JP4992619B2 - Lighting device manufacturing method, lighting device and projector - Google Patents

Description

  The present invention relates to a method for manufacturing a lighting device, a lighting device and a projector, and more particularly to a technique for a method for manufacturing a lighting device that illuminates an irradiated object using diffracted light.

  In recent years, a technique using a laser light source as a light source of a projector has been proposed. Laser light sources have been developed as light sources for projectors with higher output and more colors. Compared with UHP lamps conventionally used as projector light sources, laser light sources have advantages such as high color reproducibility, instant lighting, and long life. A diffractive optical element can be used in an illumination device that uses a laser light source. The diffractive optical element can simultaneously perform shaping and enlargement of the irradiation region and equalization of the light amount distribution in the irradiation region by diffracting the laser light. By adopting a configuration that fulfills a plurality of functions by the diffractive optical element, the illumination device can be configured with a small number of parts, and the optical system can be easily downsized and space-saving. In the manufacturing process of a projector using a diffractive optical element, it is necessary to adjust the position of each element so that the diffracted light is accurately incident on the irradiation region. A technique for adjusting the optical axis using zero-order light and ± first-order diffracted light from a diffractive optical element is proposed in Patent Document 1, for example. In the technique of Patent Document 1, the positions of the diffractive optical elements are adjusted using photodetectors arranged for zero-order light and ± first-order diffracted light, respectively.

Japanese Patent Laid-Open No. 9-288249

  In the case of the projector illumination device, the irradiation area of the diffracted light (first-order diffracted light) is expanded to the size of the irradiated object. Diffracted light with an enlarged irradiation region is unsuitable for use in adjusting the position of the element. When a photodetector is used, the light reflected by the photodetector may become stray light and adversely affect image quality. For this reason, there arises a problem that it is difficult to apply the conventional technique as it is to the illumination device of the projector. The present invention has been made in view of the above-described problems, and is manufactured by a manufacturing method of an illumination device that enables diffracted light to be accurately incident on an irradiation region by simple and high-precision alignment, and the manufacturing method thereof. It is an object of the present invention to provide a lighting device and a projector using the lighting device.

  In order to solve the above-described problems and achieve the object, a manufacturing method of an illumination device according to the present invention includes a light source unit that emits light, and diffraction that emits diffracted light by diffracting light emitted from the light source unit. An illumination device that illuminates an object to be irradiated using diffracted light, the light emitted from the light source unit being incident on the diffractive optical element, and in a direction other than the direction of the irradiation region A zero-order light emission step for emitting the traveling zero-order light, and a light source unit position that adjusts the position of the light source unit so that the spot of the zero-order light coincides with the target position positioned with respect to the irradiation area of the irradiated object And an adjusting step.

  The target position and the zero-order light spot can be easily recognized visually or by a monitor. By using the target position positioned with respect to the irradiation area, it is possible to adjust the position of the light source unit with high accuracy based on the irradiation area. Thereby, the diffracted light can be accurately incident on the irradiation region by simple and highly accurate alignment.

  Moreover, as a preferable aspect of the present invention, it is desirable to include a target position setting step for setting a target position. When the target position is not set in advance on the object to be irradiated, the position of the light source unit can be adjusted by setting the target position in the target position setting step.

  As a preferred aspect of the present invention, in the light source unit position adjusting step, the zero-order light spot is made to coincide with the first target position, which is the target position, and the adjustment structure in which the second target position is set is used as the light source unit. And the adjustment structure installation step installed in the optical path between the irradiated object, the position of the zero-order light spot with respect to the first target position, and the position of the light spot from the light source unit with respect to the second target position It is desirable to include a light source unit inclination adjusting step for adjusting the inclination of the light source unit so as to cause the light source unit to adjust. By using the first target position and the second target position, it is possible to accurately adjust the inclination of the light source unit in a plane substantially parallel to the light beam from the light source unit. Thereby, the inclination adjustment of the light source part with high accuracy can be performed.

  Moreover, as a preferable aspect of the present invention, it is desirable to include an adjustment structure removing step for removing the adjustment structure. Thereby, after confirming the position of the spot of light from the light source unit with respect to the second target position, the position of the spot of zero-order light with respect to the first target position can be confirmed.

  Moreover, as a preferable aspect of the present invention, it is desirable that the adjustment structure is configured using a transparent member. Thereby, the spot position of the light from the light source unit with respect to the second target position and the position of the spot of zero-order light with respect to the first target position can be confirmed simultaneously without removing the adjustment structure.

  Moreover, as a preferable aspect of the present invention, it is desirable to include a diffractive optical element rotation angle adjusting step of adjusting the rotation angle of the diffractive optical element about an axis substantially parallel to the zero-order light beam. Thereby, it is possible to make the diffracted light enter the irradiation region more accurately.

