JP2001042237A - Video display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a video display device where incoherent light is set as a light emitting source such as an LED and which obtains a high-luminance and high-resolution projected video by compact structure. SOLUTION: This device is equipped with an LED array 3 emitting light in response to an inputted video signal, and a polygon mirror 7 receiving the light condensed by narrowing the beam diameter of the light from the array 3 and deflecting it. The deflecting direction of a scanning line in a horizontal direction is displaced to a vertical direction by the reflection surfaces of the mirror 7 having different tilt angles or the deflecting direction of the scanning line in the horizontal direction is displaced to the vertical direction by changing posture at the time of rotating the polygon mirror.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display apparatus for displaying an image signal of an image equipment such as a personal computer or a television with a semiconductor light emitting element such as a light emitting diode and projecting the image on a screen or a wall.

[0002]

2. Description of the Related Art As a device for displaying an image formed by a personal computer on a screen or the like, a liquid crystal projector using a transmission type liquid crystal has been conventionally known. This liquid crystal projector displays images on three transmissive liquid crystal panels for each of red, green, and blue, and separates the white light source into red, green, and blue with a special mirror to produce red, green, and blue. Are projected onto the respective liquid crystal panels, which perform the color synthesis, and the color-combined image is enlarged and projected.
This kind of liquid crystal projector is being commercialized, and it can be said that the spread to the market is quite high at present.

However, the transmissive liquid crystal panel used in the current liquid crystal projector has a light transmittance of about 2
It is about 5%, and the light transmittance is low for use in an optical system. Therefore, there is a limit to the brightness of the display image projected on the screen, and brightness sufficient to withstand use in a bright place has not been realized.

In a liquid crystal projector, a rise in the temperature of a transmission type liquid crystal cell due to heat contained in light from a light source is inevitable. When the temperature of the liquid crystal cell rises in this way, it causes a decrease in contrast and color unevenness,
A color shift at the time of combining three colors of red, green, and blue also occurs, and the projection performance is significantly deteriorated. At the same time, the need for three liquid crystal panels and the complexity of the optical system, such as a separation mirror for red, green, and blue emission of white light from a white light source, require a large number of parts and assembly steps, resulting in cost reduction. Surface problems cannot be ignored.
Further, it is difficult to increase the size of the liquid crystal panel in accordance with the resolution in order to increase the resolution of a display image. Therefore, the only way to achieve high resolution of the display image projected on the screen is to increase the area ratio of the cell separation portion of the liquid crystal panel, so that the light transmittance is further reduced. Therefore, even if a high-resolution display image is obtained, the luminance is low, and it is difficult to optimize the display image in both resolution and luminance.

An image display device using a light emitting diode (hereinafter, referred to as "LED") made of a compound semiconductor has been already proposed in place of the liquid crystal projector having the above disadvantages. For example, Japanese Patent Application Laid-Open No. Hei 9-230499 has been proposed. There is a description in the gazette. The projector described in this publication includes a light emitting diode unit including at least one or more red, green, and blue LEDs for displaying an input video signal as an image, and an image light displayed by the light emitting diode unit. It has a Fresnel lens for condensing light and is configured to be detachably disposed in an optical path toward a screen of an overhead projector.

[0006]

However, in the projector using the LED described in the above publication, the number of pixels of the light emitting diode unit becomes the number of pixels of the display image after being projected and enlarged on the screen. Therefore, the image of the light emitting diode unit has a low resolution, and the resolution of the enlarged display image on the screen is inevitably low, so that it is not possible to cope with the currently required high resolution image display.
For example, if the horizontal resolution is 800 dots and the vertical resolution is 60
If a color image of 0 dots is to be displayed according to its resolution, at least 800 × 600 × 3 = 1,4
A huge number of LEDs of 40,000 is required.
Therefore, the apparatus cannot be made compact, and since a large number of LEDs are used, the power consumption is increased and the cost is greatly impeded.

