JPH10111486A - Display device, liquid crystal panel for display device, and projection type display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive display device having high using efficiency of a light beam incident on a pixel aperture part, the uniform illuminance distribution of a light beam incident on a display panel, a small divergent angle of the incident beam, and a proper incident light beam made incident on each pixel. SOLUTION: In the display device making an irradiation light beam from a light source 110 incident on a display panel on which pixels are arranged through an image forming element array 117, projecting a transmitted light beam whose light intensity is controlled on an image display means and performing the image display, a light beam distributing means 113 for dividing/ distributing the irradiating beam to the image forming element array is provided between the light source and the image forming element array. A lens array composed of plural lenses or an ellipsoidal reflector composed of two and more different spheroids is used for the light beam distributing means 113.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device, and more particularly to a projection type display device using a liquid crystal display panel.

[0002]

2. Description of the Related Art In recent years, a projection type liquid crystal display device has attracted attention as a display device for displaying a large screen. As a projection type liquid crystal display device, a type in which a two-dimensional pattern of transmission / non-transmission is formed on a liquid crystal panel by using a laser beam, and a device of an electrically transmission / non-transmission using a thin film transistor or the like as a switching element. There is a type in which a dimensional pattern is formed on a liquid crystal panel. In particular, a liquid crystal display device using a liquid crystal panel which electrically forms a display pattern can display moving images and is expected to be used for a large-screen television.

[0003] Of the projection type liquid crystal devices using a display panel that operates as a light valve such as a liquid crystal panel, when focusing attention on a color display device, it is roughly classified into a three-panel type liquid crystal display device and a single-panel type liquid crystal display device. You. As shown in FIG. 40, the three-panel liquid crystal display device separates light of a light source into three primary colors by a dichroic mirror or the like, forms intensity distributions of the separated light by a liquid crystal panel, and returns them to a dichroic mirror or the like. Means that a color image is obtained by compositing. On the other hand, a single-panel type liquid crystal display device is shown in FIG.
As shown in 2, a color display is realized by using a single display panel, which requires only one display panel as compared with a three-panel type, and is considered to be easy to reduce cost.

In a projection type display device using a matrix transmission control type display panel represented by a liquid crystal panel, the area occupied by a pixel, which is one unit of a matrix forming an image, on a display surface is considered. The transmission area that actually contributes to the display is usually quite small. This is because most of the wiring for obtaining the driving voltage or current necessary for operating the pixel, the thin film transistor as a switch element, etc. are opaque, and the accurate transmittance control at the boundary between pixels is performed. Is difficult, so that the effective transmission area must be limited. The portion of the transmission area that contributes to the display, that is, the opening of the pixel is referred to as a pixel opening.

[0005] Usually, the irradiation light to the display panel is incident with almost uniform intensity in pixel units, but the light incident on portions other than the pixel openings is blocked. Therefore, an optical imaging element corresponding to the arrangement of the pixels is arranged on the irradiation light incident side of the pixel opening to form an illuminance distribution correlated with the pixel opening, and the ratio of transmitted light is improved by projecting light. 2. Description of the Related Art A technique for improving the light use efficiency of a display device is known. Usually, as an imaging element arranged on the irradiation light incident side of a pixel, a lens in which minute lenses are arranged in an array is used,
This is called a microlens array.

FIG. 40 is an explanatory diagram showing an optical configuration of a three-panel projection display device using a microlens array.

A parabolic reflector 4011 having an opening on the light irradiation side is disposed around a metal halide lamp 4010 as a light source for generating irradiation light. A filter 4012 for blocking ultraviolet rays is provided.

The first and second dichroic mirrors 4013 and 4014 for separating the irradiation light into three primary colors are provided on the filter 4012 side on which irradiation light is irradiated via the filter 4012.
A first mirror 4015 disposed at an angle of about 45 degrees with respect to 12 and reflecting the red light reflected by the first dichroic mirror 4013 is disposed substantially parallel to the first dichroic mirror 4013. I have. First mirror 40
A first liquid crystal module driven by an electric signal related to a red image, that is, a red image signal, is provided at a position where the red light reflected by 15 is irradiated. The first liquid crystal module includes an incident side polarizing plate 4031 and a micro lens array 40 in order from the incident side of the video signal to the outgoing side.
32, a liquid crystal panel 4033 driven by a red video signal,
The output side polarizing plate 4034 and the field lens 4035 are provided.

[0009] Of the irradiation light transmitted through the first dichroic mirror 4013, green light is reflected by the second dichroic mirror 4014, and blue light is transmitted through the second dichroic mirror 4014. A second liquid crystal module including a liquid crystal panel 4043 driven by an electric signal related to a green image, that is, a green image signal, is provided at a position where the green light is irradiated, and a first liquid crystal module and a second liquid crystal are provided. On the emission side of the module, a third dichroic mirror 4017 is arranged at an angle of about 45 degrees with respect to the liquid crystal panels 4033 and 4043 of the first liquid crystal module and the second liquid crystal module. The light emitted from the first liquid crystal module passes through the third dichroic mirror 4017, and the light emitted from the second liquid crystal module is reflected by the third dichroic mirror 4017.

At a position where the blue light transmitted through the second dichroic mirror 4014 is irradiated, a third liquid crystal module having a liquid crystal panel 4053 driven by a blue video signal is provided. On the emission side of the liquid crystal module, a second mirror 4016 is disposed at an angle of about 45 degrees with respect to the liquid crystal panel 4053.

At a position where the light from the third dichroic mirror 4017 and the blue light from the second mirror 4016 are irradiated, a fourth dichroic is disposed substantially in parallel with the third dichroic mirror 4017 and the second mirror 4016. A mirror 4018 is provided, light from the third dichroic mirror 4017 passes through the fourth dichroic mirror 4018, and blue light from the second mirror 4016 is reflected by the fourth dichroic mirror 4018,
Here, the images of the three primary colors emitted from each liquid crystal module are combined. The synthesized image is projected by the projection lens 4019.
Is projected on the screen 4020 via the.

Next, the operation of the three-panel projection display device using the microlens array shown in FIG. 40 will be described.

The light of the metal halide lamp 4010 is converted into substantially parallel light by a parabolic reflector 4011, and becomes white light from which unnecessary invisible light is removed by a filter 4012 that blocks infrared rays and ultraviolet rays, and is converted into white light by a first dichroic mirror 4013. Incident. The first dichroic mirror 4013 has a characteristic of reflecting only red light, and the reflected red light is reflected by the first mirror 4015.
Is reflected by the incident side polarizing plate 40 of the first liquid crystal module.
It is incident on 31. The red light converted to red polarization by the incident side polarizing plate 4031 enters the microlens array 4032 and is driven by a red image signal.
Incident on. The pixels of the liquid crystal panel 4033 operate in a 90-degree twisted nematic mode, rotate the incident polarized light by 90 degrees during the brightest display, and transmit without rotating the polarized light during the dark display.

The microlenses on the microlens array 4032 are provided at positions corresponding to the pixel openings of the liquid crystal panel 4033, and have a function of condensing incident light on the pixel openings.

FIG. 41 is an explanatory diagram schematically showing a state in which the microlenses on the microlens array converge the incident light on the pixel openings of the liquid crystal panel. Light incident on the microlens on the microlens array 4101 is transmitted through the light incident side substrate 4102, condensed on the opening of the pixel 4103, and emitted through the light emitting side substrate 4104.

Returning to FIG. 40, the micro lens array 4
The red light transmitted through the pixel opening of the liquid crystal panel 4033 with high efficiency by the function of No. 032 functions as a filter whose transmittance changes in accordance with the state of rotation of the liquid crystal panel 4033 by the output side polarizing plate 4034, so that the light intensity is high. And the field lens 4035 and the projection lens 4019
Is magnified and projected on the screen 4020.

Field lens 4035 and projection lens 4
019, there are third and fourth dichroic mirrors 4017 and 4018. The third dichroic mirror 4017 transmits red light and reflects green light, and the fourth dichroic mirror 4018. Has a characteristic of transmitting red light and green light and reflecting only blue light, so that red light is not affected.

On the other hand, the first dichroic mirror 401
3 are separated by a second dichroic mirror 4014 and, like red light, a liquid crystal panel 4043 driven by a green video signal and a liquid crystal panel 4053 driven by a blue video signal. Thus, a green image and a blue image whose light intensities are controlled are synthesized by the third and fourth dichroic mirrors 4017 and 4018 and the second mirror 4016 and enlarged and projected.

There are various types of display devices that realize color display with only one display panel. As a typical example, each of the display devices is provided with a pixel driven by an intensity signal of each of the three primary colors. A display device of a type in which a corresponding color filter is formed, and an imaging element array disposed immediately before the display panel, that is, on the light incident side, and irradiating light rays of three primary colors at different angles, respectively, to thereby emit light of each of the three primary colors 2. Description of the Related Art There is a display device that realizes color display by making light of a color corresponding to each of pixels driven by a color intensity signal incident thereon.

When comparing these two types of display devices,
In a display device using a color filter, the color filter absorbs or reflects two of the three colors to cause a loss in an optical signal, whereas a display device using an imaging element array causes such a loss. Therefore, it is expected that the display device can realize a brighter display than a display device using a color filter.

FIG. 42 is an explanatory diagram showing the optical configuration of a single-panel color display device using an imaging element array. FIG.
In the example of the configuration shown in the above, a microlens array is used as an imaging element array, and a plurality of dichroics arranged at different angles in order to separate light rays to be applied to the imaging element into three colors according to angles. A mirror is used.

An elliptical reflector 4211 having an opening on the light irradiation side is provided around a metal halide lamp 4210 which is a light source for generating irradiation light, and a parallel light is provided on the opening side of the elliptical reflector 4211. A conical lens 4212 for obtaining is provided. Conical lens 4212
On the light exit side, a stop 4 for adjusting the angle distribution of light is provided.
Reference numeral 213 is provided so as to cover the periphery of the conical lens 4212.

A filter 42 for blocking infrared rays and ultraviolet rays is provided on the light exit side of the conical lens 4212 and the aperture 4213.
14, a condenser lens 4215, and a color separation mirror 4216 composed of three dichroic mirrors are arranged in this order. The color separation mirror 4216 is used to separate incident light into light of three primary colors having different reflection angles from each other.
The dichroic mirrors are arranged at a small angle to each other. 3 by color separation mirror 4216
At the position where the light separated into the primary colors is reflected, the incident-side polarizing plate 4217 and the microlens array 421 arranged in this order are arranged.
8. A liquid crystal module including a liquid crystal panel 4219 and an output side polarizing plate 4220 is provided, and a field lens 4221 and a projection lens 4222 are provided on the output side of the liquid crystal module. Furthermore, in the actual configuration,
A screen on which an image projected by the projection lens 4222 is formed is used, but such components are omitted in the drawing. The optical configuration of the single-panel color display device using the imaging element array has been described above.

The operation of the single-panel color display device using the imaging element array shown in FIG. 42 will be described below.

Light from a metal halide lamp 4210 is condensed by a conical lens 411 by a spheroidal reflector 4211.
The light is condensed at a position immediately before the surface on the light incident side of 212. The conical lens 4212 concentrates the emission angle of the collected light on the optical axis side of the emitted light so that parallel light can be obtained more easily. The reason why the exit angle of the light emitted from the conical lens 4212 is limited by the stop 4213 is that the stop 4213
The angular distribution of light obtained on the exit side of the condenser lens 4215 is determined by the area of the light exit portion and the focal length of the condenser lens 4215, so that a predetermined angular distribution described later is obtained.

The light emitted from the aperture 4213 is incident on a condenser lens 4215 after unnecessary invisible light is removed by an infrared and ultraviolet cutoff filter 4214.

When the condenser lens 4215 is made of a normal glass spherical lens, it becomes a thick lens having a large spherical aberration. Therefore, a Fresnel lens which is reduced in weight and reduced in aberration is used.

The light converted into substantially parallel light by the condenser lens 4215 is incident on a color separation mirror 4216 composed of three dichroic mirrors. Color separation mirror 4
The characteristics of the three dichroic mirrors constituting the 216 are as follows. When the three dichroic mirrors are dichroic mirrors 4216R, 4216G, and 4216B, the dichroic mirror 4216R reflects only red light of visible light, and similarly, the dichroic mirror 4
216G reflects green light, and dichroic mirror 4216B reflects only blue light.

