JP5500235B2 - Illumination device and display device - Google Patents

Description

  The present disclosure relates to an illumination device that emits light including laser light, and a display device that displays an image using such an illumination device.

  An optical module, which is one of the main components of a projector (projection display device), generally includes an illumination optical system (illumination device) including a light source and a projection optical system (projection optical system) including a light modulation element. ing. In the field of such projectors, in recent years, small (palm-sized) and lightweight portable projectors called microprojectors have begun to spread. Conventionally, in this microprojector, an LED (Light Emitting Diode) is mainly used as a light source of a lighting device.

  On the other hand, recently, lasers have attracted attention as a new light source for lighting devices. For example, a projector using a gas laser is conventionally known as a projector using laser beams of three primary colors of red (R), green (G), and blue (B). Thus, projectors using a laser as a light source have been proposed in Patent Documents 1 and 2, for example. By using a laser as the light source, a projector having a wide color reproduction range and low power consumption can be obtained.

JP-A-55-65940 Japanese Patent Laid-Open No. 6-208089

  By the way, when a diffusing surface is irradiated with coherent light such as laser light, a pattern on a spot that cannot be seen with normal light is observed. Such a pattern is called a speckle pattern. This speckle pattern is generated because light scattered at each point on the diffusing surface interferes with each other in a random phase relationship according to microscopic unevenness on the surface.

  Here, in a projector using the above laser as a light source, such a speckle pattern (interference pattern) is superimposed on a display image on a screen. For this reason, it is recognized by human eyes as intense random noise, and the display image quality deteriorates. As described above, the generation of speckle patterns is a common problem when using a coherent laser beam as a light source. Conventionally, various methods for reducing the generation of speckle patterns (speckle noise) have been proposed. Attempts have been made.

  For example, in Patent Document 1, in a projector using a laser as a light source, the screen is slightly vibrated using a piezoelectric element in order to reduce the occurrence of such a speckle pattern. In general, the human eye and brain cannot discern flickering of an image within about 20 to 50 ms. That is, the images within that time are integrated and averaged in the eye. Therefore, by superimposing a large number of independent speckle patterns on the screen within this time, the speckle noise is intended to be averaged to the extent that the human eye does not care. However, with this method, there is a problem that the size of the apparatus is increased because it is necessary to vibrate the large screen itself.

  On the other hand, in Patent Document 2, the position of the speckle pattern is displaced at high speed on the screen by mechanically rotating the diffusing element so that speckle noise is not detected by human eyes. However, since this method diffuses light using a diffusing element, there is a problem in that the light use efficiency decreases.

  The present disclosure has been made in view of such problems, and an object thereof is to provide an illumination device and a display device capable of reducing the generation of interference patterns while reducing the size and improving the light use efficiency. It is in.

An illumination device of the present disclosure includes a light source unit including a laser light source, an optical element disposed on an optical path along which laser light from the laser light source travels, a fly-eye lens that emits illumination light, an optical element, and a fly-eye. A drive unit that changes at least one of the incident position and the incident angle of the laser light in the incident surface of the fly-eye lens by displacing the relative position with the lens is provided. The optical element has a first optical surface that emits the incident laser beam while converging it, and a second optical surface that emits the incident laser beam while diverging it.

  A display device according to the present disclosure includes the illumination device according to the present disclosure and a light modulation element that modulates illumination light from the illumination device based on a video signal.

  In the illumination device and the display device according to the present disclosure, the relative position between the optical element disposed on the optical path in which the laser light travels and the fly-eye lens that emits the illumination light is displaced, thereby causing the laser light. Generation of interference patterns is reduced. In addition, in the incident surface of the fly-eye lens, at least one of the incident position and the incident angle (incident position, incident angle, or both the incident position and incident angle) of the laser light is changed, so that the above-described relative Even if the position is displaced, the optical loss at the time of incidence from the optical element to the fly-eye lens is reduced or avoided.

  According to the illumination device and the display device of the present disclosure, the fly-eye lens is displaced by displacing the relative position between the optical element disposed on the optical path in which the laser light travels and the fly-eye lens that emits the illumination light. Since at least one of the incident position and the incident angle of the laser beam is changed within the incident surface of the laser beam, the laser beam is reduced or avoided while reducing the optical loss when entering the fly-eye lens from the optical element. It is possible to reduce the occurrence of interference patterns due to the above. Therefore, it is possible to reduce the generation of interference patterns (improving display image quality) while reducing the size and improving the light utilization efficiency.

It is a figure showing the whole structure of the display apparatus which concerns on one embodiment of this indication. FIG. 2 is a perspective view schematically illustrating a detailed configuration of the prism array illustrated in FIG. 1. It is a figure showing the whole structure of the display apparatus which concerns on a comparative example. It is a schematic diagram for demonstrating the effect | action of the prism array shown in FIG. It is a schematic diagram for demonstrating the beam scan by the vibration of a prism array. It is a schematic diagram for demonstrating the relationship between the pitch of a prism array, and the pitch of a fly eye lens. It is a schematic diagram for demonstrating the generation | occurrence | production principle of a non-irradiation area | region. 10 is a cross-sectional view schematically illustrating a configuration of a prism array according to Modification 1. FIG. It is a figure showing the principal part structure of the illuminating device which concerns on the modification 2. It is a figure showing the principal part structure of the illuminating device which concerns on the modification 3. It is a figure which represents typically the structure of the optical element which concerns on the modification 4. It is a schematic diagram showing the detailed structure of the optical element shown in FIG. It is a figure showing an example of each parameter shown in FIG. It is a schematic diagram for demonstrating an effect | action of the optical element shown in FIG. It is a figure which represents typically the structure of the optical element which concerns on the modification 5. It is a figure which represents typically the structure of the optical element which concerns on the modification 6. As shown in FIG. It is a figure showing the principal part structure of the illuminating device which concerns on the modification 7. It is a figure showing the principal part structure of the illuminating device which concerns on the modification 8. It is a figure which represents typically the structure of the optical element which concerns on another modification. It is a figure which represents typically the structure of the optical element which concerns on another modification. It is a figure which represents typically the structure of the optical element which concerns on another modification.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The description will be given in the following order.

1. Embodiment (example using prism array as optical element)
2. Modified example Modified example 1 (example in which a diffraction grating is provided in a prism array)
Modification 2 (example using a diffraction element as an optical element)
Modification 3 (example using a lens (collimator lens) as an optical element)
Modifications 4 and 5 (examples using optical elements having convex and concave curved surfaces)
Modification 6 (example using a microlens array as an optical element)
Modification 7 (example in which a plurality of optical elements are provided along the optical axis)
Modification 8 (Method for changing the relative positional relationship between the optical element and the fly-eye lens)
Other variations

<Embodiment>
[Overall Configuration of Display Device 3]
FIG. 1 illustrates an overall configuration of a display device (display device 3) according to an embodiment of the present disclosure. The display device 3 is a projection type display device that projects an image (image light) onto a screen 30 (projected surface), and displays an image using the illumination device 1 and illumination light from the illumination device 1. An optical system (display optical system).

