JP5429475B2 - Lighting device and projector - Google Patents

Description

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

  In recent years, a projector using an illumination device having a solid light source such as a semiconductor laser, a super luminescent diode (SLD), or a light emitting diode (LED) has been developed or commercialized. The solid light source is small and light, and the light emission luminance has been remarkably improved by recent developments. For example, Patent Document 1 describes a configuration in which a plurality of semiconductor lasers are arranged in a two-dimensional array as a light source of an illumination device. Thereby, high output of the lighting device is realized.

  However, in an illuminating device in which a plurality of semiconductor lasers are arranged, there is a problem that uneven illumination occurs in the illuminated area because the light source is only a set of point light sources even if the illuminated area is uniformly illuminated. For example, in Patent Document 2, in an illumination device having a plurality of laser light sources, the intensity pattern of light superimposed on the illuminated area is increased by shifting the incident area of each laser beam on the fly-eye lens, A technique for reducing illuminance unevenness of illumination light on an illuminated area is described.

WO99 / 49358 JP 2009-42637 A

  One of the objects according to some aspects of the present invention is to provide an illuminating device that can reduce illuminance unevenness of illumination light. Another object of some aspects of the present invention is to provide a projector having the illumination device.

The lighting device according to the present invention includes:
A light source for supplying a first light beam and a second light beam;
A first split fly-eye lens that splits the first light flux into a plurality of partial light fluxes;
A second split fly-eye lens that splits the second light flux into a plurality of partial light fluxes;
A first condensing fly-eye lens that individually collects the plurality of partial light beams divided by the first divided fly-eye lens;
A second condensing fly-eye lens that individually collects the plurality of partial light beams divided by the second divided fly-eye lens;
Light flux superimposition for superimposing the plurality of partial light fluxes collected by the first light collection fly-eye lens and the plurality of partial light fluxes collected by the second light collection fly-eye lens on an illuminated area A condenser lens,
Including
The first divided fly-eye lens and the second divided fly-eye lens are composed of rectangular element lenses having a long side and a short side,
The element lenses of the first split fly-eye lens are arranged in a plurality of rows and columns along an X axis parallel to the long side and a Y axis parallel to the short side,
The element lenses of the second divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The shape of the first incident region of the first light beam with respect to the first divided fly-eye lens and the shape of the second incident region of the second light beam with respect to the second divided fly-eye lens are long axes parallel to the X axis. And a short axis parallel to the Y-axis,
The length of the long side of the element lens is Lx,
The length of the short side of the element lens is Ly,
The major axis length Bx satisfies a relationship of 1.2 × Lx ≦ Bx ≦ 2 × Lx, and the minor axis length By satisfies a relationship of 1.2 × Ly ≦ By ≦ 2 × Ly, The length Bx of the major axis and the length By of the minor axis satisfy the relationship Bx: By = Lx: Ly,
The first incident area includes a first vertex common to the four element lenses in the first split fly-eye lens, and the center of the first light flux is separated from the first vertex by a distance D in a predetermined direction. Area,
The second incident region has a position where the center of the second light flux is separated from the second vertex common to the four element lenses in the second divided fly-eye lens by the distance D in the predetermined direction. The region is shifted by 0.5 × Lx along the X axis and 0.5 × Ly along the Y axis.

  According to such an illuminating device, the illuminance unevenness of illumination light can be reduced.

In the lighting device according to the present invention,
The light source has a first emission surface formation region and a second emission surface formation region in which a plurality of emission surfaces are arranged,
A first light beam forming condenser lens that superimposes the light emitted from the plurality of emission surfaces of the first emission surface formation region on the first divided fly-eye lens to form the first light beam;
A second light beam forming condenser lens that superimposes the light emitted from the plurality of emission surfaces of the second emission surface forming region on the second divided fly-eye lens to form the second light beam;
Can further be included.

  According to such an illuminating device, the light intensity distribution can be made uniform, and the first light flux and the second light flux with high light intensity can be formed.

In the lighting device according to the present invention,
The distance between the first light beam forming condenser lens and the first split fly-eye lens is larger than the focal length of the first light beam forming condenser lens, and the length of the major axis of the first incident region is the first distance. It is a distance that is smaller than the effective diameter of a single beam forming condenser lens,
The distance between the second light beam forming condenser lens and the second split fly-eye lens is larger than the focal length of the second light beam forming condenser lens, and the length of the major axis of the second incident region is the first distance. The distance can be smaller than the effective diameter of the two-beam forming condenser lens.

  According to such an illuminating device, the utilization efficiency of light can be improved.

In the lighting device according to the present invention,
A plurality of first collimating lenses arranged corresponding to the plurality of emission surfaces of the first emission surface forming region and individually converting light emitted from the plurality of emission surfaces into parallel light;
A plurality of first condensing lenses arranged corresponding to the first collimating lens and individually condensing the parallel light converted by the first collimating lens on the first light flux forming condenser lens;
A plurality of second collimating lenses that are arranged corresponding to the plurality of emission surfaces of the second emission surface forming region and individually convert the light emitted from the plurality of emission surfaces into parallel light;
A plurality of second condensing lenses arranged corresponding to the second collimating lenses and individually condensing the parallel light converted by the second collimating lenses on the second light flux forming condenser lens;
Further including
The first collimating lens and the first condenser lens are disposed on an optical path between the light source and the first light beam forming condenser lens,
The second collimating lens and the second condenser lens may be disposed on an optical path between the light source and the second light beam forming condenser lens.

  According to such an illuminating device, control of an incident angle of light incident on the first divided fly-eye lens and the second divided fly-eye lens by the first light flux forming condenser lens and the second light flux forming condenser lens. Can be easily performed. Thereby, the freedom degree of design can be improved.

According to the lighting device according to the present invention,
A first light is disposed on an optical path between the first light beam forming condenser lens and the first divided fly-eye lens, and condenses the light emitted from the first light beam forming lens on the first divided fly-eye lens. With field lenses,
The second light beam forming condenser lens is disposed on the optical path between the second split fly-eye lens and the light emitted from the second light beam forming lens is condensed on the second split fly-eye lens. Two field lenses,
Can further be included.

  According to such an illuminating device, the utilization efficiency of light can be improved.

The lighting device according to the present invention includes:
A light source for supplying a first light beam, a second light beam, a third light beam, and a fourth light beam;
A first split fly-eye lens that splits the first light flux into a plurality of partial light fluxes;
A second split fly-eye lens that splits the second light flux into a plurality of partial light fluxes;
A third split fly-eye lens that splits the third light flux into a plurality of partial light fluxes;
A fourth split fly-eye lens that splits the fourth light flux into a plurality of partial light fluxes;
A first condensing fly-eye lens that individually collects the plurality of partial light beams divided by the first divided fly-eye lens;
A second condensing fly-eye lens that individually collects the plurality of partial light beams divided by the second divided fly-eye lens;
A third condensing fly-eye lens that individually collects the plurality of partial light beams divided by the third divided fly-eye lens;
A fourth condensing fly-eye lens that individually collects the plurality of partial light beams divided by the fourth divided fly-eye lens;
The plurality of partial light beams collected by the first light collection fly-eye lens, the plurality of partial light beams collected by the second light collection fly-eye lens, and the third light collection fly-eye lens. A light beam superimposing condenser lens that superimposes the plurality of emitted partial light beams and the plurality of partial light beams collected by the fourth fly-eye lens on an illuminated area;
Including
The first, second, third, and fourth split fly's eye lenses are composed of rectangular element lenses having a long side and a short side,
The element lenses of the first split fly-eye lens are arranged in a plurality of rows and columns along an X axis parallel to the long side and a Y axis parallel to the short side,
The element lenses of the second divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The element lenses of the third divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The element lenses of the fourth divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The shape of the first incident region of the first light beam with respect to the first divided fly-eye lens, the shape of the second incident region of the second light beam with respect to the second divided fly-eye lens, and the first shape with respect to the third divided fly-eye lens The shape of the third incident region of the three light beams and the shape of the fourth incident region of the fourth light beam with respect to the fourth divided fly-eye lens are a long axis parallel to the X axis and a short axis parallel to the Y axis. An elliptical shape having
The length of the long side of the element lens is Lx,
The length of the short side of the element lens is Ly,
The major axis length Bx satisfies a relationship of 1.2 × Lx ≦ Bx ≦ 2 × Lx, and the minor axis length By satisfies a relationship of 1.2 × Ly ≦ By ≦ 2 × Ly, The length Bx of the major axis and the length By of the minor axis satisfy the relationship Bx: By = Lx: Ly,
The first incident region includes a first vertex that is a common vertex of the four element lenses in the first split fly-eye lens, and a center of the first light flux is a distance from the first vertex in a predetermined direction. Is a region separated by D,
The second incident region is a position where the center of the second light flux is separated from the second vertex, which is a common vertex of the four element lenses in the second divided fly-eye lens, by the distance D in the predetermined direction. From 0.5 × Lx along the X axis and 0.5 × Ly along the Y axis,
The third incident area is a position where the center of the third light flux is separated from the third vertex, which is a common vertex of the four element lenses in the third divided fly-eye lens, by the distance D in the predetermined direction. Is a region shifted by 0.5 × Lx along the X-axis,
The fourth incident area is a position where the center of the fourth light flux is separated from the fourth vertex, which is a common vertex of the four element lenses in the fourth divided fly-eye lens, by the distance D in the predetermined direction. The region is shifted by 0.5 × Ly along the Y axis.

