JPH06281935A - Display device - Google Patents

Abstract

PURPOSE:To perform the uniform and excellent projection with high luminance without remarkably lowering the using efficiency of light even when the aspect ratio of an image is changed and shifting projection is performed. CONSTITUTION:When a light emission element 10 is driven based on an input source by a light emission element driving circuit 12, an output beam is made incident on a space light modulation element 20 through an image formation optical system 14, a polarizing mirror 16 and a zoom optical system 18, and the image is written. A reading beam outputted from a light source 22 and made incident on the space light modulation element 20 from a polarizing beam splitter 24 is modulated corresponding to the written image to be reflected, and is made incident on a screen 28 through the polarizing beam splitter 24 and a projection optical system 26 to be displayed. At this time, the position adjustment by position adjustment mechanisms 30, 32 are performed, and the irradiation with the reading beam corresponding to the aspect ratio of a projection object is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device using, for example, a spatial light modulator for image recording, and more specifically to improvement of its illumination system.

[0002]

2. Description of the Related Art A conventional display device using liquid crystal is shown in FIG. The one shown in FIG. 3A is disclosed in Japanese Patent Application Laid-Open No. 2-275933, and the illumination light of the circular luminous flux output from the light source 100 when passing through the first linear Fresnel lens 102 The light is condensed in the vertical direction indicated by the arrow FA. Then, the light enters the second linear Fresnel lens 104, is collimated there, and then enters the display device 106. Due to the action of the two Fresnel lenses 102 and 104, the circular light flux output from the light source 100 becomes an elliptical light flux and is applied to the display device 106.

Next, what is shown in FIG.
The light source 1 disclosed in JP-A-309389.
The light output from 10 is condensed again by the action of the reflector and then diverges. And the cylindrical lens 11
When it is incident on 4, the divergence is suppressed in the direction of arrow FB, and collimated light is generated in that direction. When it further enters the cylindrical lens 116, its divergence is suppressed in the direction of arrow FC, and collimated light is generated in that direction. By the unidirectional lens action of the cylindrical lenses 114 and 116, the display device 11
The light beam applied to 8 becomes an ellipse.

[0004]

However, the above conventional techniques have the following disadvantages. (1) Each of the above-described lighting devices is a fixed lighting device corresponding to a display device, and the lighting system is fixed according to the maximum possible display screen. So, for example,
It is good when the projection target is predetermined such as for high-vision, but when the aspect ratio changes and the display screen used becomes smaller, the light utilization rate of the light source deteriorates.

(2) Also, 1992 Japanese Patent Application No. 13598
As in the case of application for No. 9, in the case of projecting an image toward a screen located above,
Image projection is performed using a portion of the brightest illumination luminous flux that is off the center, and the image quality deteriorates. The present invention focuses on these points, and even if the aspect ratio of the projection target is changed or tilted projection is performed, a uniform and excellent high-luminance projection is achieved without causing a large decrease in the light utilization rate. It is an object of the present invention to provide a display device capable of performing.

[0006]

In order to achieve the above-mentioned object, a first aspect of the present invention relates to an image recording means for writing an image and an image writing means for writing at least two kinds of images having different aspect ratios. Means, an image reading means for reading and displaying an image written in the image recording means by the means, a light source means for supplying reading light to the image reading means, the light source including a light emitter and a reflector. The light source side adjusting means for changing the relative positional relationship between the light emitter and the reflector of the light source means in accordance with the aspect ratio of the image, and the relative positional relationship between the light source means and the image recording means, the aspect ratio of the image. And an image recording side adjusting means for changing the ratio according to the ratio.

According to a second aspect of the present invention, an image recording means for writing an image and at least two different aspect ratios are provided.
An image writing unit for writing an image of a kind, an image reading unit for reading and displaying the image written in the image recording unit by the image writing unit, a light emitter by an arc and a reflector, Light source means for supplying the reading light, arc adjusting means for changing the position of the arc of the light emitting body of the light source means by a magnetic field corresponding to the aspect ratio of the image, and the relative relation between the light source means and the image recording means. Image recording side adjusting means for changing the physical positional relationship in accordance with the aspect ratio of the image.