FIG. 43 is a graph showing an example of characteristics of three dichroic mirrors constituting the color separation mirror 4216. Curves B, G, and R in the graph show the characteristics of the reflectance of the dichroic mirrors 4216R, 4216G, and 4216B with respect to the wavelength of light, respectively. That is, as described above, the dichroic mirror 4216R reflects only the red light out of the visible light, and similarly, the dichroic mirror 4216G reflects the green light and the dichroic mirror 4216.
B reflects only blue light.

FIG. 44 is an explanatory diagram schematically showing angles of arrangement of three dichroic mirrors constituting the color separation mirror 4216. As described above, the color separation mirror 42
Reference numeral 16 denotes three dichroic mirrors 421 for separating incident light into light of three primary colors having mutually different reflection angles.
6R, 4216G, and 4216B are arranged so as to form a small angle with each other. Specifically, a dichroic mirror 4216B located at the center of the three dichroic mirrors 4216R, 4216G, and 4216B is arranged so as to form an angle of 45 degrees with respect to the optical axis of the incident light, and the dichroic mirrors 4216R, 4216G
Are arranged at an angle of about 2.3 degrees with respect to the dichroic mirror 4216B. Three dichroic mirrors 4216R, 4216G, 4216
By arranging B in this manner, incident light is separated into optical signals of three primary colors having different angles in the horizontal direction of the liquid crystal panel 4219.

As described above, the light that has been angle-separated into the three primary colors is incident on the incident-side polarizing plate 42 of the liquid crystal module in FIG.
After being polarized by the microlens array 421
7 and the liquid crystal panel 4218.

FIG. 45 is an explanatory view schematically showing the relationship between the microlens array and the liquid crystal panel. The state of light incident on one microlens of the microlens array 4501 is shown by the microlens array 4501 and the liquid crystal panel. 2 is a partially enlarged horizontal section. The liquid crystal panel includes a light incident side substrate 4502, a pixel portion 4503, and a light emission side substrate 4504.

The three primary colors of light R, G, and B (light R is red light, light G) are angle-separated to one imaging element (microlens) of a microlens array 4501 that is an imaging element array.
Is green light and light B is blue light). Due to the angle difference given by this angle separation, the light R, G, B of the three primary colors
Are separately incident on openings provided for respective colors in one pixel of a pixel portion 4503 of the liquid crystal panel via a light incident side substrate 4502 constituting the liquid crystal panel.

At this time, the thickness t and the refractive index n of the light incident side substrate 4502, the pixel pitch Ppixel, and the imaging element pitch P with respect to the angle difference Δθ between the incident lights of the three primary colors R, G, and B.
The following relationship is established between lenses.

[0035]

(Equation 2) The light thus color-separated passes through the openings of the corresponding colors, and is emitted from the light emission side substrate 4504.
2, a color image is formed by transmission through the exit-side polarizing plate 4220, and the color image is enlarged and projected on a screen by the field lens 4221 and the projection lens 4222, so that a large-screen display can be realized.

Incidentally, one of the problems of the projection type display device is that uneven display is likely to occur. The cause of this problem is that when the light from the lamp of the light source is condensed on the liquid crystal panel, the light protruding outside the display unit of the liquid crystal panel is reduced, and the central part is extended to the end of the display unit. This is because it is difficult to irradiate light to make it brighter.

FIG. 46 is an explanatory diagram schematically showing the incident illuminance of the liquid crystal display panel of the projection display device. When a normal light source is used, the illuminance gradually decreases toward the periphery of the illumination. Therefore, only a portion having a high degree of uniformity of the illuminance is applied to the display panel as shown in FIG. If used, light is wasted at the periphery and efficiency is low.
On the other hand, if it is attempted to reduce the light leaking out of the display panel as in the case shown in FIG. 46B, the periphery of the display area becomes very dark, and the uneven brightness or uneven illuminance increases. In addition, the fact that the shape of the display unit is usually rectangular is also one of the factors that make it difficult to condense light.

As means for solving the above-mentioned problems of illumination efficiency and illuminance unevenness, an illumination device using a set of lens arrays has been proposed and used.

FIG. 47 is a schematic configuration diagram of an illumination device using one set of lens arrays. This illuminating device causes illumination light to enter the first lens array 4701 and converts the incident light to the first lens array 4701.
Divided into the number of lenses in the lens array 4701
The light emitted from each lens in the first lens array 4701 is made incident on the corresponding lens in the second lens array 4702, and the light emitted from each lens in the second lens array 4702 is displayed on a display panel such as a liquid crystal panel. 4703.

The shape of each lens of the first lens array 4701 is made similar to the shape of the display surface of the liquid crystal panel 4703, and the focal length of the second lens array 4702 is set to the shape of each lens of the first lens array 4701. By setting the shape so that it is projected on the surface of the display panel 4703 with substantially the same size as the display panel 4703, uniform and efficient illumination can be realized over the entire liquid crystal display surface.

FIG. 48 shows an example of a display device including an illumination device using the two lens arrays.

The light of the lamp 4801 is reflected by the parabolic reflector 480.
2, the light is condensed on the first lens array 4804a via the infrared / ultraviolet cut filter 4803. The first lens array 4804a divides light into a shape similar to the display panel and focuses the light on the second lens array 4804b. The second lens array 4804b projects light from individual lenses in the first lens array 4804a to the display panel 4807. In front of the display panel 4807, a condenser lens 4805 and a polarizing plate 4806 are provided.
The light from the second lens array 4804b is converted into substantially parallel light, and is polarized and enters the liquid crystal panel 4807.
The light whose polarization state is modulated by the liquid crystal panel 4807 is converted into light intensity modulation by the polarizing plate 4808, and is projected by the field lens 4809 and the projection lens 4810.

[0043]

However, the light source using the lens array has a problem that it is difficult to apply the light source to a display panel using an imaging element array. The reason is that by using a lens array, the angle of light incident on the display panel is dispersed in a large number, and the angular distribution of light from the light source becomes very large.

FIG. 49 shows the angular distribution of the emitted light in the ordinary illumination optical system, and FIG. 50 shows the angular distribution of the emitted light in the illumination device using the 3 × 5 lens array, as the inclination angle θ of the incident angle with respect to the display panel. FIG. 4 is an explanatory diagram displayed on a plane having an azimuth angle φ. In the case of the ordinary illumination optical system shown in FIG. 49, the light spreads around the portion of the display panel in the vertical incidence state and forms a cluster. On the other hand, in the case of the illuminating device using the lens array shown in FIG. 50, the light emitted from each lens in the lens array is separated on an angle, so that in the case of the same light amount, The overall distribution range becomes wider.

When light is condensed on the opening of the pixel by an imaging element such as a microlens arranged near the pixel of the display panel, the image forming element and the pixel opening depend on the size of the angle distribution of the incident light. Distance is limited.

FIG. 51 is an explanatory view schematically showing the maximum distance between the imaging element and the pixel opening when the range of the angle distribution of the incident light of the incident light is small and large.

In the case where the incident angle θi shown in FIG. 51A is small, the distance t between the imaging element and the pixel opening can be made long, so that the divergence angle θou by the imaging element is obtained.
t also becomes smaller. On the other hand, when the incident angle θi shown in FIG. 51B is large, the distance t between the imaging element and the pixel opening needs to be short, and therefore, the divergence angle θout by the imaging element is required. Also increases. That is, in the case of an illumination device using a lens array, there are problems that the imaging element and the pixel opening need to be close to each other and that the divergence angle θout becomes very large.

This problem also occurs in the case where the aim is to improve the transmittance of the display panel by the image forming element, or in the case where the image forming element is used to separate colors according to the incident angle. This makes it difficult to apply a light source using a lens array to a projection display device.

Further, it is more difficult to combine a liquid crystal panel of a single-panel type color display device of a type that separates colors by an incident angle with a light source using a lens array.

FIG. 52 is an explanatory view showing, on a plane, the angular distribution after angle separation into three colors in the case of a normal illumination optical system, and FIG. 53 shows three colors in the case of an illumination device using a lens array. FIG. 9 is an explanatory diagram showing an angle distribution after angle separation on a plane. Comparing FIG. 52 with FIG. 53, the illumination device using the lens array shown in FIG. 53 has a much larger angular distribution than the ordinary illumination optical system shown in FIG. It can be seen that it has.

As described above, the light obtained by adding the divergence angle of the image forming element to this angular distribution is incident on the display panel, and is projected on the display screen by the projection lens.
When light having a large divergence angle is incident on the display panel, surface reflection on the display panel or the like increases, and the possibility that the amount of light decreases is increased. Further, for example, when the display panel is a liquid crystal panel, there is a property that the display characteristics change depending on the angle of light of the liquid crystal panel (viewing angle characteristics), and using light having a large divergence angle adversely affects display performance.

Further, when an image of the display panel is projected on a display screen by a projection lens in a state where light having a large divergence angle is incident on the display panel, a very large F number is required to project light having a large divergence angle. A small projection lens is required. A projection lens having a small F number is usually expensive and heavy, and it is difficult to improve the resolution and reduce the distortion in terms of design. This results in an increase in the size and weight of the projection display device, an increase in cost, and a decrease in performance.

Further, in the case of an optical system using two sets of lens arrays, two optical elements having complicated shapes are required.
There is a drawback that the optical path length of the optical system becomes longer and the set size of the projection display device increases. In addition, when a plurality of optical elements are provided, the number of reflection surfaces increases, the optical loss increases, and the efficiency decreases.

The present invention has been made in view of the above-mentioned problems, and has as its object to improve the efficiency of use of incident light to a pixel opening, to provide a uniform illuminance distribution of incident light to a display panel, A display device with a small divergence angle, a good display performance due to appropriate incident light being incident on each pixel, a short optical path length, a small and inexpensive display device, a liquid crystal panel for a display device, and a projection type display device. To provide.

[0055]

According to the present invention, irradiation light from a light source is transmitted through an imaging element array in which a plurality of imaging elements for imaging the irradiation light are formed. In a display device in which a pixel which is a unit for controlling the intensity is incident on a display panel arranged two-dimensionally, and the transmitted light whose intensity of the irradiation light is controlled is projected on a video display unit to display a video, A light distribution unit is provided between the light source and the imaging element array to divide the irradiation light into the imaging element array and distribute the light.

The light distribution means has a uniform illuminance distribution of the light applied to the liquid crystal panel and has good display performance. Moreover, the optical path length is short, small and inexpensive.

As the light distribution means, a lens array composed of a plurality of lenses, or an elliptical surface composed of two or more different spheroids, for dividing and condensing irradiation light for each of the plurality of lenses. With the reflector, 2 of each spheroid
The one in which the position of one of the focal points substantially coincides with the light source position is used.

[0058]

Embodiments of a display device according to the present invention will be described below with reference to the drawings.

First, the principle by which the display device according to the present invention can be realized will be described. The incident light having a discrete angular distribution determined by the positional relationship between the lamp serving as the light source, the lens array, and the imaging element array is set as follows.

(1) In the case of a display device that does not use color angle separation, the angle distribution of incident light is reduced by one imaging element in an imaging element array provided on the incident surface side of the display panel. The interval of the discrete irradiance distribution generated in the pixel opening of the display panel based on the interval in which the pixel is formed, or in at least one direction in the plane where the pixel opening on the display panel is formed or Make it an integral multiple of that.

(2) Alternatively, the discrete irradiance distributions generated in the pixel openings of the display panel are aligned in one direction.

(3) On the other hand, in the case of a display device of the type using angle separation of colors, the interval of the irradiance distribution of light of the same color is determined by the interval at which pixels corresponding to the color are formed,
It is made to match in at least one direction within a plane where a pixel opening on a display panel is formed, or to make it an integral multiple thereof.

(4) Further, the discrete irradiance distribution of the same color is aligned in one direction different from (not parallel to) the direction in which pixels of different colors are arranged.

(5) In any case, in a direction other than the above-mentioned coincident direction in the plane where the pixel openings are formed on the display panel, the discrete illuminance distribution is different from the arrangement interval of the pixels. If the interval is not an integral multiple,
The refractive power in the other direction of the imaging element array is made weaker than the refractive power in the direction in which the intervals are matched. Specifically, the following conditions are set.

