JPS58106980A - Picture display - Google Patents

Abstract

PURPOSE:To obtain a bright color picture with a compact and light-weight device, by providing a multi-optical axis multiple magnifying projection optical system for obtaining an erect magnified projection real image between a color picture receiving tube and a screen. CONSTITUTION:The image obtained by, for example, a 30-inch and 90 deg. deflecting color pictue receiving tube 1 is projected onto a screen 3 through a multi-optical axis multiple magnifying projection optical system 2 for obtaining an erect magnified projection real image. In respect to the multi-optical axis multiple magnifying projection optical system 2 provided between the picture receiving tube 1 and the screen 3, three-layered lenses consisting of reducing lenses 2a, field lenses 2b, and magnifying lenses 2c arranged closely in six directions are fixed through black cells 2d having a honeycomb constitution while matching their optical axes to one another. The screen 3 has a sandwich structure where a core 3c is interposed between a projection screen 3b and a spherical focal plane 3a having the same center as the sphere of the picture receiving tube 1. Thus, the device is made compact and light-weight, and the bright picture is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image display device suitable for use in obtaining color images on a large screen, and is designed to be compact, lightweight, and provide a bright screen. At present, the ability to make color picture tubes with large lids is almost at its limit, and picture tubes are used to produce large-screen color pictures.
The screen is dark in the 0-top 4-diode, and the rear-up 4-diector has a larger K111 point.

In view of these points, the present invention aims to provide a display case that is extremely compact, lightweight, and provides a large, bright screen.

Hereinafter, an embodiment of the picture display device of the present invention will be described with reference to FIG.

In this Figure 1, (11 is, for example, a 30-inch 90
A color picture tube in the °-direction is shown, and this color picture tube 111
A multi-optical axis multi-enlargement projection optical system + 21 is used to obtain an erect enlarged projection real image (described later) from the image obtained by the IJ-n (3).
K projection to obtain a large screen color image.

The multi-optical axis multiple magnification projection optical system +21 installed between the color picture tube (1) and the screen (3) includes, for example, a reduction lens (2M), a field lens (2b), and an enlargement lens arranged in a hexagonal dense manner. A three-layer lens (2C) is used in which the optical axes are aligned and fixed via honeycomb-structured black cells (2d). When manufacturing this multi-optical axis multiple magnification projection optical system (2), for example, a reduction lens (
21), field lens (2b), magnifying lens (
A black cell (2d) with a honeycomb structure corresponding to each lens group is placed between the lens plates of lenses (2g) and (2b), which are formed by integrally molding a predetermined number of lenses of each of 2C) arranged in a planar shape. and lenses (2b) and (IC), respectively, and fixed between the lens plates. Here, the optical path in the multi-optical axis multiple magnification optical system (2) is as shown in Fig. 2.
When supplied, a reduced image is obtained at the position of the field lens (2b), and further magnified by, for example, 3 times through the magnifying lens (2C), the real image A' is projected on the screen (3) K. It becomes like this. Furthermore, as is clear from the optical path at point a shown in Figure 3, the image obtained through each unit field of view is superimposed with the image obtained from another adjacent unit field of view having a different optical axis, and the screen (3) K When projected, it becomes K. Therefore, with this multi-optical axis multiple magnification optical system (2)K, compared to the case where a magnified orthographic projection real image is obtained using one lens,
If the number of sets of three-layer lenses used is n, the angle that each lens faces becomes small, and the focal length can be approximately -LK, and since the focal length is small, the optical path as a whole is short, It is also known that brightness with an aperture ratio close to 10 can be obtained.

In addition, the enlarged orthographic projection real image of the color picture tube (1) +l
) and a projection screen (3b) made of a transparent plastic plate, which is concentric with the sphere of the fluorescent surface (11), and a projection screen (3b) made of a transparent glass plate, each core having a diameter of, for example, 1. It has a sand inch structure sandwiching Aluo's expanded core (3C) with a honeycomb structure of .5 strips. A so-called honeycomb-made rear agrozier screen is used. Incidentally, when the image forming surface of this screen (3) is converted from a spherical surface to a flat surface, the image distortion caused by K is corrected in advance by applying pincushion distortion in the color picture tube i1).

In this embodiment configured in this way, the color picture tube +17
The light from the spherical fluorescent surface (1 m) of
2b) A magnification of, for example, 3 times is projected onto the spherical imaging surface (3a) of the screen (3) through the magnifying lens (2C), and after being exposed to the expanded core (3C), it is exposed to a transparent plastic flat plate. Since the image is projected onto the projection screen (3b), it is possible to obtain an image on the flat projection screen (3b) that is approximately three times as large as the image of the picture tube (1) of the television. In this case, the multi-optical axis multiple magnification optical system (2) is linked to the color picture tube (υ) and the screen (3) at a desired position to obtain a large image. As is clear from the optical path, the image obtained through each unit field of view is superimposed with the image obtained from the adjacent unit field of view having a different optical axis, and the screen (3)
projected on.

Therefore, when the multi-optical axis multiple magnification optical system (2) is used in conjunction with a series of t, compared to the case where an enlarged orthographic projection real image is obtained with one lens, if the number of sets of three-layer lenses used is n, The angle at which each lens faces becomes smaller, and the focal length becomes substantially higher.As the focal length becomes smaller, the optical path becomes shorter due to the metal body, and a large image with brightness close to 1.0 can be obtained.

As mentioned above, according to this example, the real image is displayed on the screen (3
)K For example, a 3x normal text enlargement projection can be obtained. In addition, the overall shape can be made almost similar to a normal picture tube, and by shortening the optical path, it is possible to obtain a compact, lightweight double-image display device that is impossible with a normal single-optical-axis image display device. In addition, since it goes through the multi-optical axis multiple magnification projection optical system (21), the projection of the screen (3) is also bright.In addition, the wider the lens, the more the screen can obtain. There is an advantage in that the screen (3) can be made brighter, and there is also an advantage in that the screen (3) has the effect of giving directionality to the projected light beam with respect to the front viewing area.

It goes without saying that the present invention is not limited to the above-described embodiments, and can take various other configurations without departing from the gist of the present invention.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of an embodiment of the image display device of the present invention, Figure 2
@ and FIG. 3 are diagrams for explaining essential parts of an embodiment of the present invention. (IJ is a color picture tube, (2) is a lens cup as a multi-optical axis multiple magnification projection optical system, (21) is a reduction lens, (z
b) is a field lens, (2C) is a magnifying lens Xs
(!d) is a black cell, and (3) is a screen. Same as Hide Matsukuma Pass.

Claims (1)

[Claims] A screen is arranged in front of the picture tube, and a multi-optical axis multi-enlargement projection optical system is provided between the picture tube and the screen to obtain an erect enlarged projection real image on the screen. Image display device.