[0007] As described above, in the conventional projector using LEDs, unless a very large number of LEDs are provided, high resolution of a display image on a screen cannot be achieved.
There are problems in practical use and commercialization.

[0008] Proposals have already been made for an image display device using a laser that is coherent light. However, although a laser can display an image itself, it has a wavelength of 40 nm as a violet semiconductor laser in the blue region.
At present, samples with an output of about 5 mW at 0 nm are shipped. Therefore, a high-luminance full-color image as in the case of using R, G, and B light-emitting diodes cannot be realized, and is not optimal at present for displaying various images.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an image display device which uses an incoherent light source such as an LED as a light source and obtains a high-brightness, high-resolution projected image with an extremely compact structure.

[0010]

According to the present invention, there is provided an image display apparatus comprising: a plurality of light sources of incoherent light emitted in response to an input image signal; and a beam diameter of light emitted from the light source. Focusing means for arranging the light beam and arranging the light beam in a uniaxial direction, deflecting means for receiving light from the condensing means and deflecting the light beam in two axial directions, and displaying the light from the deflecting means with distortion correction. And a distortion correcting means for forming an optical path toward the surface.

In the present invention, the deflecting means may be a polygon mirror having a plurality of reflecting surfaces formed on a peripheral surface and rotating around an axis, and the plurality of reflecting surfaces may be adjacent to each other in a circumferential direction. It is possible to adopt a configuration having a certain angle difference so that the deflection direction of the horizontal scanning line is displaced in the vertical direction.

Further, the plurality of reflecting surfaces of the polygon mirror are
The posture of the polygon mirror may be changed at the same time as the rotation about the axis so that the deflection direction of the horizontal scanning line between the circumferentially adjacent scanning lines is vertically displaced.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

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

Referring to FIG. 1, an image display apparatus 1 for projecting light onto a large screen 50 to display an image includes an analog red (R), green (G), and blue (B) of an image device (not shown). ), A signal conversion unit 2a, an LED control unit 2b, a polygon mirror control unit 2c, and a screen 50.
And an optical system for forming an image of a projected image on the optical disk. The signal conversion unit 2a performs A / D conversion and synchronization of the video signal input from the video device, inputs the output signal to the LED control unit 2b, and outputs the output signal to the LED control unit 2b.
b performs gamma correction and gradation control to execute R and R of the optical system.
The LED corresponding to the pixel among the G and B LEDs is turned on. The polygon mirror controller 2c controls the rotation of a polygon mirror (described later) included in the optical system.

The optical system includes an LED array 3, a condenser lens 4, an optical fiber 5, a light emitting array 6, a polygon mirror 7,
A distortion correction lens 8 and a projection lens 9 are provided, each having a horizontal resolution of 800 pixels and a vertical resolution of 600 pixels.
The moving image can be displayed by rewriting 60 times per second. Note that the vertical resolution direction (Y-axis direction) is the vertical direction of the screen 50 with respect to the screen 50 in FIG.
The horizontal resolution direction (X-axis direction) is a direction orthogonal to the drawing.

As shown in FIG. 2, the LED array 3 has a total of 200 light-emitting sources 3-1, 3-2... 3-199, 3-200 arranged in a row in the Y-axis direction. Each of the light emitting sources 3-n (n = 1 to 200) is R, G, B
LEDs 3a, 3b, 3c. Note that R,
In addition to the G and B LEDs 3a, 3b and 3c, LEDs of other luminescent colors may be incorporated. If the display device is compatible with a mono-color screen, it has at least one luminescent color of R, G and B. I just need.