  According to such an illuminating device, the illuminance unevenness of illumination light can be reduced.

According to the lighting device according to the present invention,
The light source may be any one of a semiconductor laser, a super luminescent diode, and a light emitting diode.

  According to such an illuminating device, the brightness of the light source can be increased.

The projector according to the present invention is
A lighting device according to the present invention;
A light modulation device that modulates light emitted from the illumination device according to image information;
A projection device for projecting an image formed by the light modulation device;
including.

  According to such a projector, since an illumination device that can reduce illuminance unevenness is used, an image with little illuminance unevenness can be projected.

The figure which shows typically the illuminating device which concerns on 1st Embodiment. The figure which shows typically the illuminating device which concerns on 1st Embodiment. The figure which shows typically a part of illuminating device which concerns on 1st Embodiment. The figure which looked at a part of 1st and 2nd division | segmentation fly eye lens from the Z-axis direction. The figure which shows typically the model used for the 1st experiment example of 1st Embodiment. The top view which shows typically the light source of the model used for the 1st experiment example of 1st Embodiment. The table | surface which shows the lens conditions of the model used for the 1st experiment example of 1st Embodiment. The distribution map which shows the result of the 1st experiment example of 1st Embodiment. The distribution map which shows the result of the 1st experiment example of 1st Embodiment. The distribution map which shows the result of the 1st experiment example of 1st Embodiment. The figure which looked at a part of 1st and 2nd division | segmentation fly eye lens from the Z-axis direction. The figure which looked at part of the division | segmentation fly eye lens of the model used for the 2nd experiment example from the Z-axis direction. The graph which shows the result of the 2nd experiment example of 1st Embodiment. The figure which shows typically the illuminating device which concerns on 2nd Embodiment. The figure which looked at a part of 1st and 2nd division | segmentation fly eye lens from the Z-axis direction. The figure which shows typically the model used for the 1st experiment example of 2nd Embodiment. The distribution map which shows the result of the 1st experiment example of 2nd Embodiment. The distribution map which shows the result of the 1st experiment example of 2nd Embodiment. The distribution map which shows the result of the 1st experiment example of 2nd Embodiment. The distribution map which shows the result of the 1st experiment example of 2nd Embodiment. The distribution map which shows the result of the 1st experiment example of 2nd Embodiment. The graph which shows the result of the 2nd experiment example of 2nd Embodiment. FIG. 10 is a diagram schematically illustrating a projector according to a third embodiment.

  Preferred embodiments of the present invention will be described below with reference to the drawings.

1. 1. First embodiment 1.1. Illumination Device According to First Embodiment First, the illumination device 100 according to the first embodiment will be described. 1 and 2 are diagrams schematically showing the lighting device 100. FIG. FIG. 3 is a partially enlarged view of FIG. In FIG. 1 to FIG. 3, the distance between lenses and the lens shape are illustrated differently for convenience. In the present embodiment, a case where the lighting device 100 is applied to a lighting device for a light source of a projector will be described.

  As shown in FIGS. 1 to 3, the illuminating device 100 includes a light source 10, a first divided fly-eye lens 60a, a second divided fly-eye lens 60b, a first condensing fly-eye lens 70a, and a second collection. An optical fly-eye lens 70b and a light beam superimposing condenser lens 80 are included. The illumination device 100 further includes a first collimator lens 20a, a second collimator lens 20b, a first condenser lens 30a, a second condenser lens 30b, a first light beam forming condenser lens 40a, and a second light beam forming unit. A condenser lens 40b, a first field lens 50a, a second field lens 50b, and a field lens 90 can be included.

  In the illuminating device 100, the 1st emitted light 1a radiate | emitted from the several output surface 14 arranged in the 1st output surface formation area | region 12a of the light source 10 is 1st collimating lens 20a, 1st condensing lens 30a, 1st. The second light exit surface forming region 12b of the light source 10 travels along the first optical path formed by the light beam forming condenser lens 40a, the first field lens 50a, the first split fly-eye lens 60a, and the first condensing fly-eye lens 70a. The second emitted light 1b emitted from the plurality of emitting surfaces 14 arranged in the second collimating lens 20b, the second condensing lens 30b, the second light flux forming condenser lens 40b, the second field lens 50b, the second splitting. The light from the first optical path travels along the second optical path formed by the fly-eye lens 60b and the second condensing fly-eye lens 70b. The luminous flux superimposing the condenser lens 80 and the light from the second optical path through a field lens 90, it is possible to form the illumination light is superimposed on the incident surface 112 of the light valve 110. Hereinafter, each member constituting the lighting device 100 will be described.

  The light source 10 can supply a first light beam 2a incident on the first divided fly-eye lens 60a and a second light beam 2b incident on the second divided fly-eye lens 60b. As the light source 10, for example, a solid-state light source such as a semiconductor laser, a super luminescent diode (SLD), or a light emitting diode (LED) can be used. Thereby, the brightness of the light source 10 can be increased. For example, as illustrated in FIG. 3, the light source 10 includes a first emission surface formation region 12 a and a second emission surface formation region 12 b in which a plurality of emission surfaces 14 are arranged. In the emission surface forming regions 12a and 12b, for example, the emission surfaces 14 can be arranged in a plurality of rows and columns. In addition, the number of the output surfaces 14 arranged in the output surface formation area | region 12a, 12b is not limited. Although not shown, the emission surface 14 can be, for example, a side surface of an active layer sandwiched between clad layers when the light source 10 uses an edge-emitting light emitting element. In the light source 10, for example, a plurality of light emitting elements (for example, SLDs) are arranged in each of the emission surface forming regions 12a and 12b on the support substrate, thereby arranging the plurality of emission surfaces 14 in the emission surface forming regions 12a and 12b. be able to. For example, the first outgoing light 1a is superimposed on the incident surface of the first split fly-eye lens 60a as the first light flux 2a by the first light flux forming condenser lens 40a. The second emitted light 1b is superimposed as the second light beam 2b on the incident surface of the second divided fly-eye lens 60b, for example, by the second light beam forming condenser lens 40b. That is, the first emission surface forming region 12a can be a region where the emission surface 14 that emits the light constituting the first light flux 2a is disposed. The second emission surface formation region 12b can be a region where the emission surface 14 that emits light constituting the second light beam 2b is disposed. The light emitted from the plurality of emission surfaces 14 is, for example, divergent light having a predetermined radiation angle.

  Although not illustrated, for example, the emitted lights 1a and 1b may be directly incident on the divided fly-eye lenses 60a and 60b. For example, the first outgoing light 1a is directly incident on the first split fly-eye lens 60a as the first light flux 2a, and the second outgoing light 1b is directly incident on the second split fly-eye lens 60b as the second light flux 2b. Also good. This eliminates the need for the optical systems 20a, 20b, 30a, 30b, 40a, 40b, 50a, and 50b between the light source 10 and the divided fly-eye lenses 60a and 60b, thereby simplifying the optical system.

  The first collimating lens 20a and the first condenser lens 30a are disposed on the optical path between the light source 10 and the first light beam forming condenser lens 40a. The second collimating lens 20b and the second condenser lens 30b are disposed on the optical path between the light source 10 and the second light beam forming condenser lens 40b.

  The collimating lenses 20a and 20b are optical elements for converting the emitted lights 1a and 1b into parallel lights. A plurality of first collimating lenses 20a are arranged in a one-to-one correspondence with the plurality of emission surfaces 14 of the first emission surface formation region 12a. A plurality of second collimating lenses 20b are arranged in a one-to-one correspondence with the plurality of emission surfaces 14 of the second emission surface formation region 12b. Each of the collimating lenses 20a and 20b can be arranged in a plurality of rows and a plurality of columns, for example, corresponding to the plurality of emission surfaces 14 arranged in a plurality of rows and a plurality of columns. The first collimating lens 20a can convert the first outgoing light 1a into parallel light and make it incident on the first condenser lens 30a. The second collimating lens 20b can convert the second outgoing light 1b into parallel light and make it incident on the second condenser lens 30b. This makes it possible to control the incident angle of the light incident on the light flux forming condenser lenses 40a and 40b, so that the incident angle of the light incident on the split fly-eye lenses 60a and 60b can be easily set by the light flux forming condenser lenses 40a and 40b. Can be controlled. Accordingly, the degree of freedom in designing the optical system can be improved as compared with the case where the outgoing lights 1a and 1b are directly incident on the light flux forming condenser lenses 40a and 40b. Although not shown, the plurality of first collimating lenses 20a and the plurality of second collimating lenses 20b can be integrally formed. Thereby, the collimating lenses 20a and 20b can be formed by a simple process.

