JP2015022249A - Optical path branching optical system, illumination light source device utilizing optical path branching optical system, image display device utilizing illumination light source device and projection device utilizing image display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical path branching optical system that is downsized and compact, and easily manufacturable.SOLUTION: An optical path branching optical system 2 comprises: an optical path branch member 5 that has a transmission part causing excitation light to be transmitted when positioned in an emission optical path P1 of excitation light BP, and generates a transmission optical path P2 ahead a transmission direction, and a reflection part causing the excitation light to be reflected when positioned in the emission optical path P1, and generates a reflection optical path P3 ahead a reflection direction; and an optical path deflection member 6 that is disposed in the reflection optical path P3 and deflects the excitation light guided to the reflection optical path P3 toward the optical path branch member 5. In the optical path branch member 5, an optical path P4 is formed that generates red light RP, by the excitation light guided to the transmission optical path P2 when the transmission optical path P2 is formed, and the transmission part and the reflection part are divided into a segment area so that an optical path P5 that generates blue light and an optica path P6 that generates green light, by the excitation light guided to the reflection optical path P3 when the reflection optical path P3 is formed, are formed in time division due to a relation between the transmission and the reflection.

Description

  The present invention relates to an optical path branching optical system, an illumination light source device using the optical path branching optical system, an image display device using the illumination light source device, and an improvement of a projection device using the image display device.

  2. Description of the Related Art Conventionally, a projection apparatus is known in which two rotating mirror wheels that are divided into a transmission part and a reflection part are provided in series in an emission optical path of a laser diode that generates blue laser light as an excitation light source. (For example, refer to Patent Document 1).

  In this projection device, the two rotating mirror wheels are rotated synchronously, and the optical path for generating blue light, the optical path for generating green light, and the red light are reflected by the reflection / transmission relationship of the two rotating mirrors. The optical path for generating light is divided in terms of time.

  Moreover, the thing of the structure provided with the white light source, the color wheel as an optical path branching member, and the visible light reflection mirror as an optical path deflection member is known for a projection apparatus (for example, refer patent document 2).

  The color wheel includes a filter region that reflects red light and transmits green light and blue light every 60 degrees, and reflects blue light and transmits green light and red light around the rotation center axis. And a filter region that reflects green light and transmits red light and blue light.

  In this case, one light component of the three primary color light components constituting the white light from the white light source is reflected by the filter region that reflects the light component of one color (for example, blue). The remaining two color components (for example, red and green) are transmitted through the filter region, guided to the visible light reflecting mirror, and reflected by the visible light reflecting mirror toward the color wheel.

  The remaining two-color (red and green) light components are different from the filter region that reflects the one-color (blue) light component (eg, the red light component is reflected and the blue light component and green light component are reflected). It is separated by the relationship between reflection and transmission by a filter region that transmits light components). Thereby, white light is decomposed into three primary colors of blue light, green light, and green light.

  In the technique disclosed in Patent Document 1, a laser diode that generates blue laser light is used as an excitation light source in order to form an optical path that generates blue light, an optical path that generates green light, and an optical path that generates red light. Therefore, it is not necessary to provide a phosphor as a wavelength conversion member for generating blue light in the optical path for generating blue light, and the illumination light source device can be reduced in size and size.

  However, the technique disclosed in Patent Document 1 requires a rotational drive source for rotating the two rotating mirror wheels in synchronization with each other, so that the optical path branching optical system is enlarged. Further, the structure of the control device for synchronously rotating the rotary mirror is also complicated. For this reason, there is an inconvenience that it is difficult to reduce the size and size.

  On the other hand, in the technique disclosed in Patent Document 2, an optical path for generating blue light, an optical path for generating green light, and an optical path for generating red light are formed by a color filter as an optical path branching member and an optical path deflecting member. Therefore, it is not necessary to provide a separate rotation drive source, and the optical path branching optical system can be made compact. However, since a white light source is used as the illumination light source device, there is a disadvantage that the illumination light source device is enlarged.

  Further, a color wheel as an optical path branching member has a filter region that reflects red light and transmits green light and blue light every 60 degrees, and a filter that reflects blue light and transmits green light and red light. Since it is necessary to form a region and a filter region that reflects green light and transmits red light and blue light, there is a problem that the manufacturing of the optical path branching member is complicated.

  The present invention relates to an optical path branching optical system that is small, compact, and easy to manufacture, an illumination light source device using the optical path branching optical system, an image display device using the illumination light source device, and a projection device using the image display device. The purpose is to provide.

An optical path branching optical system according to the present invention is positioned in the emission optical path and a transmission unit that transmits the excitation light and generates a transmission optical path forward in the transmission direction when positioned in the emission optical path of the excitation light from the excitation light source. An optical path branching member having a reflection part that reflects the excitation light and generates a reflected optical path forward in the reflection direction,
In the case where the reflection light path is disposed in one of the reflection light path and the transmission light path and is disposed in the reflection light path, the excitation light guided to the reflection light path is deflected toward the light path branching member, and In the case where it is disposed in the transmission optical path, an optical path deflecting member that deflects the excitation light guided to the transmission optical path toward the optical path branching member is provided.

