JP2982990B2 - Display device and optical unit - Google Patents

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 and the like.
More particularly, the present invention relates to a technique suitable for obtaining a bright projected image by increasing the light output from a display element such as a liquid crystal element by increasing the efficiency of using light from a light source.

[0002]

2. Description of the Related Art A conventional display device, for example, a projection type liquid crystal display device is disclosed in JP-A-63-15225 and JP-A-63-1.
As described in Japanese Patent No. 16123, white light output from a single light source is converted by a dichroic mirror.
By splitting the light into the three primary colors of red, blue, and green, and entering the three primary colors into three liquid crystal light valves, an image corresponding to the three primary colors is synthesized using a dichroic mirror or a dichroic prism. ,
A color image was obtained, and this color image was enlarged and projected on a screen using a single projection lens.

[0003]

In the above prior art, the structure of each liquid crystal display element used as a light valve is usually optically sandwiched between two polarizing plates.
As a result, the light incident on the liquid crystal display element emits only one of the S-polarized light and the P-polarized light. That is, even if it is assumed that there is no loss, the amount of light transmitted through the liquid crystal element is only one of these two types of polarized light, and thus is half of the light source, and the light use efficiency is reduced by half. Here, the P-polarized light means linearly polarized light having a plane of polarization parallel to the plane of incidence (the plane on which the electric vector oscillates), and the S-polarized light is polarized perpendicular to the plane of incidence. It refers to linearly polarized light having a surface.

Further, it has been pointed out that the above prior art has a problem of an aperture ratio of a liquid crystal display element. Here, the aperture ratio is defined as follows. Aperture ratio = effective area contributing to display in one pixel / area of one pixel entire region. That is, if a portion that does not contribute to display is large, the aperture ratio becomes small, and light use efficiency deteriorates. Examples of the portion that does not contribute to display (referred to as a light blocking portion) include a metal wiring of each electrode, a non-linear element or a switching element added as a means for individually controlling each pixel, a gap around a pixel electrode, and the like.

Further, in order to increase the definition with the same liquid crystal display element panel size, it is necessary to reduce the pixel pitch. In this case, if all the constituent elements of the liquid crystal display element can be reduced in a similar manner, the aperture ratio is reduced. Does not change, but the width of the metal wiring of the electrode and the size of the additional element cannot be reduced below a certain level in terms of etching accuracy and alignment accuracy.
As a result, there is a problem that as the definition is increased, the aperture ratio is necessarily reduced.

Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art. The first object of the present invention is to provide not only S-polarized light (or P-polarized light) but also P-polarized light (or S-polarized light). the techniques) can obtain a bright image be used to enable, and further a second object of the present invention, larger the aperture ratio,
It is an object of the present invention to provide a technique capable of obtaining a bright image by greatly improving light use efficiency.

[0007]

