WO2019107261A1

WO2019107261A1 - Light source device and projection type display device using same

Info

Publication number: WO2019107261A1
Application number: PCT/JP2018/043105
Authority: WO
Inventors: 雄也蔵田; 紘史山本; 公哉星野; 悟史西川
Original assignee: キヤノン株式会社
Priority date: 2017-11-29
Filing date: 2018-11-22
Publication date: 2019-06-06

Abstract

This light source device 100 is provided with a photosynthetic unit 3 provided with: a red LD array 1 that emits light in a red band; a blue LD array 2 that emits light in a blue band; a transmission region 31T that transmits light from the red LD array 1; and a reflection region 31R that reflects light from the blue LD array 2.

Description

Light source device and projection display device using the same

The present invention relates to a light source device and a projection display device using the same.

As a projector capable of displaying a color image using a blue laser diode (hereinafter blue LD) that emits blue light and a yellow phosphor that converts part of blue light from the blue LD into green light and red light The projector disclosed in Patent Document 1 is known.

Patent Document 1 discloses a light source device that combines blue light from two blue LD arrays by a light combining section having alternately arranged transmission areas and reflection areas, and guides a part of the combined blue light to a yellow phosphor. Discloses a projector using the.

JP, 2016-1868892, A

Yellow phosphors can emit green light and red light, but yellow phosphors tend to lack red light with respect to green light. Therefore, it is difficult to project a reddish image on the screen with sufficient brightness in the projector described in the above-mentioned Patent Document 1 in which the red light used for the projection image is only the red light from the yellow phosphor. It is.

Then, this invention aims at providing the light source device which can implement | achieve the projection of a brighter image than before, and the projection type display apparatus using the same.

In order to achieve the above object, the light source device of the present invention
A first light source unit that emits light in a first wavelength band;
A second light source unit for emitting light of a second wavelength band different from the light of the first wavelength band;
A transmission region for transmitting the light from the first light source unit, and a light combining unit including a reflection region for reflecting the light from the second light source unit, and the light of the first wavelength band and the first light source Of the two wavelength bands, one is the blue band and the other is the red band,
It is characterized by

According to the present invention, it is possible to provide a light source device capable of realizing projection of an image brighter than before and a projection type display device using the same.

Configuration diagram of a projection display apparatus equipped with the light source device of each embodiment Configuration diagram of the light source device of the first embodiment Configuration diagram of the light combining unit included in the light source device of each embodiment Configuration diagram of the light combining unit included in the light source device of each embodiment Configuration diagram of the light combining unit included in the light source device of each embodiment The figure which shows the optical path of the blue light in the light source device of 1st Example The figure which shows the optical path of the red light in the light source device of 1st Example The figure which shows the optical path of the fluorescence light in the light source device of 1st Example Characteristic diagram of polarization separation film in each example The figure which shows the spectral distribution of the light from the light source device in each Example Configuration diagram of light source device according to the second embodiment Configuration diagram of the polarization separation unit of the second embodiment Configuration diagram of the polarization separation unit of the second embodiment Configuration diagram of the polarization separation unit of the second embodiment The figure which shows the optical path of the blue light in the light source device of 2nd Example The figure which shows the optical path of the red light in the light source device of 2nd Example The figure which shows the optical path of the fluorescent light in the light source device of 2nd Example Configuration diagram of the light combining unit of the modified example Configuration diagram of the light combining unit of the modified example

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Configuration of projection display device)
First, the configuration of a projector (projection display device) P on which the light source device described in each embodiment described later can be mounted will be described using FIG. 1.

The projector P includes a light source device 100, a light modulation unit that modulates light from the light source device 100, and a holding unit SU that holds a projection lens (projection optical system) PL that projects an image on a screen (projected surface) SC. ing. The light modulation portion referred to here is a generic name of a light modulation portion LP1 for red light, a light modulation portion LP2 for green light, and a light modulation portion LP3 for blue light which will be described later. In FIG. 1, the light modulation unit is a light modulation unit LP1 for red light, a light modulation unit LP2 for green light, and a light modulation unit LP3 for blue light are constituted by a transmissive liquid crystal panel.

Note that the holding unit SU may hold the projection lens PL in a removable manner, or the projection lens PL may not be removable from the holding unit SU. The holding unit SU may be configured as a shift unit capable of shifting the projection lens PL in the direction orthogonal to the optical axis of the projection lens PL while holding the projection lens PL.

The projector P further includes an illumination optical system IS, a color separation / combination system, and a projection lens PL. The color separation / combination system is composed of dichroic mirrors DM1 and DM2, mirrors M1, M2 and M3, field lenses FL1, FL2 and FL3, and relay lenses RL1 and RL2, which will be described later.