In this embodiment, the light collecting means is constituted by a combination of the light collecting lens 4, the optical fiber 5, and the light emitting array 6. The condenser lens 4 is arranged coaxially with the optical axis of each light emitting source 3-n of the LED array 3, and an optical fiber 5 is arranged in connection with each of these condenser lenses 4. The condenser lens 4 narrows the beam diameter of light from each of the light emitting sources 3-n of the LED array 3. The optical fiber 5 is for forming a light guide path to the light emitting array 6, and makes the irradiation light incident on the light emitting array 6 with an optimized beam diameter. The light-emitting array 6 has a condenser lens 6a-1, 6a-2,... Which makes light from all the light-emitting sources 3-1 to 3-200 incident on the surface of the polygon mirror 7 in a parallel relationship with high precision. -It has 6a-200. Since the optical fiber 5 has a small outer diameter and can be freely bent as is well known in the related art, even if the optical path from the condenser lens 4 to the light emitting array 6 is complicatedly bent, it can be easily assembled.

The polygon mirror 7 is widely used, for example, in the field of an optical writing device such as a printer, and has a substantially hexagonal prism shape as shown in FIG. 1, and is driven around the center of the hexagon as a rotation center. It is rotationally driven by a motor (not shown).

3A and 3B show details of the shape of the polygon mirror 7. FIG. 3A is a plan view seen from above, and FIGS.
(D) is AA, BB, CC of FIG.
It is a longitudinal cross-sectional view by a line arrow. As shown in the figure, the upper end surface of the polygon mirror 7 is a regular hexagon, and its peripheral surface is connected to six reflecting surfaces 7a, 7b, 7c, 7d, 7e, 7f. The reflecting surface 7a is a surface parallel to the central axis of the polygon mirror 7, and the reflecting surfaces 7b and 7c connected to the reflecting surface 7a are slightly inclined to narrow the cross section on the lower end side as shown in FIGS. However, the inclination angle of the reflection surface 7c is almost twice as large as that of the reflection surface 7b. The reflecting surface 7d connected to the inclined surface 7c,
7e and 7f are the same as the relationship between the reflection surfaces 7a, 7b and 7c described above. In other words, the peripheral surface of the polygon mirror 7 is formed of three consecutive surfaces of the reflection surfaces 7a, 7b, 7c and the reflection surfaces 7d, 7d.
e, 7f, which is a combination of three surfaces, and when the polygon mirror 7 is driven to rotate, light from one arbitrary light emitting source 3-n is reflected by the three reflecting surfaces 7a, 7b, 7c or reflected. Face 7
When scanning is performed by d, 7e, and 7f, any one light emitting source 3-n generates three rows of horizontal picture pixels during half rotation of the polygon mirror 7 (see FIG. 4 described later). That is, 2
The 00 light-emitting sources generate image pixels of 600 lines in the horizontal direction during the half rotation of the polygon mirror 7, and 800 × 60
Zero pixels can be generated.

The distortion correction lens 8 takes in the light deflected in the horizontal and vertical directions by the polygon mirror 7 and makes it incident on a projection lens 9. This projection lens 9 enlarges and projects the incident light onto a screen 50 to form an image. indicate.

Here, when a video signal is input to the signal converter 2a, the LED controller 2b controls the LED array 3 based on the video signal, and the R, G, and B LEDs 3a,
3b and 3c blink. As a result, the light emitting sources 3-1 to 3-200 arranged in a line in the Y-axis direction blink, and the irradiation light is applied to the condenser lens 4 arranged in correspondence with each of the light emitting sources 3-1 to 3-200. Incident. The irradiation light is guided from the condenser lens 4 through the optical fiber 5 toward the light emitting array 6.