The object of the present invention is achieved.
Therefore, in the first aspect, the display device converts the incident light into P-polarized light.
Separating means for separating light and s-polarized light;
To convert one of the polarized lights into P-polarized light or S-polarized light.
Replacement means and a plurality of lens units are arranged corresponding to each pixel.
A display element having a microlens array and an image signal
And a circuit section for driving the display element based on the
The other polarized light obtained from the means and the one polarized light are
The polarized light obtained by the conversion by the conversion means is
The same pixel is illuminated through the lens part of the micro lens array.
And is configured to display an image. In the second invention
The display device separates incident light into P-polarized light and S-polarized light.
Separating means for separating one of the two polarized lights into P-polarized light.
Converting means for converting the light into light or S-polarized light;
The micro lens array where the
Having a display element and driving the display element based on an image signal
And a circuit portion, which is obtained from the separation means.
The polarized light and the one polarized light are converted by the conversion means.
And the polarized light obtained through
To the corresponding pixel through the same lens part of the lens array
It is configured to irradiate and display an image . Third invention
Then, the display device separates the incident light into P-polarized light and S-polarized light.
Separating means, and one of the two polarized lights is referred to as P
Conversion means for converting the light into polarized light or S-polarized light;
Lens portion is arranged corresponding to the pixel, and the shape of the lens portion is
The same microlens array as the shape of the area corresponding to the pixel
A display element having
A driving circuit section, and the
One polarized light and the one polarized light are converted by the conversion means.
And the polarized light obtained by the
Irradiates the same pixel through the lens section of
It is configured as follows . In the third aspect of the present invention,
The micro lens array has a square or lens shape.
It may be rectangular. In the fourth invention, the display device is an input device.
Separating means for separating the emitted light into P-polarized light and S-polarized light;
One of the polarized lights is P-polarized light or S-polarized light
And conversion means for converting a plurality of lens portions corresponds to a pixel
And the lens portion has a square or rectangular shape.
A display element having an microlens array, and a
And a circuit unit for driving the display element.
The other polarized light obtained from the stage and the one polarized light are
The polarized light obtained by conversion by the conversion means is
Illuminates the same pixel through the lens section of the Chlorens array
It is configured to display an image . In the fifth invention
The optical unit separates the incident light into P-polarized light and S-polarized light.
Separating means for separating, and one of the two polarized lights
Converting means for converting the light into P-polarized light or S-polarized light;
Microlens array with lens section corresponding to the pixel
And a display element having
The other polarized light and the one polarized light are converted by the conversion means.
The polarized light obtained by the conversion, through a polarizing plate and the above
Through the lens section of the micro lens array to the same pixel
It is configured to irradiate . In the sixth invention, an optical unit is provided.
The splitter separates incident light into P-polarized light and S-polarized light.
A step, and converting one of the two polarized lights into a P-polarized light or
Is composed of a conversion means for converting to S-polarized light and a plurality of lens units.
And the shape of the lens part corresponds to the pixel
Having the same micro lens array as the shape of the area
A display element, and the other bias obtained from the separation means.
The light light and the one polarized light are converted by the conversion means.
The obtained polarized light is passed through the lens of the microlens array.
The same pixel is irradiated through the pixel portion .
In the sixth aspect, the microlens array
May have a square or rectangular lens section.
No. In the seventh invention, the optical unit converts the incident light into P-polarized light.
Separating means for separating light and s-polarized light;
To convert one of the polarized lights into P-polarized light or S-polarized light.
Replacement means and a plurality of lens portions are arranged corresponding to the pixels; and
A micro lens having a square or rectangular shape of the lens portion
A display element having an array.
The other polarized light and the one polarized light are converted by the conversion means.
The polarized light obtained by the conversion in the step is
Illuminate the same pixel through the lens part of the
It is composed of

[0008]

[0009]

[0010]

[0011]

[0012]

[0013]

The separating means converts incident light into P-polarized light and S-polarized light.
To separate. The above conversion means is used when P-polarized light is incident.
Is when the P-polarized light is converted to the S-polarized light and the S-polarized light is incident.
Converts the S-polarized light into P-polarized light. The above microre
Lens array focuses incident light and illuminates the pixels of the display device.
You. The circuit unit drives a display element based on an image signal.
Signal.

[0014]

[0015]

An embodiment of the present invention will be described below with reference to the drawings. Example 1 FIG. 1 is a schematic diagram showing the entire configuration of a projection type liquid crystal display device according to one embodiment of the present invention, FIG. 2 is a configuration diagram of a polarization combining element showing a polarization optical system, and FIG. Construct a polarization combining element
FIG. 5 is an explanatory diagram of an operation of the eccentric lens .

In FIG. 1, reference numeral 1 denotes a light source, for example, a white light source such as a metal halide lamp and a halogen lamp. 2 is a reflector, 3 is a focusing lens group for focusing white light from the light source 1, and 4 is a polarization combining element, which will be described in detail later with reference to FIG. -Muscle splitter- and a right-angle prism and a decentered lens as combining means. Reference numeral 5 denotes a liquid crystal display element, which will be described in detail later with reference to FIG. 4, and includes a liquid crystal panel, a polarizing plate, and a flat microlens array. Reference numeral 6 denotes a projection lens for enlarging a display image on the liquid crystal display element 5, and reference numeral 7 denotes a screen. On the other hand, 8 is a video chroma processing circuit as a driving circuit of the liquid crystal display element 5, 9 is an RGB output circuit, 10 is an X driver, 11 is a synchronization processing circuit, 12 is a controller, 13
Is a Y driver.

Further, as shown in FIG. 2, the polarization combining element 4 comprises a polarization beam splitter 14, two right-angle prisms 15 and two decentering lenses 16.