The red light R, the green light G, and the blue light B emitted from the

light source devices

100 and 101 described in the following embodiments are incident on the dichroic mirror DM1 through the illumination optical system IS. The dichroic mirror DM1 transmits red light R and reflects green light G and blue light B. The illumination optical system IS includes a first fly eye lens, a second fly eye lens, a polarization conversion unit for aligning the polarization direction in a specific direction, and the like, and has a function of illuminating the light modulation unit with a uniform illuminance distribution. .

(Light path of red light R)
The red light R transmitted through the dichroic mirror DM1 is incident on the light modulation unit LP1 for red light through the mirror M1 and the field lens FL1. The red light R incident on the red light light modulation unit LP1 is modulated by the red light light modulation unit LP1 based on the image signal, and is incident on the combining prism CP.

(Light path of green light G)
The green light G reflected by the dichroic mirror DM1 is incident on the dichroic mirror DM2. The dichroic mirror DM2 has a characteristic of reflecting green light G and transmitting blue light B. The green light G reflected by the dichroic mirror DM2 is incident on the light modulation unit LP2 for green light through the field lens FL2. The green light G incident on the light modulation unit LP2 for green light is modulated by the light modulation unit LP2 for green light based on the image signal, and is incident on the combining prism CP.

(Optical path of blue light B)
The blue light B transmitted through the dichroic mirror DM1 is also transmitted through the dichroic mirror DM2. The blue light B transmitted through the dichroic mirror DM2 is incident on the light modulation unit LP3 for blue light through the relay lens RL1, the mirror M2, the relay lens RL2, the mirror M3, and the field lens FL3. The blue light B incident on the light modulation unit LP3 for blue light is modulated by the light modulation unit LP3 for blue light based on the image signal, and is incident on the combining prism CP.

The red light R, the green light G, and the blue light B incident on the combining prism CP in the above optical path are guided to the projection lens PL by the combining prism CP and finally reach the screen SC.

First Embodiment
(Configuration of light source device 100)
Next, the configuration of the light source device 100 according to the first embodiment of the present invention will be described with reference to FIG.

As shown in FIG. 2, the light source device 100 includes a red LD array (first light source unit) 1 that emits red light R (light of a first wavelength band) and blue light B (light of a second wavelength band). ) (A second light source unit) 2. The light source device 100 further includes a light combining unit 3 including a transmission area for transmitting the red light R and a reflection area for reflecting the blue light B.

As shown in FIGS. 3A and 3B, in the light synthesis unit 3, an aluminum reflection film 32 (reflection unit) is provided on part of the surface 31A of the transparent substrate 31 on the side where the blue LD array 2 is provided. It is configured. The above-mentioned transmission area is an area 31T of the transparent substrate 31 where the aluminum reflection film 32 is not provided, and the above-mentioned reflection area is an area 31R where the aluminum reflection film 32 is provided. That is, the light combining portion 3 includes the transparent substrate 31 provided with the reflective portion having the reflective region and the transmissive portion having the transmissive region.

Further, as shown in FIG. 3C, an anti-reflection film is provided on the surface 31B of the transparent substrate 31 on which the red LD array 1 is provided. This makes it possible to guide most of the red light R from the red LD array 1 to the light combining unit 3.

The light source device 100 further includes a positive lens 41 and a negative lens 42, and the compression optical system 4 for narrowing the width of light from the light combining unit 3 and rotation around a direction parallel to the traveling direction of light from the light combining unit 3 A possible λ / 2 plate (first retardation plate) 5 is provided. By narrowing the width of the light from the light combining unit 3 with the compression optical system 4, it becomes possible to miniaturize each optical member provided after the compression optical system 4 and to miniaturize the entire light source device 100 as well. It becomes possible. In addition, by rotating the λ / 2 plate 5, the ratio of the light amount of the light from the light combining unit 3 to the phosphor unit 12 described later to the light amount of the light to the diffuser unit 9 is changed. Is possible. As a result, it is possible to adjust the color of the projected image.

The light source device 100 further includes a polarization separating unit 6, a λ / 4 plate (second retardation plate) 7, a condensing optical system 8 including

condensing lenses

81 and 82, a diffuser unit including a diffuser wheel 91 and a motor 92. A (diffusion unit) 9 is provided. The condensing optical system 8 has a function of guiding the light from the λ / 4 plate 7 to the diffuser wheel 91 and converting the light from the diffuser wheel 91 into parallel light and guiding the light to the λ / 4 plate 7. . The diffuser wheel 91 has a configuration in which a diffusion layer for diffusing light from the λ / 4 plate 7 is provided in a ring shape on an aluminum substrate. Since the diffuser wheel 91 is rotated by the motor 92, it is possible to prevent light from continuing to hit a specific part of the diffusion layer and to suppress deterioration of the diffusion layer.

