JP3610804B2 - Illumination device and projection display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an illumination device suitable for irradiating a uniform illumination light to a light valve that modulates light according to image information, and a light beam from the illumination device to modulate and project an enlarged light beam. The present invention relates to a projection display device.
[0002]
[Prior art]
FIG. 8 is a diagram showing an example of a conventional projection display device. In the conventional projection display apparatus shown in FIG. 8, the light emitted from the lamp 10 via the uniform illumination optical system 20 is converted into red (R), green (G), blue ( After being separated into the three colors of light B), the light is collimated by the condenser lens 100 and incident on the liquid crystal panel 51 corresponding to each color (R, G, B), and is modulated by the liquid crystal panel 51 according to the image information. The light of each color modulated by the prism 61 is synthesized and enlarged and projected on the screen S through the projection lens 71.
[0003]
The uniform illumination optical system 20 includes a first lens array 21, a second lens array 22, and a condenser lens 23. The uniform illumination optical system 20 divides the light emitted from the lamp 10 into a plurality of partial light beams by the first lens array 21, and each partial light beam is passed through the second lens array 22 and the condenser lens 23. By superimposing on the liquid crystal panel 51, the liquid crystal panel 51 has a function to make the in-plane intensity of light irradiated uniform.
[0004]
[Problems to be solved by the invention]
FIG. 9A, FIG. 9B, FIG. 10A, and FIG. 10B are diagrams for explaining problems of the uniform illumination optical system of the conventional projection display device. As shown in FIG. 9A, the lamp 10 has an illuminance distribution in which the light intensity near the optical axis L is high and the light intensity decreases as the distance from the optical axis L increases. Accordingly, a light beam having a non-uniform intensity on the incident surface is incident on each of the small lenses a to f as shown in the distance D-light intensity I characteristic in FIG. 9A and in FIG. 9B. Moreover, in the small lenses a and f, when the position of the optical axis L is taken as a reference, the intensity distribution in the incident surface is reversed, and similarly, the small lenses b and e, c and d are also in the incident surface. The intensity distribution is reversed. Therefore, at points A and B near the end of the liquid crystal panel 51, as shown in FIG. ₁ ~ L ₆ , L ₁ '~ L ₆ 'Will be incident. Specifically, light having an angle and intensity as indicated by a solid line in FIG. 10B is incident on point A, and angle and intensity as indicated by a dotted line in FIG. Light is incident. As can be seen from this figure, at point A, the amount of light on the + θ side is much larger than that on the −θ side, and at point B, the amount of light on the −θ side is much larger than the amount of light on the + θ side.
[0005]
On the other hand, the contrast of the image displayed by the liquid crystal panel 51 depends on the incident angle of light, and there is an angle at which the contrast is highest on either the + θ side or the −θ side. Here, if there is an angle at which the contrast is highest on the + θ side, the amount of light on the + θ side is large at the point A, and conversely, the amount of light on the + θ side is small at the point B. Therefore, the brightness of the projected image is uneven. Further, there is color light that passes through the film formed in the prism 61 and color light that is reflected by the film, and the image of the transmitted color light and the image of the reflected color light are inverted with respect to each other. Accordingly, the tendency of uneven brightness is also reversed between these images, and uneven color occurs in the projected image. Furthermore, the occurrence of such brightness unevenness and color unevenness also reduces the contrast of the projected image.
[0006]
In order to solve this problem, if the number of small lens divisions of the first lens array 21 is made fine, the peaks in FIG. 10B increase, and the intensity difference between the peaks relatively decreases. Uniformity on the left and right is improved. However, there is a demand for miniaturization of the projection display device, and the number of divisions is determined by the distance between the uniform illumination optical system 20 and the liquid crystal panel 51. Therefore, the projection display device must be subdivided until the uniformity of the angular distribution is satisfied. I can't.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems and to make the incident angle to the light modulation means and the light intensity uniform, thereby reducing the uneven color of the projected image and improving the contrast. And a projection display device.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, a first invention provides a light source, a first lens array that divides light emitted from the light source into a plurality of partial light beams, and a light emitting side of the first lens array. A second lens array disposed, wherein the first lens array has a plurality of small lenses arranged two-dimensionally, and the second lens array comprises: At least a pair of first lenses having a plurality of small lenses arranged in a two-dimensional manner and existing at point-symmetrical positions with respect to the optical axis of the light source among the small lenses constituting the first lens array. The light emitted from the small lenses is positioned relative to the pair of second small lenses corresponding to the pair of first small lenses among the small lenses constituting the second lens array. It is characterized by being incident so as to change It is a lighting device. Thereby, it is possible to reduce the uneven color of the projected image and improve the contrast.