  When the optical path deflecting member is disposed in the reflected optical path, the optical path branching member is generated by the excitation light guided to the transmitted optical path when the transmitted optical path is generated. And an optical path for generating green light and an optical path for generating red light are formed, and the remaining two light beams are generated by excitation light guided to the reflected light path when the reflected light path is generated. When the optical path deflecting member is disposed in the transmitted optical path so that two optical paths are formed in a time-sharing manner according to the relationship between transmission and reflection, the reflected optical path is generated when the reflected optical path is generated. The guided excitation light forms one optical path of an optical path that generates the blue light, an optical path that generates the green light, and an optical path that generates the red light, and the transmitted optical path is generated. Sometimes the excitation light led to the transmitted light path Ri as two optical paths of the residual is formed by time division by the relationship between reflection and transmission, and the transmission portion and the reflection portion is a region divided into segments area.

  According to the present invention, when the optical path deflecting member is disposed in the reflected optical path, the optical path branching member generates blue light by the excitation light guided to the transmitted optical path when the transmitted optical path is generated. One of the optical path for generating the green light, the optical path for generating the green light, and the optical path for generating the red light is formed, and the remaining two light beams are generated by the excitation light guided to the reflected light path when the reflected light path is generated. Since the transmission part and the reflection part are divided into segment areas so that one optical path is formed by time division according to the relationship between transmission and reflection, the optical path branching member is easy to manufacture and the optical path branching The optical system can be reduced in size and size. The same effect can be obtained when the optical path deflecting member is disposed in the transmitted optical path.

FIG. 1a is an optical diagram of the illumination light source device according to the first embodiment of the present invention, where the segment region 1T of the optical path branching member shown in FIG. It is explanatory drawing which shows the state in which the optical path which produces | generates red light was formed by doing. FIG. 1B is a plan view of the optical path branching member shown in FIG. 1A, and shows an irradiation state of excitation light to the segment region 1T when the segment region 1T is positioned in the emission optical path and an optical path for generating red light is formed. It is explanatory drawing. FIG. 2A is an optical diagram of the illumination light source device according to the first embodiment of the present invention, where the segment area 2T of the optical path branching member shown in FIG. It is explanatory drawing which shows the state in which the optical path which produces | generates red light was formed by doing. FIG. 2B is an explanatory diagram illustrating an irradiation state of excitation light to the segment region 2T when the segment region 2T of the optical path branching member illustrated in FIG. 2A is positioned in the emission optical path and an optical path for generating red light is formed. FIG. 3A is an optical diagram of the illumination light source device according to the first embodiment of the present invention, in which the segment region 3R of the optical path branching member shown in FIG. And is an explanatory view showing a state in which an optical path for generating blue light is formed by the segment region 6R existing at a 180-degree symmetrical position with respect to the rotation center axis of the optical path branching member. FIG. 3B is an explanatory diagram showing an irradiation state of excitation light to the segment region 3R shown in FIG. 3A and an irradiation state of excitation light to the segment region 6R shown in FIG. 3A. FIG. 4A is an optical diagram of the illumination light source device according to the first embodiment of the present invention, in which the segment region 4R is located in the exit light path of the excitation light from the excitation light source to form a reflected light path, and the optical path branching member It is explanatory drawing which shows the state in which the optical path which produces | generates green light by the segment area | region 1T which exists in a 180 degree symmetrical position on the boundary of a rotation center axis was formed. FIG. 4B is an explanatory diagram showing an irradiation state of the excitation light to the segment region 4R shown in FIG. 4A and an irradiation state of the excitation light to the segment region 1T shown in FIG. 4A. FIG. 5a is an optical diagram of the illumination light source device according to the first embodiment of the present invention, in which the segment region 5R is located in the exit light path of the excitation light from the excitation light source to form a reflected light path, and the optical path branching member It is explanatory drawing which shows the state in which the optical path which produces | generates green light by the segment area | region 2T which exists in a 180 degree symmetrical position on the boundary of a rotation center axis was formed. FIG. 5B is an explanatory diagram showing an irradiation state of the excitation light to the segment region 5R shown in FIG. 5A and an irradiation state of the excitation light to the segment region 2T. FIG. 6A is an optical diagram of the illumination light source device according to the first embodiment of the present invention, in which the segment region 6R is located in the exit light path of the excitation light from the excitation light source to form a reflected light path, and the optical path branching member It is explanatory drawing which shows the state in which the optical path which produces | generates blue light by the segment area | region 3R which exists in a 180 degree symmetrical position on the boundary of a central axis was formed. FIG. 6B is an explanatory diagram showing the irradiation state of the excitation light on the segment region 6R and the irradiation state on the segment region 3R. 6C is an explanatory diagram showing a general relationship between the fan-shaped angle of the segment region of the transmission part T of the optical path branching member shown in FIGS. 1B to 6B and the fan-shaped angle of the segment area of the reflection part R. FIG. 6d is an optical diagram of an illumination light source device according to a modification of the first embodiment of the present invention, in which a fluorescent member that generates red light is disposed in the optical path P5 shown in FIGS. 1a to 6a, and green light is disposed in the optical path P6. It is explanatory drawing which shows the structure which has arrange | positioned the fluorescent member which generate | occur | produces, and made the transmitted optical path P4 the optical path which produces | generates blue light. FIG. 7 is an explanatory diagram schematically showing the overall configuration of the projection apparatus according to Embodiment 2 of the present invention. FIG. 8 is a time sequence diagram illustrating an example of the relationship between the duration time of blue light, red light, and green light generated in one frame and the segment region of the optical path branching member. FIG. 9 is a time sequence diagram illustrating another example of the relationship between the duration time of blue light, red light, and green light generated in one frame and the segment region of the optical path branching member. FIG. 10 is a time sequence diagram illustrating still another example of the relationship between the duration time of blue light, red light, and green light generated in one frame and the segment region of the optical path branching member. FIG. 11 is a time sequence diagram showing still another example of the relationship between the duration time of blue light, red light, and green light generated in one frame and the segment region of the optical path branching member. FIG. 12 is an optical diagram of the illumination light source apparatus according to the third embodiment of the present invention. FIG. 13 is an optical diagram of an illumination light source apparatus according to Example 4 of the present invention. FIG. 14 is an explanatory diagram illustrating an example of the configuration of the fluorescent member illustrated in FIG. 13.