FIG. 54 shows the distance between the lens array of the lens array and the distance between the lens and the condenser lens, the distance between the pixels on the display panel, and the image forming element in the illumination device using the lens array and the display panel using the image forming element array. It is explanatory drawing which represented typically the relationship with the distance between an array and a pixel opening.

In this display device, a lens array 5401 used for an illumination device, a condenser lens 5402 arranged at a distance L from the lens array 5401, and a light incident through the condenser lens 5402 are separated by a color angle separation optical system 5403. Element array 5404 composed of microlenses, and an imaging element array 5
It also has a schematic configuration including a pixel opening 5406 on the display panel on which an optical medium 5405 having a thickness t is sandwiched after 404 and light incident through the imaging element array 5404 is incident thereon. .

The lens array 5401 is a lens corresponding to the lens array 4702 in FIG. 47. For example, when the parallelism of light incident on the lens array 4701 in FIG. 47 is sufficiently high, this lens array becomes unnecessary. That is, the light from the lens array on the light source side, that is, the individual lenses of the lens array 4701 in FIG. Therefore, in this case, the lens array 5401 is actually unnecessary in FIG. 54, and in the following description,
The lens array 5401 is a plurality of light source images formed by the first lens array closer to the light source.

Assuming that the horizontal distance between the individual lenses formed in the lens array 5401 is Pi, the relative refractive index of the optical medium is n, and the horizontal pixel distance of the liquid crystal panel is Pp, Pp / (n · t) ) = Pi / L (Equation 2) holds. Actually, since a design error, a measurement error, and the like occur, it is not always necessary to exactly match Expression 2. The actual arrangement conditions may be slightly different from the above-mentioned ideal conditions due to a demand for reduction of aberration or the like.

The position of the pixel opening is at most
Even if the lens 401 is shifted by one lens, the incident light does not deviate from the position of each pixel opening.
The number M between the lenses in the lateral direction of the lens 401 can be given a width that allows a shift of 1 at both ends, and the following condition is obtained.

[0070]

(Equation 3) Here, if two quantities of P and P0 are defined as P = Pp / (nt) (Equation 4) P0 = Pi / L (Equation 5), then Equation 2 can be written as P = P0 (Equation 6). .

As shown in FIG. 55, this P0 is (M
Consider a state where the width is the width of M gaps formed by +1) lenses.

In this figure, considering the minimum range and the maximum range with respect to P0 at both ends, when the center width is reduced by P0 as shown in FIG.

(Equation 4) And if the center width is increased by P0,

(Equation 5) It is considered that in this range, the center position becomes the reference P0
It can be seen that the width of P fits at both ends in the case of width.
Therefore, it is understood that the condition is satisfied even in the range of Expression 3.

Alternatively, the problem can be solved by arranging the lens arrays 5401 only in the vertical direction (in the plane of the paper) and arranging them in a line.

The microlens of the imaging element array 5404 is different from the aspheric lens whose focal length is sufficiently long with respect to the distance t to the pixel opening in the section perpendicular to the plane of FIG. Good. Further, a cylindrical lens having no refracting power in a cross section perpendicular to the paper surface of FIG. 54 may be used. In addition, in the case of a display device of a type that does not use color angle separation by a two-dimensional distribution of discrete irradiances generated in the pixel openings 5406 of the display panel,
The position of each micro lens of the imaging element array 5404 is
It is even better to match the position where the pixel is formed.
Similarly, in the case of a display device using the angle separation of colors,
The position of each micro lens of the imaging element array 5405 is
It is even better to match the position where pixels corresponding to the same color are formed.

More specifically, in addition to the above-described conditions for making the interval of the irradiance distribution of light coincide with the pixel interval in one direction, the arrangement of the pixel openings on the display panel and the lens array 54
It is preferable that the arrangement of the lenses in the image No. 01 be similar. If distortion can occur due to the aberration of the condenser lens 5402, the arrangement interval of the lens array 5401 in the direction in which the distortion is inversely corrected so that the angle distribution of light incident on the imaging element array has a more accurate cycle. Is desirably corrected.

When the ratio of the vertical and horizontal intervals of the arrangement of the pixel openings is different from the vertical and horizontal ratio of the display screen, light from each lens of another lens array disposed between the lens array 5401 and the light source is In order to make the light incident on the lens array 5401 having different arrangement intervals and to form the incident light through each lens in the other lens array near the display panel and the imaging element array by the lens array 5401, another lens is used. It is necessary that the entire array and the entire lens array 5401 have different refractive powers in the vertical and horizontal directions, respectively.

Here, the magnitude of the refractive power required for another lens array and the lens array 5401 will be examined. The magnitude of the refractive power is defined as positive for light collection and negative for divergence.
When the magnitude is expressed including the sign, the refractive power of the other lens array and the refractive power of the lens array 5401 are respectively set as follows.

The display screen of the display panel has the shape of the ratio of vertical VF to horizontal HF, and the arrangement interval of the pixel openings is vertical VP and horizontal HP.
If the shape of the lens in the other lens array is vertical V
Since the ratio of the shape of the ratio of F to the width of the horizontal HF and the arrangement interval of each lens of the lens array 3001 are the vertical VP and the horizontal HP, if VF / HF <VP / HP, the refractive power of the other lens array as a whole is The lens array 5 is smaller in the vertical direction than in the horizontal direction.
The refractive power of the whole 401 needs to be larger in the vertical direction than in the horizontal direction.

On the other hand, if VF / HF> VP / HP, the refractive power of the other lens array as a whole is greater in the vertical direction than in the horizontal direction, and the lens array 5
The refractive power of the entire 401 needs to be smaller in the vertical direction than in the horizontal direction.

As described above, when the position of each microlens of the imaging element array 5404 and the distribution of irradiance are made to match, each microlens of the imaging element array 5404 has a different refractive power for each direction. Not only can an aspherical lens having the following is applicable, but also a spherical lens whose refractive power matches in all directions can be applied. Further, a stop may be provided on the exit surface of the lens array 5401. For example, when setting is made so that light from the center of each lens of the lens array 5401 passes through the pixel opening, a condition may be such that light at the boundary between the lenses of the lens array 5401 cannot pass through the pixel opening. Many,
This is because the light from the boundary may be absorbed by the display panel, which may cause inconvenience such as heat generation.

In the case of a display device of a type that performs color display by angle separation, light from a certain portion of the lens in the lens array 5401 has an angle distribution larger than the separation angle of angle separation. May interfere. For example, in a case where three apertures corresponding to three primary colors are provided in a pixel, the color separation occurs when light of a certain color enters a pixel aperture adjacent to the pixel aperture corresponding to the color. However, the condition varies depending on the width of the pixel opening. The minimum necessary condition under which the disturbance of color separation does not occur is that the width of the angle distribution of the incident light for one color is equal to or less than the width of the aperture of two pixels. FIG. 57 is an explanatory diagram schematically showing conditions of incident light for preventing occurrence of disturbance of color separation. When the pixel aperture corresponding to each color is very small, as shown in FIG. 57, no color mixing occurs when the width of the angular distribution of incident light for one color falls within the width of about two pixel apertures. . This condition is satisfied by the lens array 54
This is a condition corresponding to limiting the width of the lens on the exit surface of No. 01 to ピ ッ チ of the pitch.

When the stop is arranged near the lens array 5401 so as to satisfy this condition, if the exit width is within the width of two pixel openings when each pixel is provided with N openings. Assuming that the width of the stop is Ws with respect to the horizontal interval Pi between the individual lenses formed in the lens array 5401,

[0083]

(Equation 6) It suffices to satisfy the conditions

As another method for eliminating the above-mentioned drawback of the optical system using the two lens arrays, light from a light source is condensed using a plurality of elliptical reflecting mirrors as light distribution means.
It has been proposed to synthesize this. That is, by arranging one of the focal points of the plurality of spheroidal reflecting mirrors in the vicinity of the light emitting portion of the light source and at least one of the other focal points on the condensing side at a different position, the light from the light source is It can be divided into a plurality of secondary light sources, and a uniform display similar to the case where two sets of lens arrays are used can be realized. Especially,
By arranging a lens array in which a plurality of lenses corresponding to individual secondary light source positions are arranged in the vicinity of a secondary light source formed by a plurality of spheroidal reflecting mirrors, each lens in the lens array emits light of the secondary light source. Since each light is condensed, illumination efficiency can be improved.

Hereinafter, each embodiment of the display device according to the present invention will be specifically described. (First Embodiment) FIG. 1 is an explanatory view showing an optical configuration of a display device according to a first embodiment of the present invention. The present invention is applied to a single-panel color display device using an imaging element array. This is a first example to which the configuration described above is applied. A microlens array is used as an image forming element array, and a plurality of dichroic mirrors arranged at different angles are used to separate light rays irradiated to the image forming element into three colors according to angles.

An elliptical reflector 111 having an opening on the light irradiation side is provided around a metal halide lamp 110 which is a light source for generating irradiation light. The opening of the elliptical reflector 111 receives infrared rays and ultraviolet rays. A filter 112 for blocking and a lens array 113 are provided. The metal halide lamp 110 is an elliptical reflector 11
1 is disposed at a substantially focal position. At a position where the irradiation light from each lens of the lens array 113 is condensed, a diaphragm 121 for adjusting the angle distribution of the light and blocking light between the lenses in the horizontal direction is provided. A condenser lens 11 is provided on the light exit side of the diaphragm 121.
5, 3 dichroic mirrors 116R, 116B,
A color separation mirror 116 composed of 116G is arranged in order. The color separation mirror 116 is disposed so that three dichroic mirrors 116R, 116B, and 116G form a small angle with each other in order to separate incident light into light of three primary colors having different reflection angles. I have.

At the position where the light separated into the three primary colors by the color separation mirror 116 is reflected, an incident side polarizing plate 122, a micro lens array 117, a liquid crystal panel 118, and an outgoing side polarizing plate 123 are sequentially arranged. A liquid crystal module is provided, and a field lens 119 and a projection lens 120 are provided on the emission side of the liquid crystal module. Further, in an actual configuration, a screen on which an image projected by the projection lens 120 is formed is used.
The components are omitted in the drawings.

Next, the operation in this configuration will be described. The light of the metal halide lamp 110 disposed at a substantially focal position of the elliptical reflector 111 is converged by the elliptical reflector 111 toward another focal position of the ellipsoid of which the elliptical reflector 111 forms a part. Lens array 11 which is transmitted through a filter 112 for blocking light and is closer to the metal halide lamp 110 than the other focal points.
3 is incident.

FIG. 2 shows the structure of the lens array 113. FIG. 2 (a) is a front view of the lens array 113 viewed from a direction perpendicular to the optical axis. FIG. 2 (b) is a view of FIG. Line AB
FIG.

The shape of each lens in the lens array 113 is a square having an aspect ratio of 9:16, which is similar to the display surface of the liquid crystal panel 118. As can be seen from the cross-sectional shape shown in FIG. 2B, the lens array 113 changes the traveling direction of the light converging toward another focal position of the ellipsoid forming part of the elliptical reflector 111 for each lens. Then, the convergence of the light is weakened by moving it outward, and the converging position is moved from the other focal position.

At the position where light converges, the lens array 11
A plurality of lamp images equal to the number of three lenses are formed, and an illuminance distribution is generated. At this time, it is necessary to design the lens array 113 so that the interval between the lamp image and the adjacent lamp image is substantially equal, and the overlapping portion between the lamp images is minimized. In the present embodiment, the interval between the lamp images is 18.5 mm.

FIG. 3 is a front view of the diaphragm 121. The diaphragm 121 functions to block light between the lamp images generated by the first lens array 113 and separate the lamp images.

In this embodiment, the horizontal separation is important, the vertical separation is unnecessary, and the vertical separation is
In order to increase the transmitted light even a little, it is desirable not to shield between the lamp images. Therefore, the aperture has a vertical slit shape.

From the formula 4, the width of the slit is 12.3 mm.
(= 18.5 × 2/3) or less. In the example of the first embodiment, the width is 5.3 mm in consideration of the width of the pixel opening and the assembly margin.

The condenser lens 115 has a focal length of 150
mm Fresnel convex lens, and the first lens array 1
Since the interval between the lamp images 13 is 18.5 mm, the light emitted from the condenser lens 115 is separated into three angles with an angle difference of about every 7 degrees. Light emitted from the condenser lens 115 is transmitted to a color separation mirror 116.
Is incident on.

