JPS6113894A - Picture projecter - Google Patents

Abstract

PURPOSE:To project a picture satisfactorily with simple constitution by forming a picture projecter with use of a beam index-type color image receiving tube. CONSTITUTION:Video light beams from beam index-type color image receiving tubes 1L and 1R are projected on a screen 4 through lens systems 2L and 2R and deflection boards 3L and 3R different in deflection angles at 90 deg.. An observer views the screen 4 through eyeglasses where deflection boards 5L and 5R matching to the deflection angles of pictures are provided on left and right eyes. Consequently, pictures from two image receiving tubes 1L and 1R are independently supplied to right and left eyes of the observer, and the stereoscopic observation is executed. By utilizing a beam index-type color image receiving tubes as the image receiving tubes 1L and 1R, an extremely bright picture can be obtained through the deflection boards 3L and 3R. When a display is executed with the aid of a single video signal, the same video light beam is projected from two image receiving tubes 1L and 1R, whereby the picture can be brightened twise. In this case, the deflection boards 3L and 3R are unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image projection apparatus using a so-called beam index type color picture tube.

BACKGROUND TECHNOLOGY AND PROBLEMS For example, in aircraft, a service is provided in which the scenery seen from the cockpit is photographed with a video camera and displayed on an image projection device installed in the passenger cabin.

In that case, if the two video cameras described above are installed with a parallax and the two images taken by these cameras can be supplied independently to the passenger's left and right eyes, the passenger can see the scenery described above in 3D. It can be used as a main stake, and Sardice can be greatly improved.

Here, as a means for independently supplying two images to the left and right eyes, a method using a polarizing plate is conventionally known. In other words, polarizing plates with polarization angles different by 90 degrees are installed in front of each lens that performs projection, and the images projected through these polarizing plates are delivered to the left and right eye positions with polarized light that matches the polarization angle of the image. Perform the main stake using glasses with a board.

This allows two images to be supplied independently to the left and right eyes.

However, in the case of a conventional device for projecting a video signal as described above, the brightness of the projected image is extremely low, and when the projected image is passed through the above-mentioned polarizing plate, the projected image becomes extremely poor.

OBJECTS OF THE INVENTION In view of the above points, the present invention is intended to provide a simple structure that can always project good images.

Summary of the Invention The present invention has first and second beam index type color picture tubes, projects image light from the first and second beam index type color picture tubes onto a single screen, and projects the image light from the first and second beam index type color picture tubes onto a single screen. At one time, video signals having left and right parallaxes are supplied to the first and second beam index type color picture tubes, respectively, so that the front faces of the first and second beam index type color picture tubes are provided with polarization angles mutually. 90 degrees different polarizing plates are provided, and at other times as desired, equal video signals are supplied to the first and second beam index type color picture tubes to change the polarizing plates to the first and second beam index type color picture tubes. This image projection device is characterized by being provided with a mechanism for removing the color picture tube from the front surface, and according to the invention, a good image can always be projected with a simple configuration.

Embodiment By the way, for example, color-value light stripes of red, green, and blue are repeatedly arranged at a predetermined pitch in the horizontal scanning direction, and a light-absorbing stripe is provided between each of these color-value light stripes. For example, every other body stripe is provided with an index stripe made of a phosphor or the like. These are then scanned with a single beam, detected by a fluorescent 'i PIN diode in the index stripe, etc., and red, green, and blue video signals are sequentially switched using a signal obtained by doubling this detection signal. Color reproduction is performed by modulating the scanning beam with the video signal.
A so-called beam index type color picture tube has been proposed.

According to such a beam index type color picture tube, since a shadow mask or the like is not used, the brightness is improved with the same amount of beam, and extremely high brightness can be obtained.

Therefore, it has been proposed to form an image projection device using such a beam index type color picture tube. According to this, an extremely bright projected image can be obtained with a single picture tube.