Example 1
FIG. 1A to FIG. 6A are optical diagrams showing an illumination light source device having an optical path branching optical system according to Embodiment 1 of the present invention.
1A to 6A, reference numeral 1 denotes an illumination light source device, and reference numeral 2 denotes an optical path branching optical system. The illumination light source device 1 includes an excitation light source 3, a collimating lens as a condensing element 4, and an optical path branching optical system 2.

  In the first embodiment, the excitation light source 3 is a blue laser diode that generates blue laser light BP as excitation light. The condensing element 4 is provided in the emission optical path P1 of the blue laser light BP, and plays a role of condensing the blue laser light BP.

  The optical path branching optical system 2 includes an optical path branching member 5 and an optical path deflecting member 6. The optical path branching member 5 has a rotation drive source (for example, a drive motor) shown in FIGS. 1A to 6A around the rotation center axis O1 shown in FIGS. ) It is composed of a rotating disk that is rotationally driven by 7 '. Here, the optical path branching member 5 is disposed at an angle of 45 degrees with respect to the emission optical path P1, but the present invention is not limited to this.

  The optical path branching member 5 transmits the blue laser light BP when it is positioned in the emission optical path P1 of the blue laser light BP from the excitation light source 3, and generates a transmission optical path P2 forward in the transmission direction. A reflection unit R that reflects the blue laser beam BP when it is positioned in the optical path P1 and generates a reflected optical path P3 in the front of the reflection direction; The transmission part T can be formed by, for example, a dichroic mirror that transmits the blue laser light BP, and the reflection part R can be formed by a dichroic mirror that reflects the blue laser light BP.

  In FIG. 1A to FIG. 6A, the optical path deflecting member 6 is provided in parallel with the optical path branching member 5 in the reflected optical path P3. The optical path deflecting member 6 plays a role of deflecting the blue laser light BP guided to the reflected optical path P3 toward the optical path branching member 5 again.

  In the first embodiment, the optical path deflecting member 6 is provided in parallel to the optical path branching member 5, but the function of deflecting the blue laser light BP guided to the reflected optical path P3 toward the optical path branching member 5 is provided. Need not be parallel.

  In the first embodiment, the optical path deflecting member 6 has a single configuration, but may have a dual configuration. Further, in the first embodiment, the optical path deflecting member 6 is provided in the reflected optical path P3, but may be provided in the transmitted optical path P2.

In the optical path branching member 5, when only the transmission optical path P2 is substantially generated, the optical path P4 that generates the red light RP is generated by the blue laser light BP guided to the transmission optical path P2, and only the reflection optical path P3 is substantially generated. Due to the blue laser light BP guided to the reflected light path P3, the two light paths of the light path P5 for generating the blue light BP ′ and the light path P6 for generating the green light GP are caused by the relationship between transmission and reflection. The transmission part T and the reflection part R are virtually divided into segment areas so as to be formed by time division.
In this embodiment, the transmissive part T and the reflective part R have been described as being virtually divided into segment areas. However, the present invention is not limited to this, and each segment area is formed by physically dividing the area. You can also

  That is, the transmissive portion T and the reflective portion R are divided into sector-shaped segment regions around the rotation center axis O1 as shown in FIGS. 1B to 6B. Here, the fan-shaped angle of the transmission part T is 120 degrees, and the fan-shaped angle of the reflection part R is 240 degrees.

  The transmission part T is virtually divided into two fan-shaped segment areas 1T and 2T having the same shape. The reflection portion R is virtually divided into four fan-shaped segment regions 3R, 4R, 5R, and 6R having the same shape.