As described above, the LED array 3 and the light emitting array 6
By providing the condenser lens 4 and the optical fiber 5 corresponding to each of the light emitting sources 3-1 to 3-200,
The arrangement of the light emitting sources 3-1 to 3-200 of the LED array 3 can be arbitrarily set. That is, since the optical fiber 5 whose length and bending can be freely set forms a light guide path to the light emitting array 6, the degree of freedom of the positional relationship of the light emitting sources 3-1 to 3-200 with respect to the light emitting array 6 can be set high. Therefore,
In FIG. 2, the light-emitting sources 3-1 to 3-200 are the simplest examples.
Are arranged in a line in the Y-axis direction, but are not limited to such an arrangement. For example, as shown in FIG.
The LED array 3 is formed into a substantially square shape, and the light emitting source 3-
1 to 3 to 200 are arranged at a uniform density, and the LED shown in FIG.
Compared with the array 3, the height can be reduced and the size can be reduced. Also, as shown in FIG. 5B, for example, three light-emitting arrays 31, 32, and 33 are arranged at appropriate positions in the video display device 1, and a predetermined number of light-emitting 1-3 to 200 may be distributed. In short, the light emitting array 6 for irradiating the polygon mirror 7 with light
Is assembled with high precision, the arrangement position and the number of the LED arrays 3 can be set arbitrarily. In particular, by appropriately using the space in the video display device 1 as in the example of FIG. Compactness is achieved.

Returning to FIG. 1, the condenser lenses 6a-n (n = 1 to 200) of the light emitting array 6 correspond to the respective optical paths from the light emitting sources 3-1 to 3-200 of the LED array 3. In this example, 200 pieces are arranged in the Y-axis direction. Light from these condenser lenses 6a-n is applied to one of the reflection surfaces 7a to 7f of the polygon mirror 7 while being focused at equal intervals in the Y-axis direction. Then, the light emitting sources 3-1 to 3-
By the blinking operation by the image signal of 200, the rotation of the polygon mirror 7, and the deflection based on the inclination of each of the reflection surfaces 7a to 7f,
Scanning is performed in the horizontal (X-axis) direction and the vertical (Y-axis) direction to form an image on the screen 50. It goes without saying that the blinking operation of each of the light emitting sources 3-1 to 3-200 and the synchronization of the polygon mirror 7 are synchronized with the video signal.

FIG. 6 shows a horizontal (X-axis direction) resolution 800 pixels and a vertical (Y-axis direction) resolution 6 with respect to the screen 50.
It is the schematic which shows the line display of the image by 00 pixels.

On the screen 50, there are 600 lines L
-1, L-2, L-3, ... L-599, L-600
Is displayed. Then, the light emitting source 3-1 of the LED array 3
Performs the image display of the lines L-1 to L-3, the light emitting source 3-2 in the next stage performs the image display of the lines L-4 to L-6, and similarly, the light emitting source 3-200 performs the line L -598 to L
Each of the light emitting sources 3-n contributes to the display of three lines of images by scanning while the polygon mirror 7 rotates half a turn. That is, when light from the light emitting array 6 is incident in a direction perpendicular to the reflection surface 7a, the distortion correction lens 8 is directed from the reflection surface 7a in a direction perpendicular to the axis of the polygon mirror 7 as shown by a solid line in FIG. The light is emitted to FIG case, the reflecting surface 7b, the light incident on 7c by the respective slopes of the angular difference of the slope of the reflecting surface 7a reflection surface 7b and theta ₁ to the reflecting surface 7a and the angular difference theta ₂ of inclination of the reflection surface 7c 4, the angle of θ ₁ with respect to the reflected light from the reflecting surface 7a, that is, the two-dot chain line and the reflecting surface 7a
That angle of theta ₂ with respect to the reflected light from being emitted in the direction of the arrow shown by a chain line.

Here, the reflecting surface 7b,
The angles θ ₁ and θ ₂ of the light-emitting array 6, for example, the light from the condenser lens 6 a-1 is reflected by the reflection surface 7 a of the polygon mirror 7.
Are set so that the distances p1 and p2 between the scanning lines to the distortion correction lens 8 when reflected by the lens are equal. Also, the condenser lenses 6a-1, 6a-
2 spacing intervals P ₁ shown in FIG. 4, P _2, P ₃ is P ₁ = P ₂ =
It is set so that the relationship of P ₃ is established. Thereby, the operation line of the light reflected sequentially by the reflecting surfaces 7a~7f of emitted polygon mirror 7 from the condenser lens 6a-1, 6a-2 of the light-emitting array 6, P ₁ to P ₅ in FIG. 4 Can be set to correspond to equal lines.