[0009]
According to a second aspect of the present invention, in the illumination device according to the first aspect of the invention, the pair of first small lenses and the pair of second small lenses are composed of eccentric lenses. It is.
[0010]
A third invention is an illumination device according to the first or second invention, wherein the pair of first small lenses are small lenses having the largest amount of incident light. is there. For this reason, the degree of uniformity of the light quantity is improved, which is more effective.
[0011]
According to a fourth aspect of the present invention, there is provided a light source, a first lens array that divides light emitted from the light source into a plurality of partial light beams, and a second lens array that is disposed on a light emission side of the first lens array. The first lens array has a plurality of small lenses arranged two-dimensionally, and the second lens array is a plurality of two-dimensionally arranged lenses. Among the small lenses constituting the first lens array, at least a pair of first lenses existing at positions symmetrical with respect to a boundary line of the small lens including the optical axis of the light source. The light emitted from the small lenses is switched in position with respect to the pair of second small lenses corresponding to the pair of first small lenses among the small lenses constituting the second lens array. It is characterized by being incident on It is a lighting device. Thereby, it is possible to reduce the uneven color of the projected image and improve the contrast.
[0012]
According to a fifth invention, in the illumination device according to the fourth invention, a prism for changing an optical path is disposed in an optical path between the light source and the pair of first small lenses. A prism for changing the optical path is disposed in the optical path between the small lens and the pair of second small lenses or on the light emission side of the pair of second small lenses. It is. Since it is sufficient to arrange a prism, it is not necessary to change the shape of the small lens, and the manufacture is facilitated.
[0013]
According to a sixth invention, in the illumination device according to the fourth invention, a prism for changing an optical path is disposed in an optical path between the pair of first small lenses and the pair of second small lenses. A prism that changes the optical path is disposed in the optical path between the pair of first small lenses and the pair of second small lenses or on the light emission side of the pair of second small lenses. It is the illuminating device characterized by these. Since it is sufficient to arrange a prism, it is not necessary to change the shape of the small lens, and the manufacture is facilitated.
[0014]
According to a seventh invention, in the illumination device according to the fourth invention, the pair of first small lenses and the pair of second small lenses are constituted by eccentric lenses. It is.
[0015]
An eighth invention is the illumination device according to any one of the fourth to seventh inventions, wherein the pair of first small lenses are small lenses having the largest amount of incident light. It is an illuminating device.
[0016]
The ninth invention is separated by the illumination device according to any one of the first to sixth inventions, color separation means for separating light from the illumination device into light beams of three primary colors, and the color separation means. Light modulating means for optically modulating the light beams of the respective colors in correspondence with image information, color combining means for combining the modulated light beams modulated by the light modulating means, and enlargement projection of the combined light beams synthesized by the color combining means A projection display device. As a result, the angular distribution of the incident light incident on the light modulation means can be made uniform, so that the color unevenness of the projected image can be reduced and the contrast can be improved.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.
[0018]
(First embodiment)
FIG. 1 is a schematic diagram showing a first embodiment of an illumination device and a projection display device according to the present invention, and FIG. 2 is a simplified equivalent optical system of the illumination device and the projection display device according to the first embodiment. FIG. 3 is a diagram showing the first lens array extracted from the illumination device and the projection display device according to the first embodiment. The illumination device 1A according to the first embodiment includes a light source 10 and a uniform illumination optical system 20A.
[0019]
The light source 10 includes a light source lamp 11 and a curved reflecting mirror 12. As the light source lamp 11, a halogen lamp, a metal halide lamp, a xenon lamp, or the like can be used.