According to a third aspect of the present invention, an image recording unit for writing an image, an image writing unit for writing an image on the image recording unit, and an image for reading and displaying the image written on the image recording unit by the image recording unit. The reading means, the light source including the light emitter and the reflector, for supplying the reading light to the image reading means, and the relative positional relationship between the light emitter and the reflector of the light source means are determined by the image reading means. It is characterized in that a light source side adjusting means for changing the image display position is provided.

According to a fourth aspect of the present invention, an image recording unit for writing an image, an image writing unit for writing an image on the image recording unit, and an image for reading and displaying the image written by the image recording unit by the image recording unit. A display means, a light source means for supplying read light to the image reading means including a light emitter and a reflector by an arc, and the position of the arc of the light emitter of the light source means are displayed by the image reading means. It is characterized in that it is provided with an arc adjusting means for changing it by a magnetic field corresponding to the position.

According to the main aspect of the present invention, a spatial light modulator in which a photoconductor and a light modulator are laminated is used as the image recording means. Further, as the image writing means, one provided with a linear light emitting element and a mirror scanning means for scanning the linear light emission by the linear light emitting element and projecting it on the image recording means is used. The image writing means and the image reading means may include optical means having a zoom function and an autofocus function.

[0011]

In the first aspect of the invention, the direction of light reflection by the reflecting means is changed by relatively changing the positions of the light emitter and the reflector, and the shape of the output light beam is adjusted. If the position of the image recording means is adjusted correspondingly, light irradiation corresponding to the aspect ratio of the projection target can be performed. In the second aspect of the invention, the shape of the output light flux is adjusted by changing the position of the arc of the light-emitting body using the magnetic field. If the position of the image recording means is adjusted correspondingly, light irradiation corresponding to the aspect ratio of the projection target can be performed. In the third aspect of the invention, the light reflection direction of the reflection means is biased by relatively changing the positions of the light emitter and the reflector. By utilizing this, it is possible to perform projection with good brightness. In the fourth invention, the position of the arc of the light emitter is changed by using the magnetic field, so that the light reflection direction is biased. By utilizing this, it is possible to perform projection with good brightness.

[0012]

Embodiments of the display device according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows the overall configuration of this embodiment. In the figure, a light emitting element drive circuit 12 is connected to the input side of the light emitting element array 10, and time series image signals of various sources are input to the light emitting element drive circuit 12. An imaging optical system 14, a deflection mirror 16, and a zoom optical system 18 are arranged on the optical path of the output light of the light emitting element array 10. By these, the output light of the light emitting element array 10 is deflected and scanned and is incident on the spatial light modulation element 20.

Next, the spatial light modulator 20 includes a light source 22.
The readout light output from the input device is input via the polarization beam splitter 24. A projection optical system 26 and a screen 28 are arranged on the output optical path of the polarization beam splitter 24. Further, in this embodiment, the spatial light modulator 20 and the light source 22 are provided with a position adjusting mechanism
0 and 32 are provided respectively.

Among the above-mentioned parts, as the light emitting element array 10, for example, an array of light emitting elements such as LEDs, EL, LDs arranged in high density on a straight line is used. The zoom optical system 18 is for changing the image forming magnification of the image with respect to the spatial light modulator 20.

Next, the spatial light modulator 20 is, for example, as shown in FIG.
The configuration is as shown in. In the figure, in each of the transparent glass substrates 20A and 20B, antireflection films 20C and 20D are formed on the light incident side from the outside, and transparent electrodes 20E and 20F are formed on the opposite sides. . A photoconductor 20G, a dielectric mirror layer 20H, and a light modulator 20I are laminated and formed between the pair of transparent electrodes 20E and 20F. Transparent electrode 20
A power supply 20J for driving is connected between E and 20F.