As described above, the reflection surface 7 of the polygon mirror 7 is
Each of the condenser lenses 6-n of the light emitting array 6 as shown in FIG. 4 by scanning while the polygon mirror 7 makes a half rotation by giving an angle difference between each of the light-receiving elements 6a to 7c and 7d to 7f. Can be incident on the distortion correction lens 8 as scanning light via the optical paths of the solid line, the two-dot chain line, and the one-dot chain line. Therefore, an image can be displayed by projecting three lines on the screen 50 during the half rotation of the polygon mirror 7.

Here, since the number of pixels in the horizontal resolution (X-axis direction) of each of the lines L-1 to L-600 is 800, in order to be able to display as a flicker-free moving image, for example, one line is required. Horizontal scanning may be performed about 60 times per second. For such a horizontal scanning condition, the R, G, and B LEDs 3 are used only for about 60 times 800 pixels.
What is necessary is just to change the blinking conditions of a, 3b, and 3c. When displaying the vertical resolution of 600 pixels by the 200 light-emitting sources 3-1 to 3-200, one arbitrary light-emitting source 3-n has a high-speed response of 800 × 60 × 3 = 144000, that is, 144 KHz or more. If there is. Note that, in the present embodiment, a numerical value ignoring the blanking period of the video is specified for the sake of easy understanding,
This is because there is no problem in the response characteristics and the rotation speed of the polygon mirror even if the retrace period is taken into consideration.

On the other hand, the LEDs 3a, 3b, and 3c which have been developed so far have a high-speed response of 7 MHz or more, so that the number of pixels of the horizontal resolution is 800 and the vertical direction can correspond to three lines.

As described above, the LED 3a having a high-speed response,
In the light sources 3-1 to 3-200 including 3b and 3c, blinking control of all the LEDs 3a, 3b and 3c is possible so as to rewrite 800 × 600 pixels 60 times per second in response to a video signal.

That is, if the polygon mirror 7 is rotated and scanned in the X-axis direction once every 1/180 second, the light-emitting sources 3-1 to 3-200 of the light-emitting array 3 first As described above, one pixel is controlled to blink between 1/1444000 seconds, so that light passing through the light-emitting array 6 from 200 light-emitting sources arranged in a line in the Y-axis direction is sequentially transmitted to pixels in the X-axis direction. It is deflected. Then, the light surface deflected from the polygon mirror 7 is incident on the distortion correction lens 8 to correct the distortion, and is projected from the projection lens 9 onto the screen 50. Thus, as shown in FIG. 6, an image having a horizontal (X-axis direction) resolution of 800 pixels and a vertical (Y-axis direction) resolution of 600 pixels is projected 60 times per second on the screen 50 to form a video. You.

As described above, the irradiation light from one light emitting source 3-n is reflected by the reflecting surfaces 7a and 7a of the polygon mirror 7 having different inclinations.
By applying the light to the combination of 7b and 7c and then to the combination of the reflection surfaces 7d, 7e and 7f, an image display of three lines is obtained as shown in FIG. For this reason, while a large number of 800 × 600 light emitting sources and at least 800 × 600 × 3 LEDs were conventionally required for color display, 200 light emitting sources 3-1 to 3-3 were used. −200
R, G, B constituting the light emitting array 6
, The total number (200 × 3) of the LEDs 3a, 3b, 3c can be greatly reduced, and miniaturization of the device and reduction of the manufacturing cost can be achieved. Since the LEDs 3a, 3b, 3c are greatly reduced, the power consumption during operation is also reduced.

