JP2017116674A - Illumination device and projector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illumination device capable of easily separating colors in illumination light, and a projector.SOLUTION: An illumination device includes: a light source device having a first light-emitting unit having a first light-emitting part that emits first light of a first color and a second light-emitting part that emits second light of a second color different from the first color; and a collimation optical system having a first collimator lens to which the first light and second light made incident. The first light and the second light are emitted in directions different from each other from the first collimator lens.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a lighting device and a projector.

  A projector using two dichroic mirrors is known as a color separation optical system that separates white light emitted from a light source device into red light, green light, and blue light (see, for example, Patent Document 1 below).

  As a light emitting device that emits white light, one using a red semiconductor laser element, a green semiconductor laser element, and a blue semiconductor laser element is known (for example, see Patent Document 2 below).

JP 2003-149734 A JP 2010-278098 A

  By the way, even when the light emitting device is used as a light source device for a projector, two dichroic mirrors are required as a color separation optical system, which causes a problem that the configuration becomes complicated.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an illumination device and a projector that can easily perform color separation of illumination light.

  According to the first aspect of the present invention, the first light emitting unit that emits the first light of the first color and the second light of the second color different from the first color are emitted. And a collimating optical system having a first collimator lens on which the first light and the second light are incident. The illumination device is provided in which the first light and the second light are emitted from the first collimator lens in different directions.

  According to the illumination device according to the first aspect, since the collimator lens is used as a color separation optical system, a color separation optical system using a dichroic mirror becomes unnecessary. Therefore, color separation of illumination light can be performed with a simple configuration.

In the first aspect, the light source device includes a third light emitting unit that emits third light of the first color, and a fourth light emitting unit that emits fourth light of the second color. The collimating optical system further includes a second collimator lens on which the third light and the fourth light are incident, and the first light and The third light is emitted from the collimating optical system in a first direction, and the second light and the fourth light are emitted from the collimating optical system in a second direction. Preferably, the first light emitting unit, the second light emitting unit, the first collimator lens, and the second collimator lens are configured.
According to this configuration, it is possible to separate the colors of the light emitted from the first light emitting unit and the second light emitting unit.

In the first aspect, the positional relationship between the first light emitting unit and the second light emitting unit in the first light emitting unit is such that the third light emitting unit and the fourth light emitting unit in the second light emitting unit The positional relationship with the light emitting part is preferably the same.
According to this configuration, it is possible to separate the colors of the light emitted from the first light emitting unit and the second light emitting unit.

In the first aspect, the relative relationship between the first light emitting unit and the first collimator lens is the same as the relative relationship between the second light emitting unit and the second collimator lens. preferable.
According to this configuration, the first light and the third light having the same color travel in the same direction, and the second light and the fourth light having the same color travel in the same direction. Can do.

In the first aspect, the first light uniformizing element on which the light of the first color emitted from the collimating optical system is incident, and the light of the second color emitted from the collimating optical system is incident. It is preferable to further include a second light uniformizing element.
According to this configuration, the illuminance distribution of light of each color can be made uniform.

In the first aspect, it is preferable that each of the first light uniformizing element and the second light uniformizing element is constituted by a diffraction element.
According to this configuration, the illuminance distribution of the light of each color can be easily made uniform by using the diffraction element.

  According to the second aspect of the present invention, the illumination device according to the first aspect, a light modulation device that forms image light by modulating light from the illumination device according to image information, and the image light A projection optical system for projecting is provided.

  Since the projector according to the second aspect includes the illumination device according to the first aspect, the apparatus configuration can be reduced in size.

1 is a diagram illustrating a schematic configuration of a projector according to an embodiment. The figure which showed the principal part structure of the illuminating device. The figure which showed the emission direction of the light by a collimator lens.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent.

First, an example of a projector according to the present embodiment will be described.
FIG. 1 is a diagram illustrating a schematic configuration of a projector according to the present embodiment.
As shown in FIG. 1, the projector 1 of this embodiment is a projection type image display device that displays a color video on a screen SCR. The projector 1 includes an illumination device 2, a light homogenizing optical system 3R, a light homogenizing optical system 3G, a light homogenizing optical system 3B, a light modulating device 4R, a light modulating device 4G, a light modulating device 4B, and a combining optical system. 5 and a projection optical system 6.