  As a preferred embodiment of the present invention, the diffractive optical element desirably functions as an adjustment structure. Thereby, installation and removal of the structure for alignment can be made unnecessary.

  As a preferred aspect of the present invention, in the light source section tilt adjustment step, the tilt of the light source section is adjusted using a mark provided in an area other than the area where light from the light source section enters in the diffractive optical element. It is desirable. Thereby, the 2nd target position in the area | region where the light from a light source part injects among diffractive optical elements can be recognized.

  As a preferred aspect of the present invention, it is desirable that the light source unit emits a plurality of lights and emits a plurality of zero-order lights in the zero-order light emission step. Thereby, adjustment can be performed using a plurality of spots of zero-order light.

  Further, as a preferred aspect of the present invention, in the zero-order light emission step, a plurality of zero-order light beams arranged in parallel in a specific direction are emitted, and in the light source unit position adjustment step, auxiliary marks set substantially symmetrically with respect to the target position It is desirable to adjust the position of the light source unit so that a plurality of zero-order lights are incident between them. Thereby, the center position of the spot group can be easily matched with the target position.

  Moreover, as a preferable aspect of the present invention, it is desirable to include a light source unit rotation angle adjustment step of adjusting the rotation angle of the light source unit about an axis substantially parallel to the zero-order light beam. When a light source unit that emits a plurality of lights is used, the inclination of the array can be adjusted thereby. Moreover, when using the light source part which inject | emits the polarized light of a specific vibration direction, this can adjust the polarization direction of the light from a light source part.

  Furthermore, the lighting device according to the present invention is manufactured using the above-described method for manufacturing a lighting device. Thereby, the illuminating device which can make diffracted light enter into an irradiation area correctly can be obtained. Since zero-order light traveling in a direction other than the direction toward the irradiation region is not used for illumination, efficient illumination can be performed without losing illumination light.

  Furthermore, the illumination device according to the present invention includes a light source unit that emits light and a diffractive optical element that emits diffracted light by diffracting the light emitted from the light source unit, and is irradiated using the diffracted light. The object is illuminated, and the diffractive optical element emits zero-order light that travels in a direction other than the direction of the irradiated area of the irradiated object, and the zero-order light enters the target position positioned with respect to the irradiated area Features. Thereby, generation | occurrence | production of a stray light can be reduced.

  Furthermore, a projector according to the present invention includes the above-described illumination device and a spatial light modulation device that modulates light from the illumination device in accordance with an image signal. By using the illumination device described above, it is possible to make diffracted light accurately enter the irradiation region of the spatial light modulator. Thereby, a projector capable of displaying a bright and high-quality image can be obtained.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

  FIG. 1 shows a schematic configuration of a lighting device 10 manufactured by using the method for manufacturing a lighting device according to Embodiment 1 of the present invention. The illumination device 10 includes a light source unit 11 and a hologram element 12 arranged in parallel in the Z-axis direction. The light source unit 11 emits laser light in the Z-axis direction. The X axis is an axis substantially orthogonal to the Z axis. The Y axis is an axis substantially orthogonal to the Z axis and the X axis. The light source unit 11 includes, for example, a semiconductor laser. The light source unit 11 may include a semiconductor laser pumped solid state (DPSS) laser, a solid laser, a liquid laser, and a gas laser instead of the semiconductor laser.

  The hologram element 12 is a diffractive optical element that emits diffracted light by diffracting laser light emitted from the light source unit 11. As the hologram element 12, for example, a computer generated hologram (CGH) can be used. By making the light emitted from the light source unit 11 enter the hologram element 12, the hologram element 12 emits the first-order diffracted light L1 and the zero-order light L0. The hologram element 12 advances the first-order diffracted light L1 to the irradiation area AR of the irradiation object I. Further, the hologram element 12 advances the zero-order light L0 to a position other than the irradiation area AR in the irradiation object I. The zero-order light L0 is light that is not diffracted by the hologram element 12 and passes through the hologram element 12 as it is. The zero-order light L0 travels in a direction substantially parallel to the Z axis.

  FIG. 2 shows a planar configuration of the irradiation object I. The irradiated object I is, for example, a projector spatial light modulation device. The irradiation area AR is provided in a part of the surface of the irradiated object I on the side where the hologram element 12 is provided. The irradiation area AR is an area corresponding to the pixel area of the spatial light modulator. A first alignment mark M1 is formed in a region other than the irradiation region AR on the surface on which the hologram element 12 is provided. The first alignment mark M1 has a cross shape composed of two line segments that are substantially orthogonal to each other. The first alignment mark M1 is composed of a line segment substantially parallel to the X axis and a line segment substantially parallel to the Y axis.

