JPH09243990A - Projection type liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain high-grade videos which have decreased unequal luminosity and colors, is light and has a good contrast by specifying the position of a lens plate which is arranged in the position near a condenser lens among the lens plates consisting of plural unit lenses. SOLUTION: The second lens plate 301 is arranged in the position where nearly the same optical distance as the optical distance of an aperture-stop 105 viewed from the liquid crystal panel on nearly the same plane as the plane of this aperture-stop 105 is attained. The size of the lens aperture of this second lens plate 301 is set smaller than the size of the aperture-stop 105 of the projecting lens. The second lens plate 301 is arranged in the position where nearly the same optical distance as the optical distance of the aperture-stop 105 is attained and, further, the size of the lens aperture is set larger than the effective diaphragm surface of the projecting lens and, therefore, the condensing position of the light made incident on the liquid crystal panel via the second lens plate 301 and reflected is within the effective diaphragm surface 601 of the projecting lens. The efficient incidence of this light on the projecting lens is made possible. The light reflected by the liquid crystal panel is thus efficiently utilized for projection without increasing the size of the projecting lens.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a projection type liquid crystal display device.

[0002]

2. Description of the Related Art A conventional projection type liquid crystal display device will be described with reference to FIG. Irradiation light 310 emitted from the light source 3101
2 passes through the aperture stop 3103 on the incident side and enters the reflection-scattering type liquid crystal panel 3104. The incident light is reflected by the reflection-scattering type liquid crystal panel 3104 and is enlarged and projected on a screen (not shown) via the aperture stop 3105 and the projection lens 3106.

Each pixel of the reflection / scattering type liquid crystal panel 3104 can specularly reflect or scatter incident light by applying a predetermined voltage. The specular reflected light 3107 represented by the solid line represents the reflected light in the state where the light is not scattered, and the scattered reflected light 3108 represented by the broken line represents the light scattered by the liquid crystal panel 3104. At this time, almost all the specular reflected light 3107 passes through the opening of the aperture stop 3105 and reaches the screen through the projection lens 3106, but the scattered reflected light 3108 is blocked by the aperture stop 3105.
Hardly reaches the screen. Therefore, the light reflected by the pixels in the specular reflection state of the liquid crystal panel 3104 passes through the aperture stop 3105 and is displayed brightly on the screen through the projection lens 3105, but the light reflected by the pixels in the scattering state is the aperture stop. It is blocked by 3105 and becomes dark on the screen. As described above, in the projection type liquid crystal display device using the reflection-scattering type liquid crystal panel, the light from the light source unit is modulated into the image light by controlling the degree of scattering of the reflection of the light.

In the projection type liquid crystal display device having this structure, the TN
Unlike a projection type liquid crystal display device using a (Twisted Nematic) type liquid crystal panel, there is no light loss due to a polarizing plate, so a bright image can be obtained on the screen. Further, in the reflection type liquid crystal panel, the electrodes can also serve as the reflection plate, and the aperture ratio of the pixels can be increased as compared with the transmission type liquid crystal panel, so that a brighter image can be obtained on the screen.
Further, since the optical path of the optical system of the reflection type liquid crystal panel is folded back, the optical system can be made smaller than that of the projection type liquid crystal display device using the transmission type liquid crystal panel.

In such a projection type liquid crystal display device, it is important to use the light from the light source section with high efficiency and to reduce the uneven illuminance and the uneven color on the screen.

An optical integrator composed of two lens plates having a plurality of lenses arranged in the same plane is known as a means for improving the utilization efficiency of the light from the light source and improving the unevenness in illuminance and color on the screen. And is disclosed in JP-A-3
The construction of a projection type liquid crystal display device using this optical integrator optical system is described in Japanese Patent Publication No.-111806. In this, the light from the light source unit is divided into a plurality of light fluxes by the first lens plate, and these light fluxes are superimposed and imaged on the display area of the liquid crystal panel via the second lens plate.

According to this method, since the luminous flux with small illumination unevenness after division is superimposed on the display area of the liquid crystal panel, highly uniform illumination light can be obtained. Therefore, the unevenness of illuminance and the unevenness of color on the screen are significantly reduced. Further, if the opening of each unit lens forming the first lens plate has a shape similar to the display area of the liquid crystal panel, the luminous flux after division can be radiated to the display area without excess or deficiency, so that the illumination can be performed efficiently. can do.

[0008]

When such an optical integrator is used, the second lens plate apparently becomes a large light source having a plurality of light emitting portions, and the parallelism of light incident on the liquid crystal panel is deteriorated. In this case, in order to efficiently use the light reflected by the liquid crystal panel for projection, it is necessary to make the aperture stop aperture large and further enlarge the projection lens. When the aperture area of the aperture stop is increased, the screen illuminance can be increased, but the contrast ratio is lowered and the practically necessary contrast ratio cannot be realized. In addition, an increase in the size of the projection lens causes problems such as an increase in the size of the entire apparatus and a high cost.

An object of the present invention is to provide a projection type liquid crystal display device capable of displaying a high-quality image which is bright and has a high contrast ratio, with less unevenness in brightness and color.

[0010]

A projection type liquid crystal display device according to the present invention includes a light source section, a condenser lens for collecting light from the light source section, and a reflection for irradiating the light collected by the condenser lens. A scattering type liquid crystal panel, a projection lens for projecting light modulated by the reflection scattering type liquid crystal panel through the condenser lens, an aperture stop positioned between the condenser lens and the projection lens, and the projection lens. A projection type liquid crystal display device having a screen on which the reflected light is projected, wherein two lens plates each including a plurality of unit lenses are provided between the light source unit and the condenser lens. Among the plates, the lens plate located near the condenser lens is placed at a position that has almost the same optical distance as the aperture stop when viewed from the reflection-scattering liquid crystal panel, and the size of the lens aperture of this lens plate is set to From the size of the diaphragm It is obtained by fence.

Further, between the light source section and the condenser lens, one lens plate having a plurality of lenses arranged in a plane perpendicular to the main axis of the output light from the light source section is arranged. All of the individual unit lenses that make up the lens plate have converging positions (optical axes) at different positions, and the maximum amount of deviation of the converging positions (optical axes) between these unit lenses is determined by the projection lens system. It may be smaller than the size of the aperture stop. Furthermore, it is desirable that the aspect ratio of the amount of deviation of the condensing position (optical axis) of each lens forming the lens plate be the same as the width / height ratio of the display section of the reflection-scattering type liquid crystal panel.

Further, the shape of the opening of the unit lens constituting the lens plate arranged closest to the light source part of the lens plate is similar to the display part of the reflection-scattering type liquid crystal panel, and each lens opening is It is desirable that the section is inscribed in the cross-sectional shape of the output light from the light source section or arranged so as to be included in the cross-sectional shape of the output light.

[0013]

1 is a schematic sectional view showing the structure of a projection type liquid crystal display device of the present invention. As shown in FIG. 1, this projection type liquid crystal display device includes a light source 101 and a reflecting mirror 102.
A light source unit consisting of, a filter 103, a first lens plate 201, a second lens plate 301, and a red reflective film 110.
The dichroic prism 110 provided with the R and blue reflection films 110B, and the dichroic prism 110
A blue reflection / scattering liquid crystal panel 107, a green reflection / scattering liquid crystal panel 108, a red reflection / scattering liquid crystal panel 109, and a projection lens 111, which are respectively arranged on one side surface.
, Dichroic prism 110 and projection lens 111
And a condenser lens 104 disposed between and
The aperture stop 105 is provided in the vicinity of the focal point of No. 04, and the minute reflecting mirror 106 is provided so as to face the aperture stop 105 at a predetermined angle.