[0020]
As shown in FIG. 2, the uniform illumination optical system 20A divides the light beam emitted from the light source 10 into a plurality of partial light beams, and superimposes the partial light beams on the liquid crystal panels 51R, 51G, and 51B, thereby liquid crystal. It has a function of illuminating the panels 51R, 51G, 51B with substantially uniform illuminance. The first lens array 21A has a plurality of rectangular lenses arranged in a matrix, divides a light beam emitted from the light source 10 into a plurality of partial light beams, and each partial light beam is a second lens array 22A. Concentrate in the vicinity of The second lens array 22A has a plurality of rectangular lenses arranged in a matrix, and the central optical path of each partial light beam emitted from the first lens array 21A with respect to the optical axis L of the light source 10 Has the function of aligning in parallel. The uniform illumination optical system 20A of the example shown in FIG. 1 includes a mirror 24 that bends the optical axis L in the front direction of the apparatus. Has been. A condenser lens 23 is disposed on the emission surface side of the second lens array 22A. The condenser lens 23 has a function of superimposing the partial light beams on the liquid crystal panels 51R, 51G, and 51B. Thus, in the projection display apparatus 1A of the present example, the uniform illumination optical system 20A can illuminate the liquid crystal panels 51R, 51G, and 51B with light with substantially uniform illuminance. Can be obtained.
[0021]
As shown in FIG. 1, the projection display device 2A according to the first embodiment converts a light beam W emitted through the uniform illumination optical system 20 of the illumination device 1A into red, green, and blue color light beams R, G, A color separation optical system 40 for separating the light into B, three liquid crystal panels 51R, 51G, and 51B as light modulation means 50 for modulating each color light beam, and a prism as a color composition optical system 60 for combining the modulated color light beam 61 and a projection lens 71 as a projection optical system 70 for enlarging and projecting the combined light flux on the screen S. Of the color beams separated by the color separation optical system 40, Blue light flux B Corresponding liquid crystal panel 51 B A relay lens system 90 is provided.
[0022]
The color separation optical system 40 includes a blue-green reflecting dichroic mirror 41, a green reflecting dichroic mirror 42, and a reflecting mirror 43. Of the light W emitted from the uniform illumination optical system 20, first, the blue light B and the green light G included in the blue-green reflection dichroic mirror 41 are reflected at right angles, and the green reflection dichroic mirror 42 Head to the side. The red light R passes through the mirror 41, is reflected at a substantially right angle by the rear reflecting mirror 43, and is emitted from the red light emitting portion 44 to the color synthesis optical system side.
[0023]
Next, of the blue and green lights B and G reflected by the mirror 41, Green In the reflective dichroic mirror 42, only the green light G is reflected substantially at a right angle and emitted from the green light emitting portion 45 to the prism 61 side. The blue light B that has passed through the mirror 42 is emitted from the blue light emitting portion 46 toward the relay lens system 90. In the present embodiment, the distance from the light emitting portion of the uniform illumination optical system 20A to the light emitting portions 44, 45, and 46 of each color light in the color separation optical system 40 is set to be substantially equal.
[0024]
Here, in the present embodiment, condensing lenses 101 and 102 made of plano-convex lenses are arranged on the emission side of the red light emission unit 44 and the green light emission unit 45 of the color separation optical system 40, respectively. Yes. The red light R and the green light G emitted from each of the emission units 44 and 45 are incident on these condenser lenses 101 and 102 and are collimated.
[0025]
Of the light collimated in this way, red light R and Green light G After passing through a polarizing plate (not shown) and the polarization direction is aligned, the light enters the liquid crystal panels 51R and 51G disposed immediately after the condenser lenses 101 and 102 and is modulated. Then, image information corresponding to each color light is added. The liquid crystal panels 51R and 51G are subjected to switching control according to image information by a driving unit (not shown), and thereby each color light passing therethrough is modulated. As such driving means, known means can be used as they are, and the description thereof is omitted in this embodiment.
[0026]
On the other hand, the blue light B passes through the relay lens system 90, and further passes through a polarizing plate (not shown) and is aligned in the polarization direction, and then guided to the corresponding liquid crystal panel 51B. Then, similarly to the other color lights, modulation according to the image information is performed. The liquid crystal panels 51R, 51G, and 51B of the present embodiment are those using polysilicon TFTs as switching elements.