Among the above parts, the transparent electrodes 20E, 20
As F, ITO (Indium Tin Oxide), SnO ₂ or the like is used. Further, as the photoconductor 20G, a-
Si: H (hydrogenated amorphous silicon) or a-Si
C: H (amorphous silicon carbide), CdS,
ZnSe, BSO, etc. are used. The dielectric mirror layer 20H is formed of a laminated body in which Si and SiO ₂ are alternately laminated in an appropriate number, or TiO ₂ and SiO ₂ are alternately laminated in an appropriate number.

Next, as the light modulator 20I, a nematic liquid crystal is used, which has a TN mode and a hybrid electric field effect (HF).
E) mode, guest host (GH) mode, electric field induced birefringence mode (horizontal alignment, vertical alignment), dynamic scattering mode,
It is composed of a liquid crystal valve that operates in any of various modes such as a phase transition mode. Besides, smectic liquid crystal, ferroelectric liquid crystal, polymer liquid crystal composite film, or the like may be used. The antireflection films 20C and 20D are provided as necessary and may be omitted.

Next, the basic operation of the spatial light modulator 20 as described above will be explained.
Photoconductor 20G, dielectric mirror layer 20H, light modulator 20
It is distributed to each layer according to the impedance of I. In such a state, when the writing light including the image information enters as shown by the arrow F1 and reaches the photoconductor 20G, the writing light is absorbed and the impedance of the photoconductor 20G decreases. Then, the dielectric mirror layer 20H and the optical modulator 20I
The driving voltage distributed to the optical modulator 20I is increased, and an electric field corresponding to the intensity distribution of the writing light is formed in the optical modulator 20I.

Here, when the reading light enters as shown by the arrow FB and reaches the optical modulator 20I, it undergoes modulation corresponding to the intensity of the writing light, and is further reflected by the dielectric mirror layer 20H and reflected by the arrow F3. Is output. By such light-to-light conversion, the intensity of the read light can be increased even if the light incident on the photoconductor 20G is weak.

As the writing light, one having a wavelength such that the photoconductor 20G has an impedance change response (that is, sensitivity) is used. Also, as the reading light,
Light of any wavelength may be used as long as it is modulated by the light modulator 20I.

Next, returning to FIG. 1, the position adjusting mechanism 30 is for adjusting the position by moving the spatial light modulator 20 in the direction of arrow F4. The position adjusting mechanism 32 is for adjusting the position by moving the reflector 22A of the light source 22 in the directions of arrows F5A and F5B. Further, the zoom optical system 18 and the projection optical system 26 are provided with an auto-focus mechanism so that an image can be projected with good focus.

Next, the overall operation of the embodiment configured as described above will be described. The light emitting element drive circuit 12 drives the light emitting element array 10 based on various input sources. The output light of the light emitting element array 10 is incident on the deflection mirror 16 via the imaging optical system 14 as shown by an arrow F6. The light deflected and reflected here enters the spatial light modulator 20 through the zoom optical system 18. This operation is sequentially performed in response to scanning by the rotation of the deflection mirror 16 in the direction of the arrow F10, and an image is written in the spatial light modulation element 20 with a predetermined aspect ratio.

The reading of the image written in the spatial light modulator 20 is performed as follows. The readout light output from the light source 22 enters the polarization beam splitter 24 as indicated by an arrow F7, and the readout light whose optical path has been changed enters the spatial light modulation element 20. The read light is subjected to light modulation corresponding to the image written in the spatial light modulator 20, is reflected, and is again polarized beam splitter 2
It is incident on 4. This polarization beam splitter 24 is
The modulated light that has been transmitted as shown by 8 is further reflected by the projection optical system 26.
Is transmitted and is incident on the screen 28 as indicated by an arrow F9. As a result, the image is projected and displayed on the screen 28.