  The irradiation area AR and the first alignment mark M1 are provided in parallel in the Y-axis direction. The position of the intersection of the first alignment marks M1 is set according to the center point of the irradiation area AR in the X-axis direction. The intersection of the first alignment marks M1 is the first target position that is positioned with respect to the irradiation area AR. For example, the first alignment mark M1 is provided around the pixel region in the spatial light modulator. In addition, the first alignment mark M1 may be provided on the periphery of the spatial light modulator, for example, on a fixing member that fixes the spatial light modulator.

  The illumination device 10 illuminates the irradiated object I using the first-order diffracted light L1 from the hologram element 12. The illumination device 10 employs an off-axis optical system that supplies illumination light in a direction other than the Z-axis direction in which the laser light emitted from the light source unit 11 travels. Thereby, it is prevented that only the portion where the first-order diffracted light L1 and the zero-order light L0 overlap in the irradiation region AR is brightened, and a uniform light amount distribution is obtained. The hologram element 12 may be any element that diffracts the laser light from the light source unit 11 and is not limited to a CGH. In addition, the hologram element 12 is not limited to diffracting light by transmitting light, but may be diffracting light by reflecting light.

  FIG. 3 illustrates adjustment for causing the first-order diffracted light L1 to be accurately incident on the irradiation area AR in the manufacturing process of the illumination device 10. The first target position is set by forming the first alignment mark M1 of the irradiation object I in the target position setting step. The relationship between the incident position of the zero-order light L 0 and the incident position of the first-order diffracted light L 1 in the irradiation object I is determined in advance by the configuration of the hologram element 12. The position of the first alignment mark M1 can be set based on the configuration of the hologram element 12 and the position of the irradiation area AR. Thus, the first alignment mark M1 is positioned with respect to the irradiation area AR. When the first alignment mark M1 is not formed in advance on the irradiation object I, the position of the light source unit 11 can be adjusted in the manufacturing process of the illumination device 10 by setting the first target position in the target position setting process. . In addition, the manufacturing method which concerns on this invention is not restricted to the case where a target position setting process is included. The first target position may be set in advance by forming the first alignment mark M1 in a process other than the manufacturing process of the illumination device 10, for example, a manufacturing process of the irradiation object I. The adjustment structure 13 is installed in the optical path between the light source unit 11 and the hologram element 12 in the adjustment structure installation process.

  FIG. 4 shows a planar configuration of the adjustment structure 13. The adjustment structure 13 is configured using, for example, a transparent member. A second alignment mark M2 is formed on the surface of the adjustment structure 13 on which light from the light source unit 11 is incident. Similar to the first alignment mark M1, the second alignment mark M2 has a cross shape composed of two line segments that are substantially orthogonal to each other. The intersection of the second alignment marks M2 is the second target position.

  FIG. 5 illustrates an adjustment procedure using the first alignment mark M1 and the second alignment mark M2. The light source unit 11 is arranged in a state where the position in the XY direction, the inclination in the YZ plane, and the inclination in the XZ plane can be adjusted. The hologram element 12 is positioned with respect to the irradiation object I using a normal mechanical means. The hologram element 12 is arranged in a state in which the rotation angle around the Z axis can be adjusted.

  The light emitted from the light source unit 11 passes through the adjustment structure 13 and then enters the hologram element 12. On the adjustment structure 13, a second spot SP2 of light from the light source unit 11 is formed. The hologram element 12 emits the first-order diffracted light L1 traveling in the direction of the irradiation area AR and simultaneously emits the zero-order light L0 traveling in a direction other than the direction of the irradiation area AR (zero-order light emission step). The zero-order light L0 travels in a direction substantially parallel to the Z axis. A first spot SP1 of zero-order light L0 is formed in a region other than the irradiation region AR in the irradiation object I.

  For example, it is assumed that the position of the first spot SP1 with respect to the intersection of the first alignment marks M1 and the position of the second spot SP2 with respect to the intersection of the second alignment marks M2 are different in the Y-axis direction. As shown in the drawing, the first spot SP1 is at a position shifted downward from the intersection of the first alignment marks M1. The second spot SP2 is at a position shifted upward from the intersection of the second alignment marks M2. For this, as shown in FIG. 6, the inclination of the light source unit 11 is changed in the YZ plane. By adjusting the inclination of the light source unit 11 in the YZ plane, the position of the first spot SP1 with respect to the first alignment mark M1 and the position of the second spot SP2 with respect to the second alignment mark M2 are matched in the Y-axis direction. .

  Thus, the inclination of the light source unit 11 is adjusted in the light source unit inclination adjustment step so that the position of the first spot SP1 with respect to the first alignment mark M1 and the position of the second spot SP2 with respect to the second alignment mark M2 are matched. . By using the adjustment structure 13 configured using a transparent member, the position of the second spot SP2 with respect to the second alignment mark M2 and the first alignment mark M1 with respect to the first alignment mark M1 without removing the adjustment structure 13. The position of one spot SP1 can be confirmed at the same time.