[0027]
The relay lens system 90 includes an incident-side reflecting mirror 91, an emitting-side reflecting mirror 92, an intermediate lens 93 disposed therebetween, a condensing lens 103, and a condensing lens 104. Since the blue light B has the longest optical path length of each color light, that is, the distance from the light source lamp 11 to each liquid crystal panel, the light quantity loss of this light is the largest. However, the loss of light quantity can be suppressed by interposing the relay lens system 90 as in this embodiment. The colored light that passes through the relay lens system 90 may be red or green light.
[0028]
Next, out of the color beams modulated through the liquid crystal panels 51R, 51G, and 51B, only light of one kind of polarization direction that has passed through a polarizing plate (not shown) is incident on the prism 61 and synthesized there. . In the present embodiment, the prism 61 used as the color synthesis optical system 60 is a dichroic prism in which two types of dichroic films are formed in an X shape along the interface of the four prisms. As the color synthesis optical system 60, it is also possible to use a cross mirror having a configuration in which two types of dichroic mirrors are arranged in an X shape or a mirror synthesis system having a configuration in which two types of dichroic mirrors are separately arranged.
[0029]
In the present embodiment, the problems in the conventional technology are solved by the following configuration. FIG. 3A is a diagram of the first lens array 21A viewed in the z direction, and FIG. 3B is a diagram of the second lens array 22A viewed in the z direction. The center of the cross shape shown in FIGS. 3A and 3B means the position of the optical axis of each small lens. As shown in FIG. 3A, the first lens array 21A includes a small lens a having 8 rows and 6 columns two-dimensionally. ₁ ~ A ₈ , B ₁ ~ B ₈ , C ₁ ~ C ₈ , D ₁ ~ D ₈ , E ₁ ~ E ₈ , F ₁ ~ F ₈ Are arranged. On the other hand, as shown in FIG. 3B, the second lens array 22A is also two-dimensionally arranged with a small lens a having 8 rows and 6 columns. ₁ '~ A ₈ ', B ₁ '~ B ₈ ', C ₁ '~ C ₈ ', D ₁ '~ D ₈ ', E ₁ '~ E ₈ ', F ₁ '~ F ₈ 'Is arranged. Here, each small lens a of the first lens array 21A. ₁ ~ A ₈ , B ₁ ~ B ₈ , C ₁ ~ C ₈ , D ₁ ~ D ₈ , E ₁ ~ E ₈ , F ₁ ~ F ₈ Is arranged in the small lens a of the second lens array 22. ₁ '~ A ₈ ', B ₁ '~ B ₈ ', C ₁ '~ C ₈ ', D ₁ '~ D ₈ ', E ₁ '~ E ₈ ', F ₁ '~ F ₈ Corresponds to each. Among the small lenses of the first lens array 21A, the small lens c ₄ , C ₅ , D ₄ , D ₅ Of the second lens array 22A, a small lens c ₄ ', C ₅ ', D ₄ ', D ₅ 'Is composed of an eccentric lens, and each optical axis is set closer to the light source optical axis than the position of the geometric center of each lens.
[0030]
Then, by using such lens arrays 21A and 22A, as shown in FIG. 2, the small lens c of the first lens array ₄ , C ₅ , D ₄ , D ₅ The luminous flux emitted from the second lens array ₅ ', D ₄ ', C ₅ ', C ₄ ', Respectively. That is, in the first lens array 21A, the small lens c existing at a point-symmetrical position with respect to the optical axis L of the light source. ₄ And d ₅ The light emitted from the small lens c existing in a position geometrically corresponding to these small lenses in the second lens array 2A. ₄ 'And d ₅ 'Are incident so that their positions are interchanged with each other. Further, in the first lens array 21A, the small lens c existing in a point-symmetrical position with respect to the optical axis L of the light source. ₅ And d ₄ The light emitted from the small lens c existing in a position geometrically corresponding to these small lenses in the second lens eye 22A. ₅ 'And d ₄ 'Are incident so that their positions are interchanged with each other. Note that light beams emitted from the other small lenses of the first lens array 21A are incident on the corresponding small lenses of the second lens array 22A.