A light source having a short arc length such as a halogen lamp, a metal halide lamp or a xenon lamp is used as the light source 101 constituting the light source section. A rotary paraboloid is used as the reflecting mirror 102, and the paraboloid is arranged at the focal position so that the long axis of the light emitting body of the light source 101 is parallel to the main axis of the light emitted from the light source unit. The light emitted from the light source 101 is reflected by the reflecting mirror 10.
It is reflected by 2 and emits light in a substantially parallel state. As the reflecting mirror 102, it is possible to use, besides the paraboloidal mirror, a mirror whose inclination in each cross section is continuously determined by calculation. Further, a rotating ellipsoidal mirror may be used as the reflecting mirror 102, and it may be configured to emit approximately parallel light in combination with a collimator lens.

The output light in a substantially parallel state emitted from the light source section is filtered by the filter 103 to block infrared light and ultraviolet light, and then passes through the first lens plate 201 and then passes through the minute reflecting mirror 106.
The direction is changed by and the light enters the second lens plate 301.

The first lens plate 201 and the second lens plate 301 are obtained by arranging a plurality of unit lenses in the same plane, and the first lens plate 201 is located between the light source section and the micro-reflecting mirror 106. The second lens plate 301 is disposed in the vicinity of the light source section of the aperture stop 105, and is disposed at a position having substantially the same optical distance as the aperture stop 105 when viewed from the liquid crystal panel on the same plane as the aperture stop 105.

The substantially parallel output light from the light source section is the first
When passing through the lens plate 201 of the first lens plate 201
The unit lenses that make up the
Since it has the (optical axis), it is divided into the same number of light beams as the number of unit lenses forming the first lens plate 201. The split light flux is changed in direction by the micro-reflecting mirror 106, and then enters the unit lens forming the second lens plate 301.

An example of the appearance of the first lens plate 201 is shown in FIG.
Is shown in FIG. 2 is a schematic view of the first lens plate 201 composed of four unit lenses. The shape of the opening of each unit lens forming the first lens plate 201 is a rectangular shape similar to the shape of the display section of the liquid crystal panel, and the openings of these unit lenses are for the output light from the light source section. It is arranged so as to be inscribed in or inside the cross-sectional shape. Further, a portion outside the lens opening portion 202 of the first lens plate and irradiated with the output light from the light source portion may be blocked and absorbed by the light shielding means 203.
As the light-shielding means 203, a heat-resistant material that can withstand a temperature rise due to the output light from the light source is made black so as to absorb visible light, for example, a heat-resistant material such as aluminum that is blackened by alumite treatment or the like. It may be realized by sticking the heat-resistant plastic to the lens or by disposing the heat-resistant plastic near the lens, or by coloring the corresponding part of the lens plate itself. In this case, of the output light from the light source unit, unnecessary light reaching the outside of the lens opening of the first lens plate is absorbed by the light shielding unit, so that the projection optical system including the condenser lens 104, the projection lens 111, etc. It never enters the system. Therefore, there is an effect that it is possible to prevent deterioration of image quality such as a decrease in contrast ratio due to stray light or the like caused by unnecessary light.

Further, the light shielding means 203 may be constituted by a reflecting surface which is perpendicular to the main axis of the light emitted from the light source section in a substantially parallel state. The reflecting surface may be realized by coating a metal film of Al or the like on the corresponding portion, or may be realized by coating a dielectric multilayer film.

In this case, of the output light from the light source section, the light reaching the outside of the lens opening returns to the light source section. Therefore, similarly to the case where the absorbing surface is provided as the light shielding unit 203, it is possible to prevent the deterioration of the image quality such as the reduction of the contrast ratio due to the unnecessary light. Further, the light reflected by the reflecting surface and returned to the light source section is reflected by the reflecting mirror 102 a plurality of times and then comes out toward the lens opening section of the first lens plate again, so that the light originally discarded as unnecessary light. The effect is that the light can be reused, and the light utilization efficiency can be improved.

FIG. 3 shows the first lens plate 201 shown in FIG.
It is a front view showing an example of the appearance of the 2nd lens board 301 corresponding to. The second lens plate has a function of enlarging (or reducing) an image in the vicinity of each unit lens forming the first lens plate and transmitting and superimposing the image through the condenser lens 104 to the display area of the liquid crystal panel which is the irradiation target. have. Therefore, the number of unit lenses forming the second lens plate is equal to the number of unit lenses of the first lens plate, and each unit lens has a one-to-one correspondence with the corresponding unit lens of the first lens plate. .

Here, general positions of a unit lens (hereinafter referred to as a lens A for convenience) constituting the first lens plate and a corresponding unit lens of a second lens plate (hereinafter referred to as a lens B for convenience) corresponding thereto. Describe the relationship.

As described above, the second lens plate is arranged at a position having an optical distance substantially the same as that of the aperture stop 105 as seen from the liquid crystal panel, so the lens B is installed at a position corresponding to this. The lens B has a role of enlarging (or reducing) the image in the vicinity of the lens A and transmitting it to the display area of the liquid crystal panel. It is necessary to make the magnification of B correspond to the ratio of the size of the aperture shape of the lens A to the size of the display area of the liquid crystal panel.

Here, consider a case where the irradiation targets of the lens A and the lens B are sequentially arranged vertically on the same axis. The distance between the two lenses is L1, the distance between the lens B and the irradiation target is L
When 2, the relationship of the size of the image in the vicinity of the lens A: the size of the illumination target = L1: L2 is generally established. Based on this relationship, the distance between the lenses B and A and the focal length of the lens B can be determined. In the case of this embodiment, the condenser lens 104 and the dichroic prism 110 are further added.
The distance between the lenses and the focal length may be determined in consideration of the above.

On the other hand, the lens A has a role of enhancing the light transmission efficiency of the lens B. Therefore, the focal length of the lens A is set to be equal to the distance L1 between the lens A and the lens B, and the focusing position (optical axis) of the lens A is such that the main axis of the light passing through the lens A is the center of the lens B. It is set up to reach the department.

For this reason, the light flux that is incident on the first lens plate and is split forms a light emitter image (302 in FIG. 3) of the light source 101 on the opening of the corresponding unit lens of the second lens plate. It will be. At this time, if the light-emitting body image formed by each unit lens forming the first lens plate protrudes from the opening of the corresponding unit lens of the second lens plate, the protruding light is not properly irradiated to the liquid crystal panel, resulting in loss. Become light. Therefore, in order to irradiate the liquid crystal panel with light from the light source section with high efficiency, the aperture of the unit lens forming the second lens plate is formed by the corresponding unit lens of the first lens plate. Needs to be shaped so that it fits inside. Therefore, if this condition is satisfied, the fan shape is not limited to that shown in FIG.