  Next, the light source unit 11 is moved in the Y-axis direction. By moving the light source unit 11, the first spot SP1 is made to coincide with the intersection of the first alignment marks M1. In the light source unit position adjustment step, the position of the light source unit 11 is adjusted so that the first spot SP1 coincides with the intersection of the first alignment marks M1. Due to the movement of the light source unit 11, the second spot SP2 coincides with the intersection of the second alignment marks M2. In the light source unit position adjustment step, the adjustment structure 13 may be removed. The tilt adjustment and the position adjustment of the light source unit 11 are performed while viewing the first alignment mark M1, the first spot SP1, the second alignment mark M2, and the second spot SP2 by visual observation or monitoring. By using the monitor, it is possible to avoid problems that cause discomfort to the eyes due to high-power laser light.

  Next, the rotation angle of the hologram element 12 around the Z axis is adjusted by the diffractive optical element rotation angle adjustment step. By making the first-order diffracted light L1 coincide with the irradiation area AR of the irradiation object I, the rotation angle of the hologram element 12 is adjusted. Thus, the position adjustment of the light source unit 11 and the hologram element 12 is completed. Furthermore, after the adjustment structure 13 is removed, the manufacture of the lighting device 10 shown in FIG. 1 is completed. During the driving of the illumination device 10, the zero-order light L 0 from the hologram element 12 enters the target position of the irradiation object I. The generation of stray light can be reduced by providing the irradiated object I with an absorbing member that absorbs the zero-order light L0. Further, the step of adjusting the rotation angle of the diffractive optical element may be omitted by fixing the rotation angle of the hologram element 12 around the Z axis in advance by a fixing member or the like.

  For example, as shown in FIG. 7, it is assumed that the position of the first spot SP1 with respect to the intersection of the first alignment marks M1 and the position of the second spot SP2 with respect to the intersection of the second alignment marks M2 are different in the X-axis direction. . As shown in the drawing, the first spot SP1 is at a position shifted to the right from the intersection of the first alignment marks M1. The second spot SP2 is at a position shifted to the left from the intersection of the second alignment marks M2. For this, as shown in FIG. 8, the inclination of the light source unit 11 is changed in the XZ plane.

  By adjusting the inclination of the light source unit 11 in the XZ plane, the position of the first spot SP1 with respect to the first alignment mark M1 and the position of the second spot SP2 with respect to the second alignment mark M2 are matched in the X-axis direction. . Next, the light source unit 11 is moved in the X-axis direction. By moving the light source unit 11, the first spot SP1 is made to coincide with the intersection of the first alignment marks M1. The second spot SP2 coincides with the intersection of the second alignment marks M2. In this way, the tilt adjustment and position adjustment of the light source unit 11 can be performed. In the illumination device 10 manufactured according to the present embodiment, zero-order light is incident on a target position positioned with respect to the irradiation region.

  It is difficult to clearly identify the pixel region in the spatial light modulation device visually, and the first-order diffracted light L1 incident on the spatial light modulation device is enlarged, so that the pixel region and the first-order diffracted light L1 are visually high. Accurate adjustment is often difficult. The first alignment mark M1, the second alignment mark M2, the first spot SP1, and the second spot SP2 can be easily recognized visually or with a monitor. By using the target position positioned with respect to the irradiation area AR, highly accurate position adjustment and inclination adjustment of the light source unit 11 with reference to the irradiation area AR can be performed. Thereby, there is an effect that the diffracted light can be accurately incident on the irradiation region AR by simple and highly accurate alignment.

  You may comprise the structure 13 for adjustment using members other than a transparent member. By using the adjustment structure 13 made of a member other than the transparent member, the second spot SP2 can be more easily seen. In this case, the position of the first spot SP1 with respect to the first alignment mark M1 is confirmed by removing the position of the second spot SP2 with respect to the second alignment mark M2 by removing the adjustment structure 13 through the adjustment structure removing step. Can do. The adjustment procedure described in the present embodiment is not limited to being included in the manufacturing process of the lighting device 10. For example, it is good also as including in the adjustment in the maintenance of the illuminating device 10, and the adjustment during the drive of the illuminating device 10. Since zero-order light is used for adjustment, alignment can be performed without losing illumination light even while the illumination device 10 is being driven.

  FIG. 9 illustrates a method for manufacturing a lighting apparatus according to the second embodiment of the present invention. This embodiment is characterized by using a hologram element 21 that functions as an adjustment structure. The same parts as those in the above embodiment are denoted by the same reference numerals, and redundant description is omitted. The illumination device 20 includes a light source unit 11 and a hologram element 21 arranged in parallel in the Z-axis direction. The hologram element 21 is a diffractive optical element that emits diffracted light by diffracting laser light emitted from the light source unit 11. The hologram element 21 is positioned with respect to the irradiation object I, and the rotation angle about the Z axis is adjusted in advance.