The light source device 100 further includes a λ / 4 plate (third retardation plate) 10, a condensing optical system 11 including condensing

lenses

111 and 112, and a phosphor unit (wavelength conversion unit) including a phosphor wheel 121 and a motor 122. It has twelve. The condensing optical system 12 has a function of guiding the light from the λ / 4 plate 10 to the phosphor wheel 121 and converting the light from the phosphor wheel 121 into parallel light and guiding the light to the λ / 4 plate 10 . The phosphor wheel 121 has a configuration in which a yellow phosphor layer for converting the wavelength of light from the λ / 4 plate 10 is provided in a ring shape on an aluminum substrate. Since the phosphor wheel 121 is rotated by the motor 122, it is possible to prevent light from continuing to hit a specific part of the yellow phosphor layer and to suppress deterioration of the yellow phosphor layer.

(Light path of blue light B _LD )
The optical path along which the blue light B _LD from the blue LD array 2 is guided to the illumination optical system IS via the diffuser unit 9 and the phosphor unit 12 will be described using FIG. As described above, by rotating the λ / 2 plate 5, the ratio of the light amount of the light from the light combining unit 3 guided to the phosphor unit 12 described later to the light amount of the light guided to the diffuser unit 9 is It is possible to change. In other words, by rotating the λ / 2 plate 5, blue light B _LD S of S polarized light (light of the first polarized direction) from the λ / 2 plate 5 and light of the P polarized light (second polarized direction) It is possible to adjust the ratio of blue light B _LD P). The ratio of the blue light _{B LD} P of the blue light _{B LD} S and P-polarized light of S-polarized light in the description of the optical path of the blue light _{B LD} is 1: Assume 1.

The s-polarized blue light B _LD S and the p-polarized blue light B _LD P from the λ / 2 plate 5 are incident on the polarization separation film (polarization separation region) 612 of the polarization separation unit 6. The polarization separation film 612 is provided on the entire surface of the transparent substrate 611 of the polarization separation unit 6. The characteristics of the polarization separation film 612 will be described with reference to FIG. As shown in FIG. 7, the polarization separation film 612 performs polarization separation on the blue light B _LD (wavelength 450 nm) from the blue LD array 2 and the red light R _LD (wavelength 640 nm) from the red LD array 1. The other light is reflected or transmitted (transmitted in this embodiment) regardless of the polarization direction.

In other words, the polarization separation unit 6 (polarization separation film 612) is formed of light of a first predetermined wavelength band including light of a first wavelength band and light of a second predetermined wavelength band including light of a second wavelength band. Polarization separation is performed on light. Then, light of a wavelength band different from the light of the first predetermined wavelength band and the light of the second predetermined wavelength band is transmitted or reflected regardless of the polarization direction. In FIG. 7, the light of the first wavelength band is red light R _LD (wavelength 640 nm) from the red LD array 1, and the light of the second wavelength band is blue light B _LD (wavelength 450 nm) from the blue LD array 2. ). The light of the first predetermined wavelength band and the light of the second predetermined wavelength band mean light of a range in which the reflectance is 50%. In FIG. 7, the light of about 440 to 470 nm is the light of the second predetermined wavelength band, and the light of about 630 to 653 nm is the light of the first predetermined wavelength band.

Therefore, of the S-polarized blue light B _LD S and P-polarized blue light B _LD P from the λ / 2 plate 5, the S-polarized blue light B _LD S is reflected by the polarization separation film 612 and λ / 4. The light is guided to the plate 10, and the blue light B _LD P of P-polarization passes through the polarization separation film 612 and is guided to the λ / 4 plate 7.

The S-polarized blue light B _LD reflected by the polarization separation film 612 is incident on the yellow phosphor layer on the phosphor wheel 121 via the λ / 4 plate 10 and the focusing optical system 11. The yellow phosphor layer has a characteristic of wavelength-converting at least a part of blue light as excitation light into yellow light (red light and green light) as fluorescent light having a longer wavelength than blue light.

The unconverted blue light not converted by the yellow phosphor layer among the blue light B _{LD of} S polarization enters the polarization separation film 612 through the condensing optical system 11 and the λ / 4 plate 10. The unconverted blue light incident on the polarization separation film 612 has a disordered polarization direction, and the component of S-polarization among the unconverted blue light is reflected by the polarization separation film 612 and returns to the blue LD array 2. The component of P-polarization passes through the polarization separation film 612 and is guided to the illumination optical system IS.