[0031]
4 (a), 4 (b), 5 (a), and 5 (b) are diagrams for explaining the function and effect of this embodiment, and FIG. 9 (a) and FIG. This corresponds to FIGS. 9B, 10A, and 10B.
[0032]
As shown in FIG. 4A, the lamp 10 has an illuminance distribution in which the light intensity in the vicinity of the optical axis L is high, and the light intensity decreases with distance D from the optical axis L. Therefore, as shown in FIG. 4A and FIG. 4B, a light beam having a non-uniform intensity in the incident surface is incident on each small lens. In addition, in the small lens that exists in a point-symmetrical position with respect to the optical axis L of the light source, when the position of the optical axis L is used as a reference, the intensity distribution in the incident surface is reversed. About these points, it is the same as that of a prior art.
[0033]
However, in the present embodiment, in the first lens array 21A, the small lenses c that exist at positions that are point-symmetric with respect to the optical axis L of the light source. ₅ And d ₄ Or c ₄ And d ₅ The small lens c in which the light emitted from the second lens array 22A exists in a position geometrically corresponding to the small lens in the second lens array 22A. ₅ 'And d ₄ 'Or c ₄ 'And d ₅ When the light beams are incident so that their positions are switched with respect to each other, the respective partial light beams reach the liquid crystal panels 51R, 51G, and 51B as shown in FIG. For this reason, as shown in FIG. 5 (a), the light beam l is applied to the points A and B near the edge of the liquid crystal panel. ₁ ~ L ₆ , L ₁ '~ L ₆ 'Will be incident. Specifically, light having an angle and intensity as indicated by a solid line in FIG. 5B is incident on point A, and angle and intensity as indicated by a dotted line in FIG. Light is incident. Compared to the prior art, the light beam l ₃ And l ₄ , Ray l ₃ 'And l ₄ Thus, it can be seen that the difference between the light amount on the + θ side and the light amount on the −θ side is smaller than that in the past at both the point A and the point B.
[0034]
Therefore, even if there is an angle at which the contrast of the image of the liquid crystal panel 51 is highest on either the + θ side or the −θ side, the difference between the + θ side light amount and the −θ side light amount at the points A and B Therefore, the difference in contrast between the point A and the point B is hardly generated. For this reason, it is possible to reduce the uneven color of the projected image and improve the contrast.
[0035]
As described above, according to the present embodiment, in the first lens array 21 </ b> A, the small lens c existing in a point-symmetrical position with respect to the optical axis L of the light source. ₅ And d ₄ Or c ₄ And d ₅ Small lens c in which the light emitted from the second lens array 2 exists in a position geometrically corresponding to these small lenses in the second lens array 2 ₅ 'And d ₄ 'Or c ₄ 'And d ₅ In contrast, by making the incident light so that the positions thereof are interchanged with each other, it is possible to reduce the uneven color of the projected image and improve the contrast.
[0036]
In the present embodiment, the small lens c existing in a point-symmetrical position with respect to the optical axis L of the light source. ₅ And d ₄ And c ₄ And d ₅ The position of the light emitted from the light source is switched, but another small lens existing at a point-symmetrical position with respect to the optical axis L of the light source, for example, c ₃ And d ₆ , B ₃ And e ₆ , B ₄ And e ₅ The position of the light emitted from the light source may be switched. However, in order to obtain a higher effect, it is desirable to change the position of the light emitted from the small lens having the maximum light quantity near the center of the optical axis as in the present embodiment. In addition, only a pair of small lenses existing at points symmetrical with respect to the optical axis L of the light source (for example, c ₅ And d ₄ However, in order to obtain a higher effect, the position of the light is switched so as to surround the optical axis L as in the present embodiment. Is preferred.