As shown in FIG. 1, the color separation mirror 116 has three dichroic mirrors 116R, 116G,
116B. The reflection characteristics of the three dichroic mirrors 116R, 116G, 116B are shown in FIG.
This is the same as the reflection characteristics of the three dichroic mirrors shown in FIG. Curves B, G, and R in the graph of FIG. 43 are dichroic mirrors 116R, 116G, and 116B, respectively.
The dichroic mirror 116R reflects only red light out of visible light, and the dichroic mirror 116G similarly emits green light,
The dichroic mirror 116B reflects only blue light.

FIG. 4 is a view showing a third embodiment of the color separation mirror 116.
Dichroic mirrors 116R, 116G, 116
It is explanatory drawing which represented the angle of arrangement | positioning of B typically.

Referring to FIG. 4, the color separation mirror 116
Has three dichroic mirrors 116R and 116R to separate incident light into light of three primary colors having different reflection angles from each other.
116G and 116B are arranged so as to form a small angle with each other. In the first embodiment, three dichroic mirrors 116R, 116G, 116B are used.
A dichroic mirror 116B located at the center of the lens is arranged so as to form an angle of 45 degrees with the optical axis of the incident light,
On both sides thereof, dichroic mirrors 116R and 116G are respectively about 1.1 with respect to dichroic mirror 116B.
They are arranged at an angle of two degrees.

The three dichroic mirrors 116R, 1
By arranging 16G and 116B in this way,
The incident white light is transmitted in the horizontal direction of the liquid crystal panel 118.
The light signal is separated into light signals of primary colors that are angle-separated every three degrees and reflected.

As described above, the light that has been angle-separated into the three primary colors is incident on the incident-side polarizing plate 122 of the liquid crystal module in FIG.
After being polarized by the microlens array 117 and the liquid crystal panel 118,
3. After passing through the field lens 119, the projection lens 12
0 causes the image to be projected on the display screen.

The state of incidence of light from the micro lens array 117 to the liquid crystal panel 118 is such that the light source and the micro lens array according to the present invention allow only predetermined primary color light to enter predetermined pixels of the liquid crystal panel. I have.

FIG. 5 is an enlarged view of a part of the micro lens array 117 and the liquid crystal panel 118. FIG.
Is a microlens array 501 having a shape formed by arranging a plurality of cylindrical lenses in parallel with no gap as shown in FIG.
The interval Plens of the array is set equal to the interval Ppixel of the array of the pixel openings 502 that includes three primary colors as one set.

In the first embodiment, as shown in FIG. 5, the pixel apertures sharing the three primary colors are arranged in parallel, and as will be described later, the lateral microlens array is arranged. Are the angles for three colors. That is, in this example, the horizontal separation angle of the microlens array is set to three times the separation angle of the dichroic mirror as a color separation element, so that light of the same color transmitted through a plurality of microlenses to a predetermined pixel. Is incident.

Therefore, even if white light is angularly separated by the lens array, light of a predetermined color can be made incident on a predetermined pixel by using the angle separating means.

In the vertical direction, which is a direction orthogonal to the horizontal direction, which is the angle separation direction of the color, the focal length of the microlens is lengthened or no image is formed, so that the vertical direction of the lens array is reduced. Alleviates the vertical illuminance distribution generated by the angular separation of the directions, prevents light from concentrating on the light-shielding portion that partitions the vertical direction of the display panel, and
The angle of the emitted light in the vertical direction by the microlens can be reduced.

In the example shown in FIG. 5, the micro lens 501 is a cylindrical lens so as to prevent vertical image formation. Here, one cylindrical surface lens is formed as an imaging element for three pixel apertures. In FIG. 5, since the vertical cross sections of the image forming elements are continuous, it can be seen that one image forming element corresponds to a row of three pixel apertures. Not something to take.

FIG. 6 is a cross-sectional view in the horizontal direction of a component between the incident-side polarizer and the output-side polarizer of the liquid crystal module. FIG. 6 (a) shows the relevant portion of the display device according to the present invention. FIG. 6B shows the relevant portion of the conventional display device. Reference numerals 601 and 604 denote a microlens array, and reference numeral 60 denotes a microlens array.
Reference numerals 2 and 605 denote pixel openings, and reference numerals 603 and 606 denote light incident side substrates of the liquid crystal panel, respectively.

In the display device according to the present invention shown in FIG. 6A, the light incident on the microlens array 601 is as follows.
The lens array 113 and the color separation mirror 116 in FIG.
As a result, nine light beams are incident at intervals of 1.2 degrees.

In the first embodiment, the distance between the microlens array 601 and the surface 602 of the pixel opening of the liquid crystal element is 1.12 mm. Of the 1.12 mm, 1.10 mm is a glass substrate (Corning 7059) on which a counter electrode constituting a liquid crystal cell is formed, and the remaining 0.02 mm is an acrylic adhesive. Their combined refractive index is approximately 1.52 and the microlens 601
After transmission, the separation angle of each light becomes about 1.5 degrees according to Snell's law, and each of the nine incident lights enters the pixel opening 702 at an interval of 31 μm.

Therefore, as shown in FIG. 6A, light incident on one micro lens of the micro lens array 601 is incident on three columns of pixels. When viewed from the pixel side, light from three rows of microlenses enters.

On the other hand, in the conventional display device shown in FIG. 6B, a single incident light is converted into three lights every 2.3 degrees by the dichroic mirror, and is transmitted through the microlens array 604 and the light incident side substrate 606. Incident on the pixel opening 605. Since the dispersion angle of the light incident on the pixel opening 605 is large, the distance between the microlens array 604 and the surface 605 of the pixel opening of the liquid crystal element has to be shortened to 0.57 mm. Must be thick enough to fit within this distance. The light incident on one micro lens of the micro lens array 604 is 1
Only the light from the microlenses in one row is incident on the pixels in the row, and even when viewed from the pixel side.

As described above, in the display device according to the present invention, the light separated into the three primary colors on the liquid crystal panel enters the pixels of the liquid crystal panel driven by the video signals indicating the brightness of each of the three primary colors. Thus, color display can be realized.

The effect of the present invention was evaluated by comparing the above-described display device according to the first embodiment of the present invention with the conventional single-panel display device shown in FIG.

Regarding the uniformity of the display, the projection screen is divided into nine parts, the illuminance at the center of each part is measured, and the average value of the nine measured values and the maximum value among the nine measured values are measured. And the maximum / average magnitude, which is the ratio of That is,
The closer this value is to 1, the better the display uniformity. In the conventional single-panel display device, this value was 1.6, whereas in the display device according to the first embodiment of the present invention, a favorable value of 1.4 was obtained.

Regarding the brightness of the display, the luminous flux emitted from the projection lens was obtained based on the average of the nine points of the illuminance and the display area as the evaluation value. In contrast to the conventional single-panel display device of 180 lumens, the display device according to the first embodiment of the present invention has a brightness of 200 lumens, which is about 10% higher. This is because, apart from the effect of reducing the divergence angle by splitting the incident light from the light source, the fact that the focal length of the microlens has been increased has made it possible to reduce the spherical aberration and the like of the microlens. It is thought that it has become.

The structure of the present invention has a remarkable effect also in the manufacturing process in the following points. FIG. 6B shows the configuration of the liquid crystal panel portion of the conventional display device. In the conventional display device, the thickness of the light incident side substrate 606 of the liquid crystal panel is about 0.54 mm. On the other hand, the display device according to the first embodiment of the present invention has a thickness of 1.1 m, which is usually used as a substrate of a liquid crystal panel.
m glass substrates could be used. That is, in the process of assembling the liquid crystal cell of the conventional single-panel display device, it is more difficult to make the thickness of the liquid crystal layer of the liquid crystal cell uniform because the thickness of the opposing substrate is reduced. Since it was necessary to change the condition settings and the like, there was also a problem with mass production. On the other hand, in the display device according to the first embodiment of the present invention, the ordinary liquid crystal cell assembling process can be used, so that it can be mass-produced with the conventional manufacturing apparatus as it is, and the equipment cost can be reduced. Can be achieved. (Second Embodiment) FIG. 7 is an explanatory diagram showing an optical configuration of a display device according to a second embodiment of the present invention. FIG.
Is almost the same as the configuration shown in FIG. 1, and the reference numerals of the corresponding components are 100s in FIG. 1 and 7 in FIG.
Other than the 00s are the same.

This embodiment is different from the first embodiment in that the second lens array 714 is
It is the point inserted before 1.

FIG. 8 is a front view of the lens array 714. The second lens array 714 has a function of efficiently condensing the light from the first lens array 713 to the micro lens array 717, so that brightness and display uniformity can be further improved.

The lenses of the second lens array 714 are shown in FIG.
The front view is shown in FIG. 2, and a small convex lens is shown in FIG.
Are arranged in the same three rows as the lens array 713 shown in FIG. The focal length of each convex lens is set near the position of a condenser lens 715 described later.
3 is set to form an image. That is, the focal length f2 of the lens in the second lens array 714 in FIG.
Is based on the relationship between image and focus

[0120]

(Equation 7) Becomes Here, L1 is the distance between the first and second lens arrays, L2 is the distance between the second lens array 714 and the condenser lens 715, and N is the first lens array 713.
This is a ratio of the size of each lens inside to the size of the display surface of the liquid crystal panel 718. In the example of the first embodiment,
The value of N is about 4, and the second lens array 714
Has a horizontal pitch of 18.5 mm, as shown in FIG.

A stop 721 disposed immediately after the second lens array 714 is provided.
Reference numeral 1 is the same as the diaphragm 121 in FIG. 3, and a description thereof will be omitted.

The condenser lens 715 is a Fresnel convex lens having a focal length of 150 mm and a focal point substantially at the center of the second lens array 714. The distance in the horizontal direction between the lenses of the second lens array 714 is 18.5 m.
m, the light emitted from the condenser lens 715 is separated into three angles with an angle difference of about every 7 degrees. The light emitted from the condenser lens 715 is incident on the color separation mirror 716. (Third Embodiment) FIG. 9 is an explanatory view showing an optical configuration of a display device according to a third embodiment of the present invention. The present invention is applied to a single-panel color display device using an imaging element array. An example in which the configuration of FIG.

As in the case of the first embodiment, a microlens array is used as an image forming element array, and arranged at different angles in order to separate light rays to be applied to the image forming element into three colors according to angles. And a plurality of dichroic mirrors.

A parabolic reflector 911 having an opening on the light irradiation side is disposed around a metal halide lamp 910 which is a light source for generating irradiation light. A filter 912 for blocking infrared rays and ultraviolet rays and a first lens array 913 are provided. The second lens array 914 is located at a position where the irradiation light from each lens of the first lens array 913 is collected.
Are arranged. A stop 921 for adjusting the angular distribution of light is disposed on the light emission side of the second lens array 914 so as to block light between the lenses in the lateral direction of each lens of the second lens array 914. Have been.

Second lens array 914 and aperture 921
A condenser lens 915 and a color separation mirror 916 composed of three dichroic mirrors are arranged in this order on the light exit side. The color separation mirror 916 is disposed so that three dichroic mirrors form a small angle with each other in order to separate incident light into light of three primary colors having different reflection angles.

At the position where the light separated into the three primary colors by the color separation mirror 916 is reflected, an entrance side polarizing plate 922, a micro lens array 917, a liquid crystal panel 918, and an exit side polarizing plate 923 are sequentially arranged. A liquid crystal module is provided, and a field lens 919 and a projection lens 920 are provided on the video signal emission side of the liquid crystal module. Furthermore, in an actual configuration, the projection lens 9
A screen on which the image projected by 20 is formed is used, but the components are omitted in the drawing.

The difference between the display device according to the third embodiment and the display device according to the second embodiment is that a rotating parabolic mirror (parabolic reflector) is used as a reflection plate for light emitted from a light source. 911 is used, how the first and second lens arrays 913 and 914 are given the refractive power as a whole, and the condenser lens 915 is not a Fresnel lens but an ordinary convex single lens. That was the point.

