JPS5911306B2 - Projection type multiple image synthesis device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a projection type multiple image compositing device 15 that erases a part of an image projected on a screen and projects another image into the space left after the image is erased. be.

Television receivers that simultaneously display images of two different channels on the image receiving surface of a single cathode ray tube have recently been commercialized.

In these receivers, a part of the video signal of the main channel is erased, the scanning lines of the video signal of 20 channels of the sub channel are sampled and stored at appropriate intervals, and the video signal of the sub channel stored during the erased period mentioned above is stored. I am trying to insert it and display it. In this case, the image of the main channel will be a large screen, and the image of the sub channel will be a small screen, and both 25 screens will be formed by scanning simultaneously with the electron beam. For this reason, the number of scanning lines forming a small screen is smaller than that of a large screen, and the number of pixels of an image is also smaller, resulting in a deteriorated image quality. In order to improve this problem, if the screen occupied by the inserted image is made larger, the number of erased portions occupied by the large screen increases, making it difficult to understand the contents. The present invention has focused on the above-mentioned problems, and is designed to simultaneously display images obtained from each image generation source that provides two different pieces of information 35 on one screen using means completely different from conventional means. be.

The present invention provides a projection type video display device that has a video generation source that obtains video information based on a video signal as a reproduced image using a cathode ray tube, and projects the reproduced image onto a screen using a lens or a magnifying glass to display an enlarged image; That is, this was achieved by developing the technology of a device commonly called a "video projector." In addition to the above-mentioned projection type video display as a component, the present invention also provides a space for erasing part of the information of the enlarged image projected on the screen, so that the reproduced image on the cathode ray tube as the video source is adapted to an image erasing means for substantially erasing a portion of the image, a second image generating source different from the aforementioned image generating source, and projecting an image of the second image generating source onto an enlarged image erasing space on a screen. A second lens or a magnifying glass is provided. The present invention will be best understood with reference to the embodiments shown in FIGS. 1 and 2.

Therefore, the present invention will be explained below based on examples. FIG. 1 is a block circuit diagram showing the configuration of a unit 3 that generates images in a projection type multiple image synthesizing device.

Here, 1 is a part meaning a video signal generation source from which a color video is obtained. Further, 2 means another signal generation source for obtaining another black-and-white q image. The first video source 1 reproduces the video and audio of a selected channel of television broadcasting received by the antenna 5 (hereinafter referred to as the "main channel"), and the second video source 2 Preferably, the main channel and another channel (hereinafter referred to as "subchannel")
It plays video and audio of In the signal generation source 1, 7 is a tuner, where the video intermediate frequency signal of the main channel is selectively converted and applied to the video intermediate frequency amplifier 8. Next, the output of the amplifier 8 is subjected to image detection by an image detector 9, and is then applied to a color demodulation/image amplification circuit 11 via an image excitation stage 10 as a composite image signal. The output of the circuit 11 is R, G, and B color signals, which are applied to the respective cathode ray tubes 16, 17, and 18. Reference numeral 12 denotes a synchronization separation circuit, a horizontal/vertical deflection circuit, and a high voltage generation circuit, which separates the horizontal and vertical synchronization signals from the composite video signal. , 17, 18, and generates high voltage to be applied to the anode of each cathode ray tube. 13 is an image erasing signal generator; the circuit 12
A signal for erasing the video signal of a predetermined period of the field and line is generated based on the synchronization signal given from the sync signal, and this signal is given to the video amplifier 11.

Schmitt lenses 19, 20 and 21 are arranged on the image receiving surfaces of the cathode ray tubes 16, 17 and 18.

Further, the signal taken out from the video intermediate frequency amplifier 8 is given to the audio reproduction system circuit 14, and is generated as audio by the speaker 15. In FIG. 1, a video generation source 2 for extracting a sub-channel video is also similar to the first generation source 1, including a tuner 23, a video intermediate frequency amplifier 24, a video detector 25,
It consists of a video excitation stage 26, a video amplifier 27, a synchronous separation/deflection and high voltage generation circuit 28, a cathode ray tube 29, an audio reproduction system circuit, a speaker 31, and the like.

Further, a magnifying lens 32 is arranged in front of the image receiving surface of the cathode ray tube 29. In this embodiment, the video source 2 of the sub-channel is used to reproduce a black and white image, but the same effect can be obtained even if a color reproduced image is obtained in the same way as the video source 1. The same thing applies if 1 is used for black and white. It goes without saying that each of the block circuits shown in FIG. 1 is a well-known circuit. Therefore, detailed connections within these individual circuits are well-known in well-known literature, and therefore will not be illustrated here. Each cathode ray tube 16, 17,
The images focused on the image receiving surfaces of lenses 18 and 29 are
Images 9, 20, 21 and 32 are projected onto one projection screen.