  FIG. 10 shows a planar configuration of the hologram element 21. On the hologram element 21, four marks M3 are formed. All of the four marks M3 are provided in a region around the region 22 of the hologram element 21 where the light from the light source unit 11 is incident. Each of the marks M3 has a triangular shape. The mark M3 can be formed at the same time as a pattern for diffracting light in the hologram element 21, for example.

  A line segment connecting the vertices of the mark M3 with the vertices facing each other corresponds to the second alignment mark M2 (see FIG. 4). The second target position is a point facing the vertex of each mark M3. By using the four marks M <b> 3, it is possible to recognize the second target position in the region 22 where the light from the light source unit 11 is incident in the hologram element 21. The mark M3 is not limited to a triangular shape, and may be any shape as long as the second target position can be recognized.

  FIG. 11 illustrates an adjustment procedure using the mark M3 or the like. The adjustment method is the same as that described with reference to FIG. Here, the scaler SC1 of the monitor is used together with the four marks M3. The scaler SC1 has the same shape as the second alignment mark M2. The monitor is adjusted so that the scaler SC1 matches the position of the mark M3. By using the scaler SC1 together, the second target position can be easily recognized.

  In the case of the present embodiment, installation and removal of the structure for alignment can be eliminated. The mark M3 only needs to be provided in a region other than the region where the light from the light source unit 11 enters in the hologram element 21, and is not limited to the case where it is provided in the position described in the present embodiment. By providing the mark M3 in a region other than the region where the light from the light source unit 11 is incident, the light from the light source unit 11 can be diffracted without being blocked by the mark M3.

  FIG. 12 shows a schematic configuration of a lighting device 30 manufactured using a method for manufacturing a lighting device according to a modification of the present embodiment. The illumination device 30 includes a light source unit 31 that emits a plurality of lights arranged in parallel in the X-axis direction. The hologram element 32 advances the five first-order diffracted lights L1 to the irradiation area AR of the irradiation object I. Further, the hologram element 32 advances the five zero-order lights L0 to a position other than the irradiation area AR in the irradiation object I. Each zero-order light L0 travels in the Z-axis direction.

  FIG. 13 shows a planar configuration of the irradiated object I. A first alignment mark M1, a first auxiliary mark MA, and a second auxiliary mark MB are formed in a region other than the irradiation region AR on the surface on which the hologram element 32 is provided. Each of the first auxiliary mark MA and the second auxiliary mark MB is an auxiliary mark composed of a line segment substantially parallel to the Y axis. The first auxiliary mark MA and the second auxiliary mark MB are set substantially symmetrically with respect to a line segment substantially parallel to the Y axis in the first alignment mark M1. The first auxiliary mark MA indicates the left end position of the five zero-order lights L0 from the hologram element 32. The second auxiliary mark MB indicates the right end position of the five zero-order lights L0.

  FIG. 14 shows a planar configuration of the hologram element 32. In addition to the four marks M3, the hologram element 32 is further formed with two first auxiliary marks M4A and two second auxiliary marks M4B. All of the four marks M3, the two first auxiliary marks M4A, and the two second auxiliary marks M4B are provided in a region around the region 22 of the hologram element 32 where the light from the light source unit 31 is incident. The first auxiliary mark M4A and the second auxiliary mark M4B are both auxiliary marks having a triangular shape. A line segment connecting the vertices of the first auxiliary mark M4A indicates the left end positions of the five lights from the light source unit 31. The position of the vertex of the first auxiliary mark M4A corresponds to the position of the first auxiliary mark MA (see FIG. 13).

  A line segment connecting the vertices of the second auxiliary mark M4B indicates the right end positions of the five lights from the light source unit 31. The position of the vertex of the second auxiliary mark M4B corresponds to the position of the second auxiliary mark MB (see FIG. 13). In the figure, the first auxiliary mark M4A and the second auxiliary mark M4B have a triangular shape smaller than the mark M3, but may be the same size as the mark M3. The first auxiliary mark M4A and the second auxiliary mark M4B are not limited to a triangular shape, and may be any shape.

  FIG. 15 illustrates an adjustment procedure using the first auxiliary mark MA and the second auxiliary mark MB. The hologram element 32 emits five first-order diffracted lights L1 traveling in the direction of the irradiation area AR and simultaneously emits five zero-order lights L0 traveling in directions other than the direction of the irradiation area AR (zero-order light emission step). ). The five zero-order lights L0 are arranged in parallel in a specific direction. On the hologram element 32, five second spots SP2 arranged in parallel in a specific direction are formed. The scaler SC2 has the same shape as the combined shape of the first alignment mark M1, the first auxiliary mark MA, and the second auxiliary mark MB. By using the scaler SC2, it is possible to easily recognize the second target position and both end positions of the plurality of zero-order lights L0.