By using a rotating parabolic mirror (parabolic reflector) 911 as the reflecting plate, the light incident on the first lens array 913 is almost parallel light, and the characteristics of the convex lens as a whole are given. First lens array 9
By using the light source 13, the light is condensed for each lens element in the first lens array 913 and simultaneously condensed as a whole, so that the second lens array 914 smaller than the first lens array 913. Light enters. Second
Has a concave lens characteristic as a whole, and converts incident light into gentle divergent light. Further, each lens in the first lens array 913 and each lens in the second lens array 914 have a one-to-one correspondence, and a liquid crystal panel 918 is connected through a condenser lens 915.
Each lens in the first lens array 913 is formed on the upper side.

As for the luminance distribution of the display device according to the third embodiment, a favorable value was obtained in which the value of the maximum value / average value of 9 points was 1.2. Further, the brightness of the display is about 1.1 in comparison with the conventional single-panel display device shown in FIG.
Doubled to 200 lumens. The brightness of this value is the same as that of the display device according to the first embodiment of the present invention,
It is considered that the improvement can be made to some extent by further optimizing the lens shape of the first lens array 813. (Fourth Embodiment) FIG. 10 is an explanatory view showing an optical configuration of a display device according to a fourth embodiment of the present invention. In this embodiment, an angle separating element and a color image forming element for each color are shown. A sheet in which a phase control type diffraction grating is formed for each pixel is used as a child.

An elliptical reflector 1002 having an opening on the light irradiation side is provided around a metal halide lamp 1001 which is a light source for generating irradiation light. The opening of the elliptical reflector 1002 receives infrared rays and ultraviolet rays. Filter 1003 for blocking and first lens array 1004
Are arranged. The metal halide lamp 1001 is disposed so as to be located substantially at the focal point of the elliptical reflector 1002. The second lens array 1 is located at a position where the irradiation light from each lens of the first lens array 1004 is focused.
007 is provided and the second lens array 1005
An aperture 1 for adjusting the angular distribution of light is provided on the light exit side of
Reference numeral 006 is provided so as to block light between the lenses in the lateral direction of each lens of the second lens array 1005.

Second lens array 1005 and aperture 10
A condenser lens 1007 is provided on the light emitting side of the light emitting element 06. With this condenser lens 1007, the light emitted from each lens of the second lens array 1005 becomes parallel light. However, the condenser lens 1007 is the first
Unlike the second embodiment, the focal position is set at a position different from that of the second lens array 1005. That is, by shifting the center of the condenser lens 1007 in a direction perpendicular to the optical axis of the spheroidal reflector (elliptical reflector 1002), rays emitted from the lenses in the second lens array 1005 are parallel to each other. Are arranged so as to be incident on the diffraction grating array element 1009 at an angle of about 40 degrees.

On the light exit side of the condenser lens 1007, a liquid crystal module including an incident side polarizer 1008, a diffraction grating array element 1009, a liquid crystal panel 1010, and an exit side polarizer 1011 arranged in order is provided. A field lens 1012 and a projection lens 1013 are provided on the video signal emission side of the module. Further, in an actual configuration, a screen on which an image projected by the projection lens 1013 is formed is used, but the components are omitted in the drawing.

The incident-side polarizing plate 1008 is arranged at an angle at which the light emitted from the condenser lens 1007 enters substantially perpendicularly. This is because the degree of polarization of the polarizing plate is lower at oblique incidence, so that the contrast ratio is improved. The light emitted from the condenser lens 1007 is incident on the incident side polarizing plate 1008.
As a result, the light enters the diffraction grating array element 1009 as polarized light.

FIG. 11 is an explanatory diagram schematically showing a state in which incident light enters a pixel opening via a diffraction grating array element and a light incident side substrate. Reference numeral 1101 denotes a diffraction grating array element, reference numeral 1102 denotes a pixel opening, and reference numeral 1103 denotes a light incident substrate. In the third embodiment, the pixel interval between the pixel openings 1102 is 96 μm, the thickness of the light incident side substrate 1103 is 0.6 mm, and the angle difference between the incident light 1 and the incident light 2 is about 13 degrees. It is.

When the incident lights 1 and 2 are
When the light enters the pixel aperture 01, the light is split for each diffraction grating and radiated to the pixel opening. The split incident light from each diffraction grating is incident on two mutually adjacent pixel openings on the incident path.

FIG. 12 is an explanatory view schematically showing a grating pattern of the diffraction grating array element used in the fourth embodiment. This diffraction grating array element is a transmission-type phase diffraction grating, and has an image forming effect on incident light in the horizontal direction but has no effect in the vertical direction. Therefore, since the diffraction occurs only in the horizontal direction, the light intensity distribution on the pixel due to the vertical angle distribution does not occur. The pitch of the diffraction grating of this diffraction grating array element was 0.977 μm at the maximum part and 0.761 μm at the minimum part.

Regarding the luminance distribution in the display device according to the fourth embodiment, the maximum value / 9-point average value is 1.3.
A relatively good value of 5 was obtained. (Fifth Embodiment) FIG. 13 is an explanatory view showing an optical configuration of a display device according to a fifth embodiment of the present invention. The present invention is applied to a three-panel color display device using an imaging element array. This is an example in which the configuration of FIG.

A composite elliptical reflector 1311 having an opening on the light irradiation side is disposed around a metal halide lamp 1310 as a light source for generating irradiation light. Filter 1312 for blocking and first lens array 13
13 are provided. A second lens array 1314 is provided at a position where incident light via the filter 1312 and the first lens array 1313 is focused.

On the light emission side of the second lens array 1314, a first dichroic mirror 1315 for separating irradiation light into three primary colors is disposed at an angle of about 45 degrees with respect to the optical axis of the composite elliptical reflector 1311. You. The first dichroic mirror 1315 has a function of separating red light and other light, and reflects only red light of the irradiated light and transmits other light.

The first condenser lens 1318 is provided on the traveling path of the red reflected light reflected by the first dichroic mirror 1315, and the red light is irradiated through the first condenser lens 1318. At a position, a first mirror 1319 that reflects the red light is disposed substantially parallel to the first dichroic mirror 1315.

At a position where the red light reflected by the first mirror 1319 is irradiated, a first liquid crystal module for forming a red image is provided. The first liquid crystal module includes, in order from the incident side of the incident light to the exit side, the incident side polarizing plate 1.
331, micro lens array 1332, liquid crystal panel 1
334, output side polarizing plate 1335, field lens 13
36.

The second condenser lens 131 is placed on the traveling path of the light transmitted through the first dichroic mirror 1315.
6 is disposed, and the second condenser lens 1316 is provided.
The second dichroic mirror 1317 is located at a position where the light is irradiated through the first dichroic mirror 131.
5 are arranged substantially in parallel. The second dichroic mirror 1317 has a function of separating green light and blue light, and reflects the green light and transmits the blue light in the irradiated light.

A second liquid crystal module having a liquid crystal panel 1344 is provided at a position where the green light is irradiated, and a third liquid crystal module is provided on the light emitting side of the first liquid crystal module and the second liquid crystal module. A dichroic mirror 1320 is disposed at an angle of about 45 degrees with respect to the liquid crystal panels 1334 and 1344 of the first and second liquid crystal modules. Red light from the first liquid crystal module is transmitted through the third dichroic mirror 1320, and green light from the second liquid crystal module is transmitted through the third dichroic mirror 120.
Reflected by 320.

At a position where the blue light transmitted through the second dichroic mirror 1317 is irradiated, a third liquid crystal module having a liquid crystal panel 1354 for forming a blue image is provided. On the output side of the module, a second mirror 1321 is disposed at an angle of about 45 degrees with respect to the liquid crystal panel 1354.

The third dichroic mirror 1320 is located at a position where the irradiation light from the third dichroic mirror 1320 and the blue light from the second mirror 1321 are irradiated.
A fourth dichroic mirror 1322 is provided in parallel with the second mirror 1321, and irradiation light from the third dichroic mirror 1320 passes through the fourth dichroic mirror 1322 and is transmitted from the second mirror 1321. The blue light is reflected by the fourth dichroic mirror 1322, and the light of the three primary colors emitted from each liquid crystal module is synthesized again. The image of the synthesized light is projected on a screen via a projection lens 1323.

The display device according to the fifth embodiment is different from the display device shown in FIG.
The point different from the conventional three-panel projection display device shown in FIG. 0 is the components of the light source and the relationship between the microlens array and the liquid crystal panel.

First, the light source will be described. In the fifth embodiment, a compound elliptical reflector 1311 combining two types of spheroids is used as a reflecting mirror for collecting the light of the metal halide lamp 1310.

FIG. 14A is a front view of the composite elliptical reflector, and FIGS. 14B and 14C are cross-sectional views taken along lines CD and EF in FIG. 14A, respectively. FIG. 14 (a)
(B) As shown in (c), the composite elliptical reflector 1311 according to the fifth embodiment is a reflecting mirror combining two types of spheroidal surfaces 1401 and 1402.
The spheroidal surface 1401 and the spheroidal surface 1402 have substantially the same focal position, and by arranging the light emitting part of the lamp at one of the elliptical focal positions, it is possible to focus light at the other focal position. What is possible is the same as that of a normal reflecting mirror having one kind of spheroid. The difference from the ordinary reflecting mirror is that the eccentricity of the spheroid 1401 arranged in the horizontal direction perpendicular to the optical axis is larger than the eccentricity of the spheroid 1402 arranged in the vertical and vertical directions. The point that the cross section of the light exiting from and focusing on the focal point is wider than vertical. This is based on the principle disclosed in Japanese Patent Application Laid-Open No. 7-270789 (Japanese Patent Application No. 6-062396), and three or more types of spheroids can be used.

It is necessary that the focal positions of the spheroids constituting the composite elliptical reflector be accurately matched so as to be located within the range of the size of the light emitting portion of the lamp used as the light source. In this arrangement of the focal positions, the function of receiving and reflecting the light from the light source arranged at one focal position of the spheroid on the reflecting surface and condensing the light at the other focal position is simultaneously performed by the plural spheroids. Needed for. In the fifth embodiment, it is considered that the focal points coincide within a range of about ± 0.4 mm in consideration of the processing accuracy of the reflecting mirror and the like. The width in this range sufficiently satisfies the condition because the light emission length of the arc of the metal halide lamp used as the light source is about 3 mm.

FIG. 15A shows the first lens array 131.
15 is a sectional view taken along lines GH and IJ in FIG. 15A.

The first lens array provided at the opening of the composite elliptical reflector is composed of a horizontally long lens for a horizontally long display panel having an aspect ratio of 9:16.
3 and the whole is horizontally long.
However, the cross section of the incident light is also horizontally long, and the light utilization efficiency does not decrease due to such a shape. As shown in the cross-sectional views of FIGS. 15B and 15C, each lens constituting the first lens array is a concave lens, and the refractive power of the entire lens array is longer in the vertical direction. At the position where it is strongly negative (ie, small) and enters the second lens array, the light distribution is
It matches the arrangement of the lenses of the second lens array having an aspect ratio of 1: 1.

FIG. 16A shows the second lens array 13.
14 is a plan view, and FIGS. 16B and 16C show FIG.
FIG. 7 is a sectional view taken along lines KL and MN in FIG. FIG. 16 (a)
(B) As shown in (c), the second lens array is formed by forming circular convex lenses in a 3 × 3 arrangement, and has a substantially convex shape as a whole.

The display panel in the fifth embodiment is a liquid crystal panel in which the vertical and horizontal pixels are arranged at equal intervals, and the second lens array also has the same vertical and horizontal lens arrangement.

The refractive power of the second lens array as a whole is negatively weaker (that is, larger) in the vertical direction, and the first and second condenser lenses 1 in FIG.
At the time when the light passes through 318 and 1316 and reaches the microlens arrays 1332, 1342, and 1352, which are the imaging element arrays, the light intensity distribution coincides with the display area of the display panel.

Returning to FIG. 13, the micro lens array 1
The light transmitted through 332 is the liquid crystal panel 1 which is a display panel.
The light is condensed on the 333 pixel aperture. The same applies to other liquid crystal modules.

The lens forming interval of the second lens array 1314 is 14 mm, the distance of the light path between the second lens array and the first and second condenser lenses 1318 and 1316 is 176 mm, and the micro lens array 133 is provided.
The distance between the lens of No. 2 and the pixels of the liquid crystal panel 1333 is 60 μm, and the distance between the microlens array 1332 and the pixels of the liquid crystal panel 1333 is 1.15 mm, which satisfies the condition of Expression 3 above.