(Lighting device 1)
The illumination device 1 includes a red laser 11R, a green laser 11G, a blue laser 11B, lenses 12R, 12G, and 12B, dichroic prisms 131 and 132, a prism array 14, a drive unit 15, a collimator lens 16, a fly-eye lens 17, and a condenser lens 18. It has. In addition, Z0 shown in the figure represents an optical axis.

  The red laser 11R, the green laser 11G, and the blue laser 11B are three types of light sources that emit red laser light, green laser light, and blue laser light, respectively. A light source unit is configured by these laser light sources, and here, these three types of light sources are all laser light sources. Each of the red laser 11R, the green laser 11G, and the blue laser 11B includes, for example, a semiconductor laser, a solid laser, or the like. For example, when each of these laser light sources is a semiconductor laser, as an example, the wavelength of the red laser light is about λr = 600 to 700 nm, the wavelength of the green laser light is about λg = 500 to 600 nm, and the wavelength of the blue laser light is λb = 400. About 500 nm.

  The lenses 12R and 12G collimate the red laser light emitted from the red laser 11R and the green laser light emitted from the green laser 11G (as parallel lights) and combine them with the dichroic prism 131 (coupled lens). ). Similarly, the lens 12B is a lens (coupled lens) for collimating the laser light emitted from the blue laser 11B (as parallel light) and coupling it with the dichroic prism 132. Here, each of the incident laser beams is collimated by these lenses 12R, 12G, and 12B (and is made parallel light), but this is not a limitation, and the lenses 12R, 12G, and 12B do not collimate. (It does not have to be parallel light). However, it can be said that collimation as described above is more desirable because the size of the apparatus can be reduced.

  The dichroic prism 131 is a prism that selectively transmits the red laser light incident through the lens 12R and selectively reflects the green laser light incident through the lens 12G. The dichroic prism 132 is a prism that selectively transmits the red laser light and the green laser light emitted from the dichroic prism 131 while selectively reflecting the blue laser light incident through the lens 12B. As a result, color synthesis (optical path synthesis) is performed on the red laser light, the green laser light, and the blue laser light.

  The prism array 14 is disposed on the optical path between the light source and the fly-eye lens 17 (on the optical path of the laser light; specifically, on the optical path between the dichroic prism 132 and the collimator lens 16). This corresponds to a specific example of “optical element” in the disclosure. The prism array 14 is an optical element for reducing speckle noise (interference pattern), which will be described later, and the laser light traveling on the optical axis Z0 shown in the figure passes through the prism array 14. Yes.

FIG. 2 is a perspective view schematically showing the detailed configuration of the prism array 14. The prism array 14 includes a plurality of (here, n / 2 (n: integer greater than or equal to 2)) prisms 140 arranged along the Y-axis direction. Each prism 140 has a pair of inclined surfaces each extending in the X-axis direction on the laser beam emission side (+ Z-axis side). That is, these prisms 140 are arranged side by side along a direction (Y-axis direction) orthogonal to the extending direction (X-axis direction) of the pair of inclined surfaces in the light emission surface (XY plane). Yes. Specifically, the first prism 140 has two pairs of inclined surfaces (first surfaces) S ₁ and two inclined surfaces (second surfaces) S ₂ in order in the negative direction of the Y axis in the figure. The prism 140 of the eye has a pair of inclined surfaces (third surface) S ₃ and an inclined surface (fourth surface) S ₄ ... (N / 2) th prism 140 has a pair of inclined surfaces S _n−1 ( the (n-1) plane) and the inclined surface (the n-th surface) S _n, respectively have. As a result, each prism 140 has a triangular prism shape (pitch in the Y-axis direction (prism pitch): d, inclination angle of each inclined surface: θ) extending along the X-axis direction. Mountain portions (convex portions) and valley portions (concave portions) are alternately formed. In this example, the convex portion (inclined surface) is provided on the exit surface side of each prism 140. However, the present invention is not limited to this, and at least one of the entrance surface and the exit surface of each prism 14 is provided. What is necessary is just to be provided. The detailed operation of the prism array 14 will be described later (FIGS. 4 to 7).

  The drive unit 15 displaces the relative position between the prism array 14 and the fly-eye lens 17, so that at least one of the incident position and the incident angle of the laser light (incident on the incident surface of the fly-eye lens 17). Position, incident angle, or both incident position and incident angle). In particular, in the present embodiment, the drive unit 15 vibrates (microvibrates) the prism array 14 as shown in FIG. 1 (specifically, Y is the arrangement direction of the prisms 140 shown in FIG. 2). The relative position is displaced by oscillating along the axial direction. The drive unit 15 includes, for example, a coil and a permanent magnet (for example, a permanent magnet made of a material such as neodymium (Nd), iron (Fe), or boron (boron; B)). The displacement of the relative position and the displacement of at least one of the incident position and the incident angle are, for example, periodic displacements (changes). However, in this case, the displacement is not limited to other displacements (changes). ) Method, and the same applies to all the following examples. Moreover, as a driving method by this drive part 15, the method of reciprocating the said relative position with the drive frequency more than predetermined frequency (for example, 15 Hz) is mentioned, for example.

  The collimator lens 16 is disposed on the optical path between the prism array 14 and the fly-eye lens 17 and is a lens for collimating the light emitted from the prism array 14 into parallel light.

  The fly-eye lens 17 is an optical member (integrator) in which a plurality of lenses (a plurality of unit lenses 170 described later) are two-dimensionally arranged on a substrate, and an incident light beam is spatially divided according to the arrangement of these lenses. Are emitted. Thereby, the emitted light from the fly-eye lens 17 is made uniform (in-plane intensity distribution is made uniform) and emitted as illumination light. The fly-eye lens 17 corresponds to a specific example of “optical member” in the present disclosure.

  The condenser lens 18 is a lens for collecting incident light (illumination light) that is made uniform by the fly-eye lens 17.

(Display optical system)
The display optical system described above is configured by using a polarization beam splitter (PBS) 22, a reflective liquid crystal element 21, and a projection lens 23 (projection optical system).

  The polarization beam splitter 22 is an optical member that selectively transmits specific polarized light (for example, s-polarized light) and selectively reflects the other polarized light (for example, p-polarized light). As a result, the illumination light (for example, s-polarized light) from the illumination device 1 is selectively reflected and enters the reflective liquid crystal element 21, and the image light (for example, p-polarized light) emitted from the reflective liquid crystal modulation element 21. The light is selectively transmitted and incident on the projection lens 23.

  The reflective liquid crystal element 21 is a light modulation element that emits video light by reflecting the illumination light from the illumination device 1 while modulating it based on a video signal supplied from a display control unit (not shown). At this time, the reflection type liquid crystal element 21 performs reflection so that each polarized light (for example, s-polarized light or p-polarized light) is different between the incident time and the emitted time. Such a reflective liquid crystal element 21 is made of a liquid crystal element such as LCOS (Liquid Crystal On Silicon).