Hereinafter, the operation of this embodiment will be described with reference to FIGS.
This will be described in detail with reference to FIG. In FIG. 1, by providing the light source 1 near the focal point of the reflector-2 (here, parabolic), the light emitted from the reflector-2 becomes a substantially parallel light beam and enters the focusing lens group 3. Focusing lens group 3
Here, the condenser lens 3a having positive power and the negative power
With the condensing lens 3b having the above, the incident light beam is focused while maintaining the parallel light beam to a size of about の of the display area of the liquid crystal display element 5, and is incident on the polarization combining element 4. In this embodiment, a liquid crystal panel equivalent to 1.3 inches is used as the liquid crystal display element 5, and the luminous flux emitted from the condenser lens group 3 is narrowed down to about φ23 mm.

Next, the operation of the polarization combining element 4 will be described with reference to FIG. In the figure, a light beam 17 emitted from a converging lens group 3 (not shown) is an irregularly polarized light beam 18, and is a polarization beam splitter which is a component of the polarization combining element 4.
14 (in this embodiment, 15 mm × 15 mm), and the polarized beam splitter 14 separates the irregularly polarized light 18 into linearly polarized light of S-polarized light 20 (reflected light) and P-polarized light 19 (transmitted light). I do. The separated P-polarized light 19 is further polarized.
The light is magnified about twice by the center lens 16 and is incident on a liquid crystal display element (not shown).

The path of one S-polarized light 20 is bent by 90 ° by two right-angle prisms 15 arranged such that the reflection surfaces are arranged in a state of being inclined at 45 degrees on optical axes orthogonal to each other. While being reflected twice, it is converted into P-polarized light 21 and emitted, expanded about twice by the eccentric lens 16, and enters a liquid crystal display element (not shown). That is, in FIG. 2, one S-polarized light 20 is converted to P-polarized light.
The state converted into light 21 is shown. This allows the optical axis
Different adjacent surfaces, ie, polarizing beam splitter
-The same polarized light from the surface and the right-angle prism surface
A light beam in each direction (P-polarized light 19, 21) is obtained. Next
From the polarizing beam splitter surface and the right-angle prism surface
Eccentricity of the outgoing light beam with its optical axis decentered by a predetermined amount
The light enters the lens 16. Then, the eccentric lens 16
To correct the optical axis deviation of the light beams emitted from the two surfaces,
Magnify twice so that they fit on the surface of the liquid crystal display element.
Shoot. As a result, all the light beams from the light source 1
It can be incident on the liquid crystal display element 5 as a polarized light beam.
Small polarized light that can improve the effective utilization of light nearly twice
A composite element 4 is obtained. Further, the incident side of the liquid crystal display element 5
A flat microlens array on a transparent substrate
With this configuration, incident light can be effectively
To control the metal wiring of each electrode and each pixel individually.
Non-linear element or switch added as a means of
Display elements such as gaps around pixel elements and pixel electrodes.
Loss of incident light due to being blocked by a dark part (light-shielding part)
Almost no doubling, so the aperture ratio can be improved
Wear. As a result, the polarization combining element 4 and the flat microlens
Projection-type liquid crystal display device using a pixel array
Can be obtained.

Next, the operation of the eccentric lens 16 will be described with reference to FIG. FIG. 3A shows a state in which the exit surface side of the polarization combining element 4 shown in FIG. 2 is viewed from the liquid crystal display element side. As described above, the exit surface from the polarization combining element 4 exits from the exit surface 22 from the illustrated polarization beam splitter and the exit surface 23 from the right-angle prism. This 2
The decentered lenses 16 are arranged on the exit surfaces (22, 23) from the surfaces as shown in FIG. Further eccentricity
As shown by the dotted line in FIG. 3, the diameter of the lens 16 has a diagonal length D (21.2 m in this embodiment) of each emission surface (22, 23).
m), a part of the plano-concave lens 25 which becomes 2D is cut out in accordance with the eccentricity of each of the exit surfaces (22, 23) as shown in the figure, and the focal point is set so that the magnification is about twice. Set the distance. FIG. 3B shows an example in which the eccentric lens 16 is divided into four parts from the plano-concave lens 25.
As a result, the enlarged image of the exit surface 22 of the polarizing beam splitter by the eccentric lens 16 is represented by an area 24 indicated by a dashed line.
Further, the enlarged image of the exit surface 23 of the right-angle prism by the other eccentric lens 16 is also a region 2 indicated by a dashed line.
It becomes 4, and the same polarized light is matched and synthesized. The combined area 24 indicated by a dashed line is the same as the display area of the liquid crystal display element 5 in FIG. 1 and is incident on this position so as to be the liquid crystal surface of the liquid crystal display element 5. Here, if the magnification of the eccentric lens 16 is made larger than twice, the magnified image 24 becomes larger than the display area of the liquid crystal display element 5, and the light utilization rate is greatly reduced. If the magnification is smaller than twice, the magnified image 24 becomes smaller than the display area of the liquid crystal display element 5 and uneven brightness occurs. Therefore, it is a feature of the present invention to set the magnification of the eccentric lens 16 to about twice as described above.