On the other hand, P-polarized blue light B _LD P transmitted through the polarization separation film 612 is guided to the diffuser wheel 91 via the λ / 4 plate 7 and the focusing optical system 8. The blue light diffused by the diffuser wheel 91 is incident on the polarization separation film 612 through the condensing optical system 8 and the λ / 4 plate 7. In other words, the lambda / 4 plate 7 until the blue light towards the diffuser unit 9 direction from the polarization separating film 612 is incident on the polarization separating film 612 again to pass twice, the blue light B _{LD S} next to S-polarized light, polarized light The light is reflected by the separation film 612 and guided to the illumination optical system IS.

(Light path of red light R _LD )
The optical path along which the red light R _LD from the red LD array 1 is guided to the illumination optical system IS via the diffuser unit 9 and the phosphor unit 12 will be described using FIG. Like the description of the optical path of the above-described blue light B _LD, the ratio of the red light R red light S-polarized light in the description of the optical path of the _LD R _{LD S} and P-polarized light of the red light R _{LD P} is 1: 1 Suppose.

The S-polarized red light R _LD S reflected by the polarization separation film 612 is incident on the yellow phosphor layer on the phosphor wheel 121 through the λ / 4 plate 10 and the focusing optical system 11. Unlike in the case of the blue light B _LD described above, the red light incident on the yellow phosphor layer is not wavelength-converted, and the polarization direction is not disturbed either, through the condensing optical system 11 and the λ / 4 plate 10 again. The light is incident on the polarization separation film 612.

That is, red light from the polarization separation film 612 in the direction of the phosphor unit 12 passes through the λ / 4 plate 10 twice before entering the polarization separation film 612 again, so red light from the λ / 4 plate 10 is P It becomes polarization. Therefore, the P-polarized red light R _LD P from the λ / 4 plate 10 is transmitted through the polarization separation film 612 and guided to the illumination optical system IS. On the other hand, P-polarized red light R _LD P traveling through the λ / 2 plate 5 and the polarization separation film 612 to the λ / 4 plate 7, the condensing optical system 8 and the diffuser unit 9 is the above-mentioned polarization separation film The same light path is taken as in the case of P-polarized blue light B _LD P transmitted through the P.612. Finally, the light becomes an S-polarized red light R _LD S and is guided to the illumination optical system IS.

(Optical path of fluorescent light)
The optical path in which the fluorescent lights R _F and G _F from the phosphor unit 12 are guided to the illumination optical system IS will be described with reference to FIG. As described above, fluorescent light (green light G _F and red light R _F ) is emitted from the yellow phosphor layer on the phosphor wheel 121. Since the polarization separation film 612 has the above-mentioned characteristics, the fluorescence light R _F and G _F which are incident on the polarization separation film 612 have blue and blue light LDs from the blue _LD and red light R _LD from the red light _LD. The different components are transmitted through the polarization separation film 612 and guided to the illumination optical system IS. In addition, if the fluorescent light R _F and G _F incident on the polarization separation film 612 contain the same components as the red light R _LD P of P polarization and the blue light B _LD P of P polarization, that component is also polarization separation The light passes through the film 612 and is guided to the illumination optical system IS.

As described above, the light source device 100 can guide red light, green light, and blue light to the illumination optical system IS.

(The reason why projection of brighter images than before can be realized)
Next, the reason why the light source device 100 shown in this embodiment can reproduce a wider color range than the conventional one will be described using FIG. FIG. 8 is a view showing a spectral distribution of light emitted from the light source device 100. As shown in FIG.

As shown in FIG. 8, the light source device 100 can emit red light from the red LD in addition to blue light and fluorescent light from the blue LD which can be emitted from the conventional light source device. That is, in the projector P on which the light source device 100 is mounted, red light from the red LD can be used as red light to be used for the projection image, in addition to red light contained in fluorescent light from the yellow phosphor layer . As a result, the light source device 100 can realize projection of an image brighter than in the past.

Although it is conceivable to increase the number of blue LDs to increase the amount of blue light incident on the yellow phosphor layer in order to increase the amount of red light contained in the fluorescent light, the amount of blue light that can be converted by the phosphor can be increased. Because there is a limit, there is a limit to increasing the red light contained in the fluorescent light. On the other hand, in the light source device 100 shown in this embodiment, the red light is increased by using the red LD array instead of increasing the red light contained in the fluorescent light. It is possible to realize projection of an image brighter than before without depending on

Further, since red light is insufficient in the conventional projector as described above, it is necessary to reduce green light and blue light in accordance with a small amount of red light when projecting an entire surface white image. More specifically, when the light modulation unit is a reflection type, it is necessary to reduce the reflectance of the light modulation unit for both colors of light for green light and blue light to reduce the green light and blue light guided to the screen was there.

As a result, although the brightness of the entire white image is reduced in the conventional projector, such a decrease in brightness can be suppressed in the light source device 100 shown in the present embodiment.