In the fifth embodiment, the total luminous flux 1
Using a 6,000 lumen metal halide lamp,
A luminous flux of 520 lumens from the projection lens could be achieved. In addition, as for the luminance distribution, a very good value of 1.13 (maximum value / 9-point average value) was obtained. (Sixth Embodiment) FIG. 17 is an explanatory diagram showing an optical configuration of a display device according to a sixth embodiment of the present invention.

Light from a metal halide lamp 1710 is reflected by an ellipsoidal reflector 1711, enters a first lens array 1713 via a filter 1712 for cutting infrared rays and ultraviolet rays, and is converged on a second lens array 1714. You. In the second lens array, the refracted light passes through the stop 1721 and the condenser lens 1.
715, through a color separation mirror 1716 composed of three dichroic mirrors, a polarizing plate 1722 on the incident side,
Micro lens array 1717, liquid crystal panel 1718,
The light enters the liquid crystal module formed of the polarizing plate 1723 on the emission side, and is projected through the field lens 1719 to the projection lens 1.
720.

The optical structure after the dichroic mirror 1716 in this embodiment is basically the same as that of the conventional display device shown in FIG. 41, but includes a first lens array 1713 and a second lens array 1714. And the second lens array 1714 is arranged in a line.

These points will be described with reference to FIGS. The first lens array 1713 is made up of four lenses as shown in FIG. 18, and each lens is arranged such that light from each lens is condensed on the second lens array 1714 shown in FIG. 19. The lens has an inclined surface.

That is, the light transmitted through the lens 1 is
Lens 2 at the focal point 2, lens 3 at the focal point 3,
The lenses 4 converge on the focal point 4 respectively. In the vicinity of each focal point, the second lens array 17 shown in FIG.
The light from the first lens array 1713 is corrected in the direction of the condenser lens 1715, and is efficiently guided to the dichroic mirror 1716.

FIG. 20 is an explanatory diagram showing a state of light collection between two lens arrays viewed from a direction different from that of FIG. 17 by 90 degrees. From FIGS. 25 and 28, the light from the second lens array 1714 is reflected by the dichroic mirror.
For directions that are angularly separated into three colors, illumination is performed from a very narrow area in one row. In directions different from this by 90 degrees, four lenses are arranged, and illumination is performed from a wide area. You can see that it is.

FIG. 21 shows a microlens array 1717 composed of a spherical convex lens 2101 and an opening 210.
FIG. 4 is an explanatory diagram showing the relationship with 2, wherein the distribution of irradiance formed from individual microlenses is narrow in the direction in which pixel openings of three colors are arranged, that is, in the horizontal direction of the display screen, and wide in the vertical direction.

This state is represented by one micro lens 2201.
FIG. 22 shows how the center of the three dichroic mirrors 1716 is illuminated by the dichroic mirror, and the blue light from the dichroic mirror is applied to the B pixel aperture 2202 in the horizontal direction shown in FIG. It can be seen that the light is condensed narrowly and condensed widely in the vertical direction shown in FIG.

As described above, the pixel opening 2102 shown in FIG.
Since the light use efficiency is significantly improved by matching the shape of the microlens array 2101 with the illumination by the microlens array 2101, it is possible to realize illumination that matches the relationship between the microlens array 1717 and the liquid crystal panel 1718.

In the luminance distribution according to the present embodiment, a favorable value was obtained in which the ratio of the maximum value to the average of nine points was 1.4.
Further, the brightness of the display was about 1.4 times 250 lumens as compared with the single-panel display device having the conventional configuration shown in FIG. (Seventh Embodiment) FIG. 23 shows an optical configuration diagram of a single-panel projection display apparatus according to a seventh embodiment of the present invention.
FIG. 24 shows a vertical cross section of the light source section of this embodiment, and FIG. 25 shows a horizontal cross section.

First, the overall configuration and operation will be described.

The light from the metal halide lamp 2301 is focused on the lens array 2304 by the concave reflecting mirror 2302. An infrared / ultraviolet cut filter 2303 is provided between the concave reflecting mirror 2302 and the lens array 2304.
Only visible light enters the lens array 2304.

The light incident on the lens array 2304 is bent in the direction of the condenser lens 2305 by the lens array, is collimated by the condenser lens 2305, is polarized by the polarizing plate 2306, and is polarized by the polarizing plate 2306.
07.

The liquid crystal panel 2307 is a 90-degree twisted nematic liquid crystal panel, and modulates the polarization state of emitted light according to a video signal. The light emitted from the liquid crystal panel 2307 is converted into light intensity modulation by the polarizing plate 2308, and the light is modulated by the condenser lens 2309 and the projection lens 231.
Projected by 0.

Next, the structure of the reflecting mirror, which is the main point in this embodiment, will be described. The reflecting mirror 2302 of the present embodiment has fifteen spheroidal reflecting mirrors 230201 to 230201.
23015. FIG. 26 shows this reflecting mirror viewed from the front. One of the focal points of each reflecting mirror is located at the light emitting portion of the lamp 2301, and the other focal point is located at the lens array 2
There is a vicinity of each corresponding lens position 304.

The display portion of the liquid crystal panel 2307 has a length-to-width ratio of 16: 9.
The solid angle when viewed from 104 is a rectangle of approximately 16: 9.

FIG. 24 is a view showing the state of reflection by the reflector and refraction by the lens array, including a vertical section passing through the center of the reflector of FIG.
0202, 230205, 230206, 23020
8, 230211 and 230214 correspond to the reflecting mirrors 2, 5, 6, 8, 11, and 14 shown in FIG. One of the focal points of these mirrors is at focal point A, the position where the lamp is located. The other focal points are respectively the focal points B
2, B5, B8, B11, and B14, and correspond to each lens in the lens array 2304. Also,
The angles at which the reflecting mirror is seen from each lens corresponding to the reflecting mirror in the lens array are almost equal.

FIG. 25 is a view showing the state of reflection by the reflector and refraction by the lens array, including a cross-section taken through the center of the reflector of FIG. 26. The reflection shown in FIG. The mirrors 230207, 230108 and 230209 are the reflecting mirrors 230207, 230108 and 2 shown in FIG.
30209.

As shown in FIGS. 24 and 25, the exit surface of the lens array 2304 has a concave lens shape.
The light condensed on the lens array part is condensed
It can be turned to the direction of 305.

As described above, in this embodiment, a plurality of 2
Since the liquid crystal panel is illuminated by the next light source, display with good uniformity is possible.

When this embodiment is compared with the conventional display device shown in FIG. 48, the present embodiment can be downsized and the number of parts is reduced, so that the whole display device can be reduced in size and weight. it can. Cost reduction can also be expected. (Eighth Embodiment) FIG. 27 shows an optical configuration of a projection display apparatus according to an eighth embodiment of the present invention.

The light from the lamp 2701 is converged in one direction by the concave reflecting mirror 2702 as in the seventh embodiment. As shown in the front view of FIG. 28, the concave reflecting mirror 2702 is composed of six parts, and light from each constituent part is transmitted to the lens array 2703 and the lens array 270.
The light is condensed at 4.

After passing through an aperture 2705 provided on the exit surface of the lens array 2704 and passing through an infrared / ultraviolet cut filter 2706, the condenser lens 270
7, the light becomes substantially parallel light.

This light is applied to a dichroic mirror 2708
The light is then angle-separated into three colors, passes through the polarizing plate 2709, becomes polarized light, and enters the microlens array 2710. Then, the light is modulated by passing through the liquid crystal panel 2711 and the polarizing plate 2712, and is projected by the field lens 2713 and the projection lens 2714.

FIG. 28 is a front view of the reflecting mirror 2702. Each reflecting mirror element is composed of six portions which are long in the vertical direction. Each reflecting mirror element is focused near the lamp 2801 and near the lens array 2804. Spheroid with.

The lamp 2 reflected by these reflecting mirrors
The light from 701 has its focal point in the vertical direction extended by the lens 2703 toward the condenser lens 2707 more than the lens array 2704.

Reflecting mirror 2 viewed from a cross section perpendicular to FIG.
FIG. 29 shows a state 702, a lens 2703, a lens array 2704, and light rays thereof. 27 and 29, it can be seen that in the direction of FIG. 27, the lens array 2703 does not affect the direction of the light beam, and focuses on the position of the lens array 2704 which is the focal position of the concave reflecting mirror 2702. On the other hand, in the direction of FIG.
The position where the light is condensed by 703 is more shifted by the condenser lens 2707
It works to shift in the direction.

The focus of the condenser lens 2707 is shown in FIG.
In the plane of FIG. 7, the lens array 270 is located at the position of the diaphragm 2705, and in the plane of FIG.
4 and the condenser lens 2707. Thereby, in the plane of FIG.
The width of the light beam exiting from 7 is wide and narrow in the plane of FIG.

With this operation, the liquid crystal panel 271 is formed despite the fact that each component of the concave mirror 2702 is vertically long.
Is similar to the aspect ratio of 9:16, which is the shape of the display section.

The stop 2705 provided on the exit surface of the lens array 2704 has a slit shape in the vertical direction as shown in FIG. 31, so that necessary parallelism of light can be obtained after passing through the condenser lens 2707. It is like.
FIG. 30 shows the shape of the lens array 2704 viewed from the front.

The dichroic mirror 2708 is similar to the one shown in FIG.
And three dichroic mirrors having the characteristics shown in FIG. 4 and arranged as shown in FIG. White light incident on the light at three different angles is angle-separated into three colors to become nine lights.

The relationship between this light, the micro lens 2710 and the liquid crystal panel 2711 is the same as that shown in FIG.

Light transmitted through each lens in the microlens array 2710 passes through a pixel opening driven by a video signal of each color, so that color display can be realized.

The effect of the present invention was evaluated by comparing the display device of this example with the conventional single-panel display device shown in FIG.

First, regarding the display uniformity, the projection screen is divided into nine parts, and the illuminance at the center of the divided part is measured.
Evaluation was made based on the maximum / average magnitude, which is the ratio of the average value of the measured values of the points to the maximum value among the measured values of the nine points.

In the conventional single-panel display device, this value was 1.6, but in this embodiment, a favorable value of 1.4 times was obtained.

The brightness of the display was calculated from the average of the nine points of the illuminance and the display area, and the luminous flux emitted from the projection lens was determined and evaluated. In contrast to the single-panel display device having the conventional configuration of 180 lumens, this embodiment has 220 lumens, which is about 1.2 times the brightness. (Ninth Embodiment) FIG. 32 shows an optical configuration diagram of a single-panel projection display apparatus according to a ninth embodiment of the present invention.

The light from the lamp 3201 is converged in one direction by the concave reflecting mirror 3202 as in the seventh embodiment. The concave reflecting mirror 3202 is composed of four parts as shown in the front view of FIG. 33 (a), and after the light from each of the constituent parts is reflected by the four plane mirrors 3203 for correcting the light beam direction. Are condensed on four conical lenses 3204, respectively.

After passing through an aperture 3205 provided on the exit surface of the conical lens 3212 and passing through an infrared / ultraviolet cut filter 3206, the condenser lens 320
7, the light becomes substantially parallel light.

This light is angle-separated into three colors by a dichroic mirror 3208, becomes polarized light through a polarizing plate 3209, and enters a microlens array 3210. Then, the light is modulated by passing through the liquid crystal panel 3211 and the polarizing plate 3212 and is projected by the field lens 3213 and the projection lens 3214.

FIG. 33B is a side view of the concave reflecting mirror 3202 used in the present embodiment, showing the shape and the position of the focal point. As can be seen from FIG. 33 (b), the concave reflecting mirror 3202 is constituted by four reflecting mirror sections each including four spheroids. One of the focal points of the reflecting mirrors 1, 2, 3, and 4 is a focal point A, and the other focal points are a focal point B1, a focal point B2, a focal point B3, and a focal point B4. It is in.

The lamp is located substantially at the position of the focal point A, and light from the lamp is condensed by the four reflecting mirror portions into four portions on one row which are arranged substantially vertically.

In FIG. 32, the focal points arranged in a line
On a plane perpendicular to the plane of the paper.