  For example, as shown in the figure, it is assumed that five second spots SP2 are arranged in a direction oblique to the X axis. In this case, the rotation angle of the light source unit 31 centering on the Z axis substantially parallel to the zero-order light L0 is changed, and the second spot SP2 is arranged in parallel in the X-axis direction. For example, it is assumed that the row of the second spots SP2 is tilted such that the rightmost spot SP2 is above the leftmost spot SP2 among the five second spots SP2. In response to this, the light source unit 31 is rotated so that the rightmost spot SP2 is moved downward and the leftmost spot SP2 is moved upward. In this way, the rotation angle of the light source unit 31 is adjusted by the light source unit rotation angle adjustment step so that the second spots SP2 are aligned in the X-axis direction. Thereby, the inclination of the array can be adjusted.

  Next, it is assumed that the first spot SP1 group is at a position different from the second spot SP2 group in the X-axis direction and the Y-axis direction. For the deviation of both spot groups SP1, SP2 in the X-axis direction, the inclination of the light source unit 31 is adjusted in the XZ plane. For the deviation of both spot groups SP1, SP2 in the Y-axis direction, the inclination of the light source unit 31 is adjusted in the YZ plane. Thus, the inclination of the light source unit 31 is adjusted in the light source unit inclination adjustment step so that the position of the first spot SP1 group with respect to the first target position and the position of the second spot SP2 group with respect to the second target position are matched. .

  Next, the light source unit 31 is moved in the X-axis direction and the Y-axis direction. By moving the light source unit 31, the left end of the first spot SP1 group is made to coincide with the first auxiliary mark MA, and the right end is made to coincide with the second auxiliary mark MB. Thus, in the light source unit position adjusting step, the position of the light source unit 31 is adjusted so that the five zero-order lights L0 are incident between the first auxiliary mark MA and the second auxiliary mark MB. By matching both ends of the first spot SP1 group with the first auxiliary mark MA and the second auxiliary mark MB, the center position of the first spot SP1 group can be matched with the first target position.

  Further, the left end of the second spot SP2 group is aligned with the position indicated by the first auxiliary mark M4A by the movement of the light source unit 31. The right end of the second spot SP2 group is aligned with the position indicated by the second auxiliary mark M4B. By aligning both ends of the second spot SP2 group with the position indicated by the first auxiliary mark M4A and the position indicated by the second auxiliary mark M4B, the center position of the second spot SP2 group is the second target position. Matches. The light source unit rotation angle adjustment step may be after at least one of the light source unit inclination adjustment step and the light source unit position adjustment step.

  As described above, the illumination device 30 that uses the light source unit 31 that emits a plurality of lights can also be adjusted with high accuracy so that the diffracted light is accurately incident on the irradiation region AR. Further, by using the first auxiliary marks MA and M4A, the second auxiliary marks MB and M4B, the center position of the spot group can be easily and accurately matched with the target position. The first auxiliary mark MA, M4A, the second auxiliary mark MB, M4B is the center of the spot group, for example, when an even number of lights are emitted by the light source unit or when a large number of lights are emitted by the light source unit. Useful when it is difficult to identify the location.

  The light source unit 31 is not limited to the case of emitting five lights, and may be any one that emits a plurality of lights. The light source unit 31 may emit a plurality of lights arranged in parallel in one direction, or may emit a plurality of lights arranged in two directions orthogonal to each other. For a configuration that emits a plurality of lights arranged in parallel in two directions, in addition to auxiliary marks indicating both ends of the spot group in the X-axis direction, auxiliary marks indicating both ends of the spot group in the Y-axis direction are used in combination. Also good. The adjustment according to the procedure of this modification may be applied not only when the hologram element 32 functions as an adjustment structure, but also when the adjustment structure is used separately from the hologram element as in the first embodiment.

  For example, it is desirable to efficiently supply polarized light in a specific vibration direction to the liquid crystal display device that is the irradiation object I. When the light source unit 31 that emits polarized light in a specific vibration direction is used, the light can be efficiently modulated by the liquid crystal display device by adjusting the rotation angle of the light source unit 31. For example, when adjusting the rotation angle of the light source unit 31 so that the amount of light transmitted through the polarizing plate or the like is maximized or minimized, it takes a long time to narrow down the optimum rotation angle of the light source unit 31. On the other hand, the polarization direction of the polarized light from the light source unit 31 can be easily adjusted by the light source unit rotation angle adjustment step of the present embodiment. The light source unit 31 that emits a plurality of lights is not limited to the light source unit that emits one light, and the rotation angle may be adjusted by the light source unit rotation angle adjustment process.