  That is, the optical path branching member 5 is virtually divided into six segment segments having a fan angle of 60 degrees, and virtual segment areas 1T, 2T, 3R to 6R that are symmetrical about the rotation center axis O1 every 60 degrees. Have

  A dichroic mirror 7 and a fluorescent member 8 as a wavelength conversion member are provided in the optical path P4. The fluorescent member 8 includes a fluorescent material 8a that is excited by the blue laser light BP and generates red light RP, and a reflective substrate 8b.

  The dichroic mirror 7 has a function of transmitting the blue laser light BP and reflecting the red light RP, and also functions as an optical path combining member that forms a combined optical path in cooperation with a dichroic mirror described later.

  The optical path P6 is provided with a dichroic mirror 9 and a fluorescent member 10 as a wavelength conversion member. The fluorescent member 10 includes a fluorescent material 10a that is excited by blue laser light BP and generates green light GP, and a reflective substrate 10b.

  The dichroic mirror 9 has a function of transmitting the blue laser beam BP and the red light RP and reflecting the green fluorescence GP, and also functions as an optical path combining member that forms a combined optical path in cooperation with the dichroic mirror 7. Have.

The optical path P5 is provided with a dichroic mirror 11 that reflects the blue laser light BP, transmits the red light RP and the green light GP, and cooperates with the dichroic mirrors 7 and 9 to form a combined optical path. Yes.
Below, the effect | action of this illumination light source device 1 is demonstrated.

(Operation of Example 1)
Here, the optical path branching member 5 has a state in which the segment region 1T of the transmission part T is positioned in the emission optical path P1, and the clockwise direction from this state with respect to the traveling direction of the blue laser light BP (in the direction of the arrow X1) ) Is assumed to rotate at a constant speed.

  As shown in FIG. 1A, when the segment region 1T of the transmissive part T is located in the emission optical path P1, only the transmitted optical path P2 is generated. The blue laser beam BP is guided to the dichroic mirror 7 via the transmission optical path P2, and is transmitted through the dichroic mirror 7 to be irradiated on the fluorescent member 8. As a result, the fluorescent material 8a is excited by the blue laser light BP, and red light RP is generated.

The red light RP is reflected by the dichroic mirror 7 and guided to the dichroic mirror 9. The red light RP passes through the dichroic mirror 9 and is guided to the dichroic mirror 11. After passing through the dichroic mirror 11, the red light RP is guided to a projection optical system described later. As shown in FIG. 2A, when the segment region 2T of the transmission part T is positioned on the emission optical path P1, only the transmission optical path P4 is generated in the same manner, so that only the red light RP is generated.
When only the transmitted light path P2 is generated, the segment laser diodes 4R and 5R are not irradiated with the blue laser light BP, as shown in FIGS. 1B and 2B.

  Next, as shown in FIG. 3, when the segment region 3R of the reflection portion R is positioned on the emission optical path P1, only the reflection optical path P3 is generated. Thereby, the blue laser beam BP is reflected toward the optical path deflecting member 6. The blue laser beam BP is reflected again toward the optical path branching member 5 by the optical path deflecting member 6 and guided to the segment region 6R of the reflecting portion R. That is, the segment region 6R is irradiated with the blue laser beam BP.

  The segment region 6R forms an optical path P5 that generates blue light BP '. The blue laser beam BP is guided again to the optical path deflecting member 6 through the optical path P5 formed by the segment region 6R.

  The blue laser beam BP is reflected again by the optical path deflecting member 6, guided to the dichroic mirror 11, reflected by the dichroic mirror 11, and guided to the projection optical system described later as blue light BP '.

  Next, as shown in FIG. 4A, when the segment region 4R of the reflection portion R is positioned on the emission optical path P1, only the reflection optical path P3 is generated. Similarly, the blue laser beam BP is reflected toward the optical path deflecting member 6, and is deflected again toward the optical path branching member 5 by the optical path deflecting member 6.

  When the segment region 4R of the reflection portion R is located in the emission optical path P1, the segment region 1T of the transmission portion T is located in front of the blue laser light BP reflected by the optical path deflecting member 6 in the reflection direction. That is, the segment region 1T is located in the reflected light path P3, and the segment region 1T is irradiated with the blue laser light BP.

  Since the blue laser beam BP passes through the segment region 1T, an optical path P6 for generating the green light GP is formed by the segment region 1T. The blue laser beam BP passes through the segment region 1T and is guided to the dichroic mirror 9.

  The blue laser beam BP passes through the dichroic mirror 9 and is irradiated on the fluorescent member 10. Thereby, the fluorescent material 10a is excited by the blue laser light BP, and the green light GP is generated. The green light GP is guided by the dichroic mirror 11 after being reflected by the dichroic mirror 9. The green light GP passes through the dichroic mirror 11 and is guided to a projection optical system described later.

  As shown in FIG. 5A, when the segment region 5R of the reflecting portion R is located, only the reflected light path P3 is formed in the same manner, and the segment region 2T is located in the reflected light path P3. Green light GP is generated.