As described above, the polarization combining element 4 of this embodiment
By using P, both the P-polarized light and the S-polarized light can be used effectively, so that the deterioration of the light utilization factor depending on the conventional polarizing plate is greatly improved.

Next, the operation of the liquid crystal display element 5 will be described with reference to FIGS. FIG. 4 is a perspective view showing an example of the liquid crystal display element 5, and FIG. 5 is a plan view schematically showing the positional relationship of the components in FIG. In FIG. 4, reference numeral 26 denotes a pair of transparent substrates, one of which is a transparent substrate 26a.
Are provided with a transparent counter electrode 27 on the opposite surface side, and a transparent pixel electrode 29 is provided on the opposite surface side of the other transparent substrate 26b.
Liquid crystal 28 is sealed between 6b. Reference numeral 30 denotes a display formed by metal wiring of each electrode provided on the other transparent substrate 26b, a non-linear element or switching element added as means for individually controlling each pixel, a gap around the pixel electrode, and the like. (Light shielding portion) which does not contribute to
Thus, the liquid crystal panel has a transparent substrate 26, a counter electrode 27,
The liquid crystal device includes a liquid crystal, a pixel electrode 29, and a light shielding unit 30. Reference numeral 31 denotes a flat plate microlens array, which is a feature of the present invention and is a refractive index distribution type lens array having a two-dimensional array provided substantially corresponding to a pixel electrode 29 as shown by a broken line in the figure. It is. Reference numeral 32 denotes a polarizing plate provided outside the flat microlens array 31 and the transparent substrate 26, respectively. The flat microlens array 31 is always provided on the side of the incident light 33 with respect to the liquid crystal 28.

Next, the positional relationship and shape of the preferred components of the present invention will be described with reference to FIG. 4, a hatched area 35 is an area corresponding to one pixel in the liquid crystal 28 in FIG. Then, in the solid line frame 29 in the hatched area
Are pixel electrodes effective for display (that is, light is transmitted), and the other edges are light-shielding portions 30 such as metal wirings and switching elements. The dotted frame 31a in the figure indicates the individual lens shape of the micro lens array 31.

In the present invention, as shown in the drawing, each lens shape of the flat microlens array 31 is made to have the same shape and the same arrangement as the shape of the area 35 corresponding to one pixel in the liquid crystal 28. Is preferred. Next, the operation of the flat microlens array 31 will be described with reference to FIG. FIG. 6 is a sectional view of a main part of FIG. In FIG. 6, reference numeral 36 denotes an individual refractive index distribution region (lens portion) of the flat microlens array 31. The refractive index distribution region 36 may be provided on either side of the flat microlens array 31 as shown in the figure. Further, by adjusting the refractive index distribution region 36, the focal point is set so as to be on or near the surface of the liquid crystal 28. Thereby, the incident light beam 33 parallel to the optical axis that has passed through the polarizing plate (not shown) is converged by the flat-plate microlens array 31 and does not pass through the light-shielding portion 30 such as a metal wiring or a switching element. That is, since the light enters the opening, the deterioration of the light utilization rate depending on the conventional aperture ratio is greatly improved. That is, usually 40%
, Which is twice as high as 80%.

The functions and effects of the polarization synthesizing element 4 and the flat microlens array 31 have been individually described above. Next, these are combined to simultaneously improve the deterioration of the light utilization rate depending on the polarizing plate and the aperture ratio. The conditions for performing this will be described with reference to FIGS. 7, 8, and 9. FIG.