  A plurality of first condenser lenses 30a are arranged in a one-to-one correspondence with the plurality of first collimating lenses 20a. A plurality of second condenser lenses 30b are arranged in a one-to-one correspondence with the plurality of second collimating lenses 20b. The condensing lenses 30a and 30b are optical elements for condensing the light converted into parallel light by the collimating lenses 20a and 20b. That is, the light converted into the parallel light by the first collimating lens 20a can be condensed on the first light flux forming condenser lens 40a by the first condenser lens 30a. By the second condenser lens 30b, the light converted into the parallel light by the second collimating lens 20b can be condensed on the second light flux forming condenser lens 40b. Therefore, the light use efficiency can be improved. Further, the collimated lenses 30a and 30b can diverge the parallel light and then diverge it. Therefore, light can be incident on a wide area on the divided fly-eye lenses 60a and 60b.

  The first light beam forming condenser lens 40a is an optical element that superimposes the first outgoing light 1a on the first divided fly-eye lens 60a. Thereby, the 1st light beam 2a is formed. The second light beam forming condenser lens 40b is an optical element that superimposes the second outgoing light 1b on the second divided fly-eye lens 60b. Thereby, the 2nd light beam 2b is formed. That is, the emitted light beams 1a and 1b can be made incident on the split fly-eye lenses 60a and 60b as the light beams 2a and 2b by the light beam forming condenser lenses 40a and 40b. The light beam forming condenser lenses 40a and 40b superimpose light having individual light intensity distributions (for example, Gaussian distributions) emitted from the plurality of emission surfaces 14 on the divided fly-eye lenses 60a and 60b, thereby providing one light intensity. The light beams 2a and 2b having a distribution can be incident. Thereby, the light intensity distribution is made uniform, and the light beams 2a and 2b having high light intensity can be formed. Moreover, since it can superimpose for every output surface formation area 12a, 12b, the incident angle of the light which injects into the division | segmentation fly eye lenses 60a, 60b can be made small. Thereby, the fall of the light transmittance of the condensing fly-eye lenses 70a and 70b can be reduced, for example.

  The first and second field lenses 50a and 50b are optical elements for condensing the light from the light beam forming condenser lenses 40a and 40b on the divided fly-eye lenses 60a and 60b. The first field lens 50a is disposed on the optical path between the first light flux forming condenser lens 40a and the first split fly-eye lens 60a. The second field lens 50b is disposed on the optical path between the second light beam forming condenser lens 40b and the second divided fly-eye lens 60b. The first and second field lenses 50a and 50b allow more light from the light beam forming condenser lenses 40a and 40b to enter the split fly-eye lenses 60a and 60b. Therefore, the light use efficiency can be improved.

  The split fly-eye lenses 60a and 60b are optical elements that split the light beams 2a and 2b into a plurality of partial light beams. In other words, the first split fly-eye lens 60a can divide the first light beam 2a into a plurality of partial light beams and enter the first light-collecting fly-eye lens 70a. The second fly-eye lens 60b can divide the second light beam 2b into a plurality of partial light beams and enter the second light-collecting fly-eye lens 70b. More specifically, the luminous fluxes 2a and 2b are divided into a plurality of partial luminous fluxes by the divided fly-eye lenses 60a and 60b, and individually condensed, and then diverge and enter the condensed fly-eye lenses 70a and 70b. Can do.

  4A is a view of a part of the first divided fly-eye lens 60a as viewed from the Z-axis direction (for example, the incident direction of the first light beam 2a), and FIG. 4B is the second divided eye. It is the figure which looked at a part of fly-eye lens 60b from the Z-axis direction (for example, the incident direction of the 2nd light beam 2b). As shown in FIG. 4, the divided fly-eye lenses 60a and 60b are composed of a plurality of element lenses 62 having the same lens characteristics and the same shape, for example. The element lens 62 of the first divided fly-eye lens 60a and the element lens 62 of the second divided fly-eye lens 60b have, for example, the same lens characteristics and the same shape. By these element lenses 62, the light beams 2a and 2b can be divided into a plurality of partial light beams. The plurality of element lenses 62 are disposed, for example, in an XY plane orthogonal to the Z axis. The plurality of element lenses 62 may be arranged in a plane intersecting the Z axis, for example. The shape (contour shape) of the element lens 62 is a rectangular shape having a long side and a short side when viewed from the Z-axis direction, as shown in FIG. The shape of the element lens 62 is similar to the shape of the incident surface (illuminated region) 112 of the light valve 110, for example. Here, assuming that the axis parallel to the long side of the element lens 62 is the X axis and the axis parallel to the short side is the Y axis, the first divided fly-eye lens 60a has a plurality of rows along the X axis and the Y axis. A plurality of element lenses 62 are arranged in a plurality of rows. Similarly, the second divided fly-eye lens 60b includes a plurality of element lenses 62 arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis. The 1st division | segmentation fly eye lens 60a and the 2nd division | segmentation fly eye lens 60b may be formed integrally.

As shown in FIG. 4, the shape of the first incident area Sa, which is the incident area of the first light beam 2a with respect to the first divided fly-eye lens 60a (see FIG. 4A), and the second shape with respect to the second divided fly-eye lens 60b. The shape of the second incident region Sb that is the incident region of the two light beams 2b (see FIG. 4B) is an elliptical shape having a major axis parallel to the X axis and a minor axis parallel to the Y axis. Here, the incident areas Sa and Sb are a range of intensity in which the light intensity of each of the light beams 2a and 2b irradiating the incident surfaces of the corresponding divided fly-eye lenses 60a and 60b is 1 / e ² with respect to the peak light intensity. I can say that. When the length of the long side of the element lens 62 is Lx and the length of the short side is Ly, the major axis length Bx of the first incident region Sa and the second incident region Sb is 1.2 × Lx ≦ Bx. ≦ 2 × Lx is satisfied, and the minor axis length By of the first incident region Sa and the second incident region Sb satisfies the relationship of 1.2 × Ly ≦ By ≦ 2 × Ly. Further, the length Bx of the major axis and the length By of the minor axis satisfy the relationship Bx: By = Lx: Ly.

  The positional relationship between the first incident region Sa and the element lens 62 is different from the positional relationship between the second incident region Sb and the element lens 62. Specifically, as shown in FIG. 4A, if the common vertex of the four element lenses 62 in the first divided fly-eye lens 60a is a first vertex 63a, the first incident region Sa is, for example, The center of one incident area Sa is an area at a position that coincides with the first vertex 63a. Here, the center of the first incident region Sa can refer to a point where the major axis and the minor axis intersect. As shown in FIG. 4B, when the common vertex of the four element lenses 62 in the second divided fly-eye lens 60b is a second vertex 63b, the second incident region Sb is, for example, the second incident region 2b. The center is a region at a position shifted from the second vertex 63b by 0.5 × Lx along the X axis and 0.5 × Ly along the Y axis. Here, the center of the second incident region Sb is a region at a position shifted by 0.5 × Lx along the X axis and 0.5 × Ly along the Y axis from the second vertex 63b. The center of the two incident areas Sb is shifted from the second vertex 63b by 0.5 Lx in the + X axis direction and 0.5 × Ly in the + Y axis direction, 0.5 × Lx in the −X axis direction, and the −Y axis direction , 0.5 × Lx in the −X axis direction, 0.5 × Lx in the + Y axis direction, 0.5 × Lx in the + X axis direction, − The case where it exists in the position in any position of 0.5xLy shift | offset | differed to the Y-axis direction can be said. The same applies to incident areas Sc and Sd described later. Thus, the light intensity distribution on the incident surface 112 of the light valve 110 is complemented by allowing the first light beam 2a and the second light beam 2b to be incident on the divided fly-eye lenses 60a and 60b in the above-described positional relationship. Thus, illumination light with a uniform light intensity distribution can be obtained. Details and reasons will be described later.

  The distance between the light beam forming condenser lenses 40a and 40b and the divided fly-eye lenses 60a and 60b is, for example, larger than the focal length of the light beam forming condenser lenses 40a and 40b. Thereby, it can prevent that light concentrates on a part of division | segmentation fly eye lenses 60a and 60b, and the uniformity of illumination light falls. Further, the distance between the light beam forming condenser lenses 40a and 40b and the divided fly-eye lenses 60a and 60b is such that the major axis length of the incident areas Sa and Sb is smaller than the effective diameter of the light beam forming condenser lenses 40a and 40b. It is desirable that the distance be Thereby, the light emitted from the element lens 62 of the divided fly-eye lenses 60a and 60b can be made incident on the element lens 72 of the corresponding condensing fly-eye lenses 70a and 70b, thereby improving the light utilization efficiency. Can be planned.

