost can be reduced.

  The light source device provided with the rotating body of the present embodiment can be used for the projection display device described with reference to FIG. 2, similarly to the light source device of the first embodiment. Since the configuration is basically the same, the description is omitted. However, since the light source device of the present embodiment is provided with the phosphor on the cylindrical partial end surface (rotary body front surface) of the rotating body, the rotation axis RA of the rotating body is The difference is that it is laid out so as to be oriented along the X axis in FIG. Since the projection type display device of this embodiment can illuminate the light modulation element using a light source device with high output and high quietness, it is possible to display a high brightness image with low noise.

[Fourth embodiment]
A fourth embodiment, which differs from the third embodiment in the method of fixing the rotating body to the motor, will be described.
5A and 5B, reference numeral 501 denotes a motor, 502 denotes a rotating body, and 503 denotes a phosphor.
FIG. 5A is a cross-sectional view of the rotating body 502 viewed along the rotation axis, and FIG. 5B is a front view of the rotating body 502. In FIG. 5A, the cross section of the inside of the motor 501 is omitted.

In the third embodiment, the shaft center portion 402c of the rotating body 402 is fixed to the rotating shaft of the motor 401. However, in this embodiment, the rotating shaft of the motor is provided with a motor hub 501H at the tip. Is fixed to the motor hub 501H.
The rotating body 502 includes a cylindrical portion 502a, a disk-like portion 502b, and an axial center portion 502c. The cylindrical portion 502a and the shaft center portion 502c are connected via a disc-shaped portion 502b.
Although not shown in the sectional view of FIG. 5A, the disk-like portion 502b is fixed to the motor hub 501H with four screws 504 as seen in the front view of FIG. 502 rotates following the rotation of the motor. The rotating body 502 rotates at a high speed so that the projection display device can display a color image at a high frame rate. Specifically, for example, the rotating body 502 is 7200 rpm in order to correspond to a color image display of 120 screens per second. Rotate.

  A band-shaped phosphor 503 is provided on the annular portion of the end surface on the distal end side of the cylindrical portion 502a. As shown in FIG. 5B, the band-shaped phosphor 503 includes a region PR to which a red light-emitting phosphor is applied, a region PG to which a green light-emitting phosphor is applied, and a region to which a yellow light-emitting phosphor is applied. Includes PY. In the annular portion, a reflection region RB that reflects excitation light is provided along with the band-shaped phosphor.

  As the rotator 502 rotates, the region PR, the region PG, and the region PY are sequentially irradiated with excitation light, and emit red, green, and yellow fluorescence, respectively. Further, when the reflection region RB is irradiated with excitation light (blue laser light), the blue light is reflected by the rotating body 502. The surface of the end surface on the tip side of the cylindrical portion 502a is a mirror surface so that the fluorescence emitted from the region PR, the region PG, and the region PY can be effectively extracted or the blue laser light is reflected with high efficiency in the reflection region RB. It is desirable to process.

  The rotating body 502 is formed of a metal material having high thermal conductivity and reflectance. For example, aluminum or an aluminum alloy is preferably used. The cylindrical portion 502a, the disc-shaped portion 502b, and the shaft center portion 502c can be manufactured after being manufactured separately, but in order to reduce the manufacturing cost, each part is processed by processing a bulk base material. Should be molded.

  In this embodiment, grooves 502d and 502e formed in a spiral shape are provided on both the outer surface and the inner surface of the cylindrical portion 502a. Alternatively, it may be said that a concavo-convex structure extending in a spiral shape is formed.

  In this embodiment, a spiral groove that is the same as or similar to a screw groove formed on a general bolt is used as the spiral groove 502d. Further, as the spiral groove 502e, a spiral groove that is the same as or similar to a screw groove formed in a general nut is used. The spiral grooves 502d and 502e are configured such that the ratio of the rotation angle to the distance traveled in the direction along the rotation axis RA, that is, the pitch is constant, and the spiral winding of the spiral groove at least 1 on the inner surface or outer surface of the cylinder. It extends to rotate more than the circumference (360 degrees). When the rotating body is rotated, the spiral groove induces an air flow. However, as described above, by adopting a spiral with a constant pitch, the induced air flow becomes uniform along the rotation axis direction, and turbulence occurs. This is because the generation of flow is suppressed and it is advantageous for reducing noise.

