JP6922380B2 - Lighting device - Google Patents

Description

The present invention relates to a lighting device that illuminates an illuminated area.

For example, as disclosed in Patent Document 1, a lighting device including a light source and a diffractive optical element is known. In the illuminating device disclosed in Patent Document 1, the diffractive optical element diffracts the light from the light source to illuminate the illuminated area of a desired pattern.

Japanese Unexamined Patent Publication No. 2015-132707

Lighting devices are required to be further devised to provide various information in various forms. For example, in the field of lighting equipment for vehicles, it is necessary to effectively provide information related to traffic, etc. to the passengers, pedestrians, or passengers of other vehicles of each vehicle to call their attention. Further proposals for possible lighting forms are desired. Further, the lighting device is required not only to show excellent lighting performance and information providing performance, but also to perform an optical display having a good design according to the equipment used and the environment in which it is used.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a lighting device capable of lighting and light display in various forms.

The lighting device of the present invention
A lighting device that illuminates an illuminated area.
Light source and
A diffractive optical element that diffracts the light emitted from the light source, and
A shaping optical element provided between the light source and the diffractive optical element and shaping the light emitted from the light source is provided.
The shaping optical element can be moved between a collimated position that shapes the light emitted from the light source into parallel light and a non-collimated position that shapes the light emitted from the light source into non-parallel light.

The lighting device of the present invention
A lighting device that illuminates an illuminated area.
Light source and
A diffractive optical element that diffracts the light emitted from the light source, and
A shaping optical element provided between the light source and the diffractive optical element and shaping the light emitted from the light source into parallel light.
Equipped with a light diffusing element,
The light diffusing element is inserted into an optical path between the shaping optical element and the diffractive optical element, and the light from the shaping optical element is diffused and directed toward the diffractive optical element, and the light diffusing element is retracted from the insertion position. It can be moved between the retracted position.

In the lighting device of the present invention, the shaping optical element may be a cylindrical lens.

According to the present invention, it is possible to provide a lighting device that enables various forms of lighting and light display.

FIG. 1 is a diagram for explaining the first embodiment, and is a perspective view showing a lighting device. FIG. 2A is a side view showing the lighting device of FIG. FIG. 2B is a top view showing the lighting device of FIG. FIG. 3 is a diagram corresponding to FIG. 2A, and is a diagram for explaining the operation of the lighting device of FIG. FIG. 4A is a diagram for explaining the operation of the lighting device of FIG. 1, and is a perspective view showing the lighting device and the illuminated area. FIG. 4B is a diagram for explaining the operation of the lighting device of FIG. 1, and is a perspective view showing the lighting device and the illuminated area. FIG. 4C is a diagram for explaining the operation of the lighting device of FIG. 1, and is a perspective view showing the lighting device and the illuminated area. FIG. 5 is a view for explaining the second embodiment, and is a side view showing a lighting device. FIG. 6 is a diagram for explaining the operation of the lighting device of FIG. FIG. 7A is a diagram for explaining an application example of the lighting device. FIG. 7B is a diagram for explaining an application example of the lighting device. FIG. 8A is a diagram for explaining another application example of the lighting device. FIG. 8B is a diagram for explaining another application example of the lighting device. FIG. 9A is a diagram for explaining still another application example of the lighting device. FIG. 9B is a diagram for explaining still another application example of the lighting device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, the scale, aspect ratio, etc. are appropriately changed from those of the actual product and exaggerated for the convenience of illustration and comprehension.

In addition, the terms such as "parallel", "orthogonal", and "same", and the values of length and angle, etc., which specify the shape and geometric conditions and their degrees as used in the present specification, are strictly referred to. It is interpreted to include the range in which similar functions can be expected, without being bound by any meaning.

In each of the following embodiments, an example in which the lighting device 10 is provided in the vehicle 5 and is used as a device for illuminating the illuminated area Z outside the vehicle 5 will be described. It is not limited to the example described in. For example, as a lighting device mounted on a vehicle other than a vehicle (for example, a ship or an aircraft) or other equipment, the lighting device 10 according to each of the following embodiments can be adopted. When the lighting device 10 is provided in the vehicle 5, the lighting device 10 can be used as a vehicle light such as a headlight or a tail light, or can be used as a lighting device different from the vehicle light.

[First Embodiment]
1 to 4C are views for explaining the first embodiment of the present invention, of which FIG. 1 is a perspective view schematically showing the overall configuration of the lighting device 10 of the present embodiment. 2A is a side view showing the lighting device 10 of FIG. 1, and FIG. 2B is a top view showing the lighting device 10 of FIG. In particular, FIGS. 1 to 2B show the illuminating device 10 in a state where the orthopedic optical elements 31 and 32, which will be described later, are in the collimating position.

The lighting device 10 shown in FIGS. 1 to 2B includes a light source 15 that emits light and a diffractive optical element 20 that diffracts the light emitted from the light source 15. The illuminating device 10 has a shaping optical system 30 between the light source 15 and the diffractive optical element 20 along the optical path of the light emitted from the light source 15. In the illustrated example, the light emitted from the light source 15 goes to the illuminated region Z through the shaping optical system 30 and the diffractive optical element 20. Hereinafter, each component of the lighting device 10 will be described in order.