FIG. 2 is a diagram illustrating a main configuration of the illumination device 2.
As shown in FIG. 2, the illumination device 2 includes a light source device 2 </ b> A and a collimator lens array 22.
The light source device 2 </ b> A has a plurality of light emitting units 20. The collimator lens array 22 includes a plurality of collimator lenses 22 a arranged in an array corresponding to the arrangement of the plurality of light emitting units 20.

  Each light emitting unit 20 includes a semiconductor laser 20R, a semiconductor laser 20G, and a semiconductor laser 20B. In the present embodiment, the semiconductor laser 20R, the semiconductor laser 20G, and the semiconductor laser 20B are packaged.

  The semiconductor laser 20R emits red red light LR having a peak wavelength in a wavelength range of 600 to 650 nm, for example.

  The semiconductor laser 20G emits green green light LG having a peak wavelength in a wavelength range of 500 to 560 nm, for example.

  The semiconductor laser 20B emits blue blue light LB having a peak wavelength in a wavelength range of 440 to 480 nm, for example.

  In the present embodiment, one light emitting unit 20 emits white light including red light LR, green light LG, and blue light LB toward the corresponding collimator lens 22a.

  Hereinafter, any one of the plurality of light emitting units 20 in FIGS. 1 and 2 is referred to as a light emitting unit 120, and another light emitting unit 20 is referred to as a light emitting unit 220. The collimator lens 22a corresponding to the light emitting unit 120 is referred to as a collimator lens 122a, and the collimator lens 22a corresponding to the light emitting unit 220 is referred to as a collimator lens 222a.

  The light emitting unit 120 corresponds to the “first light emitting unit” in the claims, the light emitting unit 220 corresponds to the “second light emitting unit” in the claims, and the collimator lens 122a corresponds to the claims. The collimator lens 222a corresponds to the “first collimator lens” and the “second collimator lens” in the claims.

  In the present embodiment, the positional relationship between the semiconductor lasers 20R, 20G, and 20B in the light emitting unit 120 is the same as the positional relationship between the semiconductor lasers 20R, 20G, and 20B in the light emitting unit 220.

  That is, in each of the light emitting unit 120 and the light emitting unit 220, the semiconductor laser 20R, the semiconductor laser 20G, and the semiconductor laser 20B are regularly arranged. In the present embodiment, when viewed in plan from the optical axis direction of the collimator lens 22a, the semiconductor laser 20R, the semiconductor laser 20G, and the semiconductor laser 20B are arranged in order from the left side to the right side in FIG.

  In the present embodiment, the relative relationship between the light emitting unit 120 and the collimator lens 122a is the same as the relative relationship between the light emitting unit 220 and the collimator lens 222a.

  That is, in the light emitting unit 120, the light exit of the semiconductor laser 20G is disposed at the focal position of the collimator lens 122a. In the light emitting unit 220, the light exit of the semiconductor laser 20G is disposed at the focal position of the collimator lens 222a. In the light emitting unit 120, the light emission port of the semiconductor laser 20R and the light emission port of the semiconductor laser 20B are arranged on the focal plane of the collimator lens 122a. In the light emitting unit 220, the light exit of the semiconductor laser 20R and the light exit of the semiconductor laser 20B are disposed on the focal plane of the collimator lens 222a. Here, the focal plane of the collimator lens 122a is a plane that is orthogonal to the optical axis of the collimator lens 122a and that includes the focal point of the lens. The focal plane of the collimator lens 222a is a plane orthogonal to the optical axis of the collimator lens 222a and includes the focal point of the lens.

FIG. 3 is a diagram showing the light emission direction of the collimator lenses 122a and 222a.
As shown in FIG. 3, since the semiconductor laser 20G of the light emitting unit 120 is disposed at the focal position M1 of the collimator lens 122a, the green light LG emitted from the semiconductor laser 20G is collimated by the collimator lens 122a. Are emitted in a direction parallel to the optical axis ax1.
In the present embodiment, the semiconductor laser 20G of the light emitting unit 120 corresponds to a “first light emitting unit” in the claims, and the green light LG corresponds to “first light of the first color” in the claims. The direction parallel to the optical axis ax1 corresponds to the “first direction”.