Further, in the light source device 100 shown in the present embodiment, for example, the red LD array 1 emits red light of a wavelength other than 640 nm in addition to the red LD (first red light source) which emits red light of 640 nm. (The second red light source) may also be provided. This makes it possible to reproduce a wider color gamut than ever before.

Further, in the light source device 100 shown in the present embodiment, since light from two light source portions is combined by one light combining portion as in the conventional case, while the light source device is prevented from being enlarged, It is possible to realize the above-mentioned effect of the brightness improvement.

(More preferred form)
Next, a configuration for strengthening the above effect or a configuration for obtaining an effect other than the above effect will be described.

As shown in FIG. 1, in the light source device 100, red light from the red LD array 1 is transmitted through the light combining unit 3, and blue light from the blue LD array 2 is reflected by the light combining unit 3. In general, when the light amount loss in the case of reflecting light by an aluminum reflection film or the like is compared with the light amount loss in the case of light being transmitted through glass, the light amount loss in the case of transmitting is smaller. For this reason, as in the light source device 100, the red LD array 1 and the light combining unit 3 are configured such that the red light from the red LD array 1 passes through the light combining unit 3 as described above. It is possible to compensate for more red light.

Further, as shown in FIG. 1, the number of red LDs included in the red LD array 1 is larger than the number of blue LDs included in the blue LD array 2 so that the above-mentioned influence due to the lack of red light is caused. Can be further suppressed. That is, the red LD array 1 (first light source unit) includes a plurality of red LDs (first light sources), and the blue LD array 2 (second light source unit) includes a plurality of blue LDs (second light sources). Including. And it is preferable that the red LD array 1 which inject | emits the light of a red zone among red LD array 1 and blue LD array 2 has more light sources.

Further, as shown in FIG. 3A, the area of the transmission region 31T is larger than the area of the reflection region 31R. Alternatively, the width W1 of the transmission area 31T is larger than the width W2 of the reflection area 31R. According to such a configuration, even if the position of the red LD array 1 is deviated from the desired position due to a mounting error or the like, the light from the red LD array 1 is prevented from being blocked by the reflecting portion 32. Is possible.

Second Embodiment
(Configuration of light source device 101)
Next, the configuration of a light source device 101 as a second embodiment of the present invention will be described using FIG. The difference between the light source device 100 shown in the first embodiment described above and the light source device 101 shown in the present embodiment is the difference in the configuration of the polarization separation unit and that the λ / 4 plate 10 (FIG. 2) is not provided. It is.

(Configuration of polarization separation unit 61)
The configuration of the polarization separation unit 61 will be described with reference to FIG. As shown in FIGS. 10A, 10B, and 10C, the polarization separation unit 61 includes a transparent substrate 611, a polarization separation film 612 provided on the incident side surface of the transparent substrate 611, and a phase difference application unit (phase difference application region) 613. And a polarization separation film 612 provided on the surface on the emission side. The polarization separation film 612 performs polarization separation of blue light from the blue LD array 2 and red light from the red LD array 1 as described with reference to FIG. 7 in the first embodiment described above. The light has the property of being transmitted regardless of the polarization direction.

While the polarization separation film 612 is provided on the entire surface of the transparent substrate 611 on the incident side in the polarization separation unit 6 described in the first embodiment, the surface on the incident side in the polarization separation unit 61 The polarization separation film 612 is provided in part of the The phase difference providing unit 613 is provided in a region different from the region where the polarization separation film 612 is provided, more specifically, around the polarization separation film 612. The phase difference providing unit 613 has a characteristic of converting incident S-polarized light into P-polarized light and converting P-polarized light into S-polarized light.

The polarization separation film 612 on the incident side of the polarization separation unit 61 is provided at such a position that most of the light from the compression optical system 4 is incident on the polarization separation film 612 on the incident side of the polarization separation unit 61. There is. In addition, when the incident side surface of the polarization separation unit 61 is viewed from the direction of the optical axis of the compression optical system 4, the area from which the light from the compression optical system 4 is applied to the incident side surface of the polarization separation unit 61 Also, the area of the polarization separation film 612 is wider. The

polarization separation section

6 and 61 are the same in that the polarization separation film 612 is provided on the entire surface on the output side.

(Light path of blue light B _LD )
The optical path along which the blue light B _LD from the blue LD array 2 is guided to the illumination optical system IS via the diffuser unit 9 and the phosphor unit 12 will be described using FIG. The description of portions similar to those of the first embodiment described above will be omitted.

Of the S-polarized blue light B _LD S and P-polarized blue light B _LD P from the λ / 2 plate 5, the S-polarized blue light B _LD S is a polarization splitting film 612 on the incident side of the polarization splitter 61. And is directed toward the phosphor unit 12.