[0037]
(Second Embodiment)
FIG. 6 is a diagram showing a lighting device and a projection display device according to the second embodiment using a simplified equivalent optical system, and FIG. 7A shows the first lens array 21B in the z direction. FIG. 7B is a diagram of the second lens array 22B viewed in the z direction. The center of the cross shape shown in FIGS. 7A and 7B means the position of the optical axis of each small lens. As shown in FIG. 7A, the first lens array 21B includes a small lens a having 8 rows and 6 columns in a two-dimensional manner. ₁ ~ A ₈ , B ₁ ~ B ₈ , C ₁ ~ C ₈ , D ₁ ~ D ₈ , E ₁ ~ E ₈ , F ₁ ~ F ₈ Are arranged. On the other hand, as shown in FIG. 7B, the second lens array 22B is also two-dimensionally arranged with a small lens a having 8 rows and 6 columns. ₁ '~ A ₈ ', B ₁ '~ B ₈ ', C ₁ '~ C ₈ ', D ₁ '~ D ₈ ', E ₁ '~ E ₈ ', F ₁ '~ F ₈ 'Is arranged. Each small lens a of the first lens array 1B ₁ ~ A ₈ , B ₁ ~ B ₈ , C ₁ ~ C ₈ , D ₁ ~ D ₈ , E ₁ ~ E ₈ , F ₁ ~ F ₈ The geometric arrangement of each lenslet a of the second lens array 22B is as follows. ₁ ~ A ₈ ', B ₁ '~ B ₈ ', C ₁ '~ C ₈ ', D ₁ '~ D ₈ ', E ₁ '~ E ₈ ', F ₁ '~ F ₈ Corresponds to each.
[0038]
In the second embodiment, each small lens a of the first lens array 21B. ₁ ~ A ₈ , B ₁ ~ B ₈ , C ₁ ~ C ₈ , D ₁ ~ D ₈ , E ₁ ~ E ₈ , F ₁ ~ F ₈ , Each small lens a of the second lens array 22B ₁ '~ A ₈ ', B ₁ '~ B ₈ ', C ₁ '~ C ₈ ', D ₁ '~ D ₈ ', E ₁ '~ E ₈ ', F ₁ '~ F ₈ 'Is composed of a lens in which the position of the optical axis coincides with the geometric center. Instead, as shown in FIG. 6, the small lens c of the first lens array 21B. ₄ , C ₅ Is provided with a substantially triangular prism 25c which changes the traveling direction of the light beam. ₄ , D ₅ A substantially triangular prism 25d that changes the light traveling direction is provided on the light incident surface. The small lens c of the second lens array 22B ₄ ', C ₅ Also on the light exit surface side of 'a substantially triangular prism 25c' that changes the traveling direction of the light beam is a small lens d. ₄ ', D ₅ A substantially three-column prism 25d 'that changes the traveling direction of the light beam is also provided on the light emitting surface side of'.
[0039]
In the present embodiment, the small lens c of the first lens array 21B is thus obtained. ₄ , C ₅ Small lens d ₄ , D ₅ Are provided with substantially three columnar prisms 25d and 25d that change the traveling direction of the light beam, respectively, so that the small microlenses c of the first lens array 21B are provided. ₄ , C ₅ , D ₄ , D ₅ The emitted light beams are respectively small lenses d of the second lens array 22B. ₄ ', D ₅ ', C ₄ ', C ₅ 'Become incident on. That is, in the first lens array 21B, the small lenses c existing at positions symmetrical with respect to the boundary line Ly of the small lens including the optical axis L of the light source. ₄ And d ₄ The emitted light is a small lens c existing in a position geometrically corresponding to these small lenses in the second lens array 22B. ₄ 'And d ₄ 'Are incident so that their positions are interchanged with each other. Further, in the first lens array 21B, the small lenses c existing at positions symmetrical with respect to the boundary line Ly of the small lens including the optical axis L of the light source. ₅ And d ₅ The light emitted from the small lens c existing in a position geometrically corresponding to these small lenses in the second lens array 22. ₅ 'And d ₅ 'Are incident so that their positions are interchanged with each other. The light beams emitted from the other small lenses of the first lens array 21B are incident on the corresponding small lenses of the second lens array 22B.
[0040]
Therefore, as in the case of the first embodiment, the difference between the light amount on the + θ side and the light amount on the −θ side can be made smaller than that in the past at both the point A and the point B. Even if there is an angle at which the contrast of the image of the liquid crystal panel 51 is highest in any one of these, a difference in contrast between the point A and the point B is hardly caused. For this reason, it is possible to reduce the uneven color of the projected image and improve the contrast.