  Next, as shown in FIG. 6A, when the segment region 6R of the reflection portion R is positioned in the emission optical path P1, only the reflection optical path P3 is generated. The blue laser beam BP is reflected toward the optical path deflecting member 6 and guided to the segment region 3R of the reflecting portion R of the optical path branching member 5 by the optical path deflecting member 6.

  The segment region 3R forms an optical path P5 that generates blue light BP '. The blue laser beam BP is guided again toward the optical path deflecting member 6 through the optical path P5 formed by the segment region 3R.

  The blue laser beam BP is reflected by the optical path deflecting member 6, guided to the dichroic mirror 11, reflected by the dichroic mirror 11, and guided to the projection optical system described later as the blue light BP '.

Thus, during one rotation of the optical path branching member 5, the blue light BP ′, the green light GP, and the red light RP are periodically generated.
That is, assuming that the optical path branching member 5 rotates at a constant speed, the optical path P5 that generates the blue light BP ′, the optical path P6 that generates the green light GP, and the red light RP are generated during one rotation of the optical path branching member 5. The optical path P4 can be formed for the same time.

  According to the illumination light source device 1, the color of light guided from the dichroic mirror 11 to the projection optical system is red, red, blue, green, green during one rotation of the optical path branching member 5, that is, during one cycle. Are switched in the order of blue, and the red duration, the green duration, and the blue duration are the same in one cycle.

In the first embodiment, the optical path branching member 5 is divided into six in the rotation direction to form virtual segment regions every 60 degrees. However, the present invention is not limited to this.
(Modification 1)
For example, as shown in FIG. 6c, the angle of the transmission portion T (the sum of the angle θ1 of the segment region 1T and the angle θ1 of the segment region 2T) 2θ1 and the rotation center axis with respect to the segment regions 1T and 2T The angle 2θ1 ′, which is the sum of the angle θ1 ′ of the segment region 4R and the angle θ1 ′ of the segment region 5R, which is present at a 180-degree symmetrical position with respect to O1, is the same (2θ1 ′ = 2θ1) When the angle θ2 of the segment region 3R of the portion R and the angle θ2 ′ of the segment region 6R are set to the same angle θ2 = θ2 ′, it may be set so as to satisfy the relationship of 2θ1 + θ2 = 180 degrees.

  For example, if 2θ1 = 90 degrees and θ2 = 90 degrees, when one frame of an image is made to correspond to the rotation angle 360 degrees of the optical path branching member 5, the time for generating red and green is the rotation of the optical path branching member 5. The time for which blue is generated is 90 degrees in terms of angle, and 180 degrees in terms of the rotation angle of the optical path branching member 5.

For example, if 2θ1 = 130 degrees and θ2 = 50 degrees, when one frame of the image is made to correspond to the rotation angle 360 degrees of the optical path branching member 5, the duration of generation of red and green is the optical path branching member 5. In terms of the rotation angle of the optical path branching member 5, the rotation time of the blue light is 130 degrees and the rotation time of the optical path branching member 5 is 100 degrees.
The white balance is adjusted by adjusting the durations during which the optical path P4, the optical path P5, and the optical path P6 are generated in one cycle according to the intensity of red, green, and blue light.

(Modification 2)
In the first embodiment, a fluorescent material 8a that generates red light RP is disposed in front of the traveling direction of the blue laser light BP that travels through the transmission optical path P2, travels through the reflection optical path P3, is reflected by the deflecting member 6, and is a segment region. A fluorescent material 10a that generates green light GP is disposed in front of the blue laser light BP that travels through 1T and 2T in the traveling direction.

  However, as shown in FIG. 6d, the fluorescent member 8 that generates the red light RP may be disposed in the optical path P5, and the blue light BP ′ may be generated by the blue laser light BP that travels through the transmission optical path P2.

  In this case, a total reflection mirror 7 ″ is disposed in the transmission optical path P2 instead of the dichroic mirror 7. Also, instead of the dichroic mirror 9, the dichroic mirror 9 that transmits the blue light BP ′ and reflects the green light GP. Further, instead of the dichroic mirror 11, a dichroic mirror 11 'that reflects the red light RP and transmits the green light GP and the blue light BP' is used.

  According to this modification, when θ1 = 130 degrees and θ2 = 100 degrees, the duration of the blue light BP ′ and the duration of the green light GP are equivalent to 130 degrees as the rotation angle of the optical path branching member 5. The duration of the red light RP is a time corresponding to 100 degrees as the rotation angle of the optical path branching member 5.

  In addition, the fluorescent member 10 that generates the green light GP can be disposed in the optical path P5. In this case, the duration of the blue light GP ′ and the duration of the red light RP are equivalent to 130 degrees as the rotation angle of the optical path branching member 5, and the duration of the green light GP is the rotation of the optical path branching member 5. An angle corresponds to 100 degrees.