Here, in the case where the light source 101 has two light emitting portions, the number of light emitting body images formed on the second lens plate is twice the number of unit lenses forming the first lens plate. Become. In this case, the number of unit lenses forming the second lens plate may be twice the number of unit lenses forming the first lens plate.

It should be noted that at the light-condensing position (optical axis) of the unit lenses forming the second lens plate, an image near the corresponding unit lens of the first lens plate is displayed on the liquid crystal panel via the light-condensing lens 104. It is set so as to form a superimposed image on the area.

FIG. 4 is a front view showing the appearance of another example of the second lens plate 301. This lens plate is the second one described above.
The lens plate 301 is provided with the light shielding means 401 to limit the shape of the lens opening portion 402. The lens opening 402 is formed by the first lens plate 201 and the second lens plate 3.
The light-emitting member image 302 formed on 01 is set within the inside of the light-emitting member image 302 without excess or deficiency, or is limited by the light shielding unit 401 so as to be slightly larger than the light-emitting member image 302 as shown in FIG. The light-shielding means 401 is made of a heat-resistant material that can withstand a temperature rise due to the output light from the light source, colored black so as to absorb visible light, for example, a heat-resistant material such as aluminum that has been blackened by alumite treatment or a black heat-resistant plastic. Can be realized by sticking to the lens, or by coloring the corresponding part of the lens plate itself in black. Here, the second lens plate 301 is installed at a position having the same optical distance as that of the aperture stop 105 when viewed from the liquid crystal panel, and the light shielding means 401 is disposed on substantially the same plane as the aperture stop 105. This position is a position suitable for narrowing the incident light to the liquid crystal panel. In this case, it is possible to prevent unnecessary light, which is included in the output light from the light source unit, from passing through the first lens plate 201 and reaching the second lens plate 301 and including a scattered component, from entering the projection optical system. There is an effect that it is possible to prevent deterioration of image quality such as a decrease in contrast ratio due to stray light caused by light.

The micro-reflecting mirror 106 is composed of a reflecting surface and a non-reflecting surface, and the reflecting surface has a role of changing the traveling direction of light passing through the first lens plate 201 and guiding it to the second lens plate 301. The non-reflective surface has a role of blocking unnecessary light.

The light beam whose direction is changed by the minute reflecting mirror 106 goes to the condenser lens 104 via the second lens plate 301. The light incident on the condenser lens 104 receives the light from the condenser lens 10
After being converted into substantially parallel light by 4, the light enters the dichroic prism 110.

In the dichroic prism 110, a red reflection film 110R and a blue reflection film 110B are provided inside at right angles to each other, and a reflection / scattering liquid crystal panel 107 for blue color is provided.
Is the side surface of the dichroic prism 110 facing the reflecting surface of the blue reflecting film 110B, and the red reflective scattering liquid crystal panel 109 is the side surface of the dichroic prism 110 facing the reflecting surface of the red reflecting film 110R. Type liquid crystal panel 108 is a dichroic prism 110.
Are arranged on the side surfaces facing the entrance and exit surfaces, respectively.

The dichroic prism used in the present invention separates the white light incident on the dichroic prism into three colors, irradiates the liquid crystal panel corresponding to each color, and combines the light reflected by each liquid crystal panel again to form an incident surface. The dichroic prism configured to emit light from the same surface is not limited to the so-called cross dichroic prism as shown in FIG.

FIG. 5 is a schematic sectional view showing another example of the dichroic prism used in the projection type liquid crystal display device of the present invention. This dichroic prism 501 is composed of three prisms, and is configured to separate incident white light into three primary colors by a blue reflection film 501B and a red reflection film 501R. The liquid crystal panels 109, 108 and 107 are arranged at the positions shown in the figure. Reflective / scattering type liquid crystal panel 107, 1
08 and 109 are thin film transistors having a reflective electrode, nonlinear two-terminal element (MIM, etc.) glass substrate, MOS
A single crystal silicon substrate on which a transistor is formed and a transparent glass substrate facing the single crystal silicon substrate, on which a polymer dispersed liquid crystal layer is formed can be used.

Between the dichroic prism and the reflection / scattering type liquid crystal panels 107, 108 and 109, oil or silicon gel having the same refractive index as glass as the material of the display part of the dichroic prism and the reflection / scattering type liquid crystal panel is injected. It is desirable to remove or reduce the surface reflection of the dichroic prism and the reflection-scattering type liquid crystal panel. Light incident on the dichroic prism 110 is red
(R), green (G), and blue (B) are separated into three primary colors, and three liquid crystal panels 109, 108, 1 corresponding to the respective colors are provided.
07. At this time, for the incident light on the display area of the liquid crystal panel, the output light from the light source unit is split by the first lens plate,
Since the light flux with small unevenness in illumination after division is superposed on the display area of the liquid crystal panel via the second lens plate without excess or deficiency, uniform illumination light without unevenness in color or unevenness in brightness is obtained.

The light incident on the liquid crystal panel is modulated according to the image information of each color. That is, the incident light is specularly reflected when each pixel of the liquid crystal panel is in the reflection mode, and is scattered in the scattering mode.

The light reflected by the liquid crystal panel is recombined by the dichroic prism 110 and condensed by the condenser lens 104. At this time, since the main axis of the light incident on the liquid crystal panel is not vertical and is inclined by a few degrees (preferably between 0.1 and 10 degrees), the light reflected by the liquid crystal panel is different from the position of the micro-reflecting mirror 106. The light is condensed in the vicinity of the aperture stop 105 at a slightly displaced position.

The light passing through the aperture stop 105 is enlarged and projected on the screen 112 via the projection lens 111.
At this time, of the light that has entered the liquid crystal panel, the light of the pixel that is specularly reflected passes through the aperture of the aperture stop 105, and the projection lens 1
It is magnified by 11 to reach the screen and becomes brighter. On the other hand, the light of the pixel which is scattered and reflected is blocked by the light-shielding portion of the aperture stop 105 and the minute reflecting mirror 106, and hardly reaches the screen, and the pixel becomes dark.

FIG. 6 is a view showing the opening of the projection lens of the projection type liquid crystal display device of the present invention, which includes an aperture stop 105,
An example of the second lens plate 301 having the light blocking means 401 and the aperture stop surface 601 of the projection lens is illustrated.

In the projection type liquid crystal display device of the present invention, the folding optical system is off-axis, and the aperture stop 6 of the projection lens is
The lower part of 01 is the second lens plate 3 having the light shielding means 401.
Since it is covered with 01, only the upper part of the aperture stop 601 of the projection lens can be used to project the light reflected by the liquid crystal panel.

Here, the projection type liquid crystal display device of the present invention is characterized in that the size of the lens aperture of the second lens plate 301 is smaller than the size of the aperture stop of the projection lens.

Therefore, the size of the lens aperture of the second lens plate 301 is less than half the size of the aperture stop 601 of the projection lens 111, that is, the size of the aperture stop 601 that fits inside a semicircle divided into two. It has become.

As described above, the light incident on the liquid crystal panel is obtained by splitting the light from the light source portion by the first lens plate 201 and superposing it on the display area of the liquid crystal panel via the second lens plate 301. The second lens plate 301 apparently serves as a light source having a plurality of light emitting parts, and the parallelism of light incident on the liquid crystal panel is deteriorated. That is, a plurality of light beams enter the liquid crystal panel from different positions at different angles. Therefore, the light reflected by the liquid crystal panel is condensed at a plurality of different positions in the plane near the aperture stop 105 in a plane perpendicular to the main axis of the reflected light of the liquid crystal panel.