  The projection lens 23 is a lens for projecting (enlarging and projecting) illumination light (video light) modulated by the reflective liquid crystal element 21 onto the screen 30.

[Operation and effect of display device 3]
(1. Display operation)
In the display device 3, first, light (laser light) emitted from the red laser 11 R, the green laser 11 G, and the blue laser 11 B in the illumination device 1 is collimated by the lenses 12 R, 12 G, and 12 B, and becomes parallel light. . Next, the laser beams (red laser beam, green laser beam, and blue laser beam) that have been converted into parallel light in this way are subjected to color synthesis (optical path synthesis) by the dichroic prisms 131 and 132. Each of the laser beams that have undergone optical path synthesis passes through the prism array 14, and then is collimated by the collimator lens 16 to become parallel light and enters the fly-eye lens 17. The incident light is made uniform by the fly-eye lens 17 (in-plane intensity distribution is made uniform) and emitted, and then collected by the condenser lens 18. In this way, illumination light is emitted from the illumination device 1.

  Next, the illumination light is selectively reflected by the polarization beam splitter 22 and enters the reflective liquid crystal element 21. In the reflective liquid crystal element 21, the incident light is reflected while being modulated based on the video signal, and is emitted as video light. Here, in this reflection type liquid crystal element 21, since each polarized light at the time of incidence is different from that at the time of emission, the image light emitted from the reflection type liquid crystal element 21 is selectively transmitted through the polarization beam splitter 22 and projected. The light enters the lens 23. The incident light (image light) is projected (enlarged projection) onto the screen 30 by the projection lens 23.

  At this time, each of the red laser 11R, the green laser 11G, and the blue laser 11B sequentially emits light in a time division manner (pulse emission), and emits each laser beam (red laser beam, green laser beam, and blue laser beam). In the reflective liquid crystal element 21, the laser light of the corresponding color is sequentially modulated in a time division manner based on the video signal of each color component (red component, green component, blue component). As a result, a color video display based on the video signal is performed on the display device 3.

(2. Action of characteristic parts)
Next, the operation of the characteristic part of the present disclosure (the operation of the lighting device 1) will be described in detail in comparison with a comparative example.

(2-1. Comparative example)
FIG. 3 illustrates an overall configuration of a display device (display device 100) according to a comparative example. The display device 100 of this comparative example is a projection type display device that projects video light onto the screen 30 as in the display device 3 of the present embodiment. The display device 100 includes a red laser 101R, a green laser 101G, a blue laser 101B, dichroic mirrors 102R, 102G, and 102B, a diffusion element 103, a motor (drive unit) 104, a lens 105, a light modulation element 106, and a projection lens 107. Yes.

  In this display device 100, the laser beams of the respective colors emitted from the red laser 101R, the green laser 101G, and the blue laser 101B undergo color synthesis (optical path synthesis) in the dichroic mirrors 102R, 102G, and 102B, and enter the diffusion element 103. . The incident light is diffused by the diffusing element 103 and then irradiated to the light modulation element 106 as illumination light by the lens 105. In the light modulation element 106, the illumination light is reflected while being modulated based on the video signal, and is emitted as video light. Then, the image light is projected (enlarged projection) onto the screen 30 by the projection lens 107, whereby a color image display based on the image signal is performed on the display device 100.

  By the way, when a diffusing surface is irradiated with coherent light such as laser light, a pattern on a spot that cannot be seen with normal light is observed. Such a pattern is called a speckle pattern. This speckle pattern is generated because light scattered at each point on the diffusing surface interferes with each other in a random phase relationship according to microscopic unevenness on the surface.

  Here, in a projector using a laser light source like the display device 100 of the comparative example, such a speckle pattern (interference pattern) is superimposed on the display image on the screen. Therefore, if it is as it is, it will be recognized by the human eye as intense random noise, and the display image quality will deteriorate.

  Therefore, in a projector using a laser light source, in order to reduce the occurrence of such a speckle pattern (speckle noise), a method of minutely vibrating the screen can be considered. In general, the human eye and brain cannot discern flickering of an image within about 20 to 50 ms. That is, the images within that time are integrated and averaged in the eye. Therefore, by superimposing a large number of independent speckle patterns on the screen within this time, the speckle noise is intended to be averaged to the extent that the human eye does not care. However, in this method, since the large screen itself needs to be minutely vibrated, the apparatus configuration becomes large. At the same time, there are concerns about increased power consumption and noise problems.

  Therefore, in the display device 100 of the comparative example, the generation of speckle noise is reduced by mechanically rotating the diffusion element 103 by the motor 104 and displacing the position of the speckle pattern on the screen 30 at high speed. Yes. However, in this method, since the light incident on the diffusing element 103 is diffused by the diffusing element 103, the light use efficiency is lowered.

(2-2. The present embodiment)
On the other hand, in the illuminating device 1 of this Embodiment, the above problem is solved using the prism array 14 as follows.

First, in the prism array 14, light incident on each prism 140 is emitted from a pair of inclined surfaces as follows. That is, as shown in FIG. 4, on the pair of inclined surfaces of each prism 140, the position of the incident light and the surface separated by a predetermined distance from the prism array 14 (here, on the incident surface of the fly-eye lens 17). The emitted light is emitted so that the positions of the emitted light in FIG. Specifically, in the first prism 140 described above in the prism array 14, the incident light incident position and the outgoing light on the incident surface of the fly-eye lens 17 are between the inclined surface S ₁ and the inclined surface S _2. Are replaced with each other. That is, the outgoing light from the inclined surface S ₁ is emitted toward the incident position of the incident light on the inclined surface S ₂ (the lower side in the outgoing surface of the first prism 140), while from the inclined surface S _2. Is emitted toward the incident position of the incident light on the inclined surface S ₁ (upper side in the emission surface of the first prism 140). Similarly, in the above-described (n / 2) th prism 140, between the inclined surface S _n-1 and the inclined surface S _n, and the incident position of the incident light, the outgoing light on the incident surface of the fly-eye lens 17 Are replaced with each other. That is, light emitted from the inclined surface S _n-1, while that emitted toward the incident position of incident light on the inclined surface S _{n ((n} / 2) lower side in the exit plane of th prism 140) , light emitted from the inclined surface S _n is emitted toward the incident position of incident light on the inclined surface _{S n-1 ((n /} 2) the upper side in the exit plane of th prism 140). Note that the switching operation of the positions of the incident light and the outgoing light can be arbitrarily adjusted by setting the prism pitch d and the inclination angle θ shown in FIG.