  Further, since the semiconductor laser 20R of the light emitting unit 120 is disposed on the focal plane M of the collimator lens 122a, the red light LR emitted from the semiconductor laser 20R is converted into parallel light by the collimator lens 122a, and the light Injection is performed in a direction D1 that is gradually separated from the axis ax1.

  The semiconductor laser 20B of the light emitting unit 120 is disposed on the opposite side of the semiconductor laser 20R across the focal position M1 of the focal plane M of the collimator lens 122a. Therefore, the blue light LB emitted from the semiconductor laser 20B is converted into parallel light by the collimator lens 122a, and emitted in a direction D2 that is different from the direction D1 and is gradually separated from the optical axis ax1. The

  In the present embodiment, the semiconductor laser 20R of the light emitting unit 120 corresponds to the “second light emitting portion” in the claims, and the red light LR is changed to “second light of the second color” in the claims. The direction D1 corresponds to “a second direction different from the first direction” in the claims.

As shown in FIG. 3, since the semiconductor laser 20G of the light emitting unit 220 is disposed at the focal position M1 of the collimator lens 222a, the green light LG emitted from the semiconductor laser 20G is parallel by the collimator lens 222a. And emitted in a direction parallel to the optical axis ax1.
In the present embodiment, the semiconductor laser 20G of the light emitting unit 220 corresponds to the “third light emitting portion” in the claims, and the green light LG is changed to “third light of the first color” in the claims. Equivalent to.

  Further, since the semiconductor laser 20R of the light emitting unit 220 is disposed on the focal plane M of the collimator lens 222a, the red light LR emitted from the semiconductor laser 20R is converted into parallel light by the collimator lens 222a, and the light Injected in the direction D1 gradually separated from the axis ax1.

  The semiconductor laser 20B of the light emitting unit 220 is disposed on the opposite side of the semiconductor laser 20R across the focal position M1 of the focal plane M of the collimator lens 222a. Therefore, the blue light LB emitted from the semiconductor laser 20B is converted into parallel light by the collimator lens 222a and emitted in the direction D2.

  In the present embodiment, the semiconductor laser 20R of the light emitting unit 220 corresponds to the “fourth light emitting portion” in the claims, and the red light LR corresponds to the “fourth light of the second color” in the claims. Equivalent to.

  According to this embodiment, the green light LG from the light emitting units 120 and 220 is emitted from the collimator lens array 22 in a direction parallel to the optical axis ax1, and the two red lights LR from the light emitting units 120 and 220 are collimated. The two blue lights LB from the light emitting units 120 and 220 are emitted from the meter lens array 22 in the direction D1, and are emitted from the collimator lens array 22 in the direction D2.

  According to this embodiment, each light emitting unit 20 adjusts the positional relationship of each of the semiconductor lasers 20R, 20G, and 20B with respect to the corresponding collimator lens, so that the progress of a plurality of color lights emitted from the plurality of collimator lenses. The direction can be different for each color. In the present embodiment, in any light emitting unit 20, the positional relationship of the semiconductor lasers 20R, 20G, and 20B with respect to the collimator lens is the same. Therefore, the collimator lens array 22 functions as a color separation optical system.

  As shown in FIG. 1, the green light LG emitted from each light emitting unit 20 travels in a direction parallel to the optical axis ax1 of the corresponding collimator lens 22a, and enters the light uniformizing optical system 3G. On the other hand, the red light LR emitted from each light emitting unit 20 travels in the direction D1 from the corresponding collimator lens 22a and enters the light uniformizing optical system 3R. The blue light LB emitted from each light emitting unit 20 travels in the direction D2 from the corresponding collimator lens 22a and enters the light uniformizing optical system 3B.

  The light homogenizing optical system 3G guides the green light LG emitted from the illumination device 2 to the light modulation device 4G. The light uniformizing optical system 3G includes a light uniformizing element 13G.

  In the present embodiment, the light homogenizing element 13G is composed of a diffraction element such as a computer generated hologram (CGH).

