JPH0451788A - Projection display device - Google Patents

Abstract

PURPOSE:To eliminate a troublesome operation in the case of replacement of a lens by applying aspect ratio conversion to a plural input video signals with a 1st aspect ratio by means of a control means, displaying separately the resulting signals onto an optical image generating section and projecting the signals onto a projector screen via the aspect ratio conversion lens. CONSTITUTION:A digital signal is fed from each of A/D converters 11-14 to each of picture memories 15-18. A controller 6 controls write/read to the picture memories 15-18 to attain compression processing as above. A control signal to obtain a picture is fed to the three picture memories 16-18 from the controller 6 thereby applying other processing from that of the picture memory 15. For example, the 3/4 compression processing for the lateral axis is implemented by thinning one sample from four samples or applying interpolation processing to obtain 3 samples from 4 samples at readout of the picture data from the picture memories.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a projection type display device that enlarges and projects image information for display.

B0 Summary of the Invention The present invention projects an image of a first aspect ratio displayed on an optical image generator onto a projection screen via an aspect ratio conversion lens, thereby displaying the image as an image of a second aspect ratio. In a projection type display device, writing/reading control is performed on at least a plurality of image memories, and a plurality of input video signals having a first aspect ratio are converted from a plurality of input video signals having a first aspect ratio to a second aspect ratio in accordance with attachment of the aspect ratio conversion lens. Perform image conversion at the rate of conversion to the first aspect ratio,
By dividing and displaying these multiple images on the display surface of the optical image generating section and projecting the image of the optical image generating section onto the projection screen via an aspect ratio conversion lens, a screen screen having a second aspect ratio is created. A plurality of images having a normal first aspect ratio are displayed in a divided manner.

C0 Conventional Technology Recently, there has been a tendency for CRT (cathode ray tube) displays to have large screens that give a sense of realism. ), a feeling of being integrated with the image (Pi-sensation)
This is an extremely important factor in producing psychological effects and enhancing psychological effects. Reflecting this trend, projection-type display devices display movie video software in a large size on a projection screen, and are used in video theaters and the like.

Movies fully incorporate the above-mentioned psychological effects, and generally, as screens become larger, the ratio of the horizontal direction to the vertical direction of the projection screen becomes larger. In other words, the aspect ratio, which represents the ratio of the vertical to horizontal dimensions of the screen, is
There are standards such as standard (1: 1.38), wide screen (1: 1.85), and so-called cinema scope (1: 2.35). Here, the sense of realism,
In order to obtain horizontally long images such as the above-mentioned widescreen, which have high psychological effects such as stereoscopic effect, in the field of movies, special films such as so-called 70mm film, which corresponds to the aspect ratio of the above-mentioned horizontally wide screen, are used. 2. Description of the Related Art A method is known in which a horizontally long film is used and an image taken on the horizontally long special film is enlarged and projected as it is to display a screen with a horizontally long aspect ratio. In addition, as another method, an aspect ratio conversion optical system is used to transfer a horizontally elongated image having a second aspect ratio such as the above-mentioned wide screen onto a commonly used standard first aspect ratio, such as a so-called 35 mm film. By compressing the image in the horizontal direction using a so-called wide lens, etc., and enlarging it laterally using an aspect ratio conversion optical system (such as a so-called wide compatible lens) during projection, a second aspect ratio that is longer in the horizontal direction is obtained. A method of projecting and displaying an image is known.

By the way, in the field of image display using video signals as well, from the above-mentioned point of view, a horizontally long large screen display is desired, and in order to realize this horizontally long screen, there are roughly two methods similar to those used for movies. is considered. That is,
One method that corresponds to the former method in the case of movies mentioned above is one in which the video signal standard (format) itself has a horizontal aspect ratio, and the other method corresponds to the latter method, in which the video signal standard (format) itself is set to a horizontal aspect ratio. Without changing the format itself, by performing some aspect ratio conversion processing such as using a wide compatible lens during display, the final display screen has a horizontally long aspect ratio.