In addition, blue and green LEDs using nitride-based compound semiconductors developed recently have been increasing in brightness.
Red LED using AlGaInP-based compound semiconductor
Similarly, high brightness was achieved. Accordingly, if blue and green LEDs made of a nitride-based compound semiconductor and red LEDs made of an AlGaInP-based compound semiconductor are applied to the light sources 3-1 to 3-200, a screen image with high brightness can be obtained. The present inventors have confirmed that the R, G, and B LEDs 3a,
3b, in the case of LED array 3 and the light emitting source 3-1～3-200 were 200 sequences comprise one by one is 3c, the screen 50 size of approximately 500 cd / m ² is on the screen 50 when a 1 m ² A high-luminance image was obtained. Therefore, it is possible to sufficiently display images in a bright room in the daytime, and to provide R, G, and B LEDs 3a, 3b, and 3c in all of the light-emitting sources 3-1 to 3-200, thereby enabling one pixel to be displayed. There is no color shift, and the screen 5 cannot be avoided in principle with a conventional liquid crystal projector.
The occurrence of a color shift of the image on 0 can be completely prevented. If a brighter display device for outdoor use is required, the same configuration can be easily realized by increasing the number of LEDs constituting each light emitting source 3-n.

FIGS. 7A and 7B show details of another example of the polygon mirror. FIG. 7A is a plan view seen from above, and FIGS.
(C) and (d) show the DD line, EE line, and F line in FIG.
It is sectional drawing by the -F line arrow.

The polygon mirror 10 in the illustrated example has a hexagonal prism shape as in the previous example, but the inclination angles of the six reflecting surfaces 10a to 10f are changed stepwise in the circumferential direction. . That is, the reflecting surface 10a is
When the surface is parallel to the rotation axis of 0, the reflection surface 10a
Reflecting surfaces 10b, 10c, 10d, 10e, 10
The inclination angle increases in the order of f. When such a polygon mirror 10 is provided in the optical system shown in FIG. 1 and a light beam is emitted from the light emitting array 6, scanning lines are formed during one rotation of the polygon mirror 10 as shown in FIGS. Can be displaced in the vertical (X-axis) direction with six deflection directions. That is, the light beam caused by the blinking of one light emitting source generates image pixels displaced in the vertical (X-axis) direction of six lines by horizontal deflection by the respective reflecting surfaces 10a to 10f. In addition, as the interval between the distance and the position P ₆ and the next scan line P ₁ of the located if P ₁ to P ₆ adjacent the respective scan lines by the respective reflecting surfaces 10a~10f equals none, each of these Reflective surfaces 10a-10
The relationship between the inclination angle of f and the interval between the light beams emitted from the adjacent condenser lenses 6a-n is the same as in the previous example.

As described above, with one rotation of the polygon mirror 10, the deflection direction of the scanning line in the horizontal direction is changed to six lines in the vertical direction, and the image display with 100 light emitting sources for the vertical resolution of 600 pixels. It is possible to reduce the number to half in comparison with the 200 LED arrays 3 shown in FIG. 3, and to obtain a total of 30 R, G, B LEDs 3a, 3b, 3c.
Only 0 pieces are needed. For this reason, the structure from the light emitting source to the light emitting array section is simplified, and the size is further reduced.
When there is a concern about insufficient luminance, it is only necessary to increase the number of LEDs included in each light emitting source, and it is not necessary to increase the number of light emitting sources.

FIG. 9 is a schematic diagram showing an example of another deflecting means using a polygon mirror.

In FIG. 9, a polygonal mirror 11 having a regular hexagonal prism shape is provided integrally with a support shaft 11a coaxially with its axis, and this support shaft 11a is included in a vertical plane so as to be freely rotatable and its lower end is formed. It is connected to a drive motor (not shown) and can be driven to rotate. The support shaft 11a is conductive,
The permanent magnet 12 is inserted between the N pole and the S pole of the permanent magnet 12 with the upper end side as a free end. The permanent magnet 12 is disposed such that the magnetic field lines from the N pole to the S pole are in the horizontal (X-axis) direction, and the support shaft 11a having a vertical axis included in the vertical plane is located between the N pole and the S pole. Are positioned so as to cut through the magnetic flux of