At this time, the second lens plate 301 of the present invention is used.
Is disposed at a position having an optical distance substantially the same as that of the aperture stop 105 when viewed from the liquid crystal panel, and the size of the lens opening is smaller than the effective stop surface of the projection lens. Therefore, the condensing position of the light that is incident on the liquid crystal panel via the second lens plate 301 and reflected is at the effective diaphragm surface 6 of the projection lens.
01, so that the light can efficiently enter the projection lens. That is, there is an effect that the light reflected by the liquid crystal panel can be efficiently projected and used without increasing the size of the projection lens.

Here, in order to more reliably make the light specularly reflected by the liquid crystal panel enter the diaphragm surface of the projection lens, the size of the second lens plate, which is apparently a light source having a plurality of light emitting points, is smaller. However, in this embodiment, it is smaller than the circle inscribed in the semicircle which is the effective diaphragm surface of the projection lens.

Next, the shape of the aperture of the aperture stop 105 will be described.

FIG. 7 is a diagram showing an example of a cross-sectional shape 701 of light specularly reflected by the liquid crystal panel and condensed by the condenser lens 104 in the vicinity of the aperture stop 105. As illustrated, when the light reflected by the liquid crystal panel is condensed by the condenser lens 104 in the vicinity of the aperture stop 105, the same number of light fluxes as the unit lenses forming the first lens plate are radially arranged. This corresponds to the light emitter image obtained when the output light from the light source unit is split by the first lens plate and condensed on the second lens plate. In the case of the present embodiment, when the light source 101 is viewed from each unit lens of the first lens plate through the reflecting mirror 102, the light-emitting body of the light source 101 has an elongated shape similar to an ellipse, and thus is obtained. The illuminant image also has elongated illuminators arranged radially.

In the conventional projection type liquid crystal display device, no consideration is given to the shape of the aperture of the aperture stop, and a single circle of the aperture stop of the projection lens or a rectangle of the liquid crystal panel is used. An opening was used.
In this case, the state of the light reflected by the liquid crystal panel and condensed by the condenser lens 104 does not match the shape of the aperture of the aperture stop. Therefore, if you simply increase the area of the aperture to obtain sufficient illuminance on the screen, a large amount of light scattered and reflected by the liquid crystal panel will pass through the aperture stop.
The portion to be displayed in black also becomes bright, and there arises a problem that a practically necessary contrast ratio cannot be obtained.

On the other hand, the aperture stop 105 of the projection type liquid crystal display device of the present invention is characterized by having an opening having a shape corresponding to the state of light reflected by the liquid crystal panel and condensed by the condenser lens 104.

Specifically, as shown in FIG. 8, an aperture stop having apertures 801 in which the same number of minute apertures as the first lens plate are arranged radially. Alternatively, FIG.
As shown in FIG.
Thus, an aperture stop having a single radial opening 901 can be used by making the cross-sectional shape 701 of the condensed light a little larger and fusing them.

The light-shielding and absorbing portions 802, 90 of the aperture stop
As the material of 2, a heat-resistant material capable of withstanding a temperature rise due to light reflected by the liquid crystal panel may be blackened so as to absorb visible light. For example, aluminum blackened by alumite treatment may be used. However, black heat-resistant plastic may be used.

In this case, the shape of the aperture of the aperture stop 105 is adapted to the cross-sectional shape of the light beam reflected by the liquid crystal panel and condensed by the condenser lens 104. Therefore, the light specularly reflected by the liquid crystal panel appropriately passes through the opening and enters the projection lens, but the light scattered and reflected by the liquid crystal panel is sufficiently absorbed by the light shielding and absorbing section of the aperture stop and does not reach the projection lens. Absent. Therefore, there is an effect that a brighter high-quality image with a higher contrast ratio can be obtained on the screen.

FIG. 10 is a schematic front view showing the appearance of another example of the first lens plate 201 used in the projection type liquid crystal display device of the present invention. This lens plate has the same concept as that of the first lens plate shown in FIG. 2 except that the number of unit lenses constituting the lens plate is 10. The aperture shape of each unit lens has a rectangular shape similar to that of the display unit of the liquid crystal panel, and the unit lenses are arranged inscribed in the cross-sectional shape of the output light from the light source unit or densely arranged within the inside. The lens opening 1001 may be formed by adhering a plurality of lenses to be integrated, or may be integrally formed from the beginning. Further, a portion other than the lens opening portion of the first lens plate, which is irradiated with the output light from the light source portion, may be shielded by the light shielding unit 1002. Like the light blocking means 203 of the first lens plate shown in FIG. 2, the light blocking means 1002 may be configured with a surface that absorbs visible light or a surface that reflects visible light.

Since the first lens plate shown in FIG. 10 is composed of ten unit lenses, when the output light in the substantially parallel state from the light source section passes through the first lens plate, ten light beams are emitted. Is divided into Therefore, the second lens plate is also composed of 10 unit lenses. Although not shown, the second lens plate is composed of the same number of unit lenses as the first lens plate, and each unit lens emits light formed by the corresponding unit lens of the first lens plate. It has an opening that allows the body image to fit inside.

Here, in the first lens plate shown in FIG. 10, the distance between the optical axis of the output light from the light source unit and each unit lens is not always equal. In this case, the illuminant image formed by the unit lens located near the optical axis of the output light from the light source unit tends to be large, and the illuminant image formed by the unit lens located far from the optical axis of the output light tends to be small. Therefore, it is desirable that the shape of the opening of each unit lens of the second lens plate be different correspondingly.

FIG. 11 is a diagram showing an example of the cross-sectional shape of the light beam specularly reflected by the liquid crystal panel and condensed near the aperture stop 105 when the first lens plate shown in FIG. 10 is used. As shown in the figure, the light reflected by the liquid crystal panel and condensed by the condenser lens 104 is in a state in which the same number of light beams as the number of unit lenses forming the first lens plate are radially arranged. This corresponds to the light-emitting body image obtained when the output light from the light source unit is split by the first lens plate and condensed on the second lens plate.

In the first lens plate shown in FIG. 2, since each unit lens is located at the same distance from the optical axis of the output light from the light source section, which light-emitting element image is formed on the second lens plate is emitted. The figure also had the same shape. Therefore, the aperture stop 105
The sectional shapes of the divided luminous fluxes in the vicinity were also substantially the same. However, in the first lens plate shown in FIG. 10, the optical axis of the output light from the light source unit and the position of each unit lens are not always equal, so that the size of the light emitter image formed by the first lens plate is large. Cannot be the same. Therefore, as illustrated in FIG. 11, the cross-sectional shapes of the respective divided light beams in the vicinity of the aperture stop 105 do not match, and the light beam closer to the main axis of the specularly reflected light from the liquid crystal panel has a larger cross-sectional shape, and the farther away it is, the smaller the light beam becomes. ing.

FIGS. 12, 13 and 14 are views showing an example of an aperture stop corresponding to the first lens plate shown in FIG.