  Then, the drive unit 15 displaces the relative position between the prism array 14 and the fly-eye lens 17. Specifically, the drive unit 15 according to the present embodiment, for example, as shown by an arrow P1 in FIG. 5, the prism array 14 is arranged in the direction in which the prisms 140 are arranged in the plane orthogonal to the optical axis Z0 (Y axis). The relative position is displaced by oscillating along the direction. That is, the positions of the emitted light from the inclined surfaces of the respective prisms 140 (emitted light emitted so that the positions of the pair of inclined surfaces are interchanged with each other) are also indicated by arrows P21 and P21 in FIG. Is displaced (shifted) along the Y-axis direction. As a result, a beam scan is performed on the incident surface of the fly-eye lens 17 by the incident light from each prism 140 in the prism array 14. As a result, the generation of speckle noise (interference pattern) due to laser light is reduced by the above principle (multiplexing of speckle patterns (time average)).

  In the present embodiment, the drive unit 15 includes the prism array 14 and the fly-eye lens 17 so that at least one of the incident position and the incident angle of the laser light changes within the incident surface of the fly-eye lens 17. Relative position (here, the prism array 14 itself) is displaced (vibrated). Thereby, even if the displacement (beam scanning) of the relative position described above is performed, the light loss at the time of entering the fly-eye lens 17 from the prism array 14 is reduced or avoided. That is, unlike the method of the above comparative example, when speckle noise is reduced by using speckle noise multiplexing (time average), laser light loss is reduced or avoided to a minimum. .

By the way, in this prism array 14, for example, as shown in FIG. 6, the length in the arrangement direction (Y-axis direction) on the inclined surface of the prism 140 is Pa, the distance between the prism array 14 and the fly-eye lens 17 is D, When the refraction angle in the light emitted from the prism array 14 is φ, the following equation (1) is established. In this case, it can be said that it is desirable to satisfy the following expression (2).
Pa≈ (D × tanφ) (1)
Pa = (D × tanφ) (2)

At this time, as shown in FIG. 6, it is desirable that the following expression (3) is satisfied, where Pf is the pitch of the unit lenses in the fly-eye lens 17. In other words, the length Pa in the arrangement direction on the inclined surface of the prism 140 is different from the pitch Pf of the unit lenses in the fly-eye lens 17 and is an integral multiple (an integral multiple of 2 or more) of the pitch Pf. It is desirable to avoid it.
Pa ≠ (m × Pf) (m: an integer of 1 or more) (3)

  This is due to the following reason. That is, by setting the length Pa in the prism 140 and the pitch Pf in the fly-eye lens 17 so as to satisfy the above expression (3), generation of a non-irradiation region on the incident surface of the fly-eye lens 17 is avoided. Because it is done. In other words, generation of a non-irradiation region is avoided on the reflective liquid crystal element 21 which is a conjugate point.

  Specifically, when the positions of the incident light and the emitted light are switched by the prism array 14 described above, the accuracy of the prism array 14 and the displacement (displacement displacement) of the distance from the prism array 14 to the fly-eye lens 17 are changed. ), A non-irradiation region may be generated on the fly-eye lens 17. At that time, if the above expression (3) is not satisfied (Pa = (m × Pf) is satisfied), such a non-irradiation region is periodically generated. That is, since the fly-eye lens 17 makes the in-plane intensity distribution uniform, a blank area (non-irradiation area) may occur in a specific portion in the irradiated surface if the above equation (3) is not satisfied. There is sex. Then, for example, as shown in FIG. 7, a non-irradiation region or illuminance unevenness occurs in the irradiation region after emission from the fly-eye lens 17. In this example, a non-irradiation region 211 is partially generated on the reflective liquid crystal element 21 in addition to the irradiation region 210, resulting in uneven illuminance. Specifically, if the solid line in FIG. 7 represents a light beam that passes through the non-irradiated region on the fly-eye lens 17, the periodic non-irradiated region on the fly-eye lens 17 is a reflective liquid crystal element. 21, a partial non-irradiation region 211 has been generated. On the other hand, by setting so as to satisfy the above expression (3), it is possible to avoid the occurrence of uneven illuminance (display unevenness) due to the generation of the non-irradiation region 211.

  As described above, in the present embodiment, the relative position between the prism array 14 through which the laser light passes and the fly-eye lens 17 that emits the illumination light is displaced, so that the incident surface of the fly-eye lens 17 is within the incident surface. Since at least one of the incident position and the incident angle of the laser light is changed, the light loss caused by the incidence from the prism array 14 to the fly-eye lens 17 is reduced or avoided, and is caused by the laser light. Generation of interference patterns (speckle noise) can be reduced. Therefore, it is possible to reduce the generation of interference patterns (improving display image quality) while reducing the size and improving the light utilization efficiency.

<Modification>
Subsequently, modified examples (modified examples 1 to 8) of the above-described embodiment will be described. In addition, the same code | symbol is attached | subjected to the same thing as the component in embodiment, and description is abbreviate | omitted suitably.

[Modification 1]
FIG. 8 schematically shows a configuration of an optical element (prism array 14 </ b> A) according to Modification 1 in a cross-sectional view. The prism array 14A of the present modification is such that a diffraction grating 141 (diffraction grating structure) is provided on the inclined surface of each prism 140 in the prism array 14 of the above embodiment, and the other configurations are the same. It has become.

  The diffraction grating 141 generates diffracted light Ld (for example, the 0th-order diffracted light, the + 1st-order diffracted light, the −1st-order diffracted light, etc. shown in the figure) by diffracting the incident light Lin on the inclined surface of the prism 140. The light is emitted.

  In this modification using the prism array 14A having such a diffraction grating 141, it is possible to avoid the occurrence of illuminance unevenness (display unevenness) due to the generation of a non-irradiated region without setting so as to satisfy the above-described equation (3). It becomes possible to do. That is, it is possible to avoid the occurrence of illuminance unevenness (display unevenness) due to the generation of the non-irradiation region without setting the length Pa in the prism 140 and the pitch Pf in the fly-eye lens 17 so as to satisfy the expression (3). It becomes possible.

[Modification 2]
FIG. 9 illustrates a main configuration (a part of the configuration) of the illumination device (illumination device 1B) according to Modification 2. The illumination device 1B of the present modification is provided with a diffraction element 14B described below as a specific example of the “optical element” in the present disclosure, instead of the prism array 14 described in the above embodiment. The configuration is the same as that of the lighting device 1.

  The diffractive element 14B is an optical element that diffracts incident light and emits it to the collimator lens 16 and the fly-eye lens 17 as shown in the figure.

  In the present modification, the drive unit 15 displaces the relative position between the diffraction element 14B and the fly-eye lens 17, so that the incident position and the incident angle of the laser light are changed within the incident surface of the fly-eye lens 17. Change at least one of them. Specifically, the drive unit 15 causes the diffraction element 14B to vibrate (microvibration) along the direction (Z-axis direction) of the optical axis (optical axis Z0) of the diffraction element 14B and the fly-eye lens 17. The relative position is displaced.

  In this way, the diffraction action of incident light (outgoing of diffracted light) by the diffractive element 14B and the vibration operation in the direction of the optical axis of the diffractive element 14B by the drive unit 15 are performed, which is the same as in the above embodiment. Beam scanning is performed. That is, a beam scan is performed on the incident surface of the fly-eye lens 17 by the incident light from the diffraction element 14B. As a result, similar to the above-described embodiment, the generation of speckle noise (interference pattern) due to laser light is reduced by multiplexing of speckle patterns (time average).