FIG. 7 shows the relationship between the optical axis of the polarization beam splitter 14 of the polarization beam splitter 4 shown in FIG. 2 and the optical axis of the right-angle prism 15. Reference numeral 37 denotes a polarization beam splitter. An optical axis 14 and an optical axis 38 of the right-angle prism 15 are shown. (A) of the same figure is a diagram of the polarization combining element 4 viewed from the side,
(B) has shown the figure seen from the front. In the polarization combining element 4 of this embodiment, as shown in FIG. 7, the polarization beam splitter optical axis 37 and the right-angle prism optical axis 38 are decentered by a predetermined amount. Act as if there are two from the lens group to the focusing lens group 3. Hereinafter, the light source 1 indicated by the solid line to the focusing lens group 3 is referred to as a first light source, and the light source 1 indicated by the dotted line to the focusing lens group 3 is referred to as a second light source. Accordingly, the light emitted from either the first light source or the second light source is incident on the same opening by the flat microlens array 31 shown in FIG. The degradation of the utilization rate can be improved at the same time.
The brightness of 2 times with a microlens + 2 times with a polarization combining element) can be obtained.

Hereinafter, conditions for improving both the polarization plate 32 and the deterioration of the light utilization rate due to the aperture ratio will be described with reference to FIGS. FIG. 8 shows an optical relationship among the first light source, the second light source, and the flat microlens array. 8, reference numeral 39 denotes an optical axis of one lens of the flat microlens array 31, reference numeral 40 denotes a first light source, and reference numeral 41 denotes a second light source. Each of the light sources 1 obtained by the focusing lens group 3 and the eccentric lens 16 is used. It is a statue. FIG. 3A is a side view of one of a pixel electrode 29 formed on a transparent substrate 26b of the liquid crystal display element 5 and a light shielding portion 30 surrounding the pixel electrode 29, and FIG. FIG. 42 is a flat plate micro lens array 31
And 43 is an image of the second light source 41 obtained by the flat microlens array 31. As shown in FIG. 8, the first light source image 42 and the second light source image 43 are also decentered with the decentering of the optical axis 37 of the polarizing beam splitter 14 and the optical axis 38 of the right angle prism 15. In order to improve the aperture ratio, it is desirable that both the first light source image and the second light source image be formed in the pixel electrode 29 of the liquid crystal display element 4, and the first light source image 42 and the second light source image 43 It must be smaller than the eccentricity of the size of the pixel electrode 29.

As shown in FIG. 8, the eccentricity of the first light source 40 and the second light source 41 is δ1, the eccentricity of the first light source image 42 and the second light source image 43 is δ2, The distance to the microlens array 31 is defined as L, and the focal length of the flat microlens array 31 is defined as f. Here, the first
As shown in FIG. 3, the eccentricity of the light source 40 and the second light source 41 is eccentricity between the polarizing beam splitter-outgoing surface 22 and the rectangular prism outgoing surface 23, so that δ1 is the polarizing beam splitter. Is equal to the diagonal length D. For example, polarized beams
If a size of 15 × 15 mm is applied to the muscle splitter 14, δ1 = 21.2 (= 15√2). Further, since L 通常 δ1 is usually satisfied, the first light source 40 and the second light source 4
1 are substantially equal, and the eccentricity δ2 of the first light source image 42 and the second light source image 43 is represented by δ2 = 2δ1 · f / L.

Assuming that the diagonal length of the pixel electrode 29 is y1, to improve the aperture ratio, the first light source image 42 and the second light source image 43
The amount of eccentricity δ2 must be smaller than y1,
It is desirable that the length be less than about １ ／ of the diagonal length y1 of the pixel electrode 29.

The embodiment described above with reference to FIG.
Although both the second and second light source images 43 are conditions for forming an image in one pixel electrode 29, the respective light source images are formed on two pixel electrodes 29 which are diagonally adjacent to each other. Similar effects can be obtained in the case of imaging. That is, FIG. 9 shows such an example, and it is desirable that the amount of eccentricity δ2 be close to the distance y between the pixel electrodes 29 adjacent to each other in the diagonal direction.

As described above, in order to simultaneously improve the deterioration of the light utilization rate depending on the polarizing plate 32 and the aperture ratio,
Eccentricity δ1 of the first light source 40 and the second light source 41, the eccentric amount δ2 of the first light source image 42 and the second light source image 43, the distance from the first light source 40 to the planar microlens array 31 L, planar microlens array 31 Must be set optimally.