The positions of the light uniformizing element 13G and the light modulation device 4G are determined so that the first-order diffracted light of the green light LG is incident on the light modulation device 4G.
The light uniformizing element 13G has a rectangular light distribution as a whole, and the aspect ratio (aspect ratio) of this light distribution is the aspect ratio (aspect ratio) of the illuminated area (image forming area of the light modulation device 4G). ) To generate a diffracted light distribution that coincides with
Thereby, the light uniformizing element 13G can uniformize the luminance distribution (illuminance distribution) in the image forming region of the light modulation device 4G having a rectangular shape as the illuminated region.

  The light homogenizing optical system 3R guides the red light LR emitted from the illumination device 2 to the light modulation device 4R. The light uniformizing optical system 3R includes a light uniformizing element 13R and a first total reflection mirror 14R.

  The light uniformizing element 13R is composed of the CGH. The first total reflection mirror 14R is disposed in the optical path of the red light LR, and reflects the red light LR transmitted through the light uniformizing element 13R toward the light modulation device 4R.

The positions of the light uniformizing element 13R, the first total reflection mirror 14R, and the light modulation device 4R are determined so that the first-order diffracted light of the red light LR is incident on the light modulation device 4R.
The light uniformizing element 13R has a rectangular light distribution as a whole, and the aspect ratio (aspect ratio) of this light distribution is the aspect ratio (aspect ratio) of the illuminated area (image forming area of the light modulation device 4R). ) To generate a diffracted light distribution that coincides with.
As a result, the light uniformizing element 13R can uniformize the luminance distribution (illuminance distribution) in the image forming region of the light modulation device 4R having a rectangular shape as the illuminated region.

  The light homogenizing optical system 3B guides the blue light LB emitted from the illumination device 2 to the light modulation device 4B. The light homogenizing optical system 3B includes a light homogenizing element 13B and a second total reflection mirror 14B.

  The light homogenizing element 13B is composed of the CGH. The second total reflection mirror 14B is disposed in the optical path of the blue light LB, and reflects the blue light LB transmitted through the light uniformizing element 13B toward the light modulation device 4B.

The positions of the light uniformizing element 13B, the second total reflection mirror 14B, and the light modulation device 4B are determined so that the first-order diffracted light of the blue light LB is incident on the light modulation device 4B.
The light uniformizing element 13B has a rectangular light distribution as a whole, and the aspect ratio (aspect ratio) of this light distribution is the aspect ratio (aspect ratio) of the illuminated area (image forming area of the light modulation device 4B). ) To generate a diffracted light distribution that coincides with.
Thereby, the light uniformizing element 13B can uniformize the luminance distribution (illuminance distribution) in the image forming region of the light modulation device 4B having a rectangular shape as the illuminated region.

  The light modulation device 4R modulates the red light LR according to the image information, and forms image light corresponding to the red light LR. The light modulation device 4G modulates the green light LG according to the image information, and forms image light corresponding to the green light LG. The light modulation device 4B modulates the blue light LB according to the image information, and forms image light corresponding to the blue light LB.

  For example, a transmissive liquid crystal panel is used for the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B. A polarizing plate (not shown) is disposed on each of the incident side and the emission side of the liquid crystal panel.

  Further, a field lens 10R, a field lens 10G, and a field lens 10B are disposed on the incident side of the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B, respectively. The field lens 10R, the field lens 10G, and the field lens 10B collimate the red light LR, the green light LG, and the blue light LB incident on the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B, respectively.

  Image light from the light modulation device 4R, the light modulation device 4G, and the light modulation device 4B is incident on the combining optical system 5. The synthesis optical system 5 synthesizes image lights corresponding to the red light LR, green light LG, and blue light LB, respectively, and emits the synthesized image light toward the projection optical system 6. For example, a cross dichroic prism is used for the combining optical system 5.

  The projection optical system 6 includes a projection lens group, and enlarges and projects the image light combined by the combining optical system 5 toward the screen SCR. As a result, an enlarged color image is displayed on the screen SCR.

  According to the illuminating device 2 of this embodiment, since the collimator lens 22a provided corresponding to the light emitting unit 20 is used as a color separation optical system, a color separation optical system using a dichroic mirror becomes unnecessary. In a color separation optical system using a dichroic mirror, two dichroic mirrors are required to separate white light into red light, blue light, and green light. According to this embodiment, since a dichroic mirror is unnecessary, color separation of illumination light can be performed with a simple configuration while reducing costs.