  The optical characteristics of the dichroic mirrors 9 ′ and 11 ′ may be any characteristics as long as the red light RP, the blue light BP ′, and the green light GP are guided to the projection optical system. The detailed explanation is omitted.

(Example 2)
FIG. 8 is a block diagram illustrating an overall configuration of a projection apparatus including the light source device 1 according to the first embodiment of the invention.
In FIG. 8, reference numeral 20 denotes a projection device. The projection device 20 includes the illumination light source device 1 according to the first embodiment, an image input interface unit 21, a control device 22, a light source driving device 23, and a projection optical system 24.

  In Example 2, the illumination light source device 1 is provided with a condensing element 8 ′ between the dichroic mirror 7 and the fluorescent member 8, and the condensing element 10 is provided between the dichroic mirror 9 and the fluorescent member 10. 'Is provided so that the irradiation intensity of the blue laser light BP to the fluorescent members 8 and 10 can be increased.

  The projection optical system 24 includes a condensing element 24A, a light tunnel 24B, illumination lenses 25 and 26, a reflection mirror 27, a concave mirror 28, and a digital micromirror device (DMD) as an image forming unit (image forming panel) for forming a color image. ) 29 and the projection lens 30. The illumination light source device 1, the digital micromirror device 29, and the illumination light source device 1, the digital micromirror device 29, and the control device 22 are configured based on the image information.

Image information is input to the image input interface unit 21 from an external device (not shown).
The control device 22 performs drive control of the light source drive device 23 and the digital micromirror device 29 based on image information, and also controls the overall circuit of the projection device.

  The light source driving device 23 controls the excitation light source 3 to emit and extinguish while being controlled by the control device 22 based on the image information. The digital micromirror device 29 has a micromirror in pixel units. Details of the relationship between the period of one frame of image information, the light emission state of the excitation light source 3, the segment area during one rotation of the optical path branching member, and the generated light of each color will be described later.

  The blue light BP ′ reflected by the dichroic mirror 11, the green light GP transmitted through the dichroic mirror 11, and the red light RP are guided to the light tunnel 24B by the condensing element 24A.

The light tunnel 24B has a function of removing unevenness in light intensity. The light of each color is multiple-reflected in the light tunnel while traveling through the light tunnel 24B, and the light has a uniform intensity distribution and is emitted from the light tunnel 24B.
The light of each color is guided to the illumination lenses 25 and 26, collected by the illumination lenses 25 and 26, and then guided to the reflection mirror 27.

The light of each color is reflected by the reflecting mirror 27, guided to the concave mirror 28, and reflected by the concave mirror 28 toward the digital micromirror device 29.
In the digital micromirror device 29, the angle of the micromirror is controlled at two positions. The control device 22 controls the repetition time interval of the two-position control of the angle of the micromirror based on the image information. Thereby, gradation control is performed.

  The light of each color reflected by the digital micromirror device 29 is enlarged by the projection lens 30 and projected onto the screen S1. Thereby, an image is projected on the screen S1.

(Relationship between the period of one frame of image information, the light emission state of the excitation light source, the segment area during one rotation of the optical path branching member, and the generated light of each color)
FIG. 8 is a time sequence diagram illustrating an example of the relationship between the duration (duration) of blue light, red light, and green light generated in one frame and the segment region of the optical path branching member.
When the image information is input, the control device 22 turns on the excitation light source 3 by the light source driving device 23 to emit light (see FIG. 8B).

(Specific example 1)
Here, if the start time of an arbitrary nth frame and the start time of the (n + 1) th frame of the image information shown in FIG. 8A correspond to the start time (0 °) of the segment area 1T, FIG. As shown in (c), the segment areas 1T and 2T correspond to the duration (corresponding to 120 degrees) of the red light RP.

The segment area 3R corresponds to the duration of the blue light BP ′ (corresponding to 60 degrees), the segment areas 4R and 5R correspond to the duration of the green light GP (corresponding to 120 °), and the segment area 6R corresponds to the blue light BP. It corresponds to the duration of '(equivalent to 60 °).
The excitation light source 3 is continuously turned on, and the power intensity of light of each color or the irradiation time of the blue light BP ′, the green light GP, and the red light RP is adjusted so as to become white within a period of one frame.

(Specific example 2)
In this specific example 2, the transmissive part T is 90 degrees, the reflective part R is 270 degrees, the fan-shaped angle of the transmissive part T is 45 degrees, and two virtual segment areas 1T and 2T are formed. The reflection part R is divided into virtual segment areas 3R and 6R having a sector angle of 90 degrees and virtual segment areas 4R and 5R having a sector angle of 45 degrees (FIG. 6C). reference).

  In this specific example 2, as shown in FIG. 9C, the segment areas 1T and 2T correspond to the duration of the red light RP (corresponding to 90 °), and the segment area 3R has the duration of the blue light BP ′. (Corresponding to 90 °), the segment regions 4R and 5R correspond to the duration (90 °) of green light (GP), and the segment region 6R is as shown in FIGS. 9 (b) and 9 (c). Furthermore, it corresponds to the extinguishing time of the excitation light source 3.