The light source 15 is a device that emits light that is a source of illumination light that illuminates the illuminated area Z. As the light source 15, various types of light sources can be used. As an example, a light source that emits coherent light, for example, a laser light source, can be used as the light source 15. The laser light emitted from the laser light source has excellent straightness and is suitable as light for illuminating the illuminated area Z with high accuracy.

The illustrated light source 15 includes a single laser light source. Therefore, in the illustrated example, the illuminated region Z is illuminated with a color corresponding to the wavelength region of the laser beam oscillated from the light source 15. The light source 15 includes a plurality of laser light sources so that the illuminated area Z can be illuminated with a desired color, and after the light emitted from each laser light source is superposed, it heads toward the shaping optical system 30 and the diffractive optical element 20. Alternatively, the light emitted from each laser light source may pass through the shaping optical system 30 and the diffractive optical element 20 provided corresponding to the laser light source, and then superposed on the illuminated region Z. .. In such an example, the plurality of laser light sources included in the light source 15 may not only emit light in different wavelength ranges but also emit light in the same wavelength range. When the light source 15 includes a laser light source that emits light in the same wavelength range, the illuminated region Z can be brightly illuminated.

The light source 15 may be configured so that its light emission can be turned on and off (that is, turned on and off) by a control device (not shown). When a plurality of light sources 15 are provided in the lighting device 10, on and off of light emission is controlled for each light source 15, and the presence or absence of light emission may be related to each other among the light sources 15. Further, instead of controlling the light emission of the light source 15, or in addition to controlling the light emission of the light source 15, a shutter may be installed between the light source 15 and the shaping optical system 30, and the opening and closing of the shutter may be controlled by the control device. ..

Next, the diffractive optical element 20 will be described. The diffractive optical element 20 is an element that exerts a diffracting action on the light emitted from the light source 15. The illustrated diffractive optical element 20 diffracts the light from the light source 15 and directs it to the illuminated region Z. Therefore, the illuminated area Z is illuminated by the diffracted light of the diffractive optical element 20.

As an example, the diffractive optical element 20 is configured as a hologram recording medium on which an interference fringe pattern is recorded. By adjusting the interference fringe pattern in various ways, it is possible to control the traveling direction of the light diffracted by the diffractive optical element 20, in other words, the traveling direction of the light diffused by the diffractive optical element 20.

The diffractive optical element 20 can be manufactured by using, for example, scattered light from an actual scattering plate as object light. More specifically, when the hologram photosensitive material which is the base of the diffractive optical element 20 is irradiated with the reference light and the object light which are coherent lights having mutual interference, the interference fringes due to the interference of these lights become the hologram photosensitive material. The diffractive optical element 20 is manufactured. As the reference light, laser light which is coherent light is used, and as the object light, for example, scattered light from an isotropic scattering plate which can be obtained at low cost is used.

By irradiating the diffractive optical element 20 with laser light so as to travel in the opposite direction in the optical path of the reference light used when the diffractive optical element 20 is manufactured, the object light used when the diffractive optical element 20 is manufactured is used. A reproduced image of the scattering plate is generated at the original arrangement position of the scattering plate. If the scattering plate that is the source of the object light used when manufacturing the diffractive optical element 20 has uniform surface scattering, the reproduced image of the scattering plate obtained by the diffractive optical element 20 also has uniform surface illumination. The region where the reproduced image of the scattering plate is generated can be defined as the illuminated region Z.

Further, the complex interference fringe pattern formed on the diffractive optical element 20 should be reproduced along with the wavelength and incident direction of the planned reproduction illumination light instead of being formed by using the actual object light and the reference light. It is possible to design using a computer based on the shape and position of the image. The diffractive optical element 20 thus obtained is also called a computer-generated hologram (CGH). For example, when the lighting device 10 is used to illuminate an illuminated area Z having a certain size on the ground or water surface, it is difficult to generate object light, and a computer composite hologram is diffracted by an optical element. It is preferable to use as 20.

Further, a Fourier transform hologram having the same diffusion angle characteristics at each point on the diffractive optical element 20 may be formed by computer synthesis. Further, an optical member such as a lens may be provided on the downstream side of the diffractive optical element 20 to adjust the shape of the illuminated region Z.

As a specific form of the diffractive optical element 20, a volumetric hologram recording medium using a photopolymer may be used, or a volumetric hologram recording medium of a type recording using a photosensitive medium containing a silver salt material may be used. A relief type (embossed type) hologram recording medium may be used. Further, the diffractive optical element 20 may be a transmission type diffractive optical element or a reflective diffractive optical element. In this embodiment, an example in which the diffractive optical element 20 is a transmission type diffractive optical element is shown.

Next, the shaping optical system 30 will be described. The shaping optical system 30 shapes the laser beam emitted from the light source 15. In other words, the shaping optical system 30 shapes the shape of the cross section orthogonal to the optical axis of the laser beam and the three-dimensional shape of the luminous flux of the laser beam. Here, the "optical axis" is a direction along an optical path that follows the center of a region through which a target light or a luminous flux passes. In the example shown in FIGS. 1 to 2B, the shaping optical system 30 shapes the laser beam emitted from the laser light source into a widened parallel light beam. In the illustrated example, the shaping optical system 30 has a lens 35, a first shaping optical element 31, and a second shaping optical element 32 in the order along the optical path of the laser light emitted from the light source 15. The lens 35 is a lens that shapes the laser beam emitted from the light source 15 into a divergent luminous flux.