By the way, recently, as an input source,
In addition to the so-called NTSC television, there are televisions with different aspect ratios such as high-definition television. For example, the aspect ratio of the NTSC system is 4: 3, while the aspect ratio of the cinemascope is 2.
The aspect ratio for 2: 1 and HDTV is 16: 9.
Is. In the present embodiment, the zoom optical system 18 changes the magnification of image writing to the spatial light modulator 20 according to the source in order to cope with such a variation in the aspect ratio of the input source.

Further, in the present embodiment, the position adjustment mechanisms 30 and 32 adjust the illumination according to the aspect ratio. FIG. 3 shows the state of the output light beam from the light source 22. Further, the light source portion is enlarged and shown in FIG. It is assumed that the optical axis of the reflector 22A of the light source 22 and the optical axis of the lamp 22B coincide with each other.
It is assumed that a parabolic mirror is used as A.

If the lamp 22B is assumed to be a point light source and is arranged at the focal point of the reflector 22A, parallel light is obtained as shown by the dotted line in the figure. However, in reality, the lamp 22B has a predetermined size, and the light output with a deviation from the focus position does not become parallel light as shown by the solid line or the dashed line. By using such a relationship, it is possible to efficiently change the irradiation range of the illumination light flux irradiated onto the spatial light modulation element 20 by changing the positions of the lamp and the reflector. In this embodiment, the light flux is changed by the adjustment in the direction of the arrow F5A by the position adjusting mechanism 32.

The optical distance between the reflector 22A and the spatial light modulator 20 is not affected by parallel light, but is optimized so that unevenness in intensity does not occur due to deviation from parallel light. There is a need. In this embodiment,
The position adjustment mechanism 30 adjusts such unevenness in strength.

For example, as shown in FIG. 5, it is assumed that an image P1 having an aspect ratio of 1: 1 is written on the spatial light modulator 20, and the position adjusting mechanisms 30 and 32 are adjusted to an optimum state and shown by a circle C1. It is assumed that the reading light having a luminous flux shape is obtained. The light utilization rate η _{1 in} this case is η ₁ = area of image P1 / area of circle C1 = L ² / (π · (L / √2) ² ) = 63. It will be 7%.

Next, in this illumination state, the image P2 corresponding to the aspect ratio of the written image is 16: 9 in HDTV.
Then, the light utilization rate η ₂ is L, M on the sides of the image P2.
(However, if L: M = 16: 9 and M = 9L / 16), then η ₂ = area of image P2 / area of circle C1 = (L × M) / (π · (L / √ 2) ² ) = 35.8%, which is a significant decrease.

However, in this embodiment, the position adjusting mechanism 3
0, 32 to change the read light beam shape from circle C1 to circle C
It can be 2. Then, the light utilization rate η ₃ is η ₃ = area of image P 2 / area of circle C 2 = (L ×, where R is the radius of circle C 2 (where R = √ (L ² + M ² )) M) / (π · R ² ) = 54.4%, which is a significant improvement.

Next, referring to FIGS. 1 and 6, the case of performing tilted projection will be described. In this case, the image is projected onto the screen located above arrow F11 in FIG. 1 (or below arrow F12, or in the left-right direction orthogonal thereto). In the present embodiment, as shown by the arrow F5B in FIG.
The optical axis of the lamp 22B is shifted from the optical axis of 2A.

For example, as shown in FIG. 6, the reflector 2
The position adjusting mechanism 32 sets the optical axis X2 of the lamp 22B at a position Δ away from the optical axis X1 of 2A. Then, the light from the lamp 22B is output as shown in the figure, and intensity unevenness that is not concentric is generated. Therefore, if the position adjustment mechanism 32 performs the optimum adjustment, the spatial light modulator 20
You can set the lighting so that the center of the used area becomes brighter,
You can get natural images.