  According to the second specific example, since the red light RP, the blue light BP ′, and the green light GP are generated once each within one frame period, the blue light BP ′ is generated one time as in the first specific example. Image generation control can be simplified compared to control that occurs twice within a frame period.

  As a result, the followability of the image generation control can be improved for complex images, and the image quality can be improved. Furthermore, since the excitation light source 3 is turned off during one frame period, the temperature rise of the light source device 1 due to the heat generated by the excitation light source 3 can be suppressed, and as a result, the light emission efficiency can be prevented from decreasing due to the temperature increase of the excitation light source 3.

(Specific example 3)
In this specific example 3, as shown in FIG. 10, the duration of the red light RP (equivalent to 90 °), the duration of the blue light BP ′ (equivalent to 90 °), and the duration of the green light GP (equivalent to 90 °). ) And the duration (equivalent to 90 °) of the blue light BP ′, and when the blue light BP ′ is generated twice during one frame period, in order to ensure white balance, the blue light BP ′ The power of the excitation light source 3 is set to half the power of the excitation light source 3 during the duration of other colors (red light RP, green light GP).

(Modification of Example 2)
FIG. 11 shows an illumination light source device 1 that is generated as one frame period of image information, a light emission state of an excitation light source, and a segment region during one rotation of an optical path branching member of a projection device equipped with the configuration shown in FIG. It is explanatory drawing which shows the relationship with the light of each color.

In this modification, the duration of blue light BP ′ (equivalent to 90 °), the duration of green light GP (equivalent to 90 °), the duration of red light RP (equivalent to 90 °), and the duration of green light GP When the green light GP is generated twice during the period of one frame, the power of the excitation light source 3 is changed to the other power during the duration of the green light BP ′ in order to ensure white balance. The power is one half of the power of the excitation light source 3 during the duration of the color (red light RP, blue light GP).
In addition, in accordance with the time distribution of the time that the blue light generated corresponding to the segment area in one frame lasts, the time that the red light lasts, and the time that the green light lasts, white in one frame In this way, the power of the excitation light source 3 can be controlled to adjust the white balance.

  In the second embodiment, the image information is input from the outside via the image input interface unit 21. However, the image information may be generated inside the projection apparatus.

Example 3
FIG. 12 is an optical diagram of the illumination light source device 1 according to Embodiment 3 of the present invention.
In Example 3, a laser diode that generates laser light VP in the ultraviolet wavelength region is used as the excitation light source 3.

  The optical path P2 includes a dichroic mirror 30 that transmits the laser light VP and reflects the red light RP, and a fluorescent member 8 that is excited by the laser light VP and generates the red light RP.

  The optical path P6 is provided with a dichroic mirror 31 that transmits the laser light VP and the red light RP and reflects the green light GP, and a fluorescent member 10 that is excited by the laser light VP and generates the green light GP. .

In the optical path P5, a dichroic mirror 32 that transmits the laser light VP, the red light RP, and the green light GP and reflects the blue light BP ′, and a fluorescent member 33 that is excited by the laser light VP to generate the blue light BP, Is provided. Like the fluorescent members 8 and 10, the fluorescent member 33 includes a fluorescent material 33a and a reflective substrate 33b.
Since the operation of the illumination light source device 1 is the same as that of the first embodiment, detailed description thereof is omitted.

Example 4
FIG. 13 is an optical diagram of the illumination light source device 1 according to Embodiment 4 of the present invention.
In the fourth embodiment, optical path synthesis is achieved using a cross prism 34 instead of using the dichroic mirrors 30 to 32 shown in FIG.

As the excitation light source 3, a laser diode that generates laser light VP in the ultraviolet wavelength region is used as in FIG. A fluorescent member 8 that generates red light RP is disposed in the optical path P2.
A fluorescent member 10 that generates green light GP is disposed in the optical path P6. A fluorescent member 33 that generates blue light BP ′ is disposed in the optical path P5.

  As shown in an enlarged view in FIG. 14, each fluorescent member 8, 10, 33 has a pair of transparent substrates 34, 35, and a fluorescent material 36 is provided between the pair of transparent substrates 34, 35. . A dichroic mirror film 34 a that transmits the laser beam VP and reflects the fluorescence is formed on the inner surface side in close contact with the fluorescent material 36 on the transparent substrate 34 on the side where the laser beam VP is incident.

  The transparent substrate 35 opposite to the side on which the laser beam VP is incident has a dichroic mirror film 35a that reflects the laser beam VP and transmits the fluorescence on the outer surface opposite to the surface close to the fluorescent material 36. Is formed.

  Thereby, the laser beam VP is prevented from being guided to the image forming unit, and the fluorescence is efficiently guided to the image forming unit. In the optical path P6, a cross prism 37 as an optical path combining member is disposed in front of the traveling direction of the green light GP. In the optical path P4, a reflection mirror 38 that reflects the red light RP toward the cross prism 37 is provided in front of the traveling direction of the red light RP.