The state at this time is shown in the perspective view of FIG. In FIG. 2, the image reproduced on the image receiving surface of the three-color cathode ray tube in the unit 3 is transmitted through the Schmitt lens 1 placed in front of it.
9, 20 and 21, and is projected onto almost the entire image receiving surface 34 of the screen 33.

That is, taking the lens 20 that projects a green image as an example, its state forms a surface surrounded by the four corners reached by arrows A, b, c, and d. When projecting the sub-channel image on the same screen 33 at the same time as the enlarged image of the main channel to obtain a composite image, information in a part of the section 35 of the main channel image 34 is erased to form a space that does not shine. . Then, in place of that space, the image of the sub-channel is projected onto the section 35 through the magnifying lens 32 and forms an image.
That is, the portion surrounded by the four corners reached by the arrows E, f, g, and h becomes the inserted image of the sub-channel. In the case of the above embodiment, both the large image on the main channel and the small image on the sub channel can be displayed as they are, as they are reproduced with the standard number of scanning lines for television broadcasting, so there is no loss in their resolution. You won't be disappointed.

Regarding audio reproduction, the audio from both channels may be emitted from the speakers at the same time, but it may also be possible to switch to either one using a switch, or to reproduce the audio from the sub-channel using earphones or the like. In addition to the embodiments described so far, the invention makes it possible to provide several modified embodiments.

As one of them, we will focus on image erasing means for erasing a part of the reproduced image of the first video source. Instead of using the erase signal generator 13 in FIG. 1, mechanical means can be used. This is to arrange the same type of mask 41 at the same position in front of the image receiving surfaces of the cathode ray tubes 16, 17, and 21, as representatively shown in FIG. 16' is a reproduced image. Of course, for a black-and-white type video source that uses only one cathode ray tube or a color cathode ray tube that has a shadow mask, only one mask is sufficient. This mask 41 is operable from outside the apparatus cabinet so that it can be placed at a predetermined position on the image receiving surface only when images are to be combined. Their specific structures will be easily realized. Also, of the configuration shown in FIG.
It is possible to replace the combination of the image source 2 and the lens 32 part with another one, for example a film projector.

In that case, the first video generation source 1 may obtain a reproduced image based on a video signal provided from a device such as a video recorder or a video disk. In this way, additional information such as explanations, annotations, etc. of the content of the enlarged large image can be provided from the second video source 2 to the blank space on the screen, making it convenient for the present invention to be used in education. good. As described above, according to the present invention, images can be combined optically and viewed and used simultaneously on one screen.

Furthermore, since the screen used is sufficiently larger than the image receiving surface of the cathode ray tube of a typical television receiver, the size of the inserted image can also be made large enough to satisfy the viewing experience. As a result, it is less likely that the main large-scale image will lack information content and become incomprehensible. Note that the insertion position on the screen is not limited to the position shown in the drawings of the embodiment, and can be arbitrarily selected.

[Brief explanation of drawings]

FIG. 1 is a block circuit diagram showing one embodiment of the unit 3 on the video generation source side of the projection type multiple image synthesizing device of the present invention, and FIG.
The figure is a perspective view for explaining the appearance and operation of the apparatus of the present invention, and FIG. 3 is a front view showing a cathode ray tube image receiving surface for explaining another embodiment of the present invention. 1 and 2...Video generation source, 13...Video erasing signal generator constituting the image erasing means, 41...Mechanical mask showing another example of the image erasing means, 19-21 and 32
···lens.

Claims (1)

[Scope of Claims] 1. A projection type video having a video generation source that obtains video information based on a video signal as a reproduced image by a cathode ray tube, and projecting the reproduced image onto a screen using a lens or a magnifying glass to project an enlarged image. In the display device, an image erasing means for substantially erasing a corresponding part of the reproduced image on the cathode ray tube of the image generation source to provide a space in which part of the information of the enlarged image projected on the screen is erased; , comprising a second image generation source different from the image generation source, and a second lens or magnifying glass for projecting an image of the second image generation source onto an enlarged image erasure space on the screen. A projection type multiple image synthesis device characterized by: 2. The method according to claim 1, characterized in that one of the video generation sources generates a video of one selected channel of television broadcasting, and the other of the video generation sources generates a video of a different channel. Projection type multiple image synthesis device. 3. The projection type multiple image composition apparatus according to claim 1, wherein the combination of the second image generation source and the second lens or magnifying glass is a film projector. 4. The projection type multiple image composition apparatus according to any one of claims 1 to 3, wherein the image erasing means operates to erase a part of the video signal using an erasing signal. 5. The projection type plurality according to any one of claims 1 to 3, wherein the image erasing means comprises a mask provided to cover a part of the image receiving surface of the cathode ray tube. Image synthesis device.