  The direction of the helix may be a direction that turns clockwise when moving in a direction away from the motor 501 or a direction that turns counterclockwise, but the air flow induced by the rotation at the time of light emission causes the cylindrical portion 502a to rotate. The direction which flows to the phosphor side at the tip is preferable. That is, in this embodiment, when the rotating body rotates during light emission, as shown as AIR in FIG. 5A, air is configured to flow toward the tip side where the phosphor is provided. It is possible to cool the phosphor efficiently.

  The spiral groove of this embodiment can be easily formed by cutting the outer surface and the inner surface of the cylindrical portion 502a of the rotating body 502 using, for example, a threading tap.

  As described above, the light source of the present embodiment can efficiently cool the phosphor using the rotating body provided with the spiral groove. The generation of turbulent flow is suppressed by keeping the pitch of the spiral provided on the inner surface of the cylindrical portion constant, and for example, noise caused by wind noise can be kept low even when rotating at a high speed of 7200 rpm. In addition, the rotating body according to the present embodiment is easier to manufacture and handle than a rotating body provided with plate-like fins, and the cost can be reduced.

  The light source device provided with the rotating body of the present embodiment can be used for the projection display device described with reference to FIG. 2, similarly to the light source device of the first embodiment. Since the configuration is basically the same, the description thereof is omitted. However, since the light source device of the present embodiment is provided with a phosphor on the cylindrical partial end surface (front surface of the rotating body) of the rotating body, the rotation axis RA of the rotating body is The difference is that the layout is such that it is oriented along the Y axis in FIG. Since the projection type display device of this embodiment can illuminate the light modulation element using a light source device with high output and high quietness, it is possible to display a high brightness image with low noise.

[Fifth embodiment]
A fifth embodiment in which the motor format is different from the first to fourth embodiments will be described.
Various types of motors can be used as the motor for driving the rotating body. In this embodiment, the motor from the front end of the rotating body to the rear end of the motor is used in order to increase the utilization efficiency of the space in the apparatus. An out-rotor type DC brushless motor was used so that the length could be shortened.
FIG. 6A is a cross-sectional view of the rotating body 602 cut along the rotation axis, and FIG. 6B is a front view of the rotating body 602.

  In FIG. 6A, 602 is a rotating body, 603 is a phosphor, 604 is a rotor of an out-rotor type DC brushless motor, 605 is a permanent magnet provided on the rotor, 606 is a laminated core of the stator, and 607 is a stator. It is a coil. The rotating body 602 and the rotor 604 are aligned and fixed so that their rotation axes are concentric, and are integrated.

  A band-shaped phosphor 603 is provided on the front side of the rotating body 602. As shown in FIG. 6B, the band-shaped phosphor 603 includes a region PR to which a red light emitting phosphor is applied, a region PG to which a green light emitting phosphor is applied, and a region to which a yellow light emitting phosphor is applied. Includes PY. On the front side of the rotator 602, a reflection region RB that reflects excitation light is provided along with the band-shaped phosphor, and constitutes a ring as a whole.

As the rotator 602 rotates, the region PR, the region PG, and the region PY are sequentially irradiated with excitation light, and emit red, green, and yellow fluorescence, respectively. Further, when the reflection region RB is irradiated with excitation light (blue laser light), the blue light is reflected by the rotator 602. The base surface of the ring is mirror-finished so that the fluorescence emitted from the regions PR, PG, and PY can be effectively extracted, or the blue laser beam is reflected with high efficiency in the reflection region RB. desirable.
The rotating body 602 is formed of a metal material having high thermal conductivity and reflectance. For example, aluminum or an aluminum alloy is preferably used. The rotating body 602 rotates at a high speed so that the projection display device can display a color image at a high frame rate. Specifically, for example, the rotating body 602 corresponds to a color image display of 120 screens per second at 7200 rpm. Rotate.

  In this embodiment, a groove formed in a spiral shape is provided on the outer surface of the cylindrical portion 602a. It can be said that a groove (concave portion) is formed if the surface farthest from the rotation axis among the outer surfaces of the cylinder is used as a reference, and a spirally extending ridge line (convex portion) is formed if the bottom of the recess is used as a reference. In other words, Alternatively, it may be said that a concavo-convex structure extending in a spiral shape is formed.

  The spiral groove is configured such that the ratio of the rotation angle to the distance traveled in the direction along the rotation axis RA, that is, the pitch is constant, and the spiral winding is at least one round (360 degrees) or more around the outer surface of the cylinder. It extends to rotate. When the rotating body is rotated, the spiral groove induces an air flow. However, as described above, by adopting a spiral with a constant pitch, the induced air flow becomes uniform along the rotation axis direction, and turbulence occurs. This is because the generation of flow is suppressed and it is advantageous for reducing noise.