  Also in this modification, the drive unit 15 includes the diffractive element 14B and the fly-eye lens 17 so that at least one of the incident position and the incident angle of the laser light changes in the incident surface of the fly-eye lens 17. Relative position (here, the diffraction element 14B itself) is displaced (vibrated). Therefore, in the present modification as well, as in the above-described embodiment, even if the relative position displacement (beam scan) is performed, the light loss at the time of incidence on the fly-eye lens 17 from the diffraction element 14B is reduced or reduced. Avoided.

  Here, as shown in FIG. 9, the m-order light (m-order diffracted light) of the diffracted light from the diffractive element 14 </ b> B is the height from the optical axis Z <b> 0 at the positions of the collimator lens 16 and the fly-eye lens 17. Let (distance in the Y-axis direction) be H and T, respectively. The diffraction angle of this m-order light is θm, the distance between the diffraction element 14B and the collimator lens 16 is Z1, the distance between the collimator lens 16 and the fly-eye lens 17 is D, and the combined focal length of the collimator lens 16 is f (FIG. (Not shown), the following equation (4) holds. For this reason, assuming that the amplitude at the time of vibration of the diffraction element 14B is ΔL, the amount of change ΔT of the height T on the fly-eye lens 17 can be expressed by the following equation (5). Therefore, in this modification, the amplitude ΔL at the time of vibration may be set so that the amount of change ΔT is a value within a range effective for reducing speckle noise. The diffraction angle θm described above can be expressed by the following equation (6), where p is the pitch of the diffraction grating in the diffraction element 14B, and λ is the wavelength of the incident light. Therefore, in this modification, when the beam shift amount effective for speckle reduction on the fly-eye lens 17 is S, the following conditional expression (Equation (7)) holds for this beam shift amount S: Become.

  Also in the illumination device 1B having such a configuration and a display device using the same, it is possible to obtain the same effect by the same operation as in the above embodiment. That is, it is possible to reduce the generation of interference patterns (improving display image quality) while reducing the size and improving the light utilization efficiency.

[Modification 3]
FIG. 10 illustrates a main configuration (a part of the configuration) of the illumination device (illumination device 1C) according to Modification 3. As a specific example of the “optical element” in the present disclosure, the illumination device 1 </ b> C according to the present modification is provided with a lens (collimator lens 14 </ b> C) described below instead of the prism array 14 described in the above embodiment. Other configurations are the same as those of the lighting device 1.

  As shown in the drawing, the collimator lens 14C collimates the incident light from the dichroic prism 132 into parallel light, and is an NA conversion lens having positive power.

  In this modification, the drive unit 15 displaces the relative position between the collimator lens 14 </ b> C and the fly-eye lens 17, thereby changing the incident position and the incident angle of the laser light on the incident surface of the fly-eye lens 17. Change at least one of them. Specifically, the driving unit 15 vibrates the collimator lens 14C along an in-plane direction (XY plane direction) orthogonal to the optical axis (optical axis Z0) of the collimator lens 14C and the fly-eye lens 17. The relative position is displaced by (microvibration).

  In this way, the collimating action of the incident light by the collimator lens 14C and the vibration operation (eccentric action) in the in-plane direction orthogonal to the optical axis direction of the collimator lens 14C by the drive unit 15 are performed. A beam scan similar to that in the above embodiment is performed. That is, a beam scan is performed on the incident surface of the fly-eye lens 17 by the incident light from the collimator lens 14C (see arrow P3 in FIG. 10). As a result, similar to the above-described embodiment, the generation of speckle noise (interference pattern) due to laser light is reduced by multiplexing of speckle patterns (time average).

  Also in this modification, the driving unit 15 collimator lens 14 </ b> C and the fly-eye lens 17 so as to change at least one of the incident position and the incident angle of the laser light within the incident surface of the fly-eye lens 17. Relative position (here, the collimator lens 14C itself) is displaced (vibrated). Accordingly, in the present modification as well, in the same way as in the above-described embodiment, even when the relative position displacement (beam scan) is performed, the light loss at the time of incidence from the collimator lens 14C to the fly-eye lens 17 is reduced or reduced. Avoided.

  Here, as shown in FIG. 10, the eccentricity in the collimator lens 14C is A, the emission angle of the emitted light from the collimator lens 14C when this eccentricity A is given is φ, and the focal length of the collimator lens 14C is Assuming f, the following equation (8) is established. Also, assuming that the distance between the collimator lens 14C and the fly-eye lens 17 is D, in this modification, the following conditional expression ((9) is applied to the beam shift amount S effective for speckle reduction on the fly-eye lens 17. ) Formula) holds. Therefore, with these expressions (8) and (9), in the present modification, the following conditional expression (expression (10)) is established for the beam shift amount S described above.

  Also in the lighting device 1C having such a configuration and a display device using the same, it is possible to obtain the same effect by the same operation as in the above embodiment. That is, it is possible to reduce the generation of interference patterns (improving display image quality) while reducing the size and improving the light utilization efficiency.

  In this modification, the collimator lens 14C has been described as an example of the lens as the “optical element”. However, the present invention is not limited to this, and other lenses may be used. Specifically, the entire optical system may have a positive power, and the optical system may be constructed using a plurality of lenses including an NA conversion lens having a negative power.

[Modification 4]
(Configuration of optical element 14D)
FIG. 11 schematically illustrates the configuration of an optical element (an optical element 14D) according to Modification 4. The optical element 14D of this modification has an uneven surface having a periodic corrugated structure on the light exit surface side. Here, FIG. 11A shows an XY plane configuration of the optical element 14D and a cross-sectional configuration along the line II-II in the drawing, and FIG. 11B is a symbol in FIG. 11A. This corresponds to the enlarged view of the portion indicated by G1.

  As shown in FIG. 11B, the optical element 14D has a first optical surface 14D1 made of a convex curved surface and a second optical surface 14D2 made of a concave curved surface arranged alternately on the light emitting surface side ( 1-dimensional array). Here, the pitch of the first optical surface 14D1 is P (+), the radius of curvature of the first optical surface 14D1 is R (+), the pitch of the second optical surface 14D2 is P (−), and the second optical surface 14D2 Is shown as R (-).

  The first optical surface 14D1 and the second optical surface 14D2 are respectively inclined with respect to the X axis and the Y axis (the arrangement direction of the unit lenses 170 in the fly-eye lens 17 described later). In other words, the extending direction of the first optical surface 14D1 and the second optical surface 14D2 and the arrangement direction of the unit lenses 170 described above are inclined with respect to each other. Here, as an example, the inclination angle α between the extending direction of the first optical surface 14D1 and the second optical surface 14D2 and the X axis is 45 °.