Further, as shown in FIG.
Is enlarged by the projection lens 6 to obtain an enlarged image on the screen 7. A drive circuit for the liquid crystal display element 5 is, for example, a circuit block shown in FIG. 1. The video input from a laser disk, a VTR or the like is processed by a video chroma processing circuit 8, and an RGB output circuit is provided. 9 is input. The RGB output circuit 9 inverts the polarity every vertical period in order to AC drive the video signals corresponding to R, G, B and the liquid crystal display element 5,
The signal is input to the electrodes of the liquid crystal display element 5 via the X driver 10. The video chroma processing circuit 8, RGB output circuit 9, X driver 10 and Y driver 13 are synchronized by a synchronization processing circuit 11 and a controller 12.

As described above, in the present embodiment, only the linearly polarized light in one direction is used among the indefinitely polarized light from the light source 1 in the present embodiment. Almost all of the indefinitely polarized light can be effectively used, and the effective aperture ratio of the liquid crystal display element 5 is improved by the flat microlens 31.
The effective utilization of light is greatly improved, and a bright projection type liquid crystal display device can be obtained.

The above embodiment shows a case in which one liquid crystal display element 5 is used as a light valve. Therefore, in the case of color display, a color not shown in the liquid crystal display element 5 is used. -Naturally, it is necessary to provide a filter. Further, the embodiment described above is a so-called color 3
The present invention can also be applied to a method using three liquid crystal display elements 5 corresponding to the primary colors (R, G, B). This will be described in detail in the second embodiment.

<Embodiment 2> FIG. 10 is a schematic structural view showing a second embodiment of the projection type liquid crystal display device of the present invention. In the figure, parts corresponding to those in FIG.
The detailed description is omitted. By providing the light source 1 near the focal point of the reflector-2 (here, parabolic),
The light emitted from the reflector-2 becomes a substantially parallel light beam and enters the condenser lens group 3. In the focusing lens group 3, the incident light beam is converted into a parallel light beam having a size of about の of the display area of the liquid crystal display element 5 by the condenser lens 3 a having positive power and the condenser lens 3 b having negative power. The light is converged while being maintained and enters the polarization combining element 4.

In the polarization combining element 4, as described with reference to FIGS. 2 and 3, the non-uniform polarized light of the light source 1 is converted into a polarized beam splitter.
At 14, the light is separated into linearly polarized light in two directions, S-polarized light 20 and P-polarized light 19, and either polarized light is converted into the other polarized light by two right-angle prisms 15, and a polarized beam splitter is used. The same polarized light is emitted from two surfaces from −14 and the right-angle prism 15. This is approximately doubled by the eccentric lens 16, and each of the RGB liquid crystal display elements (5R, 5G,
5B) The light is emitted from the polarization conversion element 4 so as to be synthesized on the plane. The light beam emitted from the polarization combining element 4 is a total reflection mirror arranged at an angle of 45 ° with respect to the optical axis of the light beam.
The path is bent by 90 ° by 44, and further enters a BR reflection dichroic mirror 45 that reflects B (blue) and R (red) arranged at an angle of 45 ° with respect to the optical axis of this light beam, B and R are reflected and G (green) is transmitted. The B and R reflected by the BR reflecting dichroic mirror 45 are reflected by the R reflecting dichroic mirror 4 which reflects only the R arranged at an angle of 45 ° with respect to the optical axis of this light beam.
6, R is reflected by an R reflection dichroic mirror 46, passes through a correction lens 47, and then the R liquid crystal display element 5.
Irradiate R. B is an R reflection dichroic mirror.
After passing through the correction lens 47, the liquid crystal display element 5B for B is irradiated. On the other hand, the G transmitted through the BR reflection dichroic mirror 45 has its path bent by 90 ° by the total reflection mirror 44 arranged at an angle of 45 ° with respect to the optical axis of this light beam, and the correction lens 47 is After passing through, the liquid crystal display element 5G for G is irradiated. And R, G,
Images corresponding to each of B are obtained separately.