The four plane reflecting mirrors 3204 disposed slightly before the focal point pass through the conical lens 3204 which is disposed obliquely with respect to the optical axis passing through the center of the stop 3205 and the center of the condenser lens 3207. It functions to polarize the direction of the light beam so that the applied light overlaps the portion of the liquid crystal panel 3211. Since the lights from these four reflecting mirror portions are illuminated in an overlapping manner, the uniformity of the light intensity is improved.

The stop 3205 provided on the exit surface of each of the four conical lenses 3204 has a rectangular opening adapted to a state where these conical lenses are arranged in the vertical direction. The light that has passed through the aperture is converted into a condenser lens 3207.
After the transmission, the angular distribution is as shown in FIG.

FIG. 34 is a diagram showing an angle distribution with respect to the liquid crystal panel 3211 by an azimuth angle φ and a tilt angle θ.
It can be seen that four lights passing through the two conical lenses provide illumination having a large vertical angle distribution and a small horizontal angle distribution.

The dichroic mirror 3208 is similar to the one shown in FIG.
Are constituted by three dichroic mirrors having characteristics similar to those shown in FIG. 4 and arranged in the same manner as shown in FIG. The incident white light is angle-separated into three colors.

FIG. 35 shows the relationship between this light and the micro lens 3210 and the liquid crystal panel 3211.

The micro lens 3210 is a spherical convex lens, and the incident light shown in FIG.
An image is formed in the shape of the opening 211.
At this time, the angular distribution shown in FIG. 34 is angularly separated into three by the dichroic mirror 3208,
Light transmitted through each lens in the microlens array 3209 passes through a pixel opening driven by a video signal of each color, so that color display can be realized.

FIG. 36 shows the relationship between the pixel aperture and one microlens with respect to the light reflected by the dichroic mirror at the center of the dichroic mirror 3208 and incident on the microlens array 3209.

Reference numeral 3601 denotes a microlens, which condenses incident light into the pixel aperture 3602, but the blue light is narrower in the horizontal direction to the pixel aperture of B by the center dichroic mirror (FIG. 21A), and in the vertical direction. Widely (Fig. 21
(B)) Condensing.

As described above, by matching the shape of the pixel opening 3602 shown in FIG. 36 with the illumination by the microlens array, the light use efficiency is extremely improved.

The display device of the present embodiment was compared with the conventional single-panel display device shown in FIG. 42 to evaluate the effects of the present invention.

First, regarding the uniformity of display, the projection screen is divided into nine parts, and the illuminance at the center of the divided part is measured.
Evaluation was made based on the maximum / average magnitude, which is the ratio of the average value of the measured values of the points to the maximum value among the measured values of the nine points.

In the conventional single-panel display device, this value was 1.6, but in the present embodiment, a favorable value of 1.3 times was obtained.

Further, the brightness of the display was determined from the average of the nine points of the illuminance and the display area, and the luminous flux emitted from the projection lens was determined as an evaluation value. In contrast to the single-panel display device having the conventional configuration of 180 lumens, the brightness of the present embodiment is significantly improved to 280 lumens. (Tenth Embodiment) FIG. 37 shows an optical configuration diagram of a single-panel projection display apparatus according to a tenth embodiment of the present invention.

This embodiment is characterized in that the concave reflecting mirror 370 is provided.
2 is that a polarization beam splitter 3703 which is a polarization splitting element is arranged at a position where light is converged by 2.

The basic configuration and operation are the same as those of the ninth embodiment of the present invention. Here, the light source unit, which is a feature of the present embodiment, will be described.

As shown in FIG. 38, the concave reflecting mirror 3702 is composed of two parts, a reflecting mirror 1 and a reflecting mirror 2. Each of the concave reflecting mirror 3702 transfers the light of the lamp to two focal positions and a focal point B1.
At the focal point B2.

As shown in FIG. 39, a triangular prism 3911, a polarizing beam splitter 3912, a half-wave retarder 3913, convex lenses 3914A and 3914B, and a reflecting mirror 3215 are arranged near these two focal points, respectively. ing.

The triangular prism 3911 has a concave reflecting mirror 37.
It functions to bend the direction of the light from the direction 02 to the direction of the condenser lens 3707. The light whose direction has been changed by the triangular prism 3911 is separated into P-polarized light and S-polarized light by the polarization beam splitter 3912. The P-polarized light is transmitted through the polarization beam splitter 3912, the polarization direction is changed to the S-polarized direction by the phase difference plate 3913, and the convex lens 3914A
And exits in the direction of the condenser lens 3707.

The S-polarized light is reflected in the polarizing beam splitter, passes through the convex lens 3914B, and then is reflected by the reflecting mirror 391.
5 and exits in the direction of the condenser lens 3707.

As described above, the light from the lamp 3701 is
The light becomes S-polarized light, passes through a stop (omitted in FIG. 39), enters a condenser lens 3707, passes through an infrared / ultraviolet cut filter 3706, and is converted into substantially parallel light by the condenser lens 3707.

Another difference from the ninth embodiment is that the polarization rotator 3714 shown in FIG.
9 is arranged before the number 9.

The polarization rotator 3714 is necessary for aligning the polarization direction of the polarizing plate 3709 for selecting the polarization at 45 degrees to the liquid crystal panel with the polarization direction of the light from the dichroic mirror 3708. .

As a result, in the conventional projection type display device as shown in FIG. 41, approximately half of incident light is lost by the polarizing plate on the incident side, but it can be used for display without loss. Can be.

The effect of the present invention was evaluated by comparing the display device of the present embodiment with the conventional single-panel display device shown in FIG.

First, regarding the uniformity of the display, the projection screen is divided into nine parts, and the illuminance at the center of the division is measured.
Evaluation was made based on the maximum / average magnitude, which is the ratio of the average value of the measured values of the points to the maximum value among the measured values of the nine points.

In the conventional single-panel display device, this value was 1.6, but in the present embodiment, a favorable value of 1.5 times was obtained.

The brightness of the display was determined from the average of the nine points of the illuminance and the display area, and the luminous flux emitted from the projection lens was determined as an evaluation value. In contrast to the single-panel display device having the conventional configuration of 180 lumens, the brightness is greatly improved to 420 lumens in the present embodiment.

[0227]

According to the display device of the present invention, since the irradiation light from the light source is uniformly incident on each pixel of the liquid crystal panel using the light distribution means, the illuminance distribution of the incident light becomes uniform. As a result, it is possible to obtain good display quality with less display unevenness.

Further, according to the display device of the present invention,
Since a reflecting mirror including a plurality of reflecting mirrors having mutually different focal positions is used, the optical path length can be shortened, and a small and efficient display device can be provided.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an optical configuration of a display device according to a first embodiment of the present invention.

FIGS. 2A and 2B are a front view and a cross-sectional view of the first lens array according to the first embodiment, as viewed from a direction perpendicular to the optical axis.

FIG. 3 is a plan view of the stop according to the first embodiment.

FIG. 4 is an explanatory diagram schematically showing an arrangement angle of three dichroic mirrors constituting a color separation mirror according to the first embodiment.

FIG. 5 is a configuration diagram in which a part of the microlens array and the liquid crystal panel in the first embodiment is enlarged.

FIG. 6 is a cross-sectional view in the horizontal direction of a component between the incident-side polarizing plate and the output-side polarizing plate of the liquid crystal module.

FIG. 7 is an explanatory diagram showing an optical configuration of a display device according to a second embodiment of the present invention.

FIG. 8 is a plan view of a second lens array according to the second embodiment.

FIG. 9 is an explanatory diagram showing an optical configuration of a display device according to a third embodiment of the present invention.

FIG. 10 is an explanatory diagram showing an optical configuration of a display device according to a fourth embodiment of the present invention.

FIG. 11 is an explanatory diagram schematically showing a state in which incident light is incident on a pixel opening via a diffraction grating array element and a light incident side substrate in a fourth embodiment of the present invention.

FIG. 12 is an explanatory view schematically showing a grating pattern of a diffraction grating array element used in a fourth embodiment of the present invention.

FIG. 13 is an explanatory diagram showing an optical configuration of a display device according to a fifth embodiment of the present invention.

FIG. 14 is a front view and a cross-sectional view of a composite elliptical reflector according to a fifth embodiment of the present invention.

FIG. 15 is a front view and a cross-sectional view of a first lens array according to a fifth embodiment of the present invention.

FIG. 16 is a front view and a cross-sectional view of a second lens array according to a fifth embodiment of the present invention.

FIG. 17 is an explanatory diagram showing an optical configuration of a single-panel projection display device according to a sixth embodiment of the present invention.

FIG. 18 is a front view and a sectional view showing details of a first lens array according to a sixth embodiment of the present invention.

FIG. 19 is a front view and a sectional view showing details of a second lens array in a sixth embodiment of the present invention.

FIG. 20 is an explanatory diagram showing an optical configuration of a single-panel projection display device according to a sixth embodiment of the present invention viewed from a position different from that of FIG. 17 by 90 degrees.

FIG. 21 is an explanatory diagram schematically showing a relationship between a microlens array and a pixel aperture according to a sixth embodiment of the present invention.

FIG. 22 is an explanatory diagram schematically showing a relationship between one microlens and one pixel opening according to a sixth embodiment of the present invention.

FIG. 23 is a diagram illustrating an optical configuration of a projection type color liquid crystal display device according to a seventh embodiment of the present invention.

FIG. 24 is a diagram showing a vertical cross section around a reflecting mirror and a relationship between the reflecting mirror and its focal point in the projection type color liquid crystal display device according to the seventh embodiment of the present invention.

FIG. 25 is a diagram showing a horizontal cross section around a reflecting mirror and a relationship between the reflecting mirror and its focal point in a projection type color liquid crystal display device according to a seventh embodiment of the present invention.

FIG. 26 is a front view of a reflecting mirror in a projection type color liquid crystal display device according to a seventh embodiment of the present invention.

FIG. 27 is a diagram showing an optical configuration of a projection type color liquid crystal display device according to an eighth embodiment of the present invention.

FIG. 28 is a front view of a reflecting mirror in a projection type color liquid crystal display device according to an eighth embodiment of the present invention.

FIG. 29 is a diagram showing a vertical cross section around a reflecting mirror and a configuration of a lens array in a projection type color liquid crystal display device according to an eighth embodiment of the present invention.

FIG. 30 is a front view showing a lens array in a projection type color liquid crystal display device according to an eighth embodiment of the present invention.

FIG. 31 is a front view showing a stop in a projection type color liquid crystal display device according to an eighth embodiment of the present invention.

FIG. 32 is an explanatory diagram showing an optical configuration of a single-panel projection display device according to a ninth embodiment of the present invention.

FIG. 33 is a front view and a side view showing a configuration of a concave mirror used in a display device according to a ninth embodiment of the present invention.

FIG. 34 is an explanatory diagram showing an angular distribution of light passing through a stop in a display device according to a ninth embodiment of the present invention.

FIG. 35 is an explanatory view schematically showing a relationship between a microlens array and a pixel aperture according to a ninth embodiment of the present invention.

FIG. 36 is an explanatory view schematically showing a relationship between one microlens and one pixel opening in the ninth embodiment of the present invention.

FIG. 37 is an explanatory diagram showing an optical configuration of a single-panel projection display device according to a tenth embodiment of the present invention.

FIG. 38 is a front view and a side view of a reflecting mirror according to a tenth embodiment of the present invention.

FIG. 39 is a view for explaining details of the configuration near the reflecting mirror according to the tenth embodiment of the present invention;

FIG. 40 is an explanatory diagram showing an optical configuration of a conventional three-panel projection display device using a microlens array.

FIG. 41 is an explanatory view schematically showing a state in which a microlens on a microlens array in a conventional three-panel projection display device condenses incident light on a pixel opening of a liquid crystal panel and a principle of improving transmittance.

FIG. 42 is an explanatory diagram showing an optical configuration of a single-panel color display device that performs color display using a plurality of dichroic mirrors having different arrangement angles from a conventional microlens using an imaging element array.

FIG. 43 is a graph showing an example of characteristics of three dichroic mirrors constituting a color separation mirror in a conventional single-panel color display device.

FIG. 44 is an explanatory diagram schematically showing an angle of arrangement of three dichroic mirrors constituting a color separation mirror in a conventional single-panel color display device.