FIG. 12 shows an aperture stop having an opening 1201 which is specularly reflected by the liquid crystal panel and is condensed by the condenser lens 104 in the vicinity of the aperture stop, and which has an opening 1201. The same number of minute apertures as the unit lenses are arranged in a radial pattern. The size of the minute aperture is larger as it is closer to the main axis of the light reflected by the liquid crystal panel, that is, closer to the center position of the aperture diaphragm, and is smaller as it is farther away.

FIG. 13 shows an opening 1301 which is slightly larger than the cross-sectional shape 1101 of the light beam which is specularly reflected by the liquid crystal panel and is condensed by the condenser lens 104 in the vicinity of the aperture stop 105. The openings near the main axis are fused so that the number of minute openings is smaller than the number of unit lenses forming the first lens plate. That is, the individual small apertures of the aperture stop shown in FIG. 12 are widened and a part of them is fused.

FIG. 14 shows a single radial opening portion in which the cross-sectional shape 1101 of the light beam specularly reflected by the liquid crystal panel and condensed by the condenser lens 104 in the vicinity of the aperture stop 105 is enlarged and fused into one. It is an aperture stop having 1401. That is, each aperture of the aperture stop shown in FIG. 12 is widened to have a single radial aperture in which all the apertures are fused.

Therefore, in the aperture stop shown in FIGS. 12, 13 and 14, the area of the aperture is increased in this order.

It should be noted that the light-shielding and absorbing portions 1202, 1 of the aperture stop
For 302 and 1402, a heat-resistant material that can withstand a rise in temperature due to light reflected by the liquid crystal panel may be a color that absorbs visible light, that is, black, and for example, aluminum that is blackened by alumite treatment may be used. Alternatively, black heat-resistant plastic may be used.

FIGS. 15 and 16 are diagrams showing the relationship between the aperture area and the contrast ratio of the aperture stop, and the relationship between the aperture area and the screen illuminance, respectively.

In the conventional aperture stop, no consideration is given to the shape of the opening, and the shape of the opening does not match the cross-sectional shape of the light beam specularly reflected by the liquid crystal panel and condensed by the condenser lens. On the other hand, in the aperture stop according to the present invention illustrated in FIGS. 12, 13, and 14, the shape of the opening is matched with the cross-sectional shape of the light beam that is specularly reflected by the liquid crystal panel and condensed by the condenser lens.

Therefore, even if the aperture area of the aperture stop is the same, a part of the light specularly reflected by the liquid crystal panel is eclipsed by the conventional aperture stop, and sufficient brightness cannot be obtained. Since a large amount of the generated light passes through the aperture stop and brightens the black display portion, a sufficient contrast ratio cannot be obtained.

On the other hand, in the aperture stop according to the present invention, the light specularly reflected by the liquid crystal panel passes through the aperture stop without being rejected, and the light scattered and reflected by the liquid crystal panel is appropriately shielded and absorbed by the aperture stop and projected onto the projection lens. Since it is not incident on Fig. 1
As shown in FIGS. 5 and 16, compared to the conventional aperture stop, there is an effect that a brighter image on the screen and a high-quality image with a higher contrast ratio can be obtained.

Further, the following effects can be obtained by making it possible to switch the shape of the aperture of the aperture stop like the aperture stop shown in FIGS. 12, 13 and 14.

That is, between the aperture area of the aperture stop and the screen illuminance and the contrast ratio, there are respectively FIGS.
Since there is a relation shown in 6, a bright and easy-to-see image is realized by using an aperture stop with a large opening area when viewing in a bright room, and an aperture stop with a small opening area is used when viewing in a dark room. Therefore, there is an effect that a desired image can be realized by switching the shape of the aperture of the aperture stop 105 such that an image with a high contrast ratio is realized.

Incidentally, if the number of unit lenses constituting the first lens plate is increased, the output light from the light source section can be divided more finely, and thus the uneven illumination of individual light fluxes after the division is reduced, and the liquid crystal panel Can be illuminated more uniformly.

However, since the size of the lens aperture of the second lens plate is specified to be smaller than the size of the effective aperture stop of the projection lens, the second lens plate is formed when the number of unit lenses increases. The size of the opening per unit lens becomes smaller. In this case, since it is conceivable that the light flux divided by the first lens plate does not completely enter the opening of the corresponding unit lens of the second lens plate and the light utilization efficiency decreases, so that the number of unit lenses is large. The more you have, the better.

Therefore, the number of unit lenses constituting the lens plate may be determined so as to obtain a desired performance in accordance with each system, and 4 or 10 used in the above embodiment.
It is not limited to individuals.

FIG. 17 is a schematic sectional view showing the outline of another embodiment of the projection type liquid crystal display device of the present invention. The projection-type liquid crystal display device shown in FIG. 1 has basically the same configuration except that the positions of the micro-reflecting mirror 106 and the second lens plate 301 are different. To do.

In the projection type liquid crystal display device of the present invention, the aperture stop 105 is arranged near the condensing point of the condensing lens 104, and the second
The aperture plate 105 when the lens plate 301 is viewed from the liquid crystal panel.
It is characterized in that it is arranged at a position that has almost the same optical distance as. Therefore, as shown in FIG. 17, the second lens plate 3
01 may be arranged between the first lens plate 201 and the minute reflecting mirror 106. In this case, the first lens plate 201 and the second lens plate 301 are arranged on the same axis.

FIG. 18 is a front view showing an aperture stop of the projection lens 111 of this projection type liquid crystal display device, and shows a case where a lens plate composed of four unit lenses is used. In the figure, an aperture stop 105 and a minute reflection surface 1801
An example of the micro-reflecting mirror 106 including the light-shielding and absorbing portion 1802 and the aperture stop 601 of the projection lens is illustrated.

As shown in the figure, the shape of the micro-reflecting surface 1801 of the micro-reflecting mirror 106 is a radial pattern corresponding to the state of the light beam emitted from the second lens plate 301 on the projection image on the plane perpendicular to the optical axis of the projection lens. It is designed to have a shape. In this case, the micro-reflecting mirror 106 has a function as a diaphragm on the incident side, and it is possible to prevent diffused unnecessary light from entering the projection optical system, so that the contrast ratio is reduced due to stray light caused by unnecessary light. Can be prevented.

In this case as well, similar to the projection type liquid crystal display device shown in FIG. 1, the effect of the two lens plates enables uniform illumination with little brightness and color unevenness on the liquid crystal panel, so that the illuminance on the screen is reduced. It is possible to display an image with excellent image quality without uneven color. Further, since the shape of the opening of the aperture stop 105 is adapted to the cross-sectional shape of the light reflected by the liquid crystal panel, the light specularly reflected by the liquid crystal panel appropriately passes through the aperture stop and is scattered by the liquid crystal panel. The reflected light is sufficiently absorbed by the aperture stop and does not enter the projection lens. Therefore, a high-quality image that is brighter and has a higher contrast ratio can be obtained on the screen.