  In the optical path P5, a reflection mirror 39 that reflects the blue light BP 'toward the cross prism 37 is provided in front of the traveling direction of the blue light BP'. The cross prism 37 reflects the red light RP and transmits the green light GP and the blue light BP ′, and the dichroic mirror surface 37a that reflects the blue light BP ′ and the green light GP and the red light RP. And a surface 37b.

  Blue light, green light, and red light are optically combined by the cross prism and guided to the projection optical system. Thereby, the illumination light source device 1 can be further reduced in size and size, and fluorescence can be efficiently guided to the image forming unit. Further, since the size and size can be reduced, the illumination efficiency can be improved.

  In addition, as shown with a broken line, it can also be set as the structure which provides the liquid crystal panels 37R, 37G, and 37B as an image formation part facing each entrance plane of the cross prism 37. FIG.

DESCRIPTION OF SYMBOLS 1 ... Illumination light source device 2 ... Optical path branching optical system 3 ... Excitation light source 5 ... Optical path branching member 6 ... Optical path deflecting member P1 ... Emission optical path P2 ... Transmission optical path P3 ... Reflection optical path P4-P6 ... Optical path R ... Reflection part T ... Transmission part

JP2013-76968A (FIG. 21) JP 2001-228935 A (paragraphs “0020” and “0021”, FIGS. 4 and 5)

Claims (10)

Transmitting the excitation light when positioned in the emission light path of the excitation light from the excitation light source and generating the transmission optical path forward in the transmission direction and reflecting the excitation light when positioned in the emission light path An optical path branching member having a reflection part that generates a reflected optical path forward in the reflection direction;
In the case where the reflection light path is disposed in one of the reflection light path and the transmission light path and is disposed in the reflection light path, the excitation light guided to the reflection light path is deflected toward the light path branching member, and An optical path deflecting member that deflects the excitation light guided to the transmitted optical path toward the optical path branching member when disposed in the transmitted optical path;
When the optical path deflecting member is disposed in the reflected optical path, the optical path branching member includes an optical path that generates blue light by excitation light guided to the transmitted optical path when the transmitted optical path is generated. One of the optical path for generating green light and the optical path for generating red light is generated, and the remaining two light beams are generated by the excitation light guided to the reflected optical path when the reflected optical path is generated. When the optical path deflecting member is disposed in the transmitted optical path so that the optical path is formed by the relationship between transmission and reflection, the excitation light guided to the reflected optical path when the reflected optical path is generated The optical path for generating the blue light, the optical path for generating the green light, and the optical path for generating the red light are generated, and the transmitted optical path is generated when the transmitted optical path is generated. The remaining two by the excitation light guided to The optical path branching optical system is characterized in that the transmissive part and the reflective part are divided into segment regions so that the optical path of the transmissive part is divided in terms of time according to the relationship between transmission and reflection. .   2. The optical path branching optical system according to claim 1, wherein the optical path branching member is composed of a rotating disk.   The illumination light source device which has the said excitation light source, the condensing element which condenses the said excitation light inject | emitted from the said excitation light source, and the optical path branching optical system of Claim 1 or Claim 2.   The excitation light source is a laser diode that generates laser light in an ultraviolet wavelength region, a blue light generation wavelength conversion member that generates blue light by the laser light is disposed in an optical path that generates the blue light, and the green light is A wavelength conversion member for green light generation that generates green light by the laser light is provided in the optical path to be generated, and a wavelength conversion member for red light generation that generates red light by the laser light is provided in the optical path to generate the red light. The illumination light source device according to claim 3, wherein the illumination light source device is provided.   The excitation light source is a laser diode that generates blue laser light, a wavelength conversion member that generates green light by the blue laser light is provided in an optical path that generates the green light, and the blue light is generated in the optical path that generates the red light. The illumination light source device according to claim 3, wherein a wavelength conversion member that generates red light by laser light is provided.   The optical path combining member for forming a combined optical path by superimposing the optical path for generating the blue light, the optical path for generating the green light, and the optical path for generating the red light with each other. 5. The illumination light source device according to 5.   The illumination light source device according to claim 6, an image forming unit that forms a color image by irradiation with the red light, the blue light, and the green light, the illumination light source device based on image information, and the An image display device comprising: a control device that drives and controls the image forming unit.   The segment region of the transmissive part and the segment region of the reflective part are divided and formed so that the time that the blue light lasts, the time that the red light lasts, and the time that the green light lasts are the same. In addition, a segment region for turning off the excitation light source is formed separately, and the control device turns off the excitation light source when a segment region for turning off the excitation light source is located in the emission optical path. 8. The image display device according to claim 7, wherein   Corresponding to the time distribution of the duration of the blue light generated corresponding to the segment area in one frame, the duration of the red light, and the duration of the green light, it becomes white in one frame. The image display apparatus according to claim 7, wherein the power of the excitation light source is controlled as described above.   10. A projection comprising the image display device according to claim 7, and a projection optical system that irradiates the screen with blue light, green light, and red light guided to the image forming unit. apparatus.