  FIG. 16 shows a schematic configuration of the projector according to the third embodiment of the invention. The projector 40 is a front projection type projector that supplies light to the screen 49 and observes an image by observing light reflected by the screen 49. The projector 40 includes a red (R) light illumination device 41R, a green (G) light illumination device 41G, and a blue (B) light illumination device 41B. Each of the color light illumination devices 41R, 41G, and 41B is manufactured using the manufacturing method according to the first embodiment. Each of the color light illumination devices 41R, 41G, and 41B has the same configuration as the illumination device 10 (see FIG. 1) described in the first embodiment.

  Each of the color light illumination devices 41R, 41G, and 41B includes a light source unit that emits light and a diffractive optical element that emits diffracted light by diffracting light emitted from the light source unit, and uses the diffracted light. Illuminate the irradiated object. The diffractive optical element emits zero-order light traveling in a direction other than the direction of the irradiation region of the irradiated object. The zero-order light is incident on a target position positioned with respect to the emission region.

  The R light illumination device 41R is a light device having an R light source unit 42R. The R light source unit 42R is a light source unit that emits R light. The R light hologram element 43R is a diffractive optical element that diffracts the R light emitted from the R light source 42R. The R light hologram element 43R advances the first-order diffracted light to the irradiation region of the R light spatial light modulator 44R. The spatial light modulator for R light 44R is an irradiation object of the illumination device for R light 41R. The R light spatial light modulation device 44R is a spatial light modulation device that modulates the R light from the R light illumination device 41R according to an image signal, and is a transmissive liquid crystal display device. The R light modulated by the R light spatial light modulator 44R is incident on a cross dichroic prism 45 which is a color synthesis optical system.

  The G light illuminating device 41G is an illuminating device having a G light source 42G. The G light source unit 42G is a light source unit that emits G light. The G light hologram element 43G is a diffractive optical element that diffracts the G light emitted from the G light source 42G. The G light hologram element 43G advances the first-order diffracted light to the irradiation region of the G light spatial light modulator 44G. The G light spatial light modulator 44G is an object to be irradiated by the G light illumination device 41G. The G light spatial light modulation device 44G is a spatial light modulation device that modulates the G light from the G light illumination device 41G according to an image signal, and is a transmissive liquid crystal display device. The G light modulated by the G light spatial light modulator 44G is incident on a different surface of the cross dichroic prism 45 from the surface on which the R light is incident.

  The B light illumination device 41B is a lighting device including a B light source 42B. The B light source unit 42B is a light source unit that emits B light. The B light hologram element 43B is a diffractive optical element that diffracts the B light emitted from the B light source 42B. The B light hologram element 43B advances the first-order diffracted light to the irradiation region of the B light spatial light modulator 44B. The B light spatial light modulator 44B is an object to be irradiated by the B light illumination device 41B. The B light spatial light modulation device 44B is a spatial light modulation device that modulates the B light from the B light illumination device 41B in accordance with an image signal, and is a transmissive liquid crystal display device. The B light modulated by the B light spatial light modulator 44B is incident on a surface of the cross dichroic prism 45 different from the surface on which the R light is incident and the surface on which the G light is incident. As the transmissive liquid crystal display device, for example, a high temperature polysilicon TFT liquid crystal panel (HTPS) can be used.

  The cross dichroic prism 45 has two dichroic films 46 and 47 arranged substantially orthogonal to each other. The first dichroic film 46 reflects R light and transmits G light and B light. The second dichroic film 47 reflects B light and transmits R light and G light. The cross dichroic prism 45 combines R light, G light, and B light incident from different directions, and emits the light toward the projection lens 48. The projection lens 48 projects the light combined by the cross dichroic prism 45 toward the screen 49.

  By using the color light illumination devices 41R, 41G, and 41B manufactured by the method for manufacturing the illumination device of Example 1, the diffracted light is accurately emitted to the irradiation areas of the color light spatial light modulation devices 44R, 44G, and 44B. It can be made incident. This produces an effect that a bright and high-quality image can be displayed. Each of the color light illumination devices 41R, 41G, and 41B may be manufactured using any of the manufacturing methods of the above embodiments.

  The projector is not limited to the case where a transmissive liquid crystal display device is used as the spatial light modulation device. As the spatial light modulator, a reflective liquid crystal display (Liquid Crystal On Silicon; LCOS), DMD (Digital Micromirror Device), GLV (Grating Light Valve), or the like may be used. The projector is not limited to a configuration including a spatial light modulator for each color light. The projector may be configured to modulate two or three or more color lights with one spatial light modulator. The projector may be a slide projector that uses a slide having image information. The projector may be a so-called rear projector that supplies light to one surface of the screen and observes an image by observing light emitted from the other surface of the screen.

  As described above, the method for manufacturing an illumination device according to the present invention is suitable for manufacturing an illumination device that illuminates an irradiation object using diffracted light.