Here, the polygon mirror 11 is driven to rotate around the support shaft 11a by a drive motor in the same manner as in the previous example. When a current I flows in the direction of the arrow by energizing the support shaft 11a during this rotation, the Lorentz force F is reduced in the drawing by the magnetic flux B between the N pole and the S pole of the permanent magnet 12 and the current I. Acts toward the side. Accordingly, the support shaft 11a tends to move toward the near side by the Lorentz force F, and thus a position sensor (not shown) such as a camera is used.
Is used to detect the position of the support shaft 11a and feed it back to the current I to accurately control the polygon mirror 11. At this time, since the generated Lorentz force F increases as the applied value of the current I increases, the inclination angle of the polygon mirror 11 also increases.

From the above, the application of the current I and the polygon
Synchronize the rotation of the mirror 11 and appropriately control the applied value of the current I.
If so, the six reflecting surfaces 11b to 11 of the polygon mirror 11
The slope of g can be changed as shown in FIG. This inclination
The inclination is set based on the deflection of the support shaft 11a due to the Lorentz force F.
For example, when the reflecting surface 11b is vertical, FIG.
The deflection angle θ of the support shaft 11a at 0₁~ Θ_FiveCorresponding to the remaining
Current I so that the reflection surfaces 11c to 11g are sequentially inclined.
What is necessary is just to change the size of. And these θ ₁~ Θ_Fiveof
The size and the distance between the emitted light are the same as in the previous example.
Interval P of displacement of horizontal scanning line₁~ P₆Next to
Are set so that the size between them is constant. What
When using the polygon mirror 11 shown in FIG.
Since the reflecting surfaces 11b to 11g rotate while tilting,
The lines L-1 to L600 on the clean 50 are shown in FIG.
Although it is slightly tilted as shown in
There is no hindrance at all.

As described above, while the polygon mirror 11 is rotated, each of the reflecting surfaces 11b-1
Six surfaces of 1 g can be sequentially set to different inclination angles. Therefore, if an image of a pixel having a horizontal resolution of 800 and a vertical resolution of 600 is displayed 60 times per second to project a video,
It is sufficient to prepare 00 light-emitting sources, and as in the example of FIG.
The number of EDs can be significantly reduced.

In the embodiment, the R, G, and B LEDs are taken as examples of the semiconductor light emitting element. However, an organic electroluminescence element that emits incoherent light may be used.
As the deflecting means, a prism using an electro-optic crystal may be used instead of the polygon mirror, and the deflecting means and the distortion correcting means may be integrated. The screen may be separate from the video display device as in the embodiment, or may be an integrated rear projection type. Further, a system having a larger scale and higher resolution may be configured by combining some of the video display devices of the present invention. Needless to say, it is possible to display not only moving images but also images such as characters and figures.

[0044]

According to the present invention, a combination of a small number of light emitting elements having high luminance and high frequency response characteristics and a deflecting means makes it possible to project a high-resolution image which is more compact than a conventional image display device. Currently HDTV and SXG
A very high resolution which is far higher than the high resolution required for A can be realized very easily. Further, simultaneous scanning of a plurality of lines and scanning in two directions can be performed by a single polygon mirror provided as a deflecting unit, so that the number of LEDs provided in a light emitting source can be significantly reduced, and the apparatus can be made more compact. Power consumption can also be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a video display device of the present invention.

FIG. 2 is a schematic view showing an arrangement of light emitting sources by R, G, and B LEDs of an LED array;

3A and 3B are details of the polygon mirror in the embodiment of FIG. 1, wherein FIG. 3A is a plan view viewed from above, and FIGS. A
Sectional view taken along line BB, line CC

FIG. 4 is a schematic diagram showing a reflection form of light from a reflection surface of a polygon mirror.

FIG. 5 is another example of an LED array, in which (a) is a schematic front view of an example in which light emitting sources are arranged in a plane on a rectangular LED array, and (b) is arranged with three LED arrays in a video display device. Schematic diagram of an example in which a luminescence source is incorporated in each

FIG. 6 is a schematic diagram showing an image of a line formed on a screen.