[0041]
Note that the effect of reducing color unevenness and improving contrast is slightly inferior in the present embodiment in which light rays are exchanged in line symmetry, compared to the first embodiment in which light rays are exchanged in point symmetry. However, in the present embodiment, the shape of the small lenses of the first lens array 21B and the second lens array 22B may be the same as the conventional one, which is advantageous over the first embodiment in that the fabrication is easy. is there.
[0042]
Further, in this embodiment, the light positions are switched for two pairs of small lenses that exist symmetrically with respect to the boundary line Ly of the small lens including the optical axis L of the light source. You may perform only about a lens. However, in order to obtain a higher effect, it is preferable to change the positions of the light for a plurality of pairs of lenses so as to surround the optical axis L as in the present embodiment.
[0043]
In the present embodiment, the substantially triangular prisms 25c, 25d, 25c ′, and 25d ′ that change the traveling direction of the light beam are provided so as to be integrated with the lens arrays 21B and 22B. It may be arranged.
[0044]
Furthermore, in this embodiment, the prisms 25c and 25d are used as the light source and the small lens c of the first lens array 21B. ₄ , C ₅ , D ₄ , D ₅ Is provided in the optical path between and the small lens c ₄ , C ₅ , D ₄ , D ₅ And the small lens c of the second lens array 21B ₄ ', C ₅ ', D ₄ ', D ₅ It may be provided between 'and. Similarly, the small lenses c of the second lens array are also provided at the positions where the prisms 25c ′ and 25d ′ are provided. ₄ ', C ₅ ', D ₄ ', D ₅ Small lens c, not limited to the light exit side ₄ ', C ₅ ', D ₄ ', D ₅ 'And the small lens c of the first lens array 21B ₄ , C ₅ , D ₄ , D ₅ You may make it provide between.
[0045]
(Modification of the second embodiment)
In the second embodiment, the small lens c that exists at positions symmetrical to each other with respect to the boundary line Ly of the small lens including the optical axis L of the light source. ₄ And d ₄ Or c ₅ And d ₅ The small lens c existing in the position corresponding to these small lenses in the second lens array 22B in the second lens array 22B. ₄ 'And d ₄ 'Or c ₅ 'And d ₅ However, the reference boundary line may be Lx. That is, the small lens c existing in a symmetrical position with respect to the boundary line Lx of the small lens including the optical axis L of the light source. ₄ And c ₅ Or d ₄ And d ₅ Small lens c existing in a position geometrically corresponding to these small lenses in the second lens array 22B. ₄ 'And c ₅ 'Or d ₄ 'And d ₅ In contrast, they may be incident so that their positions are interchanged. Even if it does in this way, it is possible to acquire the effect similar to 2nd Embodiment.
[0046]
In the second embodiment, in order to change the position of the light, the substantially triangular prisms 25c and 25d that change the traveling direction of the light beam are used. Instead of using such a prism, an eccentric lens is used. It may be used. In this case, the small lens of the second lens array 22B into which the replaced light is incident is also configured by an eccentric lens.
[0047]
Furthermore, in the second embodiment, when the mirror 24 as shown in FIG. 1 is arranged in the optical path between the first lens array 21B and the second lens array 22B, the traveling direction of the light beam Instead of the substantially triangular prisms 25c and 25d that change the angle, a step portion for changing the traveling direction of the light may be provided on the mirror 24 at a position where the light emitted from the predetermined small lens is reflected. .
[0048]
(Deformation)
The present invention is not limited to the embodiment described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention.
[0049]
In the above-described embodiment, an example of a projection display device using a transmissive liquid crystal panel has been described. However, the present invention can be similarly applied to a projection display device using a reflective liquid crystal panel.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing a first embodiment of an illumination device and a projection display device according to the present invention.
FIG. 2 is a diagram showing the illumination device and the projection display device according to the first embodiment using a simplified equivalent optical system.
FIG. 3 is a diagram illustrating an extracted lens array of the illumination device and the projection display device according to the first embodiment, and FIG. 3A is a diagram of the first lens array 21A viewed in the z direction. FIG. 3B is a diagram of the second lens array 22A viewed in the z direction.