Further, R emitted from the R liquid crystal display element 5R reflects an R reflection dichroic mirror 46 which reflects R disposed at an angle of 45 ° with respect to the optical axis of the light, and this R RG reflecting dichroic mirror 48 for reflecting R and G arranged at an angle of 45 ° with respect to the optical axis of
And is incident on the projection lens 6. G emitted from the G liquid crystal display element 5G is positioned at 45 ° with respect to the optical axis of this light beam.
Through the R-reflecting mirror 46 arranged at an angle of
The light is reflected by the RG reflecting dichroic mirror 48 arranged at an angle of 45 ° with respect to the optical axis of
Is incident on the projection lens 6. B emitted from the liquid crystal display element 5B for B is at 45 ° with respect to the optical axis of this light beam.
Is reflected by the path reflected at 90 ° by the total reflection mirror 44 disposed at an angle of .theta. And further transmitted through the RG reflection dichroic mirror 48, and is incident on the projection lens 6 in the same manner as the R and G. . And each liquid crystal display element 5
Images displayed on R, 5G, and 5B are enlarged by the projection lens 6 to obtain an enlarged image on the screen 7. Here, the optical axes of R, G, and B that radiate from each liquid crystal display element 5 and irradiate the projection lens 6 coincide with each other, and further, the distance from each liquid crystal display element to the projection lens 6 coincides. Therefore, an enlarged image of a color in which R, G, and B are combined is obtained on the screen 7.

In this embodiment, the description has been given of the case where the polarization combining element 4 is used in a liquid crystal display device. However, it is also possible to use the polarization combining element 4 in equipment using polarized light and its applied products. Needless to say, there is.

[0040]

According to the present invention, it is possible to effectively irradiate the display element as a polarized light beam by converting the light from the light source, which has been absorbed by the polarizing plate, more than half of the light, in the past. Further, the effective aperture ratio of the liquid crystal panel can be increased by the flat microlens array, so that the effective light utilization rate can be greatly improved.
A liquid crystal display device with a bright screen can be realized.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a schematic configuration diagram of a polarization combining element.

FIG. 3 is an eccentric lens which is also a component of the polarization combining element.
Explanatory view showing the action of the figure.

FIG. 4 is a perspective view of the same liquid crystal display element.

FIG. 5 is a surface view of the same liquid crystal display element.

FIG. 6 is a sectional view of a main part of the liquid crystal display element.

FIG. 7 is a configuration diagram showing a relationship between a polarization combining element and a light source.

FIG. 8 is a configuration diagram showing the operation of a polarization combining element and a flat microlens.

FIG. 9 is a configuration diagram showing the operation of a polarization combining element and a flat microlens.

FIG. 10 is a schematic configuration diagram of a liquid crystal display device according to another embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Light source, 2 ... Reflector, 3 ... Focusing lens group, 4 ... Polarization combining element, 5 ... Liquid crystal display element, 6 ... Projection lens , 7 ...
Screen, 8: Video chroma processing circuit, 9: RGB output circuit, 10: X driver, 11: Synchronous processing circuit, 12
... Controller, 13 ... Y driver, 14 ... Polarization beam splitter, 15 ... Right angle prism, 16 ... Eccentric lens
'S, 17 ... light, 18 ... indefinite polarized light, 19, 21 ... P-polarized light, 20 ... S-polarized light, 22 ... a polarizing - beam splitter -
Emission surface, 23 ... Right angle prism emission surface, 24 ... Enlarged image, 2
5 ... plano-concave lens, 26 ... transparent substrate, 27 ... counter electrode, 2
Reference numeral 8: liquid crystal, 29: pixel electrode, 30: light shielding portion, 31: flat microlens array, 32: polarizing plate, 33: incident light beam, 34: outgoing light beam, 35: area corresponding to one pixel, 3
6 ... refractive index distribution area, 37 ... polarizing beam splitter optical axis, 38 ... right angle prism optical axis, 39 ... lens optical axis, 40
... 1st light source, 41 ... 2nd light source, 42 ... 1st light source image, 43
.. A second light source image, 44 a total reflection mirror, 45 a BG reflection dichroic mirror, 46 a R reflection dichroic mirror, 47 a correction lens, and 48 a RG reflection dichroic mirror.