  The direction of the helix may be a direction that turns clockwise when it moves away from the motor, or a direction that turns counterclockwise, but the direction of the air flow induced by rotation at the time of light emission flows to the phosphor side. preferable. That is, in the present embodiment, when the rotating body rotates during light emission, as shown as AIR in FIG. 6A, the air flows toward the outer surface on the front end side where the phosphor 603 is provided. Therefore, the phosphor 603 can be efficiently cooled.

  The spiral groove according to the present embodiment can be easily formed by cutting the outer surface of the cylindrical portion 602a of the rotating body 602 using, for example, a threading tap.

  As described above, the light source of the present embodiment can efficiently cool the phosphor using the rotating body provided with the spiral groove. The generation of turbulent flow is suppressed by keeping the pitch of the spiral provided on the inner surface of the cylindrical portion constant, and for example, noise caused by wind noise can be kept low even when rotating at a high speed of 7200 rpm. In addition, the rotating body according to the present embodiment is easier to manufacture and handle than a rotating body provided with plate-like fins, and the cost can be reduced.

  Similarly to the light source device of the first embodiment, the light source device including the rotating body of the present embodiment can be used for the projection display device described with reference to FIG. Since the configuration is basically the same, the description thereof will be omitted. However, since the light source device of the present embodiment is provided with a phosphor in front of the rotating body, the rotation axis RA of the rotating body is along the X axis in FIG. The difference is that the layout is oriented. Since the projection type display device of this embodiment can illuminate the light modulation element using a light source device with high output and high quietness, it is possible to display a high brightness image with low noise.

  Moreover, since the out-rotor type DC brushless motor was used, the length from the front end of the rotating body to the rear end of the motor could be shortened, and the utilization efficiency of the space in the apparatus could be increased. In the above embodiment, the rotating body including the phosphor and the spiral groove is joined to the out rotor. However, in some cases, the phosphor and the spiral groove are formed on the outer surface of the rotor of the out-rotor type DC brushless motor. It may be provided.

[Other Embodiments]
In the embodiment described above, the concavo-convex structure extending spirally is provided on one or both of the outer side surface and the inner side surface of the cylindrical portion of the rotating body, but the rotating body of the present invention is not limited to the above example. Various modifications and combinations are possible. For example, the combination of the form of the rotating body and the type of motor (inner rotor type motor, outer rotor type motor, etc.) is not limited to the example of the above-described embodiment.

The portion on which the spiral concavo-convex structure is provided on the rotating body does not have to be a complete cylindrical portion having the same radius along the rotation axis direction. For example, a hollow conical shape whose radius changes along the rotation axis direction is not necessary. It may be an outer surface or an inner surface. Moreover, you may provide in the outer surface of a solid part instead of the side surface of a hollow cylindrical part.
The rotational speed of the rotating body is not limited to 7200 rpm exemplified in the embodiment. For example, when color image display is performed at a display speed of 180 screens / second, it may be rotated at 10800 rpm. Since the rotating body having the spiral structure of the present invention has a feature that the wind noise is small even when rotated at high speed, it can be suitably used for projection display devices of various specifications.

  Moreover, in the said embodiment, although the helical concavo-convex structure same or similar to the thread groove used for a general volt | bolt (male screw) and a nut (female screw) was used, the reason is for generation | occurrence | production prevention of a turbulent flow. This is because it is desirable that the concavo-convex structure has a uniform pitch and the manufacture is easy. As the cross-sectional shape of the concave or convex portion, for example, a shape used for a screw such as a triangular screw, a square screw, a trapezoidal screw, a sawtooth screw, or a round screw can be used. It can be appropriately selected depending on the case. The spiral concavo-convex structure of the present invention is easier to process and handle than a conventional rotating body provided with plate-like fins, and can reduce the manufacturing cost.

  However, since the spiral concavo-convex structure of the present invention is not for fastening members but generates a cooling airflow, the winding direction, the number of threads, the shape of the thread groove, the diameter and the pitch Various modifications can be made to these elements. For example, these elements do not need to be completely constant over the entire area of the spiral concavo-convex structure, and may be partially changed. As long as the air flow can be induced by rotation, it is not necessary to limit to the uneven shape used in a general screw.