FIG. 19 is a schematic sectional view showing the outline of another embodiment of the projection type liquid crystal display device of the present invention. The light source portion including the light source 101 and the reflecting mirror 102 is provided as a dichroic prism 1.
The condenser lens 104 is disposed between the condenser lens 104 and the condenser lens 104. An exit-side aperture stop 105 in the Schlieren optical system is arranged in the vicinity of the converging point of the condenser lens 104, and a light-shielding means 1701 as an entrance-side aperture stop and a second lens are arranged on substantially the same plane as the aperture stop 105. Board 301
Are placed in contact with each other. Further, the first lens plate 201 is arranged between the second lens plate 301 and the light source unit. The reflecting mirror 1903 is arranged in the vicinity of the aperture stop 105 and on the side opposite to the dichroic prism 110 with a predetermined angle so that the reflected light from the liquid crystal panel can be bent at an angle close to a right angle and guided to the projection lens 1904.

In this case as well, similar to the projection type liquid crystal display device shown in FIGS. 1 and 18, the effect of the two lens plates enables uniform illumination with little brightness and color unevenness on the liquid crystal panel, so that the screen It is possible to display an image with excellent image quality without unevenness in illuminance and color. further,
Since the shape of the aperture of the aperture diaphragm matches the cross-sectional shape of the light reflected by the liquid crystal panel, it is brighter on the screen,
High-quality images with a higher contrast ratio can be obtained.

Further, since the small reflecting mirror 1904 is arranged where the projected image is small, a small rear projection type projection type liquid crystal display device having a small depth can be realized.

In the projection type liquid crystal display device described so far, the two lens plates constitute the illumination optical system for uniformly illuminating the liquid crystal panel. However, between the light source section and the condenser lens 104. It goes without saying that another lens may be arranged in addition to the first and second lens plates to enhance the light collection efficiency and illumination efficiency of the source light.

Further, it is possible to construct an illumination optical system for uniformly illuminating the liquid crystal panel with one lens plate.

FIG. 20 is a schematic sectional view showing an example of a projection type liquid crystal display device of the present invention in which an illumination optical system for uniformly illuminating a liquid crystal panel is constituted by one lens plate. The illumination optical system has a single lens plate 200 instead of two lens plates.
1 and FIG. 1 except that a light source unit including a light source 101 and a reflecting mirror 102 is arranged between the minute reflecting mirror 106.
This is the same as the projection type liquid crystal display device shown in FIG.

The lens plate 2001 has a plurality of unit lenses arranged in a plane perpendicular to the main axis of the output light from the light source section, and divides the light emitted from the light source section into a plurality of light fluxes and divides the light fluxes into a liquid crystal. The focal length and condensing position (optical axis) of each unit lens are defined so that they can be superimposed on the display portion of the panel.

Next, the lens plate 2001 will be described in detail with reference to the drawings.

FIG. 21 is a front view showing an embodiment of the lens plate 2001. The lens plate 2001 is composed of four lens-shaped condensing lenses 2002, 2003, 200 having the same focal length in a plane perpendicular to the main axis of the output light from the light source unit.
4, 2005 are arranged as shown. Each lens has a condensing position (optical axis) 2002c at a different position,
2003c, 2004c, 2005c, the maximum amount h of the deviation of the condensing position (optical axis) of each unit lens is set smaller than the size of the effective aperture stop of the projection lens.

Further, it is desirable to set the deviation amount of the condensing position (optical axis) of each unit lens to the same ratio as the width / height ratio of the display portion of the liquid crystal panel which is the irradiation target. That is, if the width / height ratio of the display portion of the liquid crystal panel is 4: 3, x2 +
x3 (= x5 + x4): y2 + y5 (= y3 + y4) =
The condensing position (optical axis) of each unit lens is set at a position of 4: 3. When the central principal axis of the output light from the light source unit and the central axis 2001c of the lens plate are aligned, x2 = x3
= X4 = x5, y2 = y3 = y4 = y5, and x2: y
The condensing position (optical axis) of each unit lens may be set at a position of 2 = 4: 3.

FIG. 22 is a diagram for simply explaining the effect of the lens plate 2001, and shows that parallel light is split by the lens plate 2001 and superposed on the irradiation target 2201. As shown in the figure, the parallel light incident on the lens plate 2001 is
By appropriately differentiating the condensing position (optical axis) of each unit lens forming the lens plate, it is divided into the same number of light beams as the number of lenses forming the lens plate 2001, and the divided light beams are superimposed on the irradiation target 2201. can do.

At this time, the focal length of the unit lenses constituting the lens plate 2001 is fi, the lens plate 111 and the irradiation target 2
When the distance to 201 is l, the light incident on the lens plate 2001 in a parallel state and the light passing therethrough is (l of the aperture area of each unit lens forming the lens plate 2001 on the irradiation target 2201.
The light flux has a cross-sectional area of -fi) / fi times. Based on this relationship, the light flux split by the lens plate 2001 can illuminate the display unit of the liquid crystal panel via the condenser lens 104 and the dichroic prism 110 without excess or deficiency, and the focus of each unit lens forming the lens plate 2001. Distance f
i may be determined.

FIG. 23 is a schematic diagram showing the state of light when the parallel output light from the light source section is split by the lens plate 2001 illustrated in FIG. In the figure, the shaded area represents the cross-sectional shape of the light beam divided by the lens plate 2001, and the part where all the four divided light beams are overlapped is shown in white (2301 in the figure). As shown, the lens plate 20
If the amount of deviation of the condensing position (optical axis) of each unit lens constituting 01 is set to the same ratio as the width / height ratio of the display portion of the liquid crystal panel to be irradiated as described above, it is divided by the lens plate 2001. When the light is overlapped on the liquid crystal panel, its overlapping portion 230
1 can have the same rectangular shape as the display portion of the liquid crystal panel.

In this case, since a plurality of light beams obtained by dividing the output light from the light source unit are superposed on each other, the liquid crystal panel can be illuminated with high uniformity. Therefore, the reflected light from the liquid crystal panel also becomes a uniform light with no brightness and color unevenness, and the image projected on the screen through the projection lens is uniform with no illuminance unevenness and color unevenness, and an image with excellent image quality can be obtained. It will be.

In the case of this embodiment as well, as in the above-described embodiments, the folding optical system is off-axis, and only half of the aperture stop of the projection lens can be effectively used to project the light reflected by the liquid crystal panel. . Specifically, for example, when the aperture stop of the projection lens itself has a circular shape with a radius r, the effective aperture stop has a semicircular shape with a radius r, so that the focusing position (optical axis) of the unit lens forming the lens plate is deviated. It is important to set the maximum amount h of h to a size that fits inside this semi-circle. This is because if the amount of deviation of the condensing position (optical axis) of each condensing lens that constitutes the lens plate 2001 is larger than the opening of the effective aperture stop of the projection lens, most of the light reflected by the liquid crystal panel is the projection lens. This is because the image cannot be projected onto the screen, and an image with sufficient brightness cannot be projected on the screen. However, if the maximum deviation of the focusing position (optical axis) of each unit lens that composes the lens plate is set to be smaller than the aperture of the effective aperture diaphragm of the projection lens, the lens plate is divided. After the light flux is reflected by the liquid crystal panel, it is condensed by the condenser lens 104 at different positions on the same plane perpendicular to the principal axis of the reflected light of the liquid crystal panel. These condensing positions (optical axes) are the aperture stop of the projection lens. Since it is inside the opening, there is no concern that the amount of light will be reduced and the amount of light will be reduced.