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaharu Exit 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside Hitachi, Ltd. Visual Media Research Laboratory (72) Inventor Takesuke Maruyama 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa (56) References JP-A-4-78816 (JP, A) JP-A-4-63318 (JP, A) JP-A-4-88317 (JP, A) (58) Survey Field (Int.Cl. ⁶ , DB name) G02B 27/28 G02F 1/13 505 G02F 1/1347 G03B 33/12 H04N 5/74

Claims (9)

(57) [Claims] An apparatus for separating incident light into P-polarized light and S-polarized light.
Separating means, and converting one of the two polarized lights into a P-polarized light.
Or a conversion unit for converting to S-polarized light, and a plurality of lens units
Has a micro lens array arranged corresponding to each pixel.
And a display element to be driven based on an image signal.
Circuit part, and the other bias obtained from the separation means.
The light light and the one polarized light are converted by the conversion means.
The obtained polarized light is passed through the lens of the microlens array.
Irradiate the same pixel through
A display device, comprising: 2. An apparatus for separating incident light into P-polarized light and S-polarized light.
Separating means, and converting one of the two polarized lights into a P-polarized light.
Or a conversion unit for converting to S-polarized light, and a plurality of lens units
Has a micro lens array arranged corresponding to the pixels
And the display element is driven based on the image signal.
Circuit part, and the other polarized light obtained from the separation means.
The light and the one polarized light are converted by the conversion means.
Polarized light through a polarizing plate and the microlens
The corresponding pixels through the same lens of the array
And a display device for displaying images.
Place . 3. An apparatus for separating incident light into P-polarized light and S-polarized light.
Separating means, and converting one of the two polarized lights into a P-polarized light.
Or a conversion unit for converting to S-polarized light, and a plurality of lens units
Are arranged corresponding to the pixels, and the shape of the lens portion is
Has the same microlens array as the shape of the corresponding area
And a display element to be driven based on an image signal.
Circuit part, and the other bias obtained from the separation means.
The light light and the one polarized light are converted by the conversion means.
The obtained polarized light is passed through the lens of the microlens array.
Irradiate the same pixel through
A display device, comprising: 4. The micro lens array according to claim 1 , wherein
4. The display device according to claim 3, wherein the shape is a square or a rectangle.
Place . 5. An apparatus for separating incident light into P-polarized light and S-polarized light.
Separating means, and converting one of the two polarized lights into a P-polarized light.
Or a conversion unit for converting to S-polarized light, and a plurality of lens units
Are arranged corresponding to the pixels, and the shape of the lens portion is square.
Or display element having rectangular microlens array
And a circuit unit for driving the display element based on the image signal.
The other polarized light obtained from the separating means,
Polarized light obtained by converting one polarized light by the converting means
Light is transmitted through the lens section of the micro lens array
Irradiating the same pixel to display an image
Characteristic display device . 6. A component for separating incident light into P-polarized light and S-polarized light.
Separating means, and converting one of the two polarized lights into a P-polarized light.
Or a conversion unit for converting to S-polarized light, and a plurality of lens units
Has a micro lens array arranged corresponding to the pixels
Display element, and the other obtained from the separation means.
The polarized light and the one polarized light are converted by the conversion means.
And the polarized light obtained through
Illuminates the same pixel through the lens part of the lens array
An optical unit having a configuration as described above . 7. An apparatus for separating incident light into P-polarized light and S-polarized light.
Separating means, and converting one of the two polarized lights into a P-polarized light.
Or a conversion unit for converting to S-polarized light, and a plurality of lens units
Are arranged corresponding to the pixels, and the shape of the lens portion is
Has the same microlens array as the shape of the corresponding area
And a display element to be obtained from the separation means.
Polarized light and the one polarized light are converted by the conversion means.
Of the microlens array
A configuration that irradiates the same pixel through the lens unit
An optical unit characterized by the above-mentioned . 8. The microlens array according to claim 1 , wherein
The optical unit according to claim 7, wherein the shape is a square or a rectangle.
Knit . 9. An apparatus for separating incident light into P-polarized light and S-polarized light.
Separating means, and converting one of the two polarized lights into a P-polarized light.
Or a conversion unit for converting to S-polarized light, and a plurality of lens units
Are arranged corresponding to the pixels, and the shape of the lens portion is square.
Or a display element having a rectangular microlens array
And the other polarized light obtained from the separating means,
The polarized light obtained by converting one of the polarized lights by the conversion means.
Light and light through the lens section of the micro lens array
Light that irradiates the same pixel
Study unit .