Thus, according to this embodiment, the light source 22
By providing the position adjusting mechanisms 30 and 32 for adjusting the positions of the lamp 22B and the reflector 22A, and the positions of the reflector 22A and the spatial light modulation element 20, respectively, the aspect ratio of the projection target is changed or the tilted projection is performed. Even in such a case, it is possible to prevent a significant decrease in the light utilization rate and perform uniform and favorable high-luminance image projection. Also,
Since the image is written in the spatial light modulation element 20 by using the line-shaped light emitting element array 10, the resolution is also good.

Next, another embodiment will be described with reference to FIG. In this embodiment, the light source means (light source 22) and the light source side adjusting means (position adjusting mechanism 3) in the above embodiment are used.
It is a modification of the part 2) and utilizes the arc lamp disclosed in the specification of US Pat. No. 5,057,747.

In the figure, the arc lamp 5 of the light source 50 is shown.
A power source (indicated by PS) 52 is connected to the first discharge electrode. Further, the reflector 54 of the light source 50 is provided with a plurality of, for example, four electromagnetic coils 56. In the figure,
Two of them are shown. An adjustment current is supplied to the electromagnetic coil 56 from an adjustment power supply (indicated by RPS) 58. Further, the polarization beam splitter 24 shown in FIG. 1 is arranged in the light output direction of the light source 50 shown by the arrow F7. The other parts are the same as in the above embodiment.

Next, the operation of this embodiment will be described. Electric power is supplied from the power supply 52 to perform arc discharge between the electrodes of the arc lamp 51. In this state, when a current is passed from the adjusting power source 58 to the electromagnetic coil 56, a magnetic field is generated. Then,
This magnetic field affects the arc, and the position of the arc moves slightly. The magnitude of the magnetic field can be changed according to the magnitude of the current. Therefore, the degree of the magnetic field can be adjusted by adjusting the amount of electricity supplied to the electromagnetic coil 56 by the adjusting power source 58, and the position of the arc can be finely adjusted.

According to the method of changing the position of the arc by this magnetic field, the electric method shown in FIG. 3 (and FIG. 4) or FIG. 6 is used instead of the mechanical method such as the position adjusting mechanism. It becomes possible to perform adjustment work.

The present invention is not limited to the above embodiment, and includes, for example, the following. In the above-described embodiment, both the reflector 22A of the light source 22 and the spatial light modulator 20 are moved. However, since it is only necessary that the optical distance between the two is changed, only one of them is configured to be movable. Good. As for the lamp 22B and the reflector 22A of the light source 22, it is sufficient that the positional relationship between the lamp 22B and the reflector 22A relatively changes, and thus both may be movable.
Only one of them may be movable.

It is also possible to provide a brightness adjusting means for the light source so that the display brightness is adjusted according to the display mode such as the aspect ratio and the tilted projection. Furthermore, the aspect ratio of the projection target is often limited to several types such as the normal NTSC system and high definition. Therefore, in each of these cases, optimum reflector position conditions and appropriate light source brightness may be obtained in advance, and position setting and brightness setting may be automatically performed using a microcomputer or the like.

In the above-mentioned embodiment, the present invention is applied to the irradiation of the illumination light when reading the image written in the display device by using the polarization beam splitter.
INDUSTRIAL APPLICABILITY The present invention is applicable to general light irradiation to display devices. In addition, the display device is R (red), G (green), B
The present invention can be applied to a display device for color projection provided for each (blue). In this case, R, G, B
The apparatus shown in FIG. 1 may be provided for each unit, and the R, G, and B read images may be combined and projected on the screen.

[0041]

As described above, the display device of the present invention has the following effects. (1) Since the relative positional relationship between the light emitter and the reflector and the relative positional relationship between the reflector and the image recording unit are changed in accordance with the aspect ratio of the image, the aspect ratio of the projection target is changed. Even if it changes, a uniform and high-luminance image can be displayed without causing a large decrease in the light utilization rate. (2) Since the position of the arc of the light emitter is changed by using the magnetic field, the light source side is electrically adjusted without using a mechanical mechanism to change the aspect ratio of the projection target. Also, a uniform and high-luminance image can be displayed without causing a large decrease in the light utilization rate.