Here, the latter method is a method mainly used in projection-type display devices that display an optical image generated by an optical image generating section by projecting it onto a projection screen via a projection lens. Specifically, for example, at the shooting stage, an aspect ratio conversion optical system such as a wide lens is attached to the video camera, and the horizontally long imaging range on the subject side with the second aspect ratio is converted into an image with the standard first aspect ratio. This is optically converted (horizontal axis compression) into the image and recorded on a recording medium such as a videotape.When recording, an aspect ratio conversion optical system such as a wide lens mentioned above is used in the optical system. By doing so, it is possible to use a video camera having an image pickup unit in a format of a normal first aspect ratio, for example, a format of the NTSC standard television system, and also use a VTR (video tape recorder) of a normal NTSC system. be able to. The recorded video signal conforms to the NTSC format, but the optical image is converted from the second aspect ratio to the first aspect ratio and is an image compressed on the horizontal axis.

When reproducing a recording medium imaged using such a special method, the optical image of the first aspect ratio (however, the horizontal axis compressed image) reproduced by the optical image generating section is used with a wide-angle compatible lens, etc. By projecting the image onto a projection screen via an aspect ratio conversion (horizontal axis enlargement) optical system, an image with a second aspect ratio that is longer than the original image is displayed. This method requires a special soft tape or the like on which an image of the second aspect ratio is laterally compressed and recorded as an image of the first aspect ratio.

D0 Problems to be Solved by the Invention By the way, in the case of general television broadcasting video signals, etc., they are not converted using an aspect ratio conversion (horizontal axis compression) optical system such as the wide lens mentioned above, and this When such a normal video signal is input to a projection/shooting display device equipped with an aspect ratio conversion optical system such as the above-mentioned wide-angle compatible lens, it will be displayed as an image with only the horizontal axis enlarged.

For example, FIG. 2 shows an image 100 normally displayed with a first aspect ratio (a:b=3=4) in a normal NTSC television signal, and the video signal with this first aspect ratio is input to a projection display device, the second aspect ratio (c:d=9:16) shown in FIG. 3 is obtained by projecting and displaying through an aspect ratio conversion lens such as a wide compatible lens Projected image 1 of
01 is displayed, and only the horizontal component becomes a horizontally long image (4/3) times, and a normal projected image cannot be obtained.

Therefore, when monitoring a television broadcast signal having the current standard first aspect ratio, it is necessary to replace the lens with a standard lens (a general magnifying projection lens that does not perform aspect ratio conversion).

However, if you are constantly projecting a wide screen using the wide shooting software mentioned above, and you are using the system to display television broadcasts for a short period of time between projections or to monitor only news, you may need to use the lens each time. It is complicated to replace.

Therefore, in view of the above-mentioned problems, the present invention projects an image of a first aspect ratio displayed on an optical image generating section onto a projection screen via an aspect ratio conversion lens, thereby changing the image to a second aspect ratio. Provided is a projection display device that displays an image at the aspect ratio of the screen format corresponding to each input signal, without the complicated operation of replacing and attaching a lens compatible with the screen format. The purpose is to

When the attachment of the aspect ratio conversion lens is detected, the second aspect ratio is changed to the first aspect ratio by controlling the writing/reading of a plurality of input video signals to each image memory. The method is characterized in that the plurality of images are simultaneously displayed on the display surface of the optical image generating section by performing image conversion at the ratio of the conversion, and the plurality of images having the first aspect ratio are displayed on the projection screen. It is something.

E,! I! Means for Solving the Problems In order to solve the above-mentioned problems, the projection type color display device according to the present invention converts the image of the first aspect ratio displayed on the optical image generator through an aspect ratio conversion lens. In a projection type display device that displays an image of a second aspect ratio by projecting it onto a projection screen, there is provided a means for detecting attachment of the aspect ratio conversion lens, and a writing/reading control for at least a plurality of image memories. , and a control means whose control operation is switched in accordance with the detection output from the detection means, and according to the present invention, the control means F9 controls the plurality of input video signals of the first aspect ratio to the control means. By converting the aspect ratio and displaying the divided images on the optical image generating section, and projecting the images onto the projection screen via the aspect ratio conversion lens, a plurality of the first aspect images are displayed on the screen display surface of the second aspect ratio. Images with normal ratios are displayed separately. Also, in terms of operation, since the attachment of the aspect ratio conversion lens is automatically detected and the above display is performed, the effort of switching operations can be saved.