  Here, for example, as schematically shown in FIG. 12, the first optical surface 14D1 has a function of emitting the incident laser light while converging it, while the second optical surface 14D2 diffuses the incident laser light. And has a function of emitting light. In the optical element 14D, the optical path of the convergent light emitted from the first optical surface 14D1 and the optical path of the divergent light emitted from the second optical surface 14D2 are changed continuously (densely). The first optical surface 14D1 and the second optical surface 14D2 are smoothly connected. Note that F (+) shown in FIG. 12 represents the focal length on the first optical surface 14D1, and F (−) represents the focal length on the second optical surface 14D2.

  Further, as shown in FIG. 12, the angle formed by the traveling direction of the light emitted from the optical element 14D and the optical axis (here, the Z axis) of the fly-eye lens 17 (the angle θ (+) formed by the convergent light, divergence). The maximum value of the angle θ (−)) formed by light is θmax, and the allowable incident angle in the fly-eye lens 17 is θth. Then, in this optical element 14D, it is set to satisfy the conditional expression of θmax ≦ θth.

  The various parameters in the optical element 14D are set to values as shown in FIG. 13, for example. Here, as shown in FIG. 12, the LP is when the light flux width of the convergent light emitted from the first optical surface 14D1 and the light flux width of the divergent light emitted from the second optical surface 14D2 are equal to each other. This represents the distance between the plane (when both are at the pitch P) and the optical element 14D.

(Operation and effect of optical element 14D)
In the optical element 14D having such a configuration, for example, as shown in FIGS. 14A to 14C, relative to the fly-eye lens 17 from the reference position along the + Y axis direction and the −Y axis direction. The following operations and effects can be obtained by driving the positions so as to be displaced. 14A to 14C respectively show the convergent light beam region 17a and the diffused light beam region 17b on the plane separated from the optical element 14D by the distance LP, respectively, in each unit lens in the fly-eye lens 17. This is schematically shown by overlapping with 170. 14D to 14F schematically show the convergent light beam region 17a and the diffused light beam region 17b in the region on the unit lens 170 indicated by the thick line in FIGS. 14A to 14C, respectively. It is shown in.

  That is, by driving the optical element 14D so as to vibrate along the Y axis, for example, as shown in FIGS. 14D to 14F, the convergent light flux region within the region on each unit lens 170 is obtained. 17a and the diffused light beam region 17b are alternately switched. Therefore, also in the illuminating device and the display device using the optical element 14D having such a configuration, the same effect can be obtained by the same operation as in the above-described embodiment and the like. That is, it is possible to reduce the generation of interference patterns (improving display image quality) while reducing the size and improving the light utilization efficiency.

  In this modification, the extending direction of the first optical surface 14D1 and the second optical surface 14D2 of the optical element 14D and the arrangement direction of the unit lenses 170 of the fly-eye lens 17 are inclined with respect to each other. The following effects can also be obtained. That is, it is possible to reduce crosstalk in the boundary area between the boundary region between the unit lenses 170 and the convergent light beam and the diffused light beam.

  In the optical element 14D of the present modification, the case where the wave structure is formed on the light exit surface side has been described. However, the wave is formed on the light entrance surface side and on both the light entrance surface side and the light exit surface side. A mold structure may be formed.

[Modification 5]
FIG. 15 schematically illustrates the configuration of an optical element (an optical element 14E) according to Modification 5. The optical element 14E of this modification has an uneven surface having a periodic corrugated structure on the light exit surface side. Here, FIG. 15A shows an XY plane configuration of the optical element 14E and a cross-sectional configuration taken along lines III-III and IV-IV in the drawing, and FIGS. Respectively correspond to enlarged views of portions indicated by reference numerals G2 and G3 in FIG.

  The optical element 14E has a structure in which first optical surfaces 14D1 made of convex curved surfaces and second optical surfaces 14D2 made of concave curved surfaces are alternately arranged (two-dimensionally arranged) on the light exit surface side. . That is, enlarged views (enlarged cross-sectional views) of portions indicated by reference numerals G2 and G3 in FIGS. 15B and 15C have the same configurations as those described in the fourth modification. In the optical element 14E, as in the optical element 14D, the extending direction of the first optical surface 14D1 and the second optical surface 14D2 and the arrangement direction of the unit lenses 170 are inclined to each other (for example, inclined) Angle α = 45).

  Also in the illumination device and the display device using the optical element 14E having such a configuration, the same effect can be obtained by the same operation as in the above-described embodiment and the like. In the optical element 14E of the present modification, a wave structure may be formed on both the light incident surface side, the light incident surface side, and the light emitting surface side.

[Modification 6]
FIG. 16 schematically illustrates the configuration of an optical element (an optical element 14F) according to Modification 6. In the optical element 14F of this modification, a plurality of microlenses 142 are two-dimensionally arranged on the light exit surface side (P is the pitch of each microlens 142 and R is the curvature radius). That is, the optical element 14F is composed of a microlens array. Note that FIG. 16 shows an XY plane configuration of the optical element 14F and a cross-sectional configuration along the line VV in the drawing.

  Also in the illumination device and the display device using the optical element 14F having such a configuration, the same effect can be obtained by the same operation as in the above-described embodiment and the like. Also in the optical element 14F of this modification, a plurality of microlenses 142 may be formed on both the light incident surface side, the light incident surface side, and the light emitting surface side.

[Modification 7]
FIG. 17 illustrates a main configuration (part of configuration) of a lighting device according to Modification 7. The illumination device of the present modification includes a plurality of optical elements as a specific example of the “optical element” in the present disclosure, and other configurations are the same as those of the illumination device 1.

  The optical element group 14G is an optical system having a plurality of optical elements arranged along the optical axis Z0. Here, the prism array 14 and the collimator lens 14C described above are arranged along the optical axis Z0. Yes. However, the combination of a plurality of optical elements is not limited to this, and may be another combination. Specifically, for example, a combination of a prism array 14 and a lens (collimator lens 14C), a combination of a prism array 14 and a diffraction element 14B, a combination of a prism array 14 and a fly-eye lens, a diffraction element 14B and a lens (collimator). A combination with the lens 14C), a combination with the diffraction element 14B and the fly-eye lens, a combination with the lens (collimator lens 14C) and the fly-eye lens, or the like may be used. In addition to these optical elements (prism array 14, diffractive element 14B, collimator lens 14C, fly-eye lens), a plurality of optical elements including optical elements 14D, 14E, and 14F described in Modifications 4 to 6 above. Of these, two or more optical elements may be used in any combination.

  In the present modification, the driving unit 15 displaces the relative positions between the plurality of optical elements and the fly-eye lens 17 in the optical element group 14G, so that the laser beam is incident on the incident surface of the fly-eye lens 17. At least one of the incident position and the incident angle of light is changed. Specifically, the drive unit 15 displaces the relative position by causing each of the plurality of optical elements in the optical element group 14G to vibrate (microvibration) along individual directions. That is, in the example shown in FIG. 17, the drive unit 15 moves the prism array 14 along the arrangement direction (Y-axis direction) of the prisms 140 in the plane orthogonal to the optical axis Z0, as indicated by the arrow P41. It is vibrating. On the other hand, as indicated by an arrow P42, the drive unit 15 vibrates the collimator lens 14C along an in-plane direction (XY plane in-plane direction) orthogonal to the optical axis Z0.