The shaping optical elements 31 and 32 are optical elements that collimate the divergent light flux generated by the lens 35 into a parallel light flux. The orthopedic optical elements 31 and 32 are all composed of a cylindrical lens, particularly a cylindrical convex lens. In the illustrated example, the first shaping optical element 31 is in a first direction (horizontal direction in the illustrated example) d1 that is orthogonal to the optical axis of the light emitted from the light source 15 and shaped into a divergent light beam by the lens 35. Shape the shape of the light. Further, the second shaping optical element 32 shapes the shape of the light in the optical axis of the light shaped by the first shaping optical element 31 and the second direction d2 orthogonal to the first direction d1.

In the example shown in FIGS. 1 to 2B, the first shaping optical element 31 and the second shaping optical element 32 are both arranged at collimating positions for shaping the light emitted from the light source 15 into parallel light. In this case, the first shaping optical element 31 shapes the shape of the light emitted from the light source 15 and shaped into the divergent light by the lens 35 into parallel light, and the second shaping optical element 32 is the first. The shape of the light shaped by the shaping optical element 31 in the second direction d2 is shaped into parallel light. As a result, the light emitted from the light source 15 and shaped into a divergent light beam by the lens 35 is collimated in both the first direction d1 and the second direction d2 and directed to the diffractive optical element 20. Therefore, when the shaping optical elements 31 and 32 are in the collimating position, the shaping optical elements 31 and 32 are parallel in shape in at least one of the first direction d1 and the second direction d2 of the light emitted from the light source 15. It means that it is in a position where it can be shaped into light. Specifically, when the divergence point of the light created by the lens 35 is located at the focal point of the shaping optical elements 31 and 32, the shaping optical elements 31 and 32 are at the collimating position.

In the lighting device 10 of the present embodiment, at least one of the first shaping optical element 31 and the second shaping optical element 32 has a collimating position for shaping the light emitted from the light source 15 into parallel light and a collimating position for shaping the light emitted from the light source 15. It is configured to be movable between a non-collimating position that shapes it into non-parallel light. Preferably, both the first shaping optical element 31 and the second shaping optical element 32 are configured to be movable between the collimated position and the non-collimated position, respectively. More preferably, the first shaping optical element 31 and the second shaping optical element 32 are configured to be independently movable between the collimated position and the non-collimated position. The fact that the shaping optical elements 31 and 32 are in the non-collimated position means that the shaping optical elements 31 and 32 are in the position where the light emitted from the light source 15 is shaped into the non-parallel light. In other words, the fact that the shaping optical elements 31 and 32 are in the non-collimating position means that the shaping optical elements 31 and 32 are in any of the first direction d1 and the second direction d2 of the light emitted from the light source 15. It also means that the shape is in a position where it does not become parallel light. Specifically, when the divergence point of the light created by the lens 35 is not located at the focal point of the shaping optical elements 31 and 32, the shaping optical elements 31 and 32 are in the non-collimating position.

The movement of the shaping optical elements 31 and 32 between the collimated position and the non-collimated position can be controlled by a control device (not shown). The orthopedic optical elements 31 and 32 are positioned alternately at one of the collimated position and the predetermined non-collimated position, that is, stopped only at either the collimated position and the predetermined non-collimated position. It may be controlled. Further, the shaping optical elements 31 and 32 may be controlled so as to stop at a collimating position, a predetermined non-collimating position, or an arbitrary position between the collimating position and the predetermined non-collimating position.

Next, the operation and operation of the lighting device 10 of the present embodiment having the configuration described above will be described. FIG. 3 is a diagram corresponding to FIG. 2A and is a diagram for explaining the operation of the lighting device 10, and FIGS. 4A to 4C are diagrams for explaining the operation of the lighting device 10. It is a perspective view which shows the lighting apparatus 10 and the illuminated area Z.

The light (laser light) emitted from the light source 15 is incident on the shaping optical system 30. Specifically, the light emitted from the light source 15 is incident on the lens 35 of the shaping optical system 30. The lens 35 diverges the light emitted from the light source 15 and shapes it into a divergent luminous flux. The light emitted from the lens 35 enters the first shaping optical element 31. When the first shaping optical element 31 is arranged at the collimating position, as shown in FIGS. 1 and 2B, the first shaping optical element 31 is the first type of light shaped into a divergent light beam by the lens 35. The shape in the direction d1 is shaped into parallel light. The light emitted from the first shaping optical element 31 is incident on the second shaping optical element 32. When the second shaping optical element 32 is arranged at the collimating position, as shown in FIGS. 1 and 2A, the second shaping optical element 32 is the first of the light shaped by the first shaping optical element 31. The shape in the two directions d2 is shaped into parallel light. The light emitted from the second shaping optical element 32, that is, the light emitted from the shaping optical system 30, is collimated in both the first direction d1 and the second direction d2, and is incident on the diffractive optical element 20.