  The condensing fly-eye lenses 70 a and 70 b are optical elements that condense each of the plurality of partial light beams divided by the divided fly-eye lenses 60 a and 60 b onto the light beam superimposing condenser lens 80. That is, the plurality of partial light beams divided by the first split fly-eye lens 60 a can be individually collected by the first condensing fly-eye lens 70 a and incident on the light beam superimposing condenser lens 80. A plurality of partial light beams divided by the second divided fly-eye lens 60 b can be individually collected by the second condensing fly-eye lens 70 b and can be incident on the light beam superimposing condenser lens 80. Thereby, a plurality of partial light beams can be incident on the light beam superimposing condenser lens 80 more. Therefore, the light use efficiency can be improved. The condensing fly-eye lenses 70a and 70b are configured by a plurality of element lenses 72 arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis, similarly to the divided fly eye lenses 60a and 60b. For example, the plurality of element lenses 72 may be arranged in a plane that intersects the Z-axis direction. The element lenses 72 of the condensing fly-eye lenses 70a and 70b can be arranged in a one-to-one correspondence with the element lenses 62 of the divided fly-eye lenses 60a and 60b. The shape of the element lens 72 of the condensing fly-eye lenses 70a and 70b is, for example, the same rectangular shape as the shape of the element lens 62 of the divided fly-eye lenses 60a and 60b when viewed from the Z-axis direction. By configuring the integrator illumination optical system with the divided fly-eye lenses 60a and 60b and the condenser fly-eye lenses 70a and 70b, the illumination light can be made uniform.

  Here, the element lens 72 of the condensing fly-eye lenses 70a and 70b can be formed so that the effective diameter Sf satisfies the following formula (1).

Sf ≧ f2 × Ss / f1 (1)
Where Ss is the effective diameter of the light beam forming condenser lenses 40a and 40b, f1 is the focal length of the light beam forming condenser lenses 40a and 40b, and f2 is the focal point of the element lens 62 of the split fly-eye lenses 60a and 60b. Distance. Thereby, the effective diameter of the element lens 72 of the condensing fly-eye lenses 70a and 70b can be made larger than the beam diameter of the light (partial light flux) incident on the element lens 72. Therefore, the light use efficiency can be improved.

  The light beam superimposing condenser lens 80 is an optical element for superimposing a plurality of partial light beams divided by the divided fly-eye lenses 60a and 60b. That is, the light beam superimposing condenser 80 can superimpose a plurality of partial light beams divided by the divided fly-eye lenses 60a and 60b on the incident surface 112 of the light valve 110, for example. Thereby, the light intensity distribution can be made uniform, and the illuminance unevenness of the illumination light on the incident surface 112 of the light valve 110 can be reduced. For example, one condenser lens 80 is disposed on the optical path of a plurality of partial light beams emitted from the first condensing fly-eye lens 70a and the second condensing fly-eye lens 70b.

  The field lens 90 is an optical element that condenses the light from the light beam superimposing condenser lens 80 on, for example, the incident surface 112 of the light valve 110. The field lens 90 can make more light from the light beam superimposing condenser lens 80 incident on the incident surface 112 of the light valve 110. Therefore, the light use efficiency can be improved. Note that the field lens 90 may not be provided.

  In this embodiment, although the case where the illuminating device 100 which concerns on this embodiment was applied to the illuminating device of a projector was demonstrated, it is not restricted to this, For example, it can also apply to a display, a lighting fixture, etc. The same applies to the embodiments described later.

  The illumination device 100 has the following features, for example.

  According to the illuminating device 100, the first incident region Sa is, for example, a region in which the center of the first incident region Sa is at a position that coincides with the first vertex 63a, and the second incident region Sb is, for example, the second incident region Sa. The center of the incident region 2b can be a region that is shifted from the second vertex 63b by 0.5 × Lx along the X axis and 0.5 × Ly along the Y axis. Thus, by making the first light beam 2a and the second light beam 2b enter the above-described positional relationship with respect to the divided fly-eye lenses 60a and 60b, each light intensity distribution on the incident surface 112 of the light valve 110 is complemented. Thus, illumination light with a uniform light intensity distribution can be obtained. In general, in order to obtain uniform illumination light, many element lenses (for example, several tens or more) need to be included in the incident region of the incident light beam with respect to the divided fly-eye lens. For this purpose, it is necessary to reduce the size of the element lens of the divided fly-eye lens, but it is difficult to manufacture such a divided fly-eye lens. In the illumination device 100, four element lenses 62 are included in the incident area Sa, and nine element lenses 62 are included in the incident area Sb. As described above, in the light emitting device 100, since the number of the element lenses 62 included in the incident areas Sa and Sb is small, the size of the element lens 62 can be increased. Therefore, according to the illuminating device 100, the illumination nonuniformity of illumination light can be reduced and manufacture can be made easy.

  According to the illuminating device 100, the emitted light beams 1a and 1b can be made to be incident on the divided fly-eye lenses 60a and 60b as light beams 2a and 2b by the light beam forming condenser lenses 40a and 40b. Thereby, the light intensity distribution is made uniform, and the light beams 2a and 2b having high light intensity can be formed. Therefore, according to the illuminating device 100, the illumination nonuniformity in the to-be-illuminated area | region 112 can be reduced, and the illumination light which has high light intensity can be obtained.

1.2. First Experimental Example of Lighting Device According to First Embodiment Next, a first experimental example of the lighting device according to this embodiment will be described with reference to the drawings. Specifically, a simulation in a model M1 obtained by modeling the lighting device 100 according to the present embodiment will be described. FIG. 5 is a diagram schematically showing the model M1. FIG. 6 is a plan view schematically showing the light source 10 of the model M1. FIG. 7 is a table showing lens conditions for each lens of the model M1. 8 to 10 are distribution diagrams showing the results of this experimental example.

  In the model M1, the first emitted light 1a emitted from the plurality of emission surfaces 14 arranged in the first emission surface forming region 12a of the light source 10 is converted into the first collimating lens 20a, the first condenser lens 30a, and the first light flux. It travels through the first optical path formed by the forming condenser lens 40a, the first field lens 50a, the first divided fly-eye lens 60a, and the first condensing fly-eye lens 70a, and enters the second emission surface formation region 12b of the light source 10. The second emitted light 1b emitted from the plurality of arranged emission surfaces 14 is converted into the second collimating lens 20b, the second condenser lens 30b, the second light beam forming condenser lens 40b, the second field lens 50b, the second divided fly. The light from the first optical path and the second light travel along the second optical path formed by the eye lens 60b and the second condensing fly-eye lens 70b. The luminous flux superimposing the condenser lens 80 and the light from through the field lens 90, and as forming illumination light by superimposing on the illuminated region 112. The position of the illuminated region 112 where the light beam constituting the illumination light enters is calculated by the ray tracing method. Thereby, the distribution of the number of light rays in the illuminated region 112 was obtained, and the illuminance unevenness of the illumination light was evaluated.

  First, the configuration of the model M1 will be described.

As shown in FIG. 6, the light source 10 has an emission surface arranged along the X axis and the Y axis. The emission surfaces were arranged in 8 rows in the X-axis direction and 20 rows in the Y-axis direction. The surface on which the emission surfaces of the light source 10 are arranged is a square having a side of 16 mm. Interval _{M X} in the X-axis direction of the exit surface, 2.0 mm, spacing _{M Y} in the Y-axis direction was set to 0.8 mm. The surface on which the emission surfaces are arranged is divided into a first emission surface formation region 12a and a second emission surface formation region 12b by a perpendicular bisector P of a side parallel to the Y axis. That is, in each of the emission surface forming regions 12a and 12b, a total of 80 emission surfaces, 8 rows in the X-axis direction and 10 rows in the Y-axis direction, are arranged. The emitted lights 1a and 1b emitted from the emission surface are light emitted from a point light source, and the emission angle is 72 degrees in the X-axis direction and 36 degrees in the Y-axis direction. The total number of light rays emitted from the light source 10 was 2 million.