The figure which shows schematic structure of the illuminating device manufactured by Example 1 of this invention. The figure which shows the planar structure of a to-be-irradiated object. The figure explaining the adjustment for making a 1st-order diffracted light enter into an irradiation area correctly. The figure which shows the planar structure of the structure for adjustment. The figure explaining the procedure of adjustment using the 1st alignment mark etc. The figure explaining adjustment of the inclination of the light source part in a YZ plane. The figure explaining the procedure of adjustment using the 1st alignment mark etc. The figure explaining adjustment of the inclination of the light source part in a XZ plane. The figure explaining the manufacturing method of the illuminating device which concerns on Example 2 of this invention. The figure which shows the planar structure of a hologram element. The figure explaining the procedure of adjustment using a mark etc. FIG. 10 is a diagram illustrating a schematic configuration of a lighting device manufactured according to a modification of the second embodiment. The figure which shows the planar structure of a to-be-irradiated object. The figure which shows the planar structure of a hologram element. The figure explaining the procedure of adjustment using the 1st auxiliary mark, the 2nd auxiliary mark, etc. FIG. 6 is a diagram illustrating a schematic configuration of a projector according to a third embodiment of the invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Illuminating device, 11 Light source part, 12 Hologram element, AR irradiation area | region, I to-be-irradiated object, M1 1st alignment mark, 13 adjustment structure, M2 2nd alignment mark, 20 illuminating device, 21 Hologram element, 22 area | region, M3 mark, 30 illumination device, 31 light source section, 32 hologram element, MA first auxiliary mark, MB second auxiliary mark, M4A first auxiliary mark, M4B second auxiliary mark, 40 projector, 41R R light illumination device, 41G Illumination device for G light, 41B illumination device for B light, 42R light source for R light, 42G light source for G light, 42B light source for B light, 43R hologram device for R light, 43G hologram device for 43G light, 43B B Hologram element for light, spatial light modulator for 44R R light, spatial light modulator for 44G G light, 44B B Spatial light modulator for light, 45 cross dichroic prism, 46 first dichroic film, 47 second dichroic film, 48 projection lens, 49 screen

Claims (10)

Manufacturing a lighting device that includes a light source unit that emits light, and a diffractive optical element that emits diffracted light by diffracting light emitted from the light source unit, and that illuminates an irradiation object using the diffracted light A method,
A zero-order light emission step of causing the light emitted from the light source unit to enter the diffractive optical element and emitting zero-order light that travels in a direction other than the direction of the irradiation region of the irradiated object;
A target position setting step for setting a first target position positioned with respect to the irradiation region;
A light source section position adjusting step of adjusting the position of the light source unit to match the zero-order light spot on the first targets position,
The inclination of the light source unit is set so that the position of the spot of the zero-order light with respect to the first target position matches the position of the spot of light from the light source unit with respect to the second target position set in the diffractive optical element. A light source unit tilt adjustment step to be adjusted;
The manufacturing method of the illuminating device characterized by including. The method of manufacturing an illumination device according to claim 1 , further comprising a diffractive optical element rotation angle adjusting step of adjusting a rotation angle of the diffractive optical element about an axis substantially parallel to the zero-order light beam. . The light source unit tilt adjustment step adjusts the tilt of the light source unit using a mark provided in a region other than a region where light from the light source unit is incident in the diffractive optical element. Item 2. A method for manufacturing a lighting device according to Item 1 . The light source unit emits a plurality of lights,
The manufacturing method of the illuminating device according to any one of claims 1 to 3 , wherein a plurality of zero-order lights are emitted in the zero-order light emission step. In the zero-order light emission step, the plurality of zero-order lights emitted in parallel in a specific direction are emitted,
The light source unit position adjusting step adjusts the position of the light source unit so that a plurality of the zero-order lights are incident between auxiliary marks set substantially symmetrically with respect to the first target position. Item 5. A method for manufacturing a lighting device according to Item 4 . According to any one of claims 1 to 5, characterized in that it comprises a light source unit rotation angle adjusting step of adjusting the rotation angle of the light source unit around the axis substantially parallel to the ray of the zero-th order beam Manufacturing method of lighting device. A light source that emits light;
A diffractive optical element that emits diffracted light by diffracting light emitted from the light source unit, and illuminates an object to be irradiated using the diffracted light,
The diffractive optical element emits zero-order light traveling in a direction other than the direction of the irradiation region of the irradiated object,
A first target position where the zero-order light is incident is positioned with respect to the irradiation region;
A lighting device, wherein a second target position where light emitted from the light source unit enters is formed with respect to the diffractive optical element . The illumination device according to claim 7 , wherein the second target position on the diffractive optical element is set by a mark provided in a region other than a region where light from the light source unit is incident. . The lighting device according to claim 7 or claim 8 ,
And a spatial light modulator that modulates light from the illumination device in accordance with an image signal. The projector according to claim 9 , wherein a target position of the zero-order light is formed in a region other than an irradiation region irradiated with light from the illumination device of the spatial light modulator.

Images