That is, in FIG. 2, (IL) and (IR) are beam index type color picture tubes, and the image light from these is transmitted to lens systems (2L), (2R), and
The light is projected onto the screen (4) through polarizing plates (3L) and (3R) whose polarization angles differ by 90 degrees. And the main stakeholder,
The screen (4) is viewed through glasses provided with polarizing plates (5L) (5R) that match the polarization angle of the image at the left and right eye positions, respectively.

Therefore, in this device, two picture tubes (IL) (IR
) are supplied to the left and right eyes of the master stakeholder independently,
Tax collection will be done using stereoscopic vision. In this case, by using the above-mentioned beam index type color picture tube as the picture tube (LL) (IR), the polarizing plate (3LX3R
) 'Th can also be used to obtain extremely bright images.

Furthermore, in the above-mentioned apparatus, when displaying with a single video signal, it is possible to make the image twice as bright by projecting the same image light from two picture tubes (IL) and (IR). Can be done. In that case, polarizing plate (3L) (3
R) is completely unnecessary ◇Therefore, in Fig. 1, the polarizing plate (3) is attached to the rotating axis α, a rotating plate (to) is provided on this rotating axis αη, and this rotating plate (2) is attached to the rotating axis αη. ) is connected to a plunger α field and a spring α4.

For example, when the syranger α1 is driven, the rotary plate a2 rotates clockwise, and the polarizing plate (3) is moved to the position shown by the solid line. When the sylanger α1 is released, it is driven by the force of the spring The rotating plate (2) is rotated to the left, and the polarizing plate (3) is removed from the front surface of the lens system (2) as shown by the broken line.

Therefore, in this device, when a single video signal is used, the polarizing plates (3L) (3R) are removed, and a sharper image can be obtained.

Also, as shown in Figure 3, the left and right video signals supplied to the terminals (:21LX21R) are switched to switches (6L) (6R).
) is supplied to the picture tube (IL) (IR) through one fixed contact, and a single video signal supplied to the terminal (a) is supplied to the other fixed contact of the switch (6L) (6R). Ru. A driving voltage from a small voltage source is supplied to the plunger through one fixed contact of the switch (6P), and the other fixed contact of the switch (6P) is grounded.

These switches (6L), (6R), and (6P) are interlocked, and the switch (6) is provided, for example, on the back of the device, so that the user can achieve stereoscopic vision just by fully operating the switches (6). It is possible to switch between cases where this is not the case.

In this way, according to the above-described apparatus, it is possible to always project a good image with a simple configuration.

Note that although the above example is a case in which images are projected from the front side, the above-described apparatus can also be applied to cases where images are projected from the back side using a semi-transparent screen. In other words, in Fig. 4, the image light from the picture tube (IL) (IR) passes through the lens system (2LX2R), the polarizing plate (3L) (
3R), it is reflected by the mirror (7) and passes through the screen (
4) is projected from the rear side.

Also in this device, by using a beam index type color picture tube as the picture tube (ILXIR), stereoscopic viewing can be performed with extremely bright images.

By providing a mechanism for removing the folded polarizing plate (3LX3R), it is possible to display a non-stereoscopic screen even more quickly.

, Effects of the Invention According to the present invention, it has become possible to always project a good image with a simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one example of the present invention, FIGS. 2 and 3 are for explanation thereof, and FIG. 4 is a block diagram of another example. (1) is a beam index type color picture tube, (2) is a lens system, (3) is a polarizing plate, (4) is a screen, (5)
) are glasses, (6) is a switch, αη is a rotation axis, μs is a rotating plate, and αJ is a plunger.

Claims (1)

[Claims] It has first and second beam index type color picture tubes, projects image light from the first and second beam index type color picture tubes onto a single screen, and projects the image light from the first and second beam index type color picture tubes onto a single screen at a desired time. and a second beam index type color picture tube, each of which is supplied with a video signal having a left and right parallax, and a polarizing plate having a polarization angle of 90 degrees different from each other is provided in front of the first and second beam index type color picture tubes. and at other times as desired, supplying equal video signals to the first and second beam index color picture tubes to remove the polarizing plate from the front surfaces of the first and second beam index color picture tubes. An image projection device characterized by being provided with a mechanism.