G. Examples Examples of the present invention will now be described in detail with reference to the drawings.

In this embodiment, the first aspect ratio is the standard NTS
Aspect ratio of screen of C method: 3:4=1:(4/3)! ;1:1.
33 and as the second aspect ratio, 9:
l6=1: (16/9) #1: 1.78
is used. This second aspect ratio is horizontally longer than the aspect ratio of the standard screen, and is also used as a type of aspect ratio in recent high-definition television (HDTV) systems.

First, FIG. 1 shows a schematic configuration of the main parts of an embodiment of a projection type display device according to the present invention, and the aspect ratio conversion lens used in this projection type display device has an optical image generating section
first aspect ratio (3:4) generated in
This is a magnifying projection lens for projecting an image of a second aspect ratio (9:16) onto a projection screen. A switch 2 is provided as means for detecting attachment of the aspect ratio conversion lens 1. Each input terminal 7~
A plurality (four systems) of video signals having the first aspect ratio are input to the IO, and each of these input video signals is converted into a digital signal by the A/D converters 11 to 14, respectively. The images are stored in each of the image memories 15 to 18, respectively. These image memories 15~
Writing/reading processing of video signals for 18 is performed by a controller 6 which is a control means. The controller 6 performs image processing including aspect ratio conversion processing for converting the second aspect ratio to the first aspect ratio in accordance with the output from the switch 2 (output for detecting attachment of the lens 1). Writing to each image memory 15 to 18/
This is achieved by performing read control, switching control of the select switch 19, and write/read control for the field memory 20, and converts it into an analog signal with the D/A converter 21 and sends it through the output terminal 22 (not shown). By sending the converted images to the optical image generating section, the plurality of converted images are displayed simultaneously in an optical image generating area of the first aspect ratio of the optical image generating section. In each of these split-displayed images, the video signals of the first aspect ratio from the input terminals 7 to IO are divided from the second aspect ratio to the first aspect ratio.
The image is converted to an aspect ratio of , and is also reduced as necessary to fit into each divided area within the entire optical image generation area. By projecting the optical image generated by this optical image generating section onto the projection screen via the aspect ratio conversion lens 1, a plurality of the above-mentioned A normal image with an aspect ratio of 1 (an aspect ratio of 3:4 in the normal NTSC system) is displayed dividedly (so-called multi-screen display).

Here, as shown in Figure 1, an aspect ratio conversion lens (
When the wide-angle compatible lens (1) is attached, the switch 2 is turned on, and aspect ratio conversion processing for each input video signal is automatically performed. That is, the voltage supplied from VOO to the input terminal 3 of the inverting buffer 5 via the resistor 4 is changed to (8) due to the conduction of the switch 2. (low level) state, and the input of the inversion buffer 5 also becomes low level state. Therefore, the output of the inversion buffer 5 becomes high level. The controller 6 has A/D converters 11 to 14, image memories 15 to 18, and
The select switch 19, field memory 20, and D/A converter 21 are controlled respectively. Input terminals 7-1
A normal NTSC broadcast signal having an aspect ratio of 3:4 is input as the first aspect ratio.

However, this input video signal is a signal whose first aspect ratio has not been subjected to horizontal axis compression applied by an aspect ratio conversion optical system (for example, a wide lens).

Therefore, image signal processing including processing to convert from the second aspect ratio to the first aspect ratio is required, and in order to realize this by digital signal processing including write/read control for the image memories 15 to 18, input terminals 7-10
The signals input from the A/D converters 11 to 14 respectively
is converted into a digital signal. At this time, signals for controlling each A/D converter 11 to 14 are also supplied from the controller 6.

As described above, by performing the same amount of horizontal axis compression as the horizontal axis compression received by the aspect ratio conversion optical system in the circuit within the projection display device, these images are generated within the entire display surface of the first aspect ratio of the optical image generating section. Multiple converted images can be displayed simultaneously.