7A and 7B are details of a polygon mirror in which all the inclination angles of six reflecting surfaces are changed, wherein FIG. 7A is a plan view seen from above, and FIGS. 7B, 7C, and 7D are FIGS. DD line, EE
Sectional view taken along line FF

FIG. 8 is a schematic diagram showing a reflection form of light from a reflection surface of the polygon mirror of FIG. 7;

FIG. 9 is a schematic diagram of an example in which the inclination angle of the reflection surface is changed by Lorentz force while rotating the polygon mirror.

FIG. 10 is a schematic diagram showing a reflection form of light from a reflection surface of the polygon mirror of FIG. 8;

11 is a schematic diagram showing a video pattern of a line on a screen when the polygon mirror of FIG. 8 is used.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Image display apparatus 2a Signal conversion part 2b LED control part 2c Polygon mirror control part 3 LED array 3-1-3-200 Light emitting source 3a LED of R 3b LED of G 3c LED of B 4 Condensing lens 5 Optical fiber 6 Light emission Array 6a-1 to 6a-200 Condenser lens 7 Polygon mirror 7a, 7b, 7c, 7d, 7e, 7f Reflection surface 8 Distortion correction lens 9 Projection lens 10 Polygon mirror 10a, 10b, 10c, 10d, 10e, 10f Reflection surface 11 Polygon mirror 11a Support shaft 11b, 11c, 11d, 11e, 11f, 11g Reflecting surface 50 screen

Continued on front page F-term (reference) 2H045 AA04 BA23 BA33 CA33 CA54 5C058 AA13 BA05 BA25 EA02 EA12 EA13 5F041 DC83 EE04 FF03 5G435 AA00 AA03 AA16 BB04 CC12 DD04 DD09 EE29 EE30 GG02 GG26 GG26 GG23

Claims (9)

[Claims] 1. A light source for a plurality of incoherent lights which emits light in response to an input video signal, a beam diameter of a light beam emitted from the light source is narrowed, and the light beams are arranged in a uniaxial direction. Light-collecting means, light-deflecting means for deflecting the light from the light-condensing means in two axial directions, and distortion-correcting means for correcting the light from the light-deflecting means to form an optical path toward the display surface. An image display device, comprising: 2. The polygon mirror according to claim 1, wherein said deflecting means is a polygon mirror which forms a plurality of reflecting surfaces on a peripheral surface and rotates around an axis, wherein said plurality of reflecting surfaces are horizontally scanned between circumferentially adjacent ones. 2. The video display device according to claim 1, wherein the video display device has a constant angle difference so that the deflection direction of the line is displaced in the vertical direction. 3. The scanning device according to claim 1, wherein said deflecting means is a polygon mirror which forms a plurality of reflecting surfaces on a peripheral surface and rotates around an axis, wherein said plurality of reflecting surfaces are adjacent to each other in a circumferential direction in a horizontal scanning direction. 2. The image display device according to claim 1, wherein the attitude of the polygon mirror can be changed simultaneously with the rotation about the axis so that the deflection direction of the line is displaced in the vertical direction. 4. The image display device according to claim 1, wherein the light source of the incoherent light includes a plurality of monochromatic light emitting elements. 5. The image display device according to claim 1, wherein the light source of the incoherent light is an aggregate of a plurality of light emitting elements of different emission colors. 6. The image display device according to claim 5, wherein said light emitting elements emit at least red, green, and blue light. 7. The video display device according to claim 4, wherein said light emitting element is a light emitting diode. 8. The image display device according to claim 4, wherein said light emitting element is an organic electroluminescence element. 9. The light condensing means includes a bendable optical fiber as an optical path between an incident part of the light from the light emitting source and an emitting part of the light toward the deflecting means. The video display device according to any one of claims 1 to 8, wherein