FIG. 45 is an explanatory view schematically showing a relationship between a microlens array and a liquid crystal panel in a conventional single-panel color display device.

FIG. 46 schematically shows incident illuminance of a liquid crystal display panel of a conventional projection display device and the projection display device of the present invention,
FIG. 4 is an explanatory diagram showing a relationship between uneven illuminance and peripheral luminance.

FIG. 47 is a schematic configuration diagram of a conventional illuminating device for explaining the principle of realizing uniform illumination using one set of lens arrays.

FIG. 48 is a diagram showing a conventional single-panel projection display device using a color filter using two lens arrays.

FIG. 49 is an explanatory diagram showing an angle distribution of outgoing light in a normal illumination optical system on a plane having an inclination angle θ and an azimuth angle φ of an incident angle with respect to a display panel.

FIG. 50 is an explanatory diagram showing an angle distribution of outgoing light in a lighting device using a 3 × 5 lens array on a plane having an inclination angle θ and an azimuth angle φ of an incident angle with respect to a display panel.

FIG. 51 is an explanatory view schematically showing the maximum distance between the imaging element and the pixel opening when the range of the angle distribution of the incident angle of the incident light is small and large.

FIG. 52 is an explanatory diagram showing, on a plane, an angle distribution after angle separation into three colors in the case of a normal illumination optical system.

FIG. 53 is an explanatory diagram showing, on a plane, an angular distribution after angle separation into three colors in the case of a lighting device using a lens array.

FIG. 54 shows a lens array spacing and a distance between a lens and a condenser lens, a pixel formation interval on a display panel, and an imaging element array and pixels in a lighting device using a lens array and a display panel using an imaging element array. FIG. 3 is an explanatory diagram schematically showing a relationship with a distance between openings.

FIG. 55 is a diagram showing a relationship between a pixel interval and an aperture.

FIG. 56 is a diagram showing a relationship between a pixel interval and an aperture.

FIG. 57 is an explanatory view schematically showing conditions of incident light for preventing occurrence of disturbance of color separation.

[Explanation of symbols]

110, 710, 910, 1001, 1310, 171
0, 2301, 2701, 3201, 3701, 401
0, 4210, 4801 Metal halide lamps 111, 711, 1002, 1711, 2302, 42
11 Elliptical reflector 112, 712, 912, 1003, 1312, 171
2, 2303, 2706, 4012, 4214 Filters for blocking infrared rays and ultraviolet rays 113, 713, 913, 1004, 1313, 171
3, 2304, 2703, 4701, 4804a 1st
Lens arrays 114, 714, 914, 1005, 1314, 171
4, 2704 1802, 3001, 4702, 480
4b Second lens array 115, 715, 915, 1007, 1316, 131
8, 1715, 2305, 2309, 2707, 320
7, 4215, 4805 Condenser lens 116, 716, 916, 1215, 1317, 132
0, 1322, 1716, 2708, 3208, 401
3, 4014, 4017, 4216 Color separation mirror (dichroic mirror) 117, 717, 501, 601, 604, 701, 7
04,917,1332,1717,2710,320
9, 4032, 4218, 4501 Micro lens array 3210 Micro lens 118, 718, 818, 910, 1334, 134
4, 1354, 1718, 2307, 2711, 321
1, 4033, 4043, 4053, 4807 Display panel (liquid crystal panel) 119, 719, 919, 1012, 1336, 171
9, 2309, 2713, 4035 Field lens 120, 720, 920, 1013, 1323, 172
0, 2310, 2714, 4019 Projection lens 121, 721, 921, 1006, 1721, 270
5, 3205, 4213 aperture 122, 722, 922, 1008, 1331, 172
2, 4031 Incident side polarizing plate 123, 723, 923, 1011, 1335, 172
3, 4034, 4220 Emission-side polarizing plate 602, 605, 702, 705, 1102, 210
2, 2202 2703, 2903, 3004 Pixel aperture 703, 706, 1103 Light incident side substrate 911, 4011 Parabolic reflector 909, 1101 Diffraction grating array element 1311 Composite elliptical reflector 1319, 1321, 2815, 2816 Mirror 1401, 1402 Rotation Elliptical surface 2201 Micro lens 230201 to 23015, 32021 to 32024
Reflecting mirror 2412 Conical lens 2702, 3202, 3702 Concave reflecting mirror 3203 Planar mirror 3204 Conical lens 3703, 3912 Polarization beam splitter 3911 Triangular prism 3913 Phase difference plate 3914A, 3914B Convex lens 3915 Reflecting mirror 4020 Screen 4211 Spheroidal reflector 4212 Conical lens

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI G09F 9/00 360 G09F 9/00 360N

Claims (34)

[Claims] 1. A pixel which is a unit for controlling the intensity of transmitted light through an imaging element array formed with a plurality of imaging elements for imaging the irradiation light from a light source. In a display device, which is incident on a display panel arranged in a two-dimensional manner and projects a transmitted light in which the intensity of the irradiation light is controlled to image display means to display an image, the light source and the imaging element array A display device, further comprising a light distribution means for dividing and irradiating the irradiation light to the imaging element array. 2. The display device according to claim 1, wherein said light distribution means comprises a lens array comprising a plurality of lenses, and divides and irradiates said irradiation light for each of said plurality of lenses. A display device, which is a display device. 3. The display device according to claim 2, wherein the lens array includes a first lens array including a plurality of first lenses and a second lens array including a plurality of second lenses. The first lens array splits the illumination light for each of the first lenses and collects the light, and the second lens array includes the first lens. The display device, wherein the second lens is disposed at a position including each of substantially focal positions where the irradiation light is condensed by being divided for each lens by an array. 4. The display device according to claim 3, wherein the first lens array has the plurality of first lenses arranged in one or more rows. Display device. 5. The display device according to claim 3, wherein the second lens array has the plurality of second lenses arranged in one or more rows. Display device. 6. The display device according to claim 3, wherein each imaging element constituting the imaging element array is arranged corresponding to each pixel arranged in the display panel. Characteristic display device. 7. The display device according to claim 3, wherein said imaging element array is constituted by a micro lens. 8. The display device according to claim 3, wherein said imaging element array is constituted by a diffraction grating as an imaging element. 9. The display device according to claim 3, wherein each pixel disposed in the display panel controls transmittance of a pixel opening based on a video signal, and controls each pixel based on a video signal of a different color. A display device, which is arranged corresponding to a set of two or more natural number N pixel apertures for which transmittance control is performed. 10. A display device according to claim 9, wherein a color angle separating means for changing the angle of the emitted light depending on the wavelength of the light is provided between the second lens array and the imaging element array. A display device characterized by being arranged. 11. The display device according to claim 9, wherein the width of the outgoing light in the direction in which the rows of the second lens array are arranged near the second lens array is two times the interval in which the rows are arranged. / N (N is the pixel numerical aperture included in one unit of the pixel). 12. The display device according to claim 1, further comprising a condenser lens having a focal point near the second lens array on an emission side of the second lens array. L is the distance from the lens array, M is the number of rows formed in the second lens array, Pi is the distance between the rows of the second lens array, and Pi is the second lens array of the imaging element array. The formation pitch of the imaging element in the direction in which the columns are arranged is Pp, the distance between the imaging element and the pixel opening of the pixel is t, and the relative distance of the optical medium between the imaging element array and the pixel unit is When the refractive index is n, A display device characterized by satisfying the following conditions: 13. The display device according to claim 3, wherein the imaging elements in the imaging element array are arranged in a direction perpendicular to a direction in which the columns of the second lens array are arranged. A display device, wherein a refractive power is set to be weaker than a refractive power in a direction in which the rows of the second lens array are arranged. 14. The display device according to claim 13, wherein
The display device, wherein the imaging element is formed of a cylindrical lens. 15. The display device according to claim 3, wherein an array of lenses constituting said second lens array is substantially similar to an array of imaging elements of said imaging element array. A display device. 16. The display device according to claim 15, wherein
VF / HF <VP / HP, where VF is the height of the substantially rectangular display unit of the display panel, HF is the width of the display unit, and VP is the vertical arrangement interval of the imaging elements and HP is the horizontal arrangement interval. At this time, the refractive power of the first lens array as a whole is smaller in the vertical direction than in the horizontal direction, and the refractive power of the second lens array as a whole is vertical in the horizontal direction. Is larger and VF / HF> VP / HP, the refractive power of the first lens array as a whole is greater in the vertical direction than in the horizontal direction, and the second lens array is Wherein the refractive power as a whole is set smaller in the vertical direction than in the horizontal direction. 17. The display device according to claim 3, further comprising a reflector having a spheroidal surface and reflecting light from said light source in one direction. 18. The display device according to claim 3, further comprising a reflector having a paraboloid and reflecting light from said light source in one direction. 19. The display device according to claim 1, wherein said light distribution means is an ellipsoidal reflecting mirror composed of two or more different spheroids, and one of two focal points of each spheroid. Wherein the position of the focal point substantially coincides with the position of the light source. 20. The display device according to claim 19, wherein:
A display device, wherein a focal position on the other side of the two focal points of the spheroid is different from each other. 21. The display device according to claim 20, wherein the focal points of said plurality of spheroidal reflecting mirrors are arranged so as to be substantially linear. 22. The display device according to claim 19, wherein:
A display, wherein the elliptical reflecting mirror is constituted by a plurality of spheroidal reflecting mirrors having a solid angle substantially similar to the shape of the display surface of the display panel when viewed from the one-side focal position. apparatus. 23. The display device according to claim 20, wherein a lens is disposed at a position near a focal point on the other side of said plurality of elliptical reflecting mirrors. 24. The display device according to claim 23, wherein the lens is a lens array including a plurality of lenses corresponding to the different focal positions. 25. The display device according to claim 23, wherein the lens array has a concave lens shape as a whole. 26. An illumination system comprising a plurality of first lenses between a light source and an imaging element array on which a plurality of imaging elements for imaging illumination light from the light source are formed. A first lens array that divides light for each of the first lenses and collects the light, and a substantially focal position where the irradiation light is collected by dividing the light for each of the first lenses by the first lens array A second lens array in which a plurality of second lenses are arranged in one or more rows at a position including each of the following; and image display means for displaying an image, wherein the intensity of the irradiation light is provided. A liquid crystal panel for a display device, wherein pixels, which are units for controlling the intensity of transmitted light, are arranged two-dimensionally in order to project the transmitted light controlled by the image display means onto the image display means. 27. A display panel in which a light source, a pixel unit capable of controlling transmittance or reflectance are two-dimensionally arranged, and a control of a transmittance or a reflectance of the display panel to control a light intensity of transmitted light. A light intensity control means for performing the following; a reflecting mirror for condensing light from the light source and directing the light to the display panel; and projecting outgoing light from the display panel onto a screen or a pupil to transmit or reflect light from the screen. Or a display control means for performing display by a light intensity pattern incident from the pupil, wherein the reflecting mirror is arranged such that one of the two focal points of the elliptical surface is located near the light source, and the other focal point is And a plurality of elliptical reflecting mirrors arranged at different positions from each other. 28. The projection display device according to claim 27, wherein a lens is arranged at a position near a focal point on the other side of said plurality of elliptical reflecting mirrors. 29. The projection type display device according to claim 27, wherein the display panel is illuminated with the reflected light of the elliptical reflecting mirror via a common condenser lens having a focal point near the focal point of the elliptical reflecting mirror. A projection display device characterized in that: 30. The projection display device according to claim 27, wherein the elliptical reflecting mirror extends a solid angle substantially similar to the shape of the display surface of the display panel when viewed from the one-side focal position. A projection display device comprising a plurality of spheroidal reflecting mirrors. 31. The projection display according to claim 27, wherein an imaging element corresponding to each pixel unit is provided between said display panel and said light source. apparatus. 32. The projection display device according to claim 31, wherein the pixel unit has an area corresponding to the intensity signals of a plurality of colors, and light is provided between the elliptical reflecting mirror and the imaging element. A projection type display device comprising an angle separating means for changing an incident angle on an image forming element according to the wavelength of the light. 33. The projection display device according to claim 27, wherein the focal points of the plurality of spheroidal reflectors are arranged so as to be substantially linear. 34. The display device according to claim 27, wherein:
A projection display device, wherein a polarization splitting element is arranged near the focal points of the plurality of spheroidal reflecting mirrors.