Here, the compression ratio when converting from the second aspect ratio of 9:16 to the first aspect ratio of 3=4 is that the first aspect ratio is 9 when the vertical axis is adjusted to the same ratio. :
Considering that 12, only the horizontal axis is 12/l 6=
The ratio may be set to 3/4 compression. Specifically, for example, the compression ratio in the horizontal direction is set to 75%, and the compression ratio in the vertical direction is set to 10%.
Set to 0% (no compression). At this time, the input image 100 with the first aspect ratio (a:b=3:4) as shown in FIG.
Image 1 with an aspect ratio of 1 (a:e=3:3) shown in the figure
03, and this image 103 covers the entire display surface 10 of the first aspect ratio (a:b=3:4) of the optical image generating section.
It is displayed in a form inscribed within 2. Here, within the entire display surface 102 of the optical image generating section shown in FIG.
In addition to the image 103 with e=3:3, the image with the same aspect ratio (=
1) and further reduced overall images 105 to 10
7 is displayed. Each of the dimensions of these images 105 to 107 is g equal to each other in the horizontal direction, and each dimension in the vertical direction is also equal to r. The ratio of each dimension a and width is a:b:f:g=3:4:1:1, that is, the area of the entire display surface 102 excluding the image 103 is vertically Divide into 3 to create multiple images 1
05 to 107 will be displayed. In addition, image 10
5 to 107, at the same time (or before or after) the above aspect ratio conversion process is applied to each of the three input video signals so that only the horizontal axis is compressed to 3/4.
, image conversion processing is performed to compress both the vertical and horizontal axes of the entire image to 1/3 (to 1/9 in area ratio). In other words, in the end, the vertical axis becomes 1/3 and the horizontal axis becomes 1/3.
It is compressed to 4.

In the circuit shown in FIG. 1, digital signals are sent from each of the above-mentioned A/D converters to each of the image memories 15 to 18, respectively. The controller 6 controls writing/reading to and from each image memory 15 to 18, thereby performing the above-described compression processing. Three of these image memories 16 to 18 are supplied with control signals from the controller 6 for obtaining the images 105 to 107, and the image memories 1
Processing different from step 5 is performed. Specifically, when reading image data from memory, for example, by thinning out 1 sample out of 4 samples, or by performing interpolation processing to obtain 3 samples from 4 samples, 3/4 of the horizontal axis can be reduced.
Compression processing can be performed. This may be done when writing to memory.

Further, compression of 1/3 on the vertical axis, 1/4 on the horizontal axis, etc. can be similarly performed. The compressed and converted image data read from Memo+715 to 1B in this way is
Sent to 9th. The select switch 19 selects the image memory in response to a control signal from the controller 6 and switches the image data so that the image 102 is displayed. This switching creates three images 105 in the vertical direction from the image 103.
Control is performed to switch the data in the line memory in the order of steps 1 to 107, and one field of the screen 102 is input to the field memory 20 by the write/read control signal from the control 6, read out field by field, and then D/A. converter 2
1, and the D/A converter 21 converts this input digital signal into an analog signal. The above field memory 2o and D/A converter 21 are controlled by a write/read clock and a D/A conversion clock signal from the controller 6. Note that the image conversion processing may be realized by switching control of the select switch 19 and writing/reading control for the field memory 2o. In this case, the image memories 15 to 1B are line memories or the like. The output analog signal from the D/A converter 21 is the display word that becomes the optical image generator from the blade terminal 22! For example, the optical image is supplied to a liquid crystal panel (not shown), and four images 1 as shown in FIG. 4 are displayed on its optical image display surface.
An image 102 of the first aspect ratio in which images 03.105 to 107 are divided and displayed is obtained.

Next, the image 102 displayed on the display surface of this optical image generating section
is subjected to aspect ratio conversion by the aspect ratio conversion lens (wide compatible lens) 1 such that only the horizontal axis is enlarged to 4/3, and at the same time, the entire length and width are enlarged at the same ratio and projected.

Therefore, an image 112 with a second aspect ratio (9:16) as shown in FIG. 5, for example, is displayed on the screen surface, and this image 112 consists of one large image 113 and three Small images 115 to 117 are displayed separately (so-called multi-screen display). These projected images 113 and 115~
117 is the image 103 and 105 at the optical image generating section.
to 107, respectively. Aspect ratio conversion during projection is performed using a ratio of 4/3 on the horizontal axis only, so the vertical and horizontal dimension ratio of the entire screen display surface is c:d=
Image 1 compared to 9:16 (second aspect ratio)
13 aspect ratio C:h, each aspect ratio i of each image 115 to 117;'' is c:d:h:i:j=9:16:12:3:
It becomes 4. That is, the aspect ratio C:h of the image 113 is 9:
12, the first aspect ratio is 3:4, and each aspect ratio i:J of each image 115 to 117 is also 3:4.
This is the first aspect ratio. That is, these four images 113, 115 to 117 all have the aspect ratio of the first aspect ratio 3:4,
Not compressed according to the NTSC standard television system (
@1 The image has a normal aspect ratio relationship.