The diffractive optical element 20 diffracts the light from the shaping optical system 30 (second shaping optical element 32) and directs it to the illuminated region Z. In other words, the diffracted light diffracted by the diffractive optical element 20 enters the illuminated area Z and illuminates the illuminated area Z. When both the shaping optical elements 31 and 32 are arranged at the collimating position, the light from the shaping optical system 30 is incident on the diffractive optical element 20 as parallel light. That is, the light emitted from the shaping optical system 30 has the same angle with respect to the plate surface of the diffractive optical element 20 and is incident on the diffractive optical element 20. At this time, the diffracted light diffracted by the diffractive optical element 20 is emitted from the diffractive optical element 20 as illumination light having a predetermined angle range according to the interference fringe pattern recorded on the diffractive optical element 20, and is emitted from the diffracted optical element 20 to the illuminated area. It is incident on Z. In FIG. 4A, when the shaping optical elements 31 and 32 are both arranged at the collimating positions, the illumination light emitted with a predetermined angle range is along the x direction parallel to the first direction d1. An example of incident on an illuminated region Z1 having a width W _{x1 and a width W y1} along the y direction orthogonal to the x direction is shown. The direction orthogonal to the x-direction and the y-direction is defined as the z-direction. That is, the illustrated illuminated area Z1 is an area having _{a width W x1 along the x direction and a width W y1} along the y direction. When the lighting device 10 illuminates a horizontal plane such as a road surface, that is, when the illuminated area Z (Z1) is arranged on the horizontal plane, both the x direction and the y direction are parallel to the horizontal direction. That is, when the illuminating device 10 illuminates a horizontal plane such as a road surface, the y direction coincides with a direction orthogonal to the x direction and parallel to the horizontal direction.

In FIG. 3, as an example in which the shaping optical element is moved to the non-collimating position, the second shaping optical element 32 is moved to the light source 15 side (first shaping optical element 31 side) by a predetermined distance, whereby the second shaping optical element 32 is moved. An example is shown in which the orthopedic optical element 32 is arranged in a non-collimated position. In FIG. 3, the second shaping optical element 32 when arranged at the collimating position is shown by a broken line, and a part of the optical path of the light from the second shaping optical element 32 to the diffractive optical element 20 in this case is indicated by an arrow. It is indicated by a dashed line with.

In the example shown in FIG. 3, when the second shaping optical element 32 is moved to the light source 15 side by a predetermined distance, the focus on the light source 15 side of the second shaping optical element 32 is the light produced by the lens 35. The light source 15 is displaced from the divergence point of the light source 15 with respect to the divergence point of the light created by the lens 35. Therefore, the light emitted from the first shaping optical element 31 is shaped into a shape in which the shape in the second direction d2 of the second shaping optical element 32 is diffused as the distance from the second shaping optical element 32 is increased, and the second shaping is performed. It emits light from the optical element 32 toward the diffractive optical element 20. In this case, the light emitted from the shaping optical system 30 (second shaping optical element 32) is diffracted as light having a certain angle range in the second direction d2 with respect to the plate surface of the diffractive optical element 20. It is incident on the element 20. Here, in the diffractive optical element 20, the light incident on the diffractive optical element 20 is diffracted by the diffractive optical element 20, and the diffractive optical element 20 has an angle corresponding to the incident angle of the light on the diffractive optical element 20. Emit from. Therefore, the light incident on the diffractive optical element 20 as non-parallel light having a certain angle range in the second direction d2 has an angle range expanded in the second direction d2 according to the angle range. It is emitted from the diffractive optical element 20. That is, when the second shaping optical element 32 is arranged at the collimating position, the second shaping optical element 32 is non-collimated as compared with the angle range of the diffracted light emitted from the diffracting optical element 20 in the second direction d2. When arranged at the position, the angular range of the diffracted light emitted from the diffractive optical element 20 in the second direction d2 becomes wide. As a result, as shown in FIG. 4B, when the second shaping optical element 32 is arranged at the non-collimating position, the width W _y2 along the y direction of the illuminated region Z2 becomes the second shaping optical. When the element 32 is arranged at the collimating position, it becomes larger than _{the width W y1 along the y direction of the illuminated area Z1.}

In this way, the diffractive optical element 20 is moved from the collimated position to the non-collimated position by moving the second shaping optical element 32 that shapes the light emitted from the light source 15 toward the diffractive optical element 20 in the second direction d2. is emitted from a larger emission angle range in the second direction d2 of the illumination light illuminating the illuminated area Z, it is possible to increase the width W _y2 in the illuminated area Z2 accordingly.