  In the illumination device having such a configuration and a display device using the same, the same effect can be obtained by the same operation as in the above-described embodiment and the like. That is, it is possible to reduce the generation of interference patterns (improving display image quality) while reducing the size and improving the light utilization efficiency.

  Moreover, in this modification, it becomes possible to further reduce the occurrence of interference patterns by vibrating each of the plurality of optical elements in the optical element group 14G along individual directions (directions different from each other).

[Modification 8]
FIGS. 18B and 18C each show a main part configuration (partial configuration) of a lighting device according to Modification Example 8. FIG.

  In the description so far, for example, as shown in FIG. 18A, the drive unit 15 vibrates only one of the optical elements (here, the prism array 14) and the fly-eye lens 17 (optical element). Therefore, the relative position between them is displaced.

  On the other hand, in this modification, first, in the example shown in FIG. 18B, the drive unit 15 is the other of the optical elements (prism array 14) and the fly-eye lens 17 (fly-eye lens 17). By oscillating only, the relative position between them is displaced.

  In the example shown in FIG. 18C, the drive unit 15 vibrates both (both) the optical element (prism array 14) and the fly-eye lens 17, thereby displacing the relative position between them. ing.

  In this way, the drive unit 15 may oscillate at least one of the optical element and the fly-eye lens 17 to displace the relative position between them, and the same action as in the above-described embodiment and the like. Similar effects can be obtained. That is, it is possible to reduce the generation of interference patterns (improving display image quality) while reducing the size and improving the light utilization efficiency.

  In this modification, the prism array 14 is described as an example of the “optical element”. However, the present invention is not limited to this, and the diffraction element 14B, the lens (collimator lens 14C), and the optical elements 14D, 14E, and 14F described above. May be used.

[Other variations]
As described above, the technology of the present disclosure has been described with reference to the embodiment and the modifications. However, the technology is not limited to the embodiment and the like, and various modifications can be made.

  For example, in the above embodiment and the like, a prism array, a diffractive element, a lens (collimator lens), a microlens, and the like have been described as examples of the “optical element” in the present disclosure. It may be used. That is, for example, another optical element in which a plurality of unit structures are arranged one-dimensionally or two-dimensionally, or another optical element that divides an optical path of incident laser light into a plurality of periodic optical paths and emits it is used. May be. Similarly, as an “optical member” in the present disclosure, an optical member (for example, a rod integrator) other than the fly-eye lens described in the above-described embodiments and the like may be used.

  Specifically, for example, the optical element 14H shown in FIG. 19 has unevenness formed of a periodic corrugated structure (pitch: P, radius of curvature: R (+), R (−)) on the light exit surface side. Has a surface. 19A shows a YZ cross-sectional configuration and an XY plane configuration of the optical element 14H, and FIG. 19B is an enlarged view of a portion indicated by reference numeral G5 in FIG. 19A. Corresponds to the figure. Further, for example, the optical element 14I shown in FIG. 20 has a periodic diffraction structure (blazed structure, pitch: Pb, height: h) extending along the X-axis direction on the light exit surface side. ing. In addition, this periodic diffractive structure has inclined surfaces that are opposite to each other along the X-axis direction between odd-numbered rows and even-numbered rows (pitch between rows: P) along the Y-axis direction. Is formed. 20A shows the YZ cross-sectional configuration (odd and even columns) and XY plane configuration of this optical element 14I, and FIG. 20B shows the reference numerals in FIG. 20A. This corresponds to the enlarged view of the portion indicated by G6. Further, for example, the optical element 14J shown in FIG. 21 has a concavo-convex structure having a periodic inclined surface structure (pitch: Pa, inclination angle: θ) extending along the X-axis direction on the light emitting surface side. Have. In addition, this periodic concavo-convex structure is such that concave portions (valley portions) and convex portions (peak portions) are staggered between odd-numbered rows and even-numbered rows (pitch between rows: P) along the Y-axis direction. It is formed to be a position. 21A shows the YZ cross-sectional configuration (odd and even columns) and XY plane configuration of this optical element 14J, and FIG. 21B is the reference numeral in FIG. 21A. This corresponds to the enlarged view of the portion indicated by G7. Also in the optical elements 14H, 14I, and 14J having such a configuration, it is possible to obtain the same effect by the same operation as in the above-described embodiment and the like. In these optical elements 14H, 14I, and 14J, a corrugated structure, a diffractive structure, and a concavo-convex structure are formed on the light exit surface side. However, the light entrance surface side, the light entrance surface side, and the light exit surface side are formed. Both of these structures may be formed.

  In the above-described embodiment, etc., a case has been described in which a plurality of types of light sources (for red, green, and blue) are all laser light sources. However, the present invention is not limited to this case. At least one may be a laser light source. That is, a combination of a laser light source and another light source (such as an LED) may be provided in the light source unit.

  Furthermore, in the above-described embodiment and the like, the case where the light modulation element is a reflection type liquid crystal element has been described as an example. However, the present invention is not limited to this case, and may be, for example, a transmission type liquid crystal element. May be a light modulation element other than a liquid crystal element. In the above-described embodiment and the like, the case where the “optical element” in the present disclosure is a transmissive optical element (an optical element through which laser light passes) has been described as an example. However, the present invention is not limited to this case. For example, a reflective optical element (an optical element that reflects laser light) may be used.

  In addition, in the above-described embodiments and the like, the case of using three types of light sources that emit light of different wavelengths has been described. For example, instead of three types of light sources, one type, two types, or four or more types of light sources are used. You may do it.

  In the above-described embodiments and the like, each component (optical system) of the optical device and the display device has been specifically described. However, it is not necessary to include all the components, and other components are further included. You may have. Specifically, for example, instead of the dichroic prisms 131 and 132, dichroic mirrors may be provided.

  Further, in the above-described embodiment, the case where the projection optical system (projection lens) that projects the light modulated by the light modulation element on the screen is provided and configured as a projection display device has been described. Can be applied to a direct-view display device or the like.