  The optical system of the model M1 has 80 first collimating lenses 20a and 80 first condensing lenses 30a corresponding to 80 exit surfaces of the first exit surface forming region 12a (for one exit surface). A first collimating lens 20a, a first condensing lens 30a), a first light flux forming condenser lens 40a, a first field lens 50a, a first split fly-eye lens 60a, and a first condensing fly-eye lens. 70a is provided one by one. Similarly, 80 collimating lenses 20b and 80g of second condensing lenses 30b are provided for each of the 80 exit surfaces of the second exit surface formation region 12b (one first surface for one exit surface). 2 collimating lens 20b, one second condensing lens 30b), a first light beam forming condenser lens 40a, a first field lens 50a, a first split fly-eye lens 60a, a first condensing fly-eye lens 70a, a light beam superimposing. One condenser lens 80 and one third field lens 90 are provided. The material of each lens is BK7, and the refractive index is 1.51872. The distance between the lens surface of each lens and the next lens surface, and the radius of curvature of the lens surface are as shown in the table of FIG. In the table shown in FIG. 7, the first surface is a surface on the light incident side, and the second surface is a surface on the light emitting side. That is, the column of the first surface distance indicates the thickness of each lens, and the column of the second surface distance indicates the distance from the second surface to the first surface of the next lens. The column of the distance of the second surface of the field lens 90 indicates the distance to the illuminated area 112. The sign in the radius of curvature column is when + is convex in the −Z direction and − is convex in the + Z direction. Note that the lens conditions of the split and condensing fly-eye lenses 60a, 60b, 70a, and 70b shown in FIG. 7 are the lens conditions of the element lenses 62 and 72. The collimating lenses 20a and 20b and the condensing lenses 30a and 30b are a single lens having one surface as a collimating surface and two surfaces as a condensing surface. The collimating surface was an aspherical surface, and the conic constant was −2.295788. The light collection surface was a spherical surface. The first surface and the second surface of the light beam superimposing condenser lens 80 are aspherical surfaces, the conic constant of the first surface is −0.515799, and the conic constant of the second surface is −817.113. The first and second surfaces of the other lenses 40, 50, 60, 70, 90 were spherical. In the optical system of the model M1, each lens is designed so that the F number is 2.2 or more. In the simulation, the lens loss in each lens is not taken into consideration.

  The element lenses 62 of the divided fly-eye lenses 60a and 60b have a rectangular shape with a long side length Lx of 7.12 mm and a short side length Ly of 4.0 mm. The shape of the element lens 62 is similar to that of the illuminated region 112. The shape of the element lens 72 of the condensing fly-eye lenses 70a and 70b is the same as the shape of the element lens 62 of the divided fly-eye lenses 60a and 60b.

  The first incident area Sa and the second incident area Sb have a major axis length Bx = 1.6 × Lx and a minor axis length By = 1.6 × Ly. Further, Bx: By = Lx: Ly = 1.78: 1. As shown in FIG. 4A, the first incident region Sa is a first region S1 in which the center of the first incident region Sa is at a position that coincides with the first vertex 63a. As shown in FIG. 4B, the second incident region Sb has a center of the second incident region Sb of 0.5 × Lx along the + X axis direction from the second vertex 63b and 0 along the + Y axis direction. The second region S2 is at a position shifted by 5 × Ly.

  Next, simulation results will be described.

  FIG. 8 is a distribution diagram of the number of light rays in the region including the illuminated region 112 when the first incident region Sa shown in FIG. 4A is the first region S1. FIG. 9 is a distribution diagram of the number of light rays in a region including the illuminated region 112 when the second incident region Sb illustrated in FIG. 4B is the second region S2. FIG. 10 is a distribution diagram in which the distribution shown in FIG. 8 and the distribution shown in FIG. 9 are added for each corresponding unit region. The illuminated area 112 is an area within a rectangle having apexes at coordinates (5, 14), (5, 36), (46, 14), and (46, 36). Each unit region was a square with a side length of 0.5 mm. As shown in FIG. 8, the distribution of the number of light rays in the illuminated region 112 when the first incident region Sa is the first region S1 is such that the number of light rays that enter the unit region near the center of the illuminated region 112 is small. Results showing the distribution were obtained. As shown in FIG. 9, the distribution of the number of light rays in the illuminated region 112 when the second incident region Sb is the second region S2 has a large number of light rays that enter the unit region near the center of the illuminated region 112. Results showing the distribution were obtained. Further, as shown in FIG. 10, in the illuminated region 112 obtained by adding the distribution of the number of rays shown in FIG. 8 and the distribution of the number of rays shown in FIG. 9 for each unit region, the distribution of the number of rays. Was found to be uniform. Specifically, the intensity ratio in the illuminated region 112 (ratio of the number of rays in the region with the least number of rays incident on the unit region to the number of rays in the region with the largest number of rays incident on the unit region) is shown in FIG. The distribution of the number of rays shown is 53%, and the distribution of the number of rays shown in FIG. 9 is 70%. On the other hand, in the distribution of the number of rays shown in FIG. 10, the intensity ratio (ratio of the number of rays) is 78%, indicating that the distribution of the number of rays is uniform. As described above, in the model M1, the light intensity distribution can be made uniform by superimposing the light having the light intensity distribution (distribution of the number of light rays) on the illuminated area 112 so as to complement each other. I understood. Therefore, it has been found that the illumination device 100 can obtain light with uniform light intensity distribution in the illuminated region 112, and thus can obtain good illumination light with less uneven illuminance.

  In this experimental example, the center of the second incident region Sb is shifted by 0.5 × Lx in the + X axis direction and 0.5 × Ly in the + Y axis direction from the second vertex 63b. Although the second region S2 is in the position, the second incident region Sb has the center of the second incident region Sb 0.5 × Lx along the X axis from the second vertex 63b and along the Y axis. Any region that is at a position shifted by 0.5 × Ly may be used. That is, the second incident region Sb is located at a position where the center of the second incident region Sb is shifted by 0.5 Lx in the + X axis direction and 0.5 × Ly in the + Y axis direction from the second vertex 63 b, in the −X axis direction. 0.5 × Lx, a position shifted by 0.5 × Ly in the −Y axis direction, a position shifted by 0.5 × Lx in the −X axis direction from the second vertex 63b, and a position shifted by 0.5 × Ly in the + Y axis direction, The region may be located at any position shifted by 0.5 × Lx in the + X-axis direction and 0.5 × Ly in the −Y-axis direction. If the second incident region Sb is such a region, the distribution of the number of rays shown in FIG. 9 described above can be obtained.

  FIG. 11A is a view of a part of the first divided fly-eye lens 60a as viewed from the Z-axis direction, and corresponds to FIG. FIG. 11B is a view of a part of the second divided fly-eye lens 60b as viewed from the Z-axis direction, and corresponds to FIG. 4B. In the simulation result described above, the first incident area Sa is the first area S1 in which the center of the first incident area Sa coincides with the first vertex 63a as shown in FIG. 4A. For example, as shown in FIG. 11A, the first incident region Sa includes the first vertex 63a, and the center of the first light flux 2a is separated from the first vertex 63a by a distance D in a predetermined direction A. It may be a region. In this case, as shown in FIG. 11B, the second incident region Sb is located along the X axis from the position where the center of the second light beam 2b is separated from the second vertex 63b by a distance D in the predetermined direction A. The region may be 0.5 × Lx and a region shifted by 0.5 × Ly along the Y axis. By making the incident areas Sa and Sb each such an area, the distribution of the number of rays in the illuminated area 112 may be a distribution of the number of rays corresponding to positions shifted by the same distance D in the same direction A. it can. Even in this case, the distribution of the number of rays in the illuminated region 112 is in a complementary relationship, and thus a uniform distribution of the number of rays can be obtained as in FIG. Therefore, even when the incident areas Sa and Sb are the above-described areas shown in FIGS. 11A and 11B, good illumination light with little unevenness in illuminance can be obtained in the illuminated area 112.

1.3. Second Experimental Example of Lighting Device According to First Embodiment Next, a second experimental example of the lighting device according to this embodiment will be described with reference to the drawings. In this experimental example, a simulation in a model M2 in which the lighting device 100 is modeled will be described. Specifically, the incident regions Sa and Sb diameter (with respect to the length Lx of the long side) when the light beams 2a and 2b are incident on the divided fly-eye lens 60 corresponding to the divided fly-eye lenses 60a and 60b as the incident beam 2 The ratio of the length Bx of the major axis (Bx / Lx)) and the intensity ratio in the illuminated region (in the region where the light intensity incident on the unit region is the smallest relative to the light intensity in the region where the light intensity incident on the unit region is the largest The relationship of light intensity ratio) was determined. FIG. 12 is a view of a part of the divided fly-eye lens 60 of the model M2 as viewed from the Z-axis direction. FIG. 13 is a graph showing the results of this experimental example.

  First, the calculation method of this simulation will be described.

  In the model M2, the incident light beam 2 has a light intensity distribution with a Gaussian distribution in the incident areas Sa and Sb. The major axis length Bx and minor axis length By of the incident regions Sa and Sb satisfy the relationship Bx: By = Lx: Ly = 2: 1.

  In the divided fly-eye lens 60, as shown in FIG. 12, each element lens 62 is divided into unit areas. In this simulation, first, for each unit area corresponding to each element lens 62, the light intensity of the incident light beam 2 is added to obtain the light intensity distribution in the illuminated area. Specifically, as shown in FIG. 12, the light intensity for each unit region (1, 1), (1, 2)... (N, n) corresponding to each element lens 62a, 62b, 62c, 62d. Are added to obtain the light intensity distribution in the illuminated area. This is performed when the first incident area Sa shown in FIG. 4 (A) is the first area S1 and when the second incident area Sb shown in FIG. 4 (B) is the second area S2. The distribution of light intensity in the illumination area was obtained. The light intensity distribution on the illuminated area thus obtained is added for each unit area to obtain the light intensity distribution on the illuminated area in the model M2. By performing the above-described calculation for each of the incident areas Sa and Sb, the relationship between the incident areas Sa and Sb diameter and the intensity ratio (light intensity ratio) in the illuminated area was obtained.