In the above description, an example in which the second shaping optical element 32 is moved to the light source 15 side by a predetermined distance and the second shaping optical element 32 is arranged at the non-colymating position has been described, but the present invention is not limited to this. The second shaping optical element 32 may be moved to the side opposite to the light source 15 (diffraction optical element 20 side) by a predetermined distance, whereby the second shaping optical element 32 may be arranged at the non-collimating position. In this case, the focal point of the second shaping optical element 32 on the light source 15 side is shifted to the side opposite to the light source 15 from the light divergence point created by the lens 35. Therefore, the light emitted from the first shaping optical element 31 is shaped into a shape in which the shape in the second direction d2 of the second shaping optical element 32 is reduced as the distance from the second shaping optical element 32 is increased, and the second shaping is performed. It emits light from the optical element 32 toward the diffractive optical element 20. In this case, the light emitted from the shaping optical system 30 (second shaping optical element 32) is diffracted as light having a certain angle range in the second direction d2 with respect to the plate surface of the diffractive optical element 20. It is incident on the element 20. Therefore, as shown in FIG. 4B, when the second shaping optical element 32 is arranged at the non-collimating position on the opposite side of the light source 15, the width W _y2 along the y direction of the illuminated region Z2 is the first. 2 When the shaping optical element 32 is arranged at the collimating position, it becomes larger than _{the width W y1 along the y direction of the illuminated area Z1.}

In the lighting device 10 described above, the light source 15 is turned off while the second shaping optical element 32 is in the collimated position, the second shaping optical element 32 is moved from the collimated position to the non-colimated position, and then the light source 15 is turned on. Then, it becomes possible to visually _{recognize the} width of the illuminated area Z along the y direction _{so as to switch from the relatively small width W y1} to the relatively large width W y2. On the contrary, when the light source 15 is turned off while the second shaping optical element 32 is in the non-collimated position, the second shaping optical element 32 is moved from the non-collimated position to the collimated position, and then the light source 15 is turned on, the illuminated area is illuminated. A display that is visually _{recognized as switching from a width W y2} having a relatively large width along the y direction of Z to a _{width W y1 having a} relatively small width becomes possible. Further, even if the second shaping optical element 32 is moved from the collimated position to the non-collimated position at a relatively high speed while the light source 15 is lit, the same display can be obtained.

Further, when the second shaping optical element 32 is moved from the collimated position to the non-collimated position at a relatively slow speed while the light source 15 is lit, the width W _{y1 in which the width of the illuminated area Z along the y direction is relatively small.} It is possible to display the image so as to continuously expand from the width to a relatively large width _Wy2. On the contrary, when the second shaping optical element 32 is moved from the non-collimated position to the collimated position while the light source 15 is lit, the width of the illuminated area Z along the y direction is relatively large from the width W _y2. It enables a display that is visually recognized so as to be continuously reduced to a small width W _y1.

Similarly, the first shaping optical element 31 that shapes the light emitted from the light source 15 and directed to the diffractive optical element 20 in the first direction d1 is moved from the collimating position to the light source 15 side or the light source 15 with respect to the collimating position. When the first shaping optical element 31 is moved to the non-collimating position separated by a predetermined distance to the side, as shown in FIG. 4C, the x of the illuminated area Z3 when the first shaping optical element 31 is arranged at the non-collimating position. The width W _x2 along the direction is larger than _{the width W x1} along the x direction of the illuminated area Z1 when the first shaping optical element 31 is arranged at the collimating position.

In this case, when the light source 15 is turned off while the first shaping optical element 31 is in the collimated position, the first shaping optical element 31 is moved from the collimated position to the non-collimated position, and then the light source 15 is turned on, the illuminated area Z A display that can be visually recognized as switching _{from a width W x1} having a relatively small width along the x direction to a width _{W x2 having a} relatively large width becomes possible. On the contrary, when the light source 15 is turned off while the first shaping optical element 31 is in the non-collimated position, the first shaping optical element 31 is moved from the non-collimated position to the collimated position, and then the light source 15 is turned on, the illuminated area is illuminated. A display that can be visually recognized as switching _{from a width W x2} having a relatively large width along the x direction of Z to a _{width W x1 having a} relatively small width becomes possible. Further, even if the first shaping optical element 31 is moved from the collimated position to the non-collimated position at a relatively high speed while the light source 15 is lit, the same display can be obtained.

Further, when the first shaping optical element 31 is moved from the collimated position to the non-collimated position at a relatively slow speed while the light source 15 is lit, the width W _{x1 in which the width of the illuminated area Z along the x direction is relatively small.} It is possible to display the image so as to continuously expand from the width W _{x 2 to a relatively large width.} On the contrary, when the first shaping optical element 31 is moved from the non-collimated position to the collimated position while the light source 15 is lit, the width of the illuminated area Z along the x direction is relatively large from the width W _x2. It enables a display that is visually recognized so as to be continuously reduced to a small width W _{x 1.}

Therefore, by making the second shaping optical element 32 of the illuminating device 10 movable between the collimated position and the non-collimated position, a new display form of the illuminated area Z illuminated by the illuminating device 10 is provided. can do.

In the examples shown in FIGS. 4A to 4C, the illuminated area Z is shown as a rectangular area, but the present invention is not limited to this, and the illuminated area Z can have an arbitrary shape. For example, the illuminated area Z can be formed so that various figures, pictures, photographs, patterns, characters, symbols, etc., or any combination thereof can be visually recognized by the observer. When the lighting device 10 is provided in the vehicle 5, the observer who visually recognizes the illuminated area Z may be a occupant in the vehicle 5, or a occupant in another vehicle, a pedestrian, or the like outside the vehicle 5. It may be a person of.