In addition, this technique can also take the following structures.
(1)
A light source unit including a laser light source;
An optical element disposed on an optical path along which laser light from the laser light source travels;
An optical member that emits illumination light;
A drive unit that changes at least one of the incident position and the incident angle of the laser beam in the incident surface of the optical member by displacing the relative position between the optical element and the optical member. Lighting device.
(2)
The optical element is
A first optical surface that emits while converging the incident laser beam;
The illumination device according to (1), further including: a second optical surface that emits the incident laser light while diverging.
(3)
The first optical surface and the second optical surface are arranged such that the optical path of the convergent light emitted from the first optical surface and the optical path of the divergent light emitted from the second optical surface are continuously changed. The lighting device according to (2), wherein the lighting device is connected.
(4)
The lighting device according to (3), wherein the first optical surface is a convex curved surface, and the second optical surface is a concave curved surface.
(5)
The optical member is a fly-eye lens in which a plurality of unit lenses are two-dimensionally arranged.
The lighting device according to any one of (2) to (4), wherein an extending direction of the first optical surface and the second optical surface and an arrangement direction of the unit lenses are inclined with respect to each other.
(6)
The illumination device according to (1), wherein the optical element is a microlens array.
(7)
The optical element is a prism array;
In the prism array, a plurality of prisms each having a convex portion including a pair of inclined surfaces are arranged side by side along a direction orthogonal to the extending direction of the pair of inclined surfaces. Lighting equipment.
(8)
The illumination device according to (7), wherein the convex portion is provided on at least one side of an incident surface and an emission surface of each prism.
(9)
The illumination device according to (1), wherein the optical element includes one or a plurality of lenses.
(10)
The illumination device according to any one of (1) to (9), wherein the optical member is a fly-eye lens.
(11)
When the maximum value of the angle formed between the traveling direction of the light emitted from the optical element and the optical axis of the fly-eye lens is θmax, and the allowable incident angle in the fly-eye lens is θth,
The illumination device according to (10), wherein θmax ≦ θth is satisfied.
(12)
The illumination device according to any one of (1) to (11), wherein the optical element divides an optical path of incident laser light into a plurality of periodic optical paths and emits the divided optical path.
(13)
The illumination device according to any one of (1) to (12), wherein the optical element includes a plurality of unit structures arranged one-dimensionally or two-dimensionally.
(14)
The lighting device according to any one of (1) to (13), wherein the driving unit reciprocates the relative position with a driving frequency of 15 Hz or more.
(15)
The lighting device according to any one of (1) to (14), wherein the driving unit displaces the relative position by vibrating at least one of the optical element and the optical member.
(16)
A plurality of the optical elements are disposed along the optical axis,
The lighting device according to any one of (1) to (15), wherein the driving unit vibrates each of the plurality of optical elements along individual directions.
(17)
The lighting device according to any one of (1) to (16), wherein the light source unit includes three types of light sources that emit red light, green light, and blue light.
(18)
The lighting device according to (17), wherein at least one of the three types of light sources is the laser light source.
(19)
A lighting device;
A light modulation element that modulates illumination light from the illumination device based on a video signal,
The lighting device includes:
A light source unit including a laser light source;
An optical element disposed on an optical path along which laser light from the laser light source travels;
An optical member that emits the illumination light;
A display that includes: a drive unit that changes at least one of an incident position and an incident angle of a laser beam within an incident surface of the optical member by displacing a relative position between the optical element and the optical member. apparatus.
(20)
The display device according to (19), further including a projection optical system that projects the illumination light modulated by the light modulation element onto a projection surface.

DESCRIPTION OF SYMBOLS 1,1B, 1C ... Illuminating device, 11R ... Red laser, 11G ... Green laser, 11B ... Blue laser, 12R, 12G, 12B ... Lens, 131, 132 ... Dichroic prism, 14, 14A ... Prism array, 14B ... Diffraction element , 14C ... collimator lens, 14D-14F, 14H-14J ... optical element, 14G ... optical element group, 14D1 ... first optical surface (convex curved surface), 14D2 ... second optical surface (concave curved surface), 140 ... prism, 141 ... Diffraction grating, 142 ... Micro lens, 15 ... Driver, 16 ... Collimator lens, 17 ... Fly eye lens, 170 ... Unit lens, 18 ... Condenser lens, 21 ... Reflective liquid crystal element, 210 ... Illumination region, 211 ... Non-irradiation region, 22 ... polarizing beam splitter, 23 ... projection lens, 3 ... display device, 30 ... screen, 0 ... optical _{axis, S 1, S 2, S} n-1, S n ... inclined surface, Lin ... incident light, Ld ... diffracted light.

Claims (15)

A light source unit including a laser light source;
An optical element disposed on an optical path along which laser light from the laser light source travels;
A fly-eye lens that emits illumination light;
A drive unit that changes at least one of an incident position and an incident angle of a laser beam in an incident surface of the fly-eye lens by displacing a relative position between the optical element and the fly-eye lens; Prepared ,
The optical element is
A first optical surface that emits while converging the incident laser beam;
A second optical surface for emitting incident laser light while diverging;
A lighting device. The first optical surface and the second optical surface are arranged such that the optical path of the convergent light emitted from the first optical surface and the optical path of the divergent light emitted from the second optical surface are continuously changed. The lighting device according to claim 1 , wherein the lighting device is connected. Wherein the first optical surface is a convex curved surface, the second optical surface lighting device according to claim 1 or claim 2 which is concave curved. The pitch of the pitch and the second optical surface of the first optical surface, the illumination device according to any one of different claims 1 to 3 together. When the maximum value of the angle formed between the traveling direction of the light emitted from the optical element and the optical axis of the fly-eye lens is θmax, and the allowable incident angle in the fly-eye lens is θth,
Lighting device according to any one of claims 1 to 4 satisfy .theta.max ≦ [theta] th. The illumination device according to any one of claims 1 to 5 , wherein the optical element divides an optical path of incident laser light into a plurality of periodic optical paths and emits the optical path. The illumination device according to any one of claims 1 to 6 , wherein the optical element has a plurality of unit structures arranged one-dimensionally or two-dimensionally. The drive unit, by the above driving frequency 15 Hz, the lighting device according to any one of claims 1 to 7 reciprocally displacing the relative position. The drive unit is configured by vibrating at least one of the optical elements and the fly-eye lens, the illumination apparatus according to any one of claims 1 to 8 for displacing the relative positions. A plurality of the optical elements are disposed along the optical axis,
The lighting device according to any one of claims 1 to 9 , wherein the driving unit vibrates each of the plurality of optical elements along individual directions. The light source unit, an illumination apparatus according to any one of claims 1 to 1 0 having three types of light sources emitting red light, green light or blue light. Wherein at least one of the three kinds of light sources, but the lighting device according to claim 1 1 wherein a laser light source. A lighting device;
A light modulation element that modulates illumination light from the illumination device based on a video signal,
The lighting device includes:
A light source unit including a laser light source;
An optical element disposed on an optical path along which laser light from the laser light source travels;
A fly-eye lens that emits the illumination light;
A drive unit that changes at least one of an incident position and an incident angle of a laser beam in an incident surface of the fly-eye lens by displacing a relative position between the optical element and the fly-eye lens; Yes, and
The optical element is
A first optical surface that emits while converging the incident laser beam;
A second optical surface for emitting incident laser light while diverging;
A display device. The display device according to the illumination light modulated by the light modulator to claims 1 to 3, the projection optical system further comprising projecting against a projection surface. The display device according to claim 1 3 or claim 1 4 wherein the light modulation element is a liquid crystal element.

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