In addition, since the light uniformizing elements 13R, 13G, and 13B that are diffractive elements are provided, the luminance distribution (illuminance distribution) in the light modulation devices 4R, 4G, and 4B, which are illuminated areas, can be easily uniformized.
Moreover, according to the projector 1 of this embodiment, since the illumination device 2 that does not require a color separation optical system using a dichroic mirror is provided, the projector 1 can be downsized.

In addition, this invention is not limited to the content of the said embodiment, In the range which does not deviate from the main point of invention, it can change suitably.
For example, in the above-described embodiment, the case where the semiconductor lasers 20R, 20G, and 20B are packaged has been described as an example. However, the present invention is not limited to this. Alternatively, the arrangement may be adopted.

  Moreover, although the case where a semiconductor laser is used as an example of the light emitting unit in the light source device 2A has been described in the above embodiment, an LED (light emitting diode) may be used. In addition, when using LED as a light emission part, what is necessary is just to use a lens integrator, a superimposition lens, or a rod integrator as a light uniformization optical system instead of a diffraction element as mentioned above.

  In the above embodiment, the light source device 2A has a plurality of light emitting units 20 as an example. However, the present invention is not limited to this, and the light source device 2A may be composed of only one light emitting unit 20. In this case, only one collimator lens 22a may be used.

  Moreover, in the said embodiment, although the projector 1 provided with the three light modulation apparatuses 4R, 4G, and 4B was illustrated, it is also possible to apply to the projector which displays a color image | video with one light modulation apparatus. Furthermore, the light modulation device is not limited to the above-described liquid crystal panel, and for example, a digital mirror device can be used.

  Moreover, although the example which mounted the illuminating device by this invention in the projector was shown in the said embodiment, it is not restricted to this. The lighting device according to the present invention can also be applied to lighting fixtures, automobile headlights, and the like.

  DESCRIPTION OF SYMBOLS 1 ... Projector, 2 ... Illumination device, 2A ... Light source device, 3R, 3G, 3B ... Light equalization optical system, 4R, 4G, 4B ... Light modulation device, 6 ... Projection optical system, 13R, 13G, 13B ... Light uniformity 20 ... light emitting unit, 22 ... collimator lens array, 22a ... collimator lens, 22a1 ... collimator lens (first collimator lens), 22a2 ... collimator lens (second collimator lens), 120 ... Light emitting unit (first light emitting unit), 220... Light emitting unit (second light emitting unit).

Claims (7)

A first light emitting unit that emits first light of a first color, and a second light emitting unit that emits second light of a second color different from the first color. A light source device having one light emitting unit;
A collimating optical system having a first collimator lens on which the first light and the second light are incident;
The first light and the second light are emitted from the first collimator lens in different directions. The light source device includes a third light emitting unit that emits third light of the first color, and a fourth light emitting unit that emits fourth light of the second color. The light emitting unit is further provided,
The collimating optical system further includes a second collimator lens on which the third light and the fourth light are incident,
The first light and the third light are emitted from the collimating optical system in a first direction, and the second light and the fourth light are emitted from the collimating optical system in a second direction. The lighting device according to claim 1, wherein the first light emitting unit, the second light emitting unit, the first collimator lens, and the second collimator lens are configured so as to be emitted. . The positional relationship between the first light emitting unit and the second light emitting unit in the first light emitting unit is the positional relationship between the third light emitting unit and the fourth light emitting unit in the second light emitting unit. The lighting device according to claim 2. The relative relationship between the first light emitting unit and the first collimator lens is the same as the relative relationship between the second light emitting unit and the second collimator lens. Lighting device. A first light homogenizing element on which the first color light emitted from the collimating optical system is incident;
A second light homogenizing element on which the light of the second color emitted from the collimating optical system is incident;
The lighting device according to claim 1, further comprising: The illumination device according to claim 5, wherein each of the first light uniformizing element and the second light uniformizing element is configured by a diffraction element. The lighting device according to any one of claims 1 to 6,
A light modulation device that forms image light by modulating light from the illumination device according to image information; and
A projection optical system that projects the image light.

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