FIG. 24 shows another embodiment of the lens plate 2001. The condenser lenses 2401a, 2401b, 2401c, and 2401d that form the lens plate 2001 are the lenses 2002 and 20 that form the lens plate shown in FIG.
03, 2004, 2005, but the substantial aperture of each lens is defined in a shape similar to the display portion of the liquid crystal panel by the light shielding means 2402, and these lens aperture portions are the light source portion. Is arranged so as to be inscribed in the sectional shape of the output light from. Shading means 240
2 is a heat-resistant material that can withstand a temperature rise due to the output light from the light source made black so as to absorb visible light, for example, aluminum made black by alumite treatment, or blackened heat-resistant plastic as a lens. It may be realized by sticking or installing in the vicinity of the lens, or may be realized by coloring the lens itself.

In this case, since the cross-sectional shape of each light beam divided by the lens plate can be made equal to the shape of the display portion of the liquid crystal panel, it is possible to superimpose the divided light flux on the display portion of the liquid crystal panel without excess or deficiency. Becomes Therefore, it is possible to reduce unnecessary light to places other than the display section of the liquid crystal panel,
There is an effect that there is no deterioration in image quality such as a decrease in contrast due to stray light.

FIG. 25 shows another embodiment of the lens plate. This lens plate 2001 is a lens 2501 formed by integrally molding four condensing lenses having a shape similar to the display part of the liquid crystal panel, in other words, four different condensing positions (lights) having a shape similar to the display part of the liquid crystal panel. A lens 2501 having an opening having an axis) and a light blocking means 2502. The four openings of the lens 2501 are arranged so as to be inscribed in the effective cross-sectional shape of the output light from the light source section, and the portion outside the lens opening and through which the light from the light source section passes is blocked by the light blocking means 2502. It is shielded from light. As the light blocking means 2502, similar to the lens plate shown in FIG.
Although it may be formed of a surface that absorbs visible light, it may be formed of a reflection surface that is perpendicular to the main axis of the output light from the light source unit. The reflecting surface may be realized by coating a metal film of Al, Ag, or the like on the corresponding portion, or may be realized by coating a dielectric multilayer film.

In this case, of the output light from the light source section, the light reaching the outside of the lens opening section returns to the light source section. Therefore, it is possible to prevent unnecessary light from entering the projection optical system, so that it is possible to prevent deterioration of image quality such as a decrease in contrast ratio due to stray light caused by unnecessary light. Further, the light reflected by the reflecting surface and returned to the light source section is reflected by the reflecting mirror 102 a plurality of times and then comes back to the lens opening section of the lens plate, so that the light originally discarded as unnecessary light can be reused. There is an effect that the utilization efficiency of light can be improved.

26 and 27 show another embodiment of the lens plate 2001. These lens plates also have a configuration in which a plurality of unit lenses are arranged in a plane perpendicular to the main axis of the output light from the light source unit, divide the light emitted from the light source unit into a plurality of light beams, and divide the divided light beams. The focal length and focusing position (optical axis) of each unit lens are specified so that they can be superimposed on the display section of the liquid crystal panel, and the maximum amount of deviation of the focusing position (optical axis) of each unit lens is the effective aperture stop of the projection lens. Is set smaller than the size of.

FIG. 26 shows a lens plate composed of a condenser lens 2601 having 10 openings having a shape similar to the display portion of the liquid crystal panel and a light shielding means 2602.
Is a lens plate composed of a lens 2701 having 18 openings having a shape similar to the display portion of the liquid crystal panel and a light shielding means 2702.

The lens apertures of the lens plate shown in FIGS. 26 and 27 are inscribed in or inside the effective cross-sectional shape of the output light from the light source unit. A portion outside the opening and through which the output light from the light source unit passes is shielded by a light shielding unit. In this case, of the output light from the light source unit, the amount of light blocked by the light blocking unit can be made smaller than that of the lens plate having four openings, so that the utilization efficiency of the output light from the light source unit is improved. . Furthermore, by increasing the number of lens apertures, the individual light beams split by the lens plate become evenly smaller light, and the display on the liquid crystal panel is illuminated more uniformly, so that the image on the screen is This has the effect of producing a more uniform and bright image.

The number of lens openings forming the lens plate is not limited to 4, 10, and 18 used in the above description.

Next, the shape of the aperture of the aperture stop 105 arranged near the focal point of the condenser lens 104 will be described.
Similar to a projection type liquid crystal display device using two lens plates,
Also in the case of a projection type liquid crystal display device using one lens plate, the light beams divided by the lens plate 2001 are incident on the liquid crystal panel at different angles, and the reflected light of the liquid crystal panel is perpendicular to the main axis of the reflected light. The light is focused on a plurality of different positions corresponding to the number of unit lenses on another plane.

FIG. 28 shows the lens plate 2001 as shown in FIGS.
4, a diagram showing an example of a cross-sectional shape of a light beam which is specularly reflected by the liquid crystal panel and is condensed by the condenser lens 104 in the vicinity of the aperture stop 105 when it is composed of four unit lenses as illustrated in FIG. Is. The cross-sectional shape 2801 of the light specularly reflected by the liquid crystal panel and condensed by the condenser lens corresponds to the illuminant image of the light source 101 formed by the lens plate 2001, and is the same as the number of unit lenses constituting the lens plate 2001. The same number of light beams are arranged radially.

Therefore, as in the case where two lens plates are used, the shape of the aperture of the aperture stop 105 is such that the light reflected by the liquid crystal panel and condensed by the condenser lens 104 is properly contained inside. You can do this.

That is, as shown in FIG. 29, an aperture stop having apertures 2901 in which the same number of minute apertures as the number of unit lenses constituting the lens plate are radially arranged, or FIG.
An aperture stop having an opening 3001 having a single radial shape by expanding and fusing these minute openings as shown in FIG.

Also in this case, the light specularly reflected by the liquid crystal panel appropriately passes through the aperture stop, and the light scattered and reflected by the liquid crystal panel is sufficiently absorbed by the aperture stop and does not enter the projection lens. You can obtain a bright image with a higher contrast ratio. Furthermore, since the light emitted from the light source unit is split and the light with small unevenness after splitting is superimposed on the display unit of the liquid crystal panel, uniform illumination is performed on the liquid crystal panel, so there is little unevenness in illuminance and color You can get a quality image.

As described above, if the number of lens plates is one, the number of parts can be reduced.

[0107]

As described above, in the projection type liquid crystal display device of the present invention, because of the effect of the lens plate, it is possible to uniformly illuminate the liquid crystal panel with little brightness and color unevenness.
It is possible to display an image with excellent image quality without unevenness in illuminance and color on the screen. Further, in the projection type liquid crystal display device of the present invention, the shape of the opening of the aperture stop is a shape that is suitable for the cross-sectional shape of the light specularly reflected by the liquid crystal panel when the lens plate is adopted, so that the liquid crystal panel has a positive shape. The reflected light passes through the aperture stop properly, and the light scattered and reflected by the liquid crystal panel is not absorbed by the aperture stop and does not enter the projection lens, so it is brighter on the screen and has a high contrast ratio and high quality. You can get a nice video.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an outline of a projection type liquid crystal display device of the present invention.