The illumination device 10 of the present embodiment is an illumination device 10 that illuminates the illuminated area Z, and includes a light source 15, a diffractive optical element 20 that diffracts the light emitted from the light source 15, and a light source 15 and a diffractive optical element 20. The shaping optical elements 31 and 32 provided between the two, and shaping the light emitted from the light source 15, are provided, and the shaping optical elements 31 and 32 have a collimating position for shaping the light emitted from the light source 15 into parallel light. It is movable between a non-collimating position that shapes the light emitted from the light source 15 into non-parallel light.

According to such an illuminating device 10, the illuminated region Z illuminated by the illuminating device 10 by making the second shaping optical element 32 of the illuminating device 10 movable between the collimated position and the non-colimated position. , A new display form can be provided.

In the lighting device 10 of the present embodiment, the shaping optical elements 31 and 32 are cylindrical lenses.

According to such a lighting device 10, the shaping optical elements 31 and 32 can be configured in a simple manner, and the overall configuration of the lighting device 10 can be simplified and reduced in weight. Further, this makes it possible to reduce the cost of the lighting device 10.

[Second Embodiment]
Next, the second embodiment will be described. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in the above-mentioned first embodiment shall be used for the parts that can be configured in the same manner as in the above-mentioned first embodiment. , And the duplicate description will be omitted. FIG. 5 is a view for explaining the second embodiment, is a side view showing the lighting device 10, and FIG. 6 is a view for explaining the operation of the lighting device 10 of FIG.

In the examples shown in FIGS. 5 and 6, the shaping optical system 30 has a lens 35 and a shaping optical element 37 in the order along the optical path of the laser beam emitted from the light source 15. The shaping optical element 37 is an optical element that collimates the divergent light flux generated by the lens 35 into a parallel light flux. Such a shaping optical element 37 may be composed of, for example, a convex lens. Further, the shaping optical element 37 may be composed of a cylindrical lens, particularly a combination of two cylindrical lenses such as the shaping optical elements 31 and 32 in the first embodiment described above.

The lighting device 10 shown in FIGS. 5 and 6 further includes a light diffusing element 40. The light diffusing element 40 is an optical element capable of anisotropically diffusing the light transmitted from one side to the other side of the plate surface of the light diffusing element 40. As such a light diffusing element 40, for example, it is arranged on at least one main surface of a plate-shaped member having a pair of main surfaces along one direction parallel to the plate surface, and is parallel to the plate surface and said one. Those provided with a large number of linear protrusions or recesses extending in a direction orthogonal to the direction can be used.

In the present embodiment, the light diffusing element 40 is inserted into the optical path between the shaping optical element 37 and the diffractive optical element 20, and the insertion position where the light from the shaping optical element 37 is diffused and directed toward the diffractive optical element 20 is determined. It is possible to move between the retracted position retracted from the insertion position and the retracted position. As a result, the light diffusing element 40 diffuses the light incident on the light diffusing element 40 from the shaping optical element 37 at the insertion position in any direction orthogonal to the optical axis of the light emitted from the shaping optical element 37. Therefore, it can be emitted toward the diffractive optical element 20. The movement of the light diffusing element 40 between the insertion position and the retracting position can be controlled by a control device (not shown).

Next, the operation and operation of the lighting device 10 of the present embodiment having the configuration described above will be described.

FIG. 5 shows the lighting device 10 in a state where the light diffusing element 40 is arranged at the retracted position. In the illustrated example, the light emitted from the light source 15 and shaped into a divergent light beam by the lens 35 is shaped into parallel light by the shaping optical element 37 and emitted from the shaping optical element 37 toward the light diffusing element 40. The light from the shaping optical system 30 (shaping optical element 37) is incident on the diffractive optical element 20 as parallel light. Therefore, as in the case where the shaping optical elements 31 and 32 are arranged at the collimating position in the first embodiment, the light incident on the diffractive optical element 20 is diffracted by the diffractive optical element 20 and becomes the first direction d1. It is incident on an illuminated region Z1 having a width W _{x1 along the parallel x direction and a width W y1} along the y direction orthogonal to the x direction (see FIG. 4A).

FIG. 6 shows the lighting device 10 in a state where the light diffusing element 40 is moved from the retracted position to the inserted position. In FIG. 6, the light diffusing element 40 when it is arranged at the retracted position is shown by a broken line. In the illustrated example, when the light diffusing element 40 is arranged at the insertion position in a direction capable of diffusing the parallel light emitted from the shaping optical element 37 in the second direction d2, the light diffusing element 40 emits light from the shaping optical element 37 and diffuses the light. The light diffused by the element 40 is incident on the diffractive optical element 20 as non-parallel light having a certain angle range in the second direction d2 with respect to the plate surface of the diffractive optical element 20. _{Therefore, the width W y2} along the y direction of the illuminated area Z2 when the light diffusing element 40 is arranged at the insertion position is the illuminated area when the light diffusing element 40 is arranged at the retracted position. _{It becomes larger than the width W y1} along the y direction of Z1 (see FIG. 4B).