Among the blue light incident on the polarization separation film 612 provided on the incident side surface of the polarization separation unit 61 with the unconverted blue light from the yellow phosphor layer, the P polarization component is polarized and separated on the incident side and the emission side. The light passes through the film 612 and is guided to the illumination optical system IS. Further, of the blue light incident on the phase difference providing unit 613 with the unconverted blue light from the yellow phosphor layer, the P-polarized light component is guided to the illumination optical system IS through the polarization separation film 612 on the output side. .

Of the S-polarized blue light B _LD S and P-polarized blue light B _LD P from the λ / 2 plate 5, the P-polarized blue light B _LD P is transmitted through the polarization separation film 612 on the incident side and the emission side. In the direction of the diffuser unit 9. Then, finally, it becomes blue light B _LD S of S polarization and is guided to the illumination optical system IS.

(Light path of red light R _LD )
The optical path along which the red light R _LD from the red LD array 1 is guided to the illumination optical system IS via the diffuser unit 9 and the phosphor unit 12 will be described using FIG. The description of portions similar to those of the first embodiment described above will be omitted.

Of the S-polarized red light R _LD S and P-polarized red light R _LD P from the λ / 2 plate 5, the S-polarized red light R _LD S is a polarization separation film 612 on the incident side of the polarization separation unit 61. And is directed toward the phosphor unit 12.

Of the S-polarized red light R _LD S from the yellow phosphor layer, the component incident on the polarization separation film 612 on the incident side returns to the λ / 2 plate 5 side. Of the S-polarized red light R _LD S from the yellow phosphor layer, the component incident on the phase difference providing unit 613 becomes P-polarized red light R _LD P by the phase difference providing unit 613, and the polarization separation film 612 on the output side It passes through and is led to the illumination optical system IS. On the other hand, the P-polarized red light R _LD P transmitted through the incident side polarization separation film 612 follows the same optical path as the P polarized blue light B _LD P transmitted through the incident side polarization separation film 612 described above. , Are directed in the direction of the diffuser unit 9. Finally, the light becomes an S-polarized red light R _LD S and is guided to the illumination optical system IS.

(Optical path of fluorescent light)
The optical path in which the fluorescent lights R _F and G _F from the phosphor unit 12 are guided to the illumination optical system IS will be described with reference to FIG. Components of fluorescent light R _F and G _F incident on the incident side polarization separation film 612 that are different in wavelength from the blue light B _LD from the blue _LD and the red light R _LD from the red light _LD are polarized on the incident side and the emission side The light passes through the separation film 612 and is guided to the illumination optical system IS. Fluorescent light R _F incident on the phase difference providing unit _613, components red light R _LD and wavelength is different from the blue light B _LD and red light LD from the blue LD of the G _F is transmitted through the polarization separating film 612 on the exit side Then, it is guided to the illumination optical system 612.

In addition, if fluorescent light R _F and G _F incident on the polarization separation film 612 on the incident side contain the same components as red light R _LD P of P polarization and blue light B _LD P of P polarization, the components The light is also transmitted through the polarization separation film 612 on the incident side and the emission side and is led to the illumination optical system IS. The same components as the red light R _LD P of P polarization and the blue light B _LD P of P polarization are added to the fluorescent light R _F and G _F incident to the polarization separation film 612 on the output side via the phase difference imparting unit 613. If it is included, that component is also transmitted through the polarization separation film 612 on the output side and guided to the illumination optical system IS.

As described above, the light source device 101 can guide red light, green light, and blue light to the illumination optical system IS.

(Effect obtained by the present embodiment)
In the present embodiment, the λ / 4 plate 10 provided in the light source device 100 shown in the first embodiment described above may not be used. Therefore, it is possible to realize a lighter or lower cost light source device having a smaller number of parts as compared with the first embodiment described above. Also in the present embodiment, as in the above-described first embodiment, it is possible to realize projection of an image brighter than in the prior art.

(Modification)
As mentioned above, although the preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

For example, although the configuration of the light source device 100 including the λ / 4 plate 10 is illustrated in the first embodiment described above, the present invention is not limited to such a configuration, and the λ / 4 plate 10 is not included. It may be a configuration.

In each of the above-described embodiments, the red light from the red LD array 1 is transmitted through the light combining unit 3 and the blue light from the blue LD array 2 is reflected by the light combining unit 3. It is not limited to such a configuration. The red light from the red light LD array 1 may be reflected by the light combining unit 3 and the blue light from the blue LD array 2 may be transmitted through the light combining unit 3 contrary to the above-described embodiments. That is, one of the light of the first wavelength band from the first light source unit and the light of the second wavelength band from the second light source unit is light of the blue band, and the other is light of the red band. I hope there is.