FIG. 2 is a schematic view showing an example of a first lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 3 is a schematic view showing an example of a second lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 4 is a schematic view showing an example of a second lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 5 is a schematic sectional view showing an example of a dichroic prism used in the projection type liquid crystal display device of the present invention.

FIG. 6 is a diagram showing a diaphragm surface of a projection lens of the projection type liquid crystal display device of the present invention.

FIG. 7 is a diagram showing an example of a cross-sectional shape of light condensed near an aperture stop in the projection type liquid crystal display device of the present invention.

FIG. 8 is a diagram showing an example of an aperture stop used in the projection type liquid crystal display device of the present invention.

FIG. 9 is a diagram showing an example of an aperture stop used in the projection type liquid crystal display device of the present invention.

FIG. 10 is a schematic view showing an example of a first lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 11 is a diagram showing an example of a cross-sectional shape of light condensed near the aperture stop in the projection type liquid crystal display device of the present invention.

FIG. 12 is a diagram showing an example of an aperture stop used in the projection type liquid crystal display device of the present invention.

FIG. 13 is a diagram showing an example of an aperture stop used in the projection type liquid crystal display device of the present invention.

FIG. 14 is a diagram showing an example of an aperture stop used in the projection type liquid crystal display device of the present invention.

FIG. 15 is a diagram showing a relationship between an aperture area of an aperture stop and a contrast ratio.

FIG. 16 is a diagram showing a relationship between an aperture area of an aperture stop and screen illuminance.

FIG. 17 is a schematic sectional view showing an outline of a projection type liquid crystal display device of the present invention.

FIG. 18 is a diagram showing a projection lens diaphragm surface of the projection type liquid crystal display device of the present invention.

FIG. 19 is a schematic sectional view showing an outline of a projection type liquid crystal display device of the present invention.

FIG. 20 is a schematic sectional view showing an outline of a projection type liquid crystal display device of the present invention.

FIG. 21 is a schematic view showing an example of a lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 22 is a view for explaining a lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 23 is a schematic diagram showing a state in which light beams split by a lens plate used in the projection type liquid crystal display device of the present invention are superimposed.

FIG. 24 is a schematic view showing an example of a lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 25 is a schematic view showing an example of a lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 26 is a schematic view showing an example of a lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 27 is a schematic view showing an example of a lens plate used in the projection type liquid crystal display device of the present invention.

FIG. 28 is a view showing an example of a cross-sectional shape of light condensed near the aperture stop in the projection type liquid crystal display device of the present invention.

FIG. 29 is a diagram showing an example of an aperture stop used in the projection type liquid crystal display device of the present invention.

FIG. 30 is a diagram showing an example of an aperture stop used in the projection type liquid crystal display device of the present invention.

FIG. 31 is a view for explaining the basic operation of a projection type liquid crystal display device using a reflection / scattering type liquid crystal panel.

[Explanation of symbols]

101 ... Light source, 102 ... Reflecting mirror, 103 ... Filter, 1
04 ... Condensing lens, 105 ... Aperture stop, 106 ... Micro-reflecting mirror, 107 ... Blue reflection / scattering liquid crystal panel, 108 ...
Reflective / scattering liquid crystal panel for green, 109 ... Reflective / scattering liquid crystal panel for red, 110 ... Dichroic prism, 11
DESCRIPTION OF SYMBOLS 1 ... Projection lens, 112 ... Screen, 201 ... 1st lens plate, 301 ... 2nd lens plate, 801 ... Aperture stop aperture part, 802 ... Aperture stop light-shielding absorption part, 2001 ... Lens plate.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Matsuda, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa, Ltd. Information & Video Division, Hitachi, Ltd.

Claims (5)

[Claims] 1. A light source section, a condenser lens that collects light from the light source section, a reflection-scattering liquid crystal panel to which the light collected by the condenser lens is irradiated, and modulation by the reflection-scattering liquid crystal panel. Projection-type liquid crystal having a projection lens for projecting the projected light through the condensing lens, an aperture stop located between the condensing lens and the projection lens, and a screen onto which the projected light is projected. A display device, comprising two lens plates each composed of a plurality of unit lenses between the light source unit and the condenser lens, the lens plate being arranged at a position close to the condenser lens. The lens plate is arranged at a position having substantially the same optical distance as the aperture stop as viewed from the reflection-scattering type liquid crystal panel, and the size of the lens aperture of the lens plate is smaller than the size of the aperture stop. Projection type liquid Crystal display device. 2. A light source section, a condenser lens that collects light from the light source section, a reflection-scattering type liquid crystal panel to which the light collected by the condenser lens is irradiated, and modulation by the reflection-scattering type liquid crystal panel. Projection-type liquid crystal having a projection lens for projecting the projected light through the condensing lens, an aperture stop located between the condensing lens and the projection lens, and a screen onto which the projected light is projected. In the display device, between the light source unit and the condenser lens, one lens plate having a plurality of lenses arranged in a plane perpendicular to the main axis of the output light from the light source unit is arranged, The lens plate has an optical axis at a position where all of the individual unit lenses forming the lens plate are different, and the maximum amount of deviation of the optical axes of these unit lenses is the maximum of the aperture stop of the projection lens system. Throw characterized by being smaller than size Type liquid crystal display device. 3. The projection type liquid crystal display device according to claim 2, wherein the aspect ratio of the amount of deviation of the optical axis of each lens forming the lens plate is defined by the width of the display section of the reflection-scattering type liquid crystal panel. The projection-type liquid crystal display device is characterized by having the same ratio of height to height. 4. A light source section, a condenser lens that collects light from the light source section, a reflection-scattering type liquid crystal panel to which the light collected by the condenser lens is irradiated, and modulation by the reflection-scattering type liquid crystal panel. Projection-type liquid crystal having a projection lens for projecting the projected light through the condensing lens, an aperture stop located between the condensing lens and the projection lens, and a screen onto which the projected light is projected. In the display device, between the light source unit and the condenser lens, at least one lens plate having a plurality of unit lenses arranged in a plane perpendicular to the main axis of the output light from the light source unit is provided. A shape in which minute apertures of the same number as or proportional to the number of unit lenses constituting one lens plate in which the aperture of the aperture stop is arranged at a position closest to the condenser lens are radially arranged, or the minute Widen the opening Projection-type liquid crystal display device, characterized in that the microscopic aperture between fused shape, or a single radial shape that combines all of the small openings widen the microscopic aperture. 5. A light source section, a condenser lens that collects light from the light source section, a reflection-scattering liquid crystal panel that is irradiated with the light collected by the condenser lens, and modulation is performed by the reflection-scattering liquid crystal panel. Projection-type liquid crystal having a projection lens for projecting the projected light through the condensing lens, an aperture stop located between the condensing lens and the projection lens, and a screen onto which the projected light is projected. A display device, comprising at least one lens plate having a configuration in which a plurality of unit lenses are arranged in a plane perpendicular to a main axis of output light from the light source unit, between the light source unit and the condenser lens. The opening shape of the unit lens forming the lens plate disposed closest to the light source unit among the lens plates is similar to the display unit of the reflection-scattering type liquid crystal panel, and each lens opening is Part from the light source part Inscribed in the cross-sectional shape of the output light of
Alternatively, the projection type liquid crystal display device is arranged so as to fit inside the cross-sectional shape of the output light.