Further, when the light diffusing element 40 is arranged at the insertion position in a direction capable of diffusing the parallel light emitted from the shaping optical element 37 in the first direction d1, it is emitted from the shaping optical element 37 and diffused by the light diffusing element 40. The generated light is incident on the diffractive optical element 20 as non-parallel light having a certain angle range in the first direction d1 with respect to the plate surface of the diffractive optical element 20. _{Therefore, the width W x2} along the x direction of the illuminated area Z3 when the light diffusing element 40 is arranged at the insertion position is the illuminated area when the light diffusing element 40 is arranged at the retracted position. _{It becomes larger than the width W x1} along the x direction of Z1 (see FIG. 4C).

Therefore, also in the present embodiment, the lighting device 10 has the light diffusing element 40 that can move between the insertion position and the retracted position, so that the lighting device 10 is illuminated in the same manner as in the first embodiment described above. It is possible to provide a new display form of the illuminated area Z illuminated by the device 10.

The illumination device 10 of the present embodiment is an illumination device 10 that illuminates the illuminated area Z, and includes a light source 15, a diffractive optical element 20 that diffracts the light emitted from the light source 15, and a light source 15 and a diffractive optical element 20. The light diffusing element 40 includes a shaping optical element 37 and a light diffusing element 40, which are provided between the two and shape the light emitted from the light source 15 into parallel light. It is movable between an insertion position where the light is inserted into the optical path between them and diffuses the light from the shaping optical element 37 toward the diffractive optical element 20 and a retracted position retracted from the insertion position.

According to such a lighting device 10, a new illuminated area Z illuminated by the lighting device 10 is provided by having the light diffusing element 40 that can move between the insertion position and the retracting position. A display form can be provided.

An application example of the lighting device 10 of the present invention will be described with reference to FIGS. 7A to 9B.

7A and 7B are diagrams for explaining an application example of the lighting device 10. In the illustrated example, the lighting device 10 constitutes the headlight of the vehicle 5. Therefore, the lighting devices 10 are arranged on the left and right sides of the front surface of the vehicle 5, respectively. When the shaping optical elements 31 and 32 are arranged at the collimating position, or when the light diffusing element 40 is arranged at the retracted position, the illuminated area Z is the illuminated area Z1 described with reference to FIG. 4A. Is formed by. FIG. 7A shows the illuminated area Z1 in this case. The illuminated area Z1 is formed so as to extend from each of the lighting devices 10 toward the road surface in front of the vehicle 5. The y direction of FIG. 4A coincides with the front-rear direction of the vehicle 5, the x direction coincides with the left-right direction of the vehicle 5, and the z direction coincides with the vertical direction.

In the example shown in FIG. 7A, when the second shaping optical element 32 is moved to the non-collimating position, or the light diffusing element 40 can diffuse the parallel light emitted from the shaping optical element 37 in the second direction d2. When arranged at the insertion position in the orientation, the illuminated area Z is formed by the illuminated area Z2 described with reference to FIG. 4B. As shown in FIG. 7B, the illuminated area Z2 extends from each lighting device 10 toward the road surface in front of the vehicle 5 longer than the illuminated area Z1 in the example shown in FIG. 7A. This makes it possible to illuminate the road surface in front of the vehicle 5 farther than the illuminated area Z1 shown in FIG. 7A.

8A and 8B are diagrams for explaining another application example of the lighting device 10. In the illustrated example, the lighting device 10 is provided at the rear of the vehicle 5, and the illuminated area Z is formed on the road surface behind the vehicle 5. When the shaping optical elements 31 and 32 are arranged at the collimating position, or when the light diffusing element 40 is arranged at the retracted position, the illuminated area Z is the illuminated area Z1 described with reference to FIG. 4A. Is formed by. FIG. 8A shows the illuminated area Z1 in this case. The y direction of FIG. 4A coincides with the front-rear direction of the vehicle 5, the x direction coincides with the left-right direction of the vehicle 5, and the z direction coincides with the vertical direction.

In the example shown in FIG. 8A, when the first shaping optical element 31 is moved to the non-collimating position, or the light diffusing element 40 can diffuse the parallel light emitted from the shaping optical element 37 in the first direction d1. When arranged at the insertion position in the orientation, the illuminated area Z is formed by the illuminated area Z3 described with reference to FIG. 4C. As shown in FIG. 8B, the illuminated area Z3 forms the illuminated area Z3 behind the vehicle 5 so that a strip-shaped figure extending in the left-right direction (width direction) of the vehicle 5 can be visually recognized on the road surface. be able to.

As an example, when the vehicle 5 is stopped due to waiting for a traffic light or the like, by forming such an illuminated area Z on the road surface behind the vehicle 5, an appropriate inter-vehicle distance is provided for the vehicle located behind the vehicle 5. It is possible to show a guideline for the stop position where the distance can be maintained. It is also effective to include a message such as "STOP" in the illuminated area Z. Such a display attracts the eyes of the driver of the vehicle behind. Therefore, the occurrence of rear-end collisions can be suppressed, which can contribute to traffic safety.