  Next, simulation results will be described.

  In the model M2, the results shown in FIG. 13 were obtained regarding the relationship between the incident areas Sa and Sb diameters and the intensity ratio (light intensity ratio) in the illuminated area. Since the diameters of the incident areas Sa and Sb satisfy the relationship of Bx: By = Lx: Ly = 2: 1, the ratio of the short axis length By to the short side length Ly (By / Ly) is also the same relationship. It becomes. As shown in FIG. 13, when the incident areas Sa and Sb are in the range of 1.2 or more and 2 or less, the intensity ratio (light intensity ratio) is 80% or more, and the illumination light having a uniform light intensity distribution is obtained. It turns out that it is obtained. That is, it has been found that illumination light with a uniform light intensity distribution can be obtained in the ranges of 1.2 × Lx ≦ Bx ≦ 2 × Lx and 1.2 × Ly ≦ By ≦ 2 × Ly.

2. Second Embodiment 2.1. Illumination Device According to Second Embodiment Next, an illumination device 200 according to the second embodiment will be described. FIG. 14 is a diagram schematically showing the illumination device 200. In addition, in the illuminating device 200 which concerns on 2nd Embodiment, about the member which has the same function as the structural member of the illuminating device 100 which concerns on 1st Embodiment mentioned above, the same code | symbol is attached | subjected and the detailed description is given. Omitted.

  In the illumination device 200, as shown in FIG. 14, the light source 10 supplies the first to fourth light beams 1a, 1b, 1c, and 1d, and correspondingly, the first to fourth divided fly-eye lenses 60a, 60b, 60c, 60d and first to fourth condensing fly-eye lenses 70a, 70b, 70c, 70d are provided.

  In the illumination device 200, the first outgoing light 1 a travels through the first optical path, the second outgoing light 1 b travels through the second optical path, and exits from the outgoing surface 14 arranged in the third outgoing surface formation region 12 c of the light source 10. The third emitted light 1c is a third collimating lens 20c, a third condensing lens 30c, a third light beam forming condenser lens 40c, a third field lens 50c, a third split fly-eye lens 60c, and a third condensing fly. The fourth emitted light 1d traveling on the third optical path formed by the eye lens 70c and emitted from the plurality of emission surfaces 14 arranged in the fourth emission surface forming region 12d of the light source 10 is converted into the fourth collimating lens 20d, The fourth condenser lens 30d, the fourth light flux forming condenser lens 40d, the fourth field lens 50d, the fourth divided fly-eye lens 60d, and the fourth condenser fly-eye lens 70 The light from the first to fourth optical paths is superposed on the incident surface 112 of the light valve 110 via the field lens 90 by the light beam superimposing condenser lens 80. Can be formed.

  The light source 10 includes a first light beam 2a incident on the first divided fly-eye lens 60a, a second light beam 2b incident on the second divided fly-eye lens 60b, a third light beam 2c incident on the third divided fly-eye lens 60c, and A fourth light beam 2d incident on the fourth divided fly-eye lens 60d can be supplied. The light source 10 has first to fourth emission regions 12a, 12b, 12c, and 12d. The light emitted from the emission surface 14 arranged in each of the first to fourth emission regions 12a, 12b, 12c, and 12d is divided into fly beams by, for example, the corresponding light beam forming condenser lenses 40a, 40b, 40c, and 40d. The light beams 2a, 2b, 2c, and 2d are superimposed on the entrance surfaces of the eye lenses 60a, 60b, 60c, and 60d.

  FIG. 15A is a plan view of a part of the third divided fly-eye lens 60c as viewed from the Z-axis direction (for example, the incident direction of the third light beam 2c). FIG. 15B is a plan view of a part of the fourth divided fly-eye lens 60d as viewed from the Z-axis direction (for example, the incident direction of the fourth light beam 2d). As shown in FIG. 15, the third and fourth divided fly-eye lenses 60c and 60d are element lenses 62 arranged in a plurality of rows and a plurality of columns, similarly to the first and second divided fly-eye lenses 60a and 60b. It is configured.

  The shape of the third incident region Sc (see FIG. 15A) and the shape of the fourth incident region Sd (see FIG. 15B) are the same as the shapes of the first and second incident regions Sa and Sb. It has an elliptical shape having a long axis parallel to the X axis and a short axis parallel to the Y axis. The major axis length Bx of the incident regions Sa, Sb, Sc, Sd satisfies the relationship Lx ≦ Bx ≦ 2 × Lx, and the minor axis length By of the incident regions Sa, Sb, Sc, Sd is Ly ≦ The relationship By ≦ 2 × Ly is satisfied. Further, the length Bx of the major axis and the length By of the minor axis satisfy the relationship Bx: By = Lx: Ly.

  The positional relationship of each incident region Sa, Sb, Sc, Sd with respect to each element lens 62 is different from each other. Specifically, the first incident region Sa is, for example, the first region S1 illustrated in FIG. The second incident region Sb is, for example, the second region S2 illustrated in FIG. As shown in FIG. 15 (A), when the common vertex of the four element lenses 62 in the third divided fly-eye lens 60c is the third vertex 63c, the third incident region Sc is, for example, the third incident region Sc. The center is the third region S3 located at a position shifted by 0.5 × Lx along the X axis from the third vertex 63c. Further, as shown in FIG. 15B, if the common vertex of the four element lenses 62 in the fourth divided fly-eye lens 60d is a fourth vertex 63d, the fourth incident region Sd is, for example, a fourth incident region. The center of Sd is the fourth region S4 at a position shifted from the fourth vertex 63d by 0.5 × Lx along the Y axis. In this way, the light flux distribution 2a, 2b, 2c, 2d is made incident on the divided fly-eye lenses 60a, 60b, 60c, 60d in the above-described positional relationship, whereby the light intensity distribution on the incident surface 112 of the light valve 110 is obtained. Is supplemented, and illumination light with a uniform light intensity distribution can be obtained. Details and reasons will be described later.

  According to the illuminating device 200, as with the illuminating device 100, since the number of element lenses 62 constituting the divided fly-eye lenses 60a, 60b, 60c, 60d is small, the size of the element lens 62 can be increased. Therefore, according to the illuminating device 200, the illumination nonuniformity of illumination light can be reduced and manufacture can be facilitated. Details and reasons will be described later.

2.2. First Experimental Example of Lighting Device According to Second Embodiment Next, a first experimental example of the lighting device 200 according to this embodiment will be described with reference to the drawings. Specifically, a simulation in a model M3 obtained by modeling the lighting device 200 according to the present embodiment will be described. Note that differences from Experimental Example 1 according to the first embodiment will be described, and detailed descriptions thereof will be omitted.

  FIG. 16 is a diagram schematically illustrating the model M3. 17 to 21 are distribution diagrams showing the results of this experimental example.

  In the model M3, the first outgoing light 1a travels in the first optical path, the second outgoing light 1b travels in the second optical path, and is emitted from the outgoing surface 14 arranged in the third outgoing surface formation region 12c of the light source 10. The third emitted light 1c is converted into a third collimating lens 20c, a third condenser lens 30c, a third light beam forming condenser lens 40c, a third field lens 50c, a third divided fly-eye lens 60c, and a third condenser fly-eye lens. The fourth emitted light 1d traveling on the third optical path constituted by 70c and emitted from the plurality of emitting surfaces 14 arranged in the fourth emitting surface forming region 12d of the light source 10 is converted into the fourth collimating lens 20d and the fourth collimating lens 20d. A condensing lens 30d, a fourth light flux forming condenser lens 40d, a fourth field lens 50d, a fourth split fly-eye lens 60d, and a fourth condensing fly-eye lens 70d are used. Traveling on the fourth optical path, and the light in the first to fourth optical paths is superimposed on the incident surface 112 of the light valve 110 via the field lens 90 by the light beam superimposing condenser lens 80 to form illumination light. did. The position of the illuminated region 112 where the light beam constituting the illumination light enters is calculated by the ray tracing method. Thereby, the distribution of the number of light rays in the illuminated region 112 was obtained, and the illuminance unevenness of the illumination light was evaluated.

  The light source 10 of the model M3 has first to fourth emission surface formation regions 12a, 12b, 12c, and 12d. Similarly to the model M1, each of the emission surface forming regions 12a, 12b, 12c, and 12d has a total of 80 emission surfaces, 8 rows in the X-axis direction and 10 rows in the Y-axis direction. . The emitted lights 1a, 1b, 1c, and 1d emitted from the emission surface are light emitted from a point light source, and the radiation angle is 60 degrees in the X-axis direction and 30 degrees in the Y-axis direction. The total number of light rays emitted from the light source 10 was 2 million.