  In addition, as described above, the fluorescent surface of the rotating body and the reflecting surface are preferably mirror-finished to improve the light utilization efficiency, but the other surfaces of the rotating body are roughened with minute irregularities. An oxide film (natural color) or a black rough oxide film can be formed, and the heat dissipation efficiency can be further improved by increasing the surface area.

Moreover, the fluorescent substance provided in the rotating body is not limited to the three colors R, B, and Y exemplified in the embodiment, and the type and the number of colors can be changed.
In addition, examples of the position where the phosphor is provided have been shown on the side surface, the slope, and the front surface of the rotating body. However, the present invention is not limited to this. For example, a single rotating body may be used to combine the phosphors into a plurality of parts. May be.

  The projection display device using the light source of the present invention is not limited to the embodiment described with reference to FIG. 2, and various modifications can be made. For example, a light modulation device that modulates illumination light from a light source is not limited to a reflective light modulation device such as a DMD or a reflective liquid crystal device. For example, a three-plate projection display device can be configured using a transmissive light modulation element such as a transmissive liquid crystal panel and a color separation optical system.

101 ... motor / 102 ... rotary body / 102a ... cylindrical part / 102b ... disc-like part / 102c ... annular slope part / 102d ... axial part / 103 ... Phosphor / 200 ... light source device / 210 ... relay lens / 211 ... excitation light source unit / 212 ... excitation light source side condensing lens / 213 ... polarization beam splitter / 214 ... 4 Half-wave plate / 215 ... phosphor side condensing lens / 220 ... color selection wheel / 221 ... motor / 240 ... light tunnel / 250 ... illumination lens / 260 ... light modulation Device / 271 ... Prism / 272 ... Prism / 280 ... Projection lens / 290 ... Projection screen / 301 ... Motor / 302 ... Rotating body / 302a ... Cylindrical part / 30 b ... disk-shaped part / 302c ... axial center part / 303 ... phosphor / 304 ... recessed part / 305 ... recessed part / 401 ... motor / 402 ... rotating body / 402a ... Cylindrical part / 402b ... Disk-like part / 402c ... Axis center part / 403 ... Phosphor / 404 ... Recessed part / 405 ... Recessed part / 402d ... Helical Groove / 402e ... spiral groove / 501 ... motor / 501H ... motor hub / 502 ... rotating body / 502a ... cylindrical part / 502b ... disc-like part / 502c ... Axial part / 503 ... phosphor / 502d ... spiral groove / 502e ... spiral groove / 504 ... screw / 602 ... rotating body / 602a ... cylindrical part /603...phosphor/604...rotor/605...permanent magnet / 06 ... Stacked core of stator / 607 ... Coil of stator / AIR ... Airflow / PR ... Region to which red-emitting phosphor is applied / PG ... Green-emitting phosphor is applied Area / PY ... area to which a yellow-emitting phosphor is applied / RB ... reflection area / RA ... rotation axis

Claims (9)

A light source device for a projection display device,
A rotating body made of metal,
A phosphor coated on the rotating body;
An excitation light source that outputs excitation light for exciting the phosphor;
And having
The rotating body has a concavo-convex structure extending spirally along its side surface.
A light source device characterized by that. The rotating body has a cylindrical portion, and the concavo-convex structure extending in a spiral shape is provided on at least one of an inner side surface and an outer side surface of the cylindrical portion,
The light source device according to claim 1. The concavo-convex structure extending in a spiral shape is formed such that the ratio of the rotation angle to the distance traveling in the direction of the rotation axis of the rotating body is constant.
The light source device according to claim 1, wherein: The spiral of the concavo-convex structure extending in a spiral shape rotates 360 degrees or more.
The light source device according to claim 1, wherein the light source device is a light source device. The rotating direction of the rotating body is a direction in which an air flow induced by the spirally extending uneven structure flows in the direction of the phosphor.
The light source device according to claim 1, wherein the light source device is a light source device. The phosphor is coated on the inclined surface of the rotating body,
The light source device according to claim 1, wherein the light source device is a light source device. The phosphor is coated on the front surface of the rotating body,
The light source device according to claim 1, wherein the light source device is a light source device. The phosphor is coated on a side surface of the rotating body,
The light source device according to claim 1, wherein the light source device is a light source device. The light source device according to any one of claims 1 to 8,
A light modulation element and a projection lens;
A projection type display device characterized by that.

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