9A and 9B are diagrams for explaining still another application example of the lighting device 10. In the illustrated example, the lighting device 10 is provided in the front part of the vehicle 5, and the illuminated area Z is formed on the road surface in front of the vehicle 5. When the shaping optical elements 31 and 32 are arranged at the collimating position, or when the light diffusing element 40 is arranged at the retracted position, the illuminated area Z is the illuminated area Z1 described with reference to FIG. 4A. Is formed by. FIG. 9A shows the illuminated area Z1 in this case. The y direction of FIG. 4A coincides with the front-rear direction of the vehicle 5, the x direction coincides with the left-right direction of the vehicle 5, and the z direction coincides with the vertical direction.

In the example shown in FIG. 9A, when the first shaping optical element 31 is moved to the non-collimating position, or the light diffusing element 40 can diffuse the parallel light emitted from the shaping optical element 37 in the first direction d1. When arranged at the insertion position in the orientation, the illuminated area Z is formed by the illuminated area Z3 described with reference to FIG. 4C. As shown in FIG. 9B, the illuminated area Z3 forms the illuminated area Z3 in front of the vehicle 5 so that a band-shaped figure extending in the left-right direction (width direction) of the vehicle 5 can be visually recognized on the road surface. be able to.

As an example, when the vehicle 5 is traveling, for example, during deceleration for stopping, by forming such an illuminated region Z on the road surface in front of the vehicle 5, the braking distance according to the speed of the vehicle 5 is increased. Can give a guide. In this case, when the illuminated region Z is formed on the road surface in front of the vehicle traveling in front of the vehicle 5, an appropriate inter-vehicle distance is maintained between the vehicle 5 and the vehicle traveling in front. It can be judged that there is. As a result, the driver of the vehicle 5 can control the vehicle speed according to the formation position of the illuminated region Z. Therefore, even in this case, the occurrence of a rear-end collision can be suppressed, which can contribute to traffic safety.

Further, as another example, the vehicle stops in front of a pedestrian or the like who is about to cross the road on which the vehicle 5 is traveling, and such an illuminated area Z is formed on the road surface in front of the vehicle 5 by the driver's operation. By forming it, it is possible to display to the pedestrian or the like that he / she is willing to cross the road. It is also effective to include a message such as "please go ahead" in the illuminated area Z. As a result, the driver of the vehicle 5 does not have to show the intention to cross the road to the pedestrian or the like by gesturing, and the driver of the vehicle 5 quickly communicates with the pedestrian or the like. Becomes possible. Therefore, it is possible to reduce the time required for crossing a pedestrian or the like, thereby suppressing the occurrence of traffic congestion due to the crossing of a pedestrian or the like.

In each of the above-mentioned application examples, for example, by moving the first shaping optical element 31 from the collimated position to the non-colimated position at a relatively slow speed while the light source 15 is lit, the illuminated region Z is moved along the x direction or the y direction. It is possible to display such that the _{width W x1} or W _y1 having a relatively small width _{is continuously expanded to a width W x2} or W _{y2 having a} relatively large width. Further, by moving the first shaping optical element 31 from the non-collimated position to the collimated position at a relatively slow speed while the light source 15 is lit, the width of the illuminated area Z along the x direction or the y direction is relatively large. A display that continuously expands from a large width W _x2 or _Wy2 to a relatively small width W _x1 or _{Wy1 can be displayed.} Such a display of the illuminated area Z has not existed in the past and is novel. In particular, in the application example described with reference to FIGS. 8A to 9B, the illuminated area Z is displayed so as to suddenly appear on the road surface behind or in front of the vehicle 5 so as to spread to the left and right in an empty place. It is also possible to display with high design.

5 Vehicle 10 Lighting device 15 Light source 20 Diffraction optical element 30 Orthopedic optical system 31 First orthopedic optical element 32 Second orthopedic optical element 35 Lens 37 Orthopedic optical element 40 Light diffusing element Z, Z1, Z2, Z3 Illuminated area

Claims (3)

A lighting device that illuminates an illuminated area.
Light source and
A diffractive optical element that diffracts the light emitted from the light source, and
A shaping optical element provided between the light source and the diffractive optical element and shaping the light emitted from the light source is provided.
Said shaping optical element is a collimating position to shape the light emitted from the light source into parallel light, and a non-collimated position to shape the light emitted from the light source to the non-parallel light, Ri movable der between,
When the shaping optical element is arranged at the collimating position, the light emitted from the light source and passing through the shaping optical element is incident on the diffractive optical element as parallel light . A lighting device that illuminates an illuminated area.
Light source and
A diffractive optical element that diffracts the light emitted from the light source, and
A shaping optical element provided between the light source and the diffractive optical element and shaping the light emitted from the light source into parallel light.
Equipped with a light diffusing element,
The light diffusing element is inserted into an optical path between the shaping optical element and the diffractive optical element, and the light from the shaping optical element is diffused and directed toward the diffractive optical element, and the light diffusing element is retracted from the insertion position. and the retracted position, Ri movable der between,
When the light diffusing element is arranged at the retracted position, the light emitted from the light source and passing through the shaping optical element is incident on the diffractive optical element as parallel light . The lighting device according to claim 1 or 2, wherein the shaping optical element is a cylindrical lens.

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