FIG. 4 is a diagram for explaining the operational effects of the present embodiment.
FIG. 5 is a diagram for explaining the effect of the present embodiment.
FIG. 6 is a schematic view showing a second embodiment of the projection display apparatus according to the present invention.
FIG. 7 is a diagram showing an extracted lens array of the illumination device and the projection display device according to the second embodiment, and FIG. 7A is a diagram of the first lens array 21B viewed in the z direction. FIG. 7B is a diagram of the second lens array 22B viewed in the z direction.
FIG. 8 is a diagram illustrating an example of a conventional projection display device.
FIG. 9 is a diagram for explaining a problem of a uniform illumination optical system of a conventional projection display device.
FIG. 10 is a diagram illustrating a problem of a uniform illumination optical system of a conventional projection display device.
[Explanation of symbols]
1 Lighting device
2 Projection display device
10 Light source
11 Light source lamp
12 Curved reflector
20, 20A, 20B Uniform illumination optical system
21 First lens array
22 Second lens array
23 condenser lens
24 mirror
25 Prism
40 color separation optical system
41 Blue-green reflective dichroic mirror
42 Blue reflective dichroic mirror
43 Reflector
50 Light modulator (light valve)
51R, 51G, 51B LCD panel
60 color synthesis optical system
70 Projection optical system
71 Projection lens
90 Relay lens system
S screen

Claims (9)

Illumination comprising: a light source; a first lens array that divides the light emitted from the light source into a plurality of partial light beams; and a second lens array disposed on the light emission side of the first lens array. A device,
The first lens array has a plurality of small lenses arranged two-dimensionally,
The second lens array has a plurality of small lenses arranged two-dimensionally,
Of the small lenses constituting the first lens array, the light emitted from at least one pair of first small lenses present at point symmetry with respect to the optical axis of the light source is the second lens. An illuminating device comprising: a pair of second small lenses corresponding to the pair of first small lenses among the small lenses constituting the array so as to be interchanged with each other. The lighting device according to claim 1.
The pair of first small lenses and the pair of second small lenses are configured by decentering lenses. The lighting device according to claim 1 or 2,
The pair of first small lenses are small lenses having the largest amount of incident light. Illumination comprising: a light source; a first lens array that divides the light emitted from the light source into a plurality of partial light beams; and a second lens array disposed on the light emission side of the first lens array. A device,
The first lens array has a plurality of small lenses arranged two-dimensionally,
The second lens array has a plurality of small lenses arranged two-dimensionally,
Of the small lenses constituting the first lens array, light emitted from at least a pair of first small lenses present at positions symmetrical with respect to a boundary line of the small lens including the optical axis of the light source Are incident on the pair of second small lenses corresponding to the pair of first small lenses among the small lenses constituting the second lens array so that their positions are interchanged with each other. A lighting device. The lighting device according to claim 4.
In the optical path between the light source and the pair of first small lenses, a prism that changes the optical path is disposed,
A prism that changes the optical path is disposed in the optical path between the pair of first small lenses and the pair of second small lenses or on the light emission side of the pair of second small lenses. A lighting device. The lighting device according to claim 4.
A prism that changes the optical path is disposed in the optical path between the pair of first small lenses and the pair of second small lenses,
A prism that changes the optical path is disposed in the optical path between the pair of first small lenses and the pair of second small lenses or on the light emission side of the pair of second small lenses. A lighting device. The lighting device according to claim 4.
The pair of first small lenses and the pair of second small lenses are configured by decentering lenses. The illumination device according to any one of claims 4 to 7, wherein the pair of first small lenses are small lenses having the largest amount of incident light. apparatus. A lighting device according to any one of claims 1 to 6,
Color separation means for separating light from the illumination device into light beams of three primary colors;
A light modulation means for light-modulating the light flux of each color separated by the color separation means in accordance with image information;
Color synthesizing means for synthesizing the modulated light flux modulated by the light modulating means;
Projection means for enlarging and projecting the combined luminous flux synthesized by the color synthesis means;
A projection display device comprising:

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