(3) Since the relative positional relationship between the light emitter and the reflector is changed in accordance with the display position of the image, the tilt projection can be favorably performed. (4) Since the position of the arc of the light emitting body is changed by using the magnetic field, it is possible to electrically adjust the light source side without using a mechanical mechanism and perform favorable tilt projection. .

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram showing an example of a spatial light modulator.

FIG. 3 is an explanatory diagram showing a relative relationship between a lamp and a reflector and a state of light output.

FIG. 4 is an explanatory view showing a lamp portion of FIG. 3 in an enlarged manner.

FIG. 5 is an explanatory diagram showing a relationship between an image aspect ratio and a luminous flux in the embodiment.

FIG. 6 is an explanatory diagram showing a state of a light source when performing tilted projection.

FIG. 7 is an explanatory diagram showing a main part of another embodiment.

FIG. 8 is a perspective view of a main part showing a conventional technique.

[Explanation of symbols]

 10 ... Light emitting element array (image writing means) 12 ... Light emitting element drive circuit (image writing means) 14 ... Imaging optical system (image writing means) 16 ... Deflection mirror (image writing means) 18 ... Zoom optical system (Image writing means) 20 ... Spatial light modulation element (image recording means) 22, 50 ... Light source (light source means) 22A, 54 ... Reflector (reflector) 22B ... Lamp (light emitter) 24 ... Polarized beam splitter (image reading) Means) 26 ... Projection optical system (image reading means) 28 ... Screen 30 ... Position adjusting mechanism (image recording side adjusting means) 32 ... Position adjusting mechanism (light source side adjusting means) 51 ... Arc lamp 52 ... Power source (PS) 56 ... Electromagnetic coil (arc adjusting means) 58 ... Power source for adjustment (RPS, arc adjusting means) C1, C2 ... Circles showing light flux shape L, M ... Side lengths P1, P2 ... Image R ... Radius of circle C2 X1 , X2 ... Optical axis

Claims (4)

[Claims] 1. An image recording means for writing an image,
An image writing unit for writing at least two types of images having different aspect ratios, an image reading unit for reading and displaying the image written in the image recording unit by the image writing unit, and a light emitter and a reflector are included. Light source means for supplying the reading light to the image reading means, and light source side adjusting means for changing the relative positional relationship between the light emitter and the reflector of the light source means in accordance with the aspect ratio of the image. A display device, comprising: an image recording side adjusting means for changing a relative positional relationship between the light source means and the image recording means in accordance with an aspect ratio of an image. 2. Image recording means for writing an image,
Image writing means for writing at least two types of images having different aspect ratios to this, image reading means for reading and displaying the image written in the image recording means by this, luminous body and reflector by arc A light source means for supplying read light to the image reading means,
The arc position adjusting means for changing the position of the arc of the light emitter of the light source means by the magnetic field corresponding to the aspect ratio of the image, and the relative positional relationship between the light source means and the image recording means correspond to the aspect ratio of the image. And a change means for adjusting the image recording side for changing the display apparatus. 3. An image recording means for writing an image,
Image writing means for writing an image thereon, image reading means for reading and displaying the image written by the image recording means by the image writing means, a light emitter and a reflector, and the reading light for the image reading means. A light source means for supplying
The relative positional relationship between the light emitter and the reflector of this light source means
A display device comprising a light source side adjusting means for changing the image display position by the image reading means according to the display position. 4. An image recording means for writing an image,
Image writing means for writing an image thereon, image reading means for reading out and displaying the image written in the image recording means by the image writing means, and a light emitter and a reflector by an arc are included in the image reading means. The light source means for supplying the reading light and the position of the arc of the light emitter of the light source means
A display device comprising arc adjusting means for changing the image by the magnetic field corresponding to the display position of the image by the image reading means.