  As shown in FIG. 16, in addition to the optical system of model M1, the optical system of model M3 corresponds to the 80 exit surfaces of the third exit surface formation region 12c, the third collimating lens 20c, and the third collection unit. Eighty optical lenses 30c are provided, and a third light flux forming condenser lens 40c, a third field lens 50c, a third divided fly-eye lens 60c, and a third condensing fly-eye lens 70c are provided one by one. It was supposed to be. Similarly, 80 pieces of the fourth collimating lens 20d and the fourth condenser lens 30d are provided corresponding to the 80 outgoing faces of the fourth outgoing face forming area 12d, and the fourth luminous flux forming condenser lens 40d, The four field lens 50d, the fourth divided fly-eye lens 60d, and the fourth condensing fly-eye lens 70d are provided one by one. The distance between the lens surface of each lens and the next lens surface, and the radius of curvature of the lens surface are the same as in the first experimental example according to the first embodiment shown in FIG.

  The incident areas Sa, Sb, Sc, and Sd have a major axis length Bx = 1.6 × Lx and a minor axis length By = 1.6 × Ly. Further, Bx: By = Lx: Ly = 1.78: 1. The first incident area Sa is the first area S1 shown in FIG. The second incident region Sb is the second region S2 shown in FIG. As shown in FIG. 15A, the third incident region Sc is the same as the third region S3 in which the center of the third incident region Sc is shifted by 0.5 × Lx in the + X axis direction from the third vertex 63c. did. As shown in FIG. 15B, the fourth incident region Sd is the same as the fourth region S4 in which the center of the fourth incident region Sd is at a position shifted by 0.5 × Ly in the + Y-axis direction from the fourth vertex 63d. did.

  Next, simulation results will be described.

  FIG. 17 is a distribution diagram of the number of light rays in the region including the illuminated region 112 when the first incident region Sa shown in FIG. 4A is the first region S1. FIG. 18 is a distribution diagram of the number of rays in a region including the illuminated region 112 when the second incident region Sb illustrated in FIG. 4B is the second region. FIG. 19 is a distribution diagram of the number of light rays in the region including the illuminated region 112 when the third incident region Sc shown in FIG. 15A is the third region S3. FIG. 20 is a distribution diagram of the number of rays in an area including the illuminated area 112 when the fourth incident area Sd shown in FIG. 15B is the fourth area. FIG. 21 is a distribution diagram in which the distributions shown in FIGS. 17 to 20 are added for each corresponding unit region.

  As shown in FIG. 17, the distribution of the number of light rays in the illuminated region 112 when the first incident region Sa is the first region S1 is such that the number of light rays that enter the unit region near the center of the illuminated region 112 is small. Distribution. As shown in FIG. 18, the distribution of the number of light rays in the illuminated region 112 when the second incident region Sb is the second region S2 has a large number of light rays that enter the unit region near the center of the illuminated region 112. Distribution. As shown in FIG. 19, the distribution of the number of light rays when the third incident region Sc is the third region S3 is a distribution in which the region near the long side of the illuminated region has a large number of light rays incident on the unit region. . As shown in FIG. 20, the distribution of the number of light rays when the fourth incident region Sd is the fourth region S4 is a distribution in which the region near the short side of the illuminated region has a large number of light rays incident on the unit region. . Further, as shown in FIG. 21, in the illuminated region 112 obtained by adding the distribution of the number of rays shown in FIGS. 17 to 20 for each unit region, it is understood that the distribution of the number of rays is uniform. It was. Specifically, the intensity ratio (ratio of the number of rays) in the illuminated region 112 is 32% in the distribution of the number of rays shown in FIG. 17, and 45% in the distribution of the number of rays shown in FIG. In the distribution of the number of rays shown in FIG. 19, it was 43%, and in the distribution of the number of rays shown in FIG. 20, it was 37%. On the other hand, in the distribution of the number of rays shown in FIG. 21, the intensity ratio (ratio of the number of rays) is 79%, and it was found that the distribution of the number of rays is uniform. As described above, in the model M3, the light intensity distribution can be made uniform by superimposing the light having the light intensity distribution (distribution of the number of light rays) on the illuminated area 112 so as to complement each other. I understood. Therefore, it has been found that the illumination device 200 can obtain light with a uniform light intensity distribution in the illuminated region 112, and thus can obtain good illumination light with little illuminance unevenness.

2.3. Second Experimental Example of Lighting Device According to Second Embodiment Next, a second experimental example of the lighting device 200 according to this embodiment will be described with reference to the drawings. In this experimental example, a simulation in a model M4 that models the lighting device 200 will be described. Specifically, the incident regions Sa, Sb, when the light beams 2a, 2b, 2c, and 2d are incident on the divided fly-eye lens 60 corresponding to the divided fly-eye lenses 60a, 60b, 60c, and 60d as the incident light beam 2 The relationship between the Sc and Sd diameters and the intensity ratio (light intensity ratio) in the illuminated area was determined. FIG. 22 is a graph showing the results of this experimental example. Note that differences from Experimental Example 2 according to the first embodiment will be described, and detailed descriptions thereof will be omitted.

  In the present experimental example, the first incident region Sa is the first region S1, the second incident region Sb is the second region S2, and the third incident is performed in the same manner as the experimental example 2 according to the first embodiment. The distribution of the number of rays in the illuminated area when the area Sc is the third area S3 and the fourth incident area Sd is the fourth area S4 is calculated, and the incident areas Sa, Sb, Sc, and Sd diameter in the model M4 are calculated. The relationship of the intensity ratio (light intensity ratio) in the illuminated area was determined.

  In such a model M4, the result as shown in FIG. 21 was obtained regarding the relationship between the incident areas Sa, Sb, Sc, Sd diameter and the intensity ratio (light intensity ratio) in the illuminated area. As shown in FIG. 21, when the incident areas Sa, Sb, Sc, and Sd are in the range of 1.0 to 2.0, the intensity ratio (light intensity ratio) is 80% or more, and the light intensity distribution is uniform. It turned out that the illuminating illumination light was obtained. That is, it has been found that illumination light with a uniform light intensity distribution can be obtained in the ranges of Lx ≦ Bx ≦ 2 × Lx and Ly ≦ By ≦ 2 × Ly.

3. Third Embodiment Next, a projector 300 according to a third embodiment will be described. FIG. 23 is a diagram schematically illustrating the projector 300. In FIG. 23, for convenience, the casing constituting the projector 300 is omitted. The projector 300 includes the lighting device according to the present invention. Below, the example using the illuminating device 100 is demonstrated as an illuminating device which concerns on this invention.

  In the projector 300, the red illumination device 100R, the green illumination device 100G, and the blue illumination device 100B that emit red light, green light, and blue light are the illumination devices 100 described above.

  The projector 400 includes transmissive liquid crystal light valves (light modulation devices) 304R, 304G, and 304B that modulate light emitted from the illumination devices 100R, 100G, and 100B in accordance with image information, and liquid crystal light valves 304R, 304G, and A projection lens (projection device) 308 that magnifies and projects the image formed by 304B onto a screen (display surface) 310; In addition, the projector 300 can include a cross dichroic prism (color light combining unit) 306 that combines the light emitted from the liquid crystal light valves 304R, 304G, and 304B and guides the light to the projection lens 308.

  The three color lights modulated by the liquid crystal light valves 304R, 304G, and 304B enter the cross dichroic prism 306. This prism is formed by bonding four right-angle prisms, and a dielectric multilayer film that reflects red light and a dielectric multilayer film that reflects blue light are arranged in a cross shape on the inner surface thereof. These dielectric multilayer films combine the three color lights to form light representing a color image. The synthesized light is projected onto the screen 310 by the projection lens 306, which is a projection optical system, and an enlarged image is displayed.

  In the above example, a transmissive liquid crystal light valve is used as the light modulation device. However, a light valve other than liquid crystal may be used, or a reflective light valve may be used. Examples of such a light valve include a reflective liquid crystal light valve and a digital micromirror device. Further, the configuration of the projection optical system is appropriately changed depending on the type of light valve used.

  In addition, the illumination apparatus 100 scans the light from the illumination apparatus 100 on the screen, and thus has a scanning unit that is an image forming apparatus that displays an image of a desired size on the display surface. The present invention can also be applied to a lighting device of a device (projector).

  According to the projector 300, since the illumination device that can reduce the illuminance unevenness is used, an image with little illuminance unevenness can be projected.

  The above-described embodiment is an example, and the present invention is not limited to these. For example, the above-described embodiments can be appropriately combined.

  Although the embodiments of the present invention have been described in detail as described above, those skilled in the art will readily understand that many modifications are possible without substantially departing from the novel matters and effects of the present invention. Accordingly, all such modifications are intended to be included in the scope of the present invention.