The light in the blue band or the blue light is light in which the wavelength of the light with the maximum intensity in the spectral distribution of the light or the full width at half maximum is included in the band of 430 to 480 nm. Further, the light in the green band or the green light refers to the light of the maximum intensity in the spectral distribution of the light or the light in which the full width at half maximum is 500 to 580 nm. Further, the light in the red band or the red light refers to light in which the wavelength of the light of maximum intensity or the full width at half maximum of the spectral distribution of the light is included in the band of 600 to 750 nm.

In the first embodiment described above, the polarization separation film 612 is provided on the surface of the transparent substrate 611 on the λ / 2 plate 5 side and the λ / 4 plate 7 side, but at least one of them is The polarization separation film 612 may be provided on the surface of

In each of the above-described embodiments, the light combining unit 3 includes the aluminum reflection film as the reflection unit. However, the present invention is not limited to such a configuration. For example, instead of the aluminum reflection film as the reflection unit, a dichroic film (color separation unit) may be used which reflects blue light from the blue LD array 2 and transmits red light from the red LD array 1.

Further, the configuration of the light combining unit 3 may be the configuration shown in FIG. More specifically, as shown in FIG. 14A, the reflectors are arranged in an array, or as shown in FIG. 14B, the strip-like reflection mirror 321 is used as a reflector, and a plurality of reflection mirrors 321 are interposed between The configuration may be such that the space is a transmission region. The configuration shown in FIG. 14B can be rephrased as a configuration in which a plurality of mirrors constitute a reflection area and a space between a plurality of mirrors constitutes a transmission area.

Further, a dichroic film (color separation portion) may be provided on the surface 31B of the transparent substrate 31 instead of or in addition to the antireflective film, for transmitting red light and reflecting blue light.

Further, in each of the embodiments described above, the red LD array 1 has only the red LD as a light source, and the blue LD array 2 has only the blue LD as a light source. However, the present invention is not limited to such a configuration. For example, the red LD array 1 may have a blue LD in addition to the red LD, and the blue LD array 2 may have a red LD in addition to the blue LD. That is, the light combining unit may be provided with a transmission region for transmitting the light from the first light source unit and a reflection region for reflecting the light from the second light source unit.

Further, the polarization direction of the light from the red LD array 1 and the polarization direction of the light from the blue LD array 2 may be different from each other. For example, when the polarization direction of the light from the red LD array 1 is a P polarization direction, the polarization direction of the light from the blue LD array 2 may be S.

Further, the means for combining the light from the first light source unit and the light from the second light source unit is not limited to the light combining unit 3 described above. For example, instead of the light combining unit 3, a dichroic mirror may be used which transmits the light from the first light source unit and reflects the light from the second light source unit. Even when a dichroic mirror is used instead of the light combining unit 3, the same effect as that of the first embodiment described above can be obtained by providing the λ / 4 plate 10 as in the first embodiment described above. Also in the case of using a dichroic mirror instead of the light combining unit 3, the same effect as that of the above-mentioned second embodiment can be obtained by providing the polarization separation unit 61 as in the above-mentioned second embodiment.

The present invention is not limited to the above embodiment, and various changes and modifications can be made without departing from the spirit and scope of the present invention. Accordingly, the following claims are attached to disclose the scope of the present invention.

The present application claims priority based on Japanese Patent Application No. 2017-229552 filed on Nov. 29, 2017 and Japanese Patent Application No. 2018-205875 submitted on October 31, 2018, The entire contents of the description are incorporated herein.