In this way, the standard television video signal having the first aspect ratio is subjected to image conversion including aspect ratio conversion processing of converting the ratio from the second aspect ratio to the first aspect ratio. An aspect ratio in which an image is simultaneously divided and displayed within a display area of a first aspect ratio, and the image is converted from the first aspect ratio to a second aspect ratio through an aspect ratio conversion optical system such as a wide-angle compatible lens. By performing ratio conversion and projecting and displaying on a screen, so-called multi-images are created in which multiple uncompressed images with a first aspect ratio are divided and displayed on a screen display surface with a second aspect ratio. can be displayed.

If the signal input to the projection display device is the above-mentioned horizontally compressed signal from a dedicated soft tape, etc., it is sent as is to the optical image generation section and used with an aspect ratio conversion optical system such as a wide-angle compatible lens. By projecting the image onto the screen through the mirror, an image with a normal vertical-horizontal relationship of the second aspect ratio can be obtained. That is, for example, when a reproduced video signal input from a VTR is supplied, it is sent to the display screen of the optical image generator without passing through the circuit explained in FIG. 1 above, and a standard television signal from a tuner etc. is supplied. In some cases, automatic switching may be performed in accordance with the video signal source so that horizontal axis compression (aspect ratio conversion) processing is performed by the circuit shown in FIG.

The present invention is not limited only to the above-mentioned embodiments,
The specific numerical values of the first aspect ratio and the second aspect ratio are not limited to the numerical values in the above embodiments, and even if other aspect ratio conversion lenses are used, the compression of the first aspect ratio and the aspect ratio can be improved. A similar special projection display can be achieved by compressing the image using an electric circuit and controlling it with the same configuration, taking into account the relationship of magnification by the conversion lens.

H4 Effects of the Invention As is clear from the above explanation, according to the projection type display device according to the present invention, within the image generation display surface of the optical image generation section having the first aspect ratio, there is a difference between the second aspect ratio and the second aspect ratio. A plurality of images whose aspect ratios are converted to the first aspect ratio are displayed separately, and by projecting this optical image onto the projection screen via the aspect ratio conversion lens, the second aspect ratio is converted to the first aspect ratio. within the screen display area of
Multiple normal (normal aspect ratio)? j! Several images are displayed separately. At this time, since attachment of the aspect ratio conversion lens is detected and the display state is automatically switched to the above display state, complicated operations can be avoided.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a schematic configuration of essential parts of an embodiment of a projection type image display device according to the present invention, FIG. 2 is a diagram showing an image of a first aspect ratio, and FIG. 3 is a diagram showing a second aspect ratio. Figure 4 is a diagram showing an image obtained by enlarging and projecting an image on a screen using an aspect ratio conversion lens and displaying it as a second aspect ratio. FIG. 5 is a diagram showing an image obtained on the display surface of the optical image generating section, and FIG. 5 is a diagram showing an image obtained by enlarging and projecting the optical image of FIG. 4 onto a screen via an aspect ratio conversion lens.

Claims (1)

[Claims] A projection type display that displays an image of a first aspect ratio displayed on an optical image generating section as an image of a second aspect ratio by projecting it onto a projection screen via an aspect ratio conversion lens. In the apparatus, means for detecting attachment of the aspect ratio conversion lens, a plurality of image memories for respectively storing a plurality of input video signals, and a control for performing write/read control on at least the plurality of image memories. means for controlling the writing/reading of a plurality of input video signals of the first aspect ratio in each image memory when the detection means detects that the aspect ratio conversion lens is attached. , perform image conversion including aspect ratio conversion processing for converting these input video signals from the second aspect ratio to the first aspect ratio, and display these converted images on the display surface of the optical image generation unit. control means for simultaneously displaying a plurality of images in divided form; projecting the image of the optical image generating section onto the projection screen via the aspect ratio conversion lens;
A projection type display device, characterized in that an image having an aspect ratio of 1 is divided and displayed on the projection screen.