10 light source, 12a first emission surface formation region, 12b second emission surface formation region,
12c third exit surface formation region, 12d fourth exit surface formation region, 14 exit surface,
20a first collimating lens, 20b second collimating lens,
20c 3rd collimating lens, 20d 4th collimating lens,
30a first condenser lens, 30b second condenser lens, 30c third condenser lens,
30d fourth condenser lens, 40a first light beam condenser lens,
40b second light beam forming condenser lens, 40c third light beam forming condenser lens,
40d Fourth light flux forming condenser lens, 50a first field lens,
50b second field lens, 50c third field lens,
50d 4th field lens, 60a 1st divided fly-eye lens,
60b second divided fly-eye lens, 60c third divided fly-eye lens,
60d Fourth divided fly-eye lens, 62 element lens, 63a first vertex,
63b 2nd vertex, 63c 3rd vertex, 64c 4th vertex,
70a first condensing fly-eye lens, 70b second condensing fly-eye lens,
70c third condensing fly-eye lens, 70d fourth condensing fly-eye lens,
72 element lens, 80 luminous flux condenser lens,
90 third field lens, 100 lighting device, 110 light valve,
112 incident surface (illuminated area), 200 illumination device, 300 projector,
304 Liquid crystal light valve, 306 Cross dichroic prism,
308 projection lens, 310 screen

Claims (8)

A light source for supplying a first light beam and a second light beam;
A first split fly-eye lens that splits the first light flux into a plurality of partial light fluxes;
A second split fly-eye lens that splits the second light flux into a plurality of partial light fluxes;
A first condensing fly-eye lens that individually collects the plurality of partial light beams divided by the first divided fly-eye lens;
A second condensing fly-eye lens that individually collects the plurality of partial light beams divided by the second divided fly-eye lens;
Light flux superimposition for superimposing the plurality of partial light fluxes collected by the first light collection fly-eye lens and the plurality of partial light fluxes collected by the second light collection fly-eye lens on an illuminated area A condenser lens,
Including
The first divided fly-eye lens and the second divided fly-eye lens are composed of rectangular element lenses having a long side and a short side,
The element lenses of the first split fly-eye lens are arranged in a plurality of rows and columns along an X axis parallel to the long side and a Y axis parallel to the short side,
The element lenses of the second divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The shape of the first incident region of the first light beam with respect to the first divided fly-eye lens and the shape of the second incident region of the second light beam with respect to the second divided fly-eye lens are long axes parallel to the X axis. And a short axis parallel to the Y-axis,
The length of the long side of the element lens is Lx,
The length of the short side of the element lens is Ly,
The major axis length Bx satisfies a relationship of 1.2 × Lx ≦ Bx ≦ 2 × Lx, and the minor axis length By satisfies a relationship of 1.2 × Ly ≦ By ≦ 2 × Ly, The length Bx of the major axis and the length By of the minor axis satisfy the relationship Bx: By = Lx: Ly,
The first incident area includes a first vertex common to the four element lenses in the first split fly-eye lens, and the center of the first light flux is separated from the first vertex by a distance D in a predetermined direction. Area,
The second incident region has a position where the center of the second light flux is separated from the second vertex common to the four element lenses in the second divided fly-eye lens by the distance D in the predetermined direction. A lighting device that is a region shifted by 0.5 × Lx along the X axis and 0.5 × Ly along the Y axis. In claim 1,
The light source has a first emission surface formation region and a second emission surface formation region in which a plurality of emission surfaces are arranged,
A first light beam forming condenser lens that superimposes the light emitted from the plurality of emission surfaces of the first emission surface formation region on the first divided fly-eye lens to form the first light beam;
A second light beam forming condenser lens that superimposes the light emitted from the plurality of emission surfaces of the second emission surface forming region on the second divided fly-eye lens to form the second light beam;
A lighting device. In claim 2,
The distance between the first light beam forming condenser lens and the first split fly-eye lens is larger than the focal length of the first light beam forming condenser lens, and the length of the major axis of the first incident region is the first distance. It is a distance that is smaller than the effective diameter of a single beam forming condenser lens,
The distance between the second light beam forming condenser lens and the second split fly-eye lens is larger than the focal length of the second light beam forming condenser lens, and the length of the major axis of the second incident region is the first distance. A lighting device having a distance smaller than the effective diameter of the two-beam forming condenser lens. In claim 2 or 3,
A plurality of first collimating lenses arranged corresponding to the plurality of emission surfaces of the first emission surface forming region and individually converting light emitted from the plurality of emission surfaces into parallel light;
A plurality of first condensing lenses arranged corresponding to the first collimating lens and individually condensing the parallel light converted by the first collimating lens on the first light flux forming condenser lens;
A plurality of second collimating lenses that are arranged corresponding to the plurality of emission surfaces of the second emission surface forming region and individually convert the light emitted from the plurality of emission surfaces into parallel light;
A plurality of second condensing lenses arranged corresponding to the second collimating lenses and individually condensing the parallel light converted by the second collimating lenses on the second light flux forming condenser lens;
Further including
The first collimating lens and the first condenser lens are disposed on an optical path between the light source and the first light beam forming condenser lens,
The lighting device, wherein the second collimating lens and the second condenser lens are disposed on an optical path between the light source and the second light beam forming condenser lens. In any one of Claims 2 thru | or 4,
A light beam is disposed on an optical path between the first light beam forming condenser lens and the first divided fly-eye lens, and condenses light emitted from the first light beam forming condenser lens on the first divided fly-eye lens. 1 field lens,
A second light beam is disposed on the optical path between the second light beam forming condenser lens and the second divided fly-eye lens, and condenses the light emitted from the second light beam forming condenser lens on the second divided fly-eye lens. Two field lenses,
A lighting device. A light source for supplying a first light beam, a second light beam, a third light beam, and a fourth light beam;
A first split fly-eye lens that splits the first light flux into a plurality of partial light fluxes;
A second split fly-eye lens that splits the second light flux into a plurality of partial light fluxes;
A third split fly-eye lens that splits the third light flux into a plurality of partial light fluxes;
A fourth split fly-eye lens that splits the fourth light flux into a plurality of partial light fluxes;
A first condensing fly-eye lens that individually collects the plurality of partial light beams divided by the first divided fly-eye lens;
A second condensing fly-eye lens that individually collects the plurality of partial light beams divided by the second divided fly-eye lens;
A third condensing fly-eye lens that individually collects the plurality of partial light beams divided by the third divided fly-eye lens;
A fourth condensing fly-eye lens that individually collects the plurality of partial light beams divided by the fourth divided fly-eye lens;
The plurality of partial light beams collected by the first light collection fly-eye lens, the plurality of partial light beams collected by the second light collection fly-eye lens, and the third light collection fly-eye lens. A light beam superimposing condenser lens that superimposes the plurality of emitted partial light beams and the plurality of partial light beams collected by the fourth condensing fly-eye lens on an illuminated area;
Including
The first, second, third, and fourth divided fly's eye lenses are composed of rectangular element lenses having a long side and a short side,
The element lenses of the first split fly-eye lens are arranged in a plurality of rows and columns along an X axis parallel to the long side and a Y axis parallel to the short side,
The element lenses of the second divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The element lenses of the third divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The element lenses of the fourth divided fly-eye lens are arranged in a plurality of rows and a plurality of columns along the X axis and the Y axis,
The shape of the first incident region of the first light beam with respect to the first divided fly-eye lens, the shape of the second incident region of the second light beam with respect to the second divided fly-eye lens, and the first shape with respect to the third divided fly-eye lens The shape of the third incident region of the three light beams and the shape of the fourth incident region of the fourth light beam with respect to the fourth divided fly-eye lens are a long axis parallel to the X axis and a short axis parallel to the Y axis. An elliptical shape having
The length of the long side of the element lens is Lx,
The length of the short side of the element lens is Ly,
The major axis length Bx satisfies a relationship of 1.2 × Lx ≦ Bx ≦ 2 × Lx, and the minor axis length By satisfies a relationship of 1.2 × Ly ≦ By ≦ 2 × Ly, The length Bx of the major axis and the length By of the minor axis satisfy the relationship Bx: By = Lx: Ly,
The first incident region includes a first vertex that is a common vertex of the four element lenses in the first split fly-eye lens, and a center of the first light flux is a distance from the first vertex in a predetermined direction. Is a region separated by D,
The second incident region is a position where the center of the second light flux is separated from the second vertex, which is a common vertex of the four element lenses in the second divided fly-eye lens, by the distance D in the predetermined direction. From 0.5 × Lx along the X axis and 0.5 × Ly along the Y axis,
The third incident area is a position where the center of the third light flux is separated from the third vertex, which is a common vertex of the four element lenses in the third divided fly-eye lens, by the distance D in the predetermined direction. Is a region shifted by 0.5 × Lx along the X-axis,
The fourth incident area is a position where the center of the fourth light flux is separated from the fourth vertex, which is a common vertex of the four element lenses in the fourth divided fly-eye lens, by the distance D in the predetermined direction. The lighting device is a region shifted by 0.5 × Ly along the Y axis. In any one of Claims 1 thru | or 6,
The illuminating device, wherein the light source is any one of a semiconductor laser, a super luminescent diode, and a light emitting diode. The lighting device according to any one of claims 1 to 7,
A light modulation device that modulates light emitted from the illumination device according to image information;
A projection device for projecting an image formed by the light modulation device;
Including projector.