Claims

A first light source unit that emits light in a first wavelength band;
A second light source unit for emitting light of a second wavelength band different from the light of the first wavelength band;
A transmission region for transmitting the light from the first light source unit, and a light combining unit including a reflection region for reflecting the light from the second light source unit, and the light of the first wavelength band and the first light source Of the two wavelength bands, one is the blue band and the other is the red band,
A light source device characterized by
The light of the first wavelength band is the light of the red band, and the light of the second wavelength band is the light of the blue band,
The light source device according to claim 1,
The light combining portion includes a transparent substrate provided with a reflective portion having the reflective region and a transmissive portion having the transmissive region.
The light source device according to claim 1 or 2, characterized in that:
The reflection unit provided on the transparent substrate is a color separation unit that transmits light in the first wavelength band and reflects light in the second wavelength band.
The light source device according to claim 3,
The light combining unit has a first surface on the side on which the first light source unit is provided, and a second surface on the side on which the second light source unit is provided, and the first surface is the first surface Is equipped with an anti-reflective coating,
The light source device according to any one of claims 1 to 4, characterized in that:
The light combining unit has a first surface on the side on which the first light source unit is provided, and a second surface on the side on which the second light source unit is provided, and the first surface is the first surface Is provided with a color separation unit that transmits the light of the first wavelength band and reflects the light of the second wavelength band,
The light source device according to any one of claims 1 to 5, characterized in that:
The light combining unit is configured such that an area of the transmission area is larger than an area of the reflection area.
The light source device according to any one of claims 1 to 6, characterized in that:
The light combining unit forms the reflection area by a plurality of mirrors, and forms the transmission area by a space between the plurality of mirrors.
The light source device according to any one of claims 1 to 7, characterized in that:
A wavelength converter,
A diffusion unit,
A first retardation plate on which light from the light combining section is incident;
Among the light from the first retardation plate, the light of the first polarization direction is guided to the wavelength conversion unit, and the light of the second polarization direction is different from the light of the first polarization direction. A polarization separation unit leading to the diffusion unit;
And a second retardation plate provided between the polarization separation unit and the diffusion unit.
The light source device according to any one of claims 1 to 8, characterized in that.
The first retardation plate is a λ / 2 plate, and is rotatable with a direction parallel to the traveling direction of the light from the light combining unit as a rotation axis,
The second retardation plate is a λ / 4 plate,
The light source device according to claim 9, characterized in that:
A third retardation plate provided between the polarization separation unit and the wavelength conversion unit;
The light source device according to claim 9 or 10,
The third retardation plate is a λ / 4 plate,
The light source device according to claim 11, characterized in that:
The polarization separation unit polarizes light in a first predetermined wavelength band including light in the first wavelength band and light in a second predetermined wavelength band including light in the second wavelength band. The light is separated, and light of a wavelength band different from the light of the first predetermined wavelength band and the light of the second predetermined wavelength band is transmitted or reflected regardless of the polarization direction.
The light source device according to any one of claims 9 to 12, characterized in that:
The first light source unit includes a plurality of first light sources, and the second light source unit includes a plurality of second light sources,
Among the plurality of first light sources and the plurality of second light sources, the one emitting the light in the red band has more light sources,
The light source device according to any one of claims 1 to 13, characterized in that:
The first light source unit includes: a first red light source emitting a first red light; and a second red light source emitting a second red light having a wavelength different from that of the first red light. Have,
The light source device according to any one of claims 2 to 14, characterized in that.
The polarization direction of the light of the first wavelength band and the polarization direction of the light of the second wavelength band are different from each other
The light source device according to any one of claims 1 to 15, characterized in that.
Of the light from the first retardation plate, light of a first polarization direction is guided to the wavelength conversion section on the surface on the light combining section side of the polarization separation section, and the light of the first polarization direction is An area for guiding light of a second polarization direction different from the light in the polarization direction to the diffusion section, and a phase difference application area are provided.
The light source device according to any one of claims 13 to 16, characterized in that:
A first light source unit that emits light in a first wavelength band;
A second light source unit for emitting light of a second wavelength band different from the light of the first wavelength band;
A dichroic mirror that transmits light from the first light source unit and reflects light from the second light source unit;
A wavelength converter,
A diffusion unit,
A first retardation plate on which light from the dichroic mirror is incident;
Among the light from the first retardation plate, the light of the first polarization direction is guided to the wavelength conversion unit, and the light of the second polarization direction is different from the light of the first polarization direction. A polarization separation unit leading to the diffusion unit;
A second retardation plate provided between the polarization separation unit and the diffusion unit;
A third retardation plate provided between the polarization separation unit and the wavelength conversion unit;
One of the light of the first wavelength band and the light of the second wavelength band is light of the blue band, and the other is light of the red band.
A light source device characterized by
A first light source unit that emits light in a first wavelength band;
A second light source unit for emitting light of a second wavelength band different from the light of the first wavelength band;
A dichroic mirror that transmits light from the first light source unit and reflects light from the second light source unit;
A wavelength converter,
A diffusion unit,
A first retardation plate on which light from the dichroic mirror is incident;
Among the light from the first retardation plate, the light of the first polarization direction is guided to the wavelength conversion unit, and the light of the second polarization direction is different from the light of the first polarization direction. A polarization separation unit leading to the diffusion unit;
A second retardation plate provided between the polarization separation unit and the diffusion unit;
One of the light of the first wavelength band and the light of the second wavelength band is light of the blue band, and the other is light of the red band,
Of the light from the first retardation plate, light of a first polarization direction is guided to the wavelength conversion section on the surface on the light combining section side of the polarization separation section, and the light of the first polarization direction is An area for guiding light of a second polarization direction different from the light in the polarization direction to the diffusion section, and a phase difference application area are provided.
A light source device characterized by
The light source device according to any one of claims 1 to 19,
A light modulation unit that modulates light from the light source device;
And a holding unit for holding a projection optical system that projects the light modulated by the light modulation unit onto a projection surface.
A projection display apparatus characterized by