JP4137344B2 - Video display device for vehicle rear seats - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the field of video display devices, and particularly relates to a video display device for a rear seat of a moving body.
[0002]
[Prior art]
FIG. 8 is a block diagram showing a conventional moving body rear seat video display device. This is a diagram showing an example of an installation form of the in-vehicle rear seat wide television system. The display unit 101 for displaying video is installed near the center of the ceiling 104 in the passenger compartment so that the passenger 103 seated in the rear seat 102 can appreciate it, and has a folding structure with the upper end as a fulcrum. Operation is possible. For example, a 7-inch wide TFT (Thin Film Transistor) driving color LCD (Liquid Crystal Display) is used for the display unit 101.
[0003]
Next, the operation will be described.
FIG. 9 shows a cross-sectional view of this conventional moving body rear seat video display device.
The opening / closing operation of the display unit 101 is performed manually, and when the adjacent open button 105 is pressed, the display surface of the display unit 101 opens to an angle of about 45 degrees from the ceiling surface of the ceiling unit 104 by gravity. From this position, the display unit 101 is manually opened to an angle of about 110 degrees that is fixed in an open state. When the display unit 101 is closed, the display unit 101 is manually folded to the ceiling surface and pushed into the storage unit, so that the display unit 101 is horizontally fixed to the ceiling surface by a lock mechanism interlocked with the open button 105. An open / close detection sensor 106 that detects the open / close state of the display unit 101 is installed adjacent to the open button 105. When the display unit 101 is opened, the LCD is turned on to display an image, and conversely, The power is cut off and the image disappears.
[0004]
In this in-vehicle rear seat wide television system, various images such as a television image from a television tuner, a video image from a video deck, and a navigation image from a navigation unit can be displayed. In addition, an on-screen display function for superimposing numerical information such as a television broadcast reception channel number and a playback volume level on the display image of the display unit 101 is provided.
[0005]
[Problems to be solved by the invention]
The conventional moving body rear seat video display apparatus as described above has a structure in which the display unit 101 made of an LCD is directly suspended near the center of the ceiling unit 104 as shown in FIG. For this reason, when the driver 108 seated on the front seat 107 of the vehicle confirms the rear by using the rearview mirror 109 or direct view, the display unit 101 blocks the field of view, which makes it difficult to confirm the rear. . Further, when the occupant 103 seated on the rear seat 102 of the vehicle sees the front background through the windshield 110, the display unit 101 blocks the field of view, which makes it difficult to check the background. Further, when the display unit 101 is enlarged to achieve a large screen display, the above problem further increases, and there is a problem that it is difficult to display a video on a large screen.
[0006]
The present invention has been made to solve the above-described problems, and can display a large screen image on the rear seat of the moving body, and at the same time, easily confirm the background outside the moving body and view the scenery. An object of the present invention is to obtain a moving body rear seat video display device.
[0007]
[Means for Solving the Problems]
In the vehicle rear seat video display device according to the present invention, the video horizontal reversing means for reversing the left and right of the video in the video signal processing, and the video left and right installed near the center of the ceiling in the vehicle compartment. a video display means for displaying an image which is horizontally inverted by the inverting means and disposed below the movies image display means for reflecting the image is obtained by such a reflective transmission means for transmitting the background.
[0009]
Further, in the vehicle rear seat video display device according to the present invention, the video display means installed near the center of the seat floor in the vehicle interior with the display surface facing up, and the video display means installed above the video display means. Video left / right reversing means comprising a reflection / transmission means for transmitting an image output from the display means and a total reflection mirror optically and totally reflecting the image transmitted by the reflection / transmission means installed near the center of the ceiling in the vehicle interior The image output from the video left / right reversing means is reflected by the reflection / transmission means and the background is transmitted .
[0010]
In the vehicle rear seat video display device according to the present invention, video enlargement means for enlarging the video is provided.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a moving body rear seat video display device according to Embodiment 1 of the present invention. In FIG. 1, a display unit 1 as an image display means for displaying an image is attached in the vicinity of the center of a ceiling portion 2 in a vehicle compartment, with the display surface facing down, horizontally with respect to the ceiling surface. The display unit 1 uses an LCD or the like that is thin and does not take up space, thereby reducing the area occupied in the vehicle interior. Further, below the display unit 1, a half mirror 3 serving as a reflection / transmission unit that reflects the image displayed on the display unit 1 and transmits the background is approximately 45 with respect to the display surface of the display unit 1. It is installed so as to hang from the ceiling portion 2 so as to form an angle of degrees .
[0012]
Since it is configured in this way, the occupant 5 seated on the rear seat 4 visually recognizes the image of the display unit 1 reflected by the half mirror 3 and passes through the windshield 6 and passes through the half mirror 3. You will also see the background. In addition, the driver 8 of the vehicle seated on the front seat 7 sees the rear background that is transmitted from the rear half mirror 3 and reflected by the rearview mirror 9.
[0013]
FIG. 2 is a characteristic diagram of the half mirror 3. The half mirror 3 is obtained by coating a surface of a flat glass or a flat plastic with a metal thin film or a dielectric multilayer thin film. For example, as shown in FIG. 2, incident light (S) incident at 45 degrees is 1: 1. The light is equally divided into reflected light (R) and transmitted light (T) at a ratio. The metal thin film half mirror 3 has a characteristic that there is little light absorption loss due to the film, but there is little dependency on wavelength and incident angle. The dielectric multilayer thin film half mirror 3 has a feature that there is almost no absorption loss of light due to the film, but there is much dependency on wavelength and incident angle. In the first embodiment, since the image light includes all wavelengths of visible light, the metal thin film half mirror 3 having little wavelength dependency is used.
[0014]
In the first embodiment, such characteristics of light reflection and transmission by the half mirror 3 are used. That is, the image light projected downward from the display unit 1 installed horizontally on the ceiling 2 in the passenger compartment enters the surface of the half mirror 3 at an incident angle of about 45 degrees , and the half mirror 3 as described above. Therefore, half of the image light is reflected rearward of the vehicle and the other half is transmitted downward. Similarly, the background light from the front of the vehicle is incident on the surface of the half mirror 3 at an incident angle of about 45 degrees , half of the background light is transmitted rearward of the vehicle, and the other half is reflected downward. Therefore, the occupant 5 seated in the rear seat 4 can visually recognize the virtual image of the image of the display unit 1 superimposed on the background in front of the vehicle through the half mirror 3.
[0015]
FIG. 3 is a cross-sectional view of the moving object rear seat video display device according to the first embodiment, and shows the position of the virtual image displayed on the half mirror 3. As shown in FIG. 3, the occupant 5 seated on the rear seat 4 visually recognizes the virtual image at a position separated from the half mirror 3 by a distance b equal to the distance a from the display unit 1 to the half mirror 3. Become.
[0016]
FIG. 4 is a block diagram of video signal processing of the moving body rear seat video display apparatus according to the first embodiment. Since the virtual image projected by the optical imaging relationship as described above is a horizontally reversed image displayed on the display unit 1, as shown in FIG. It is necessary to display on the display unit 1 an image that has been horizontally reversed by the processing circuit 10.
[0017]
FIG. 5 is a block diagram of the video left / right inversion processing circuit 10. As shown in FIG. 5, the video left / right inversion processing circuit 10 includes a sync separation circuit 11 that separates a video signal and a sync signal, an A / D conversion circuit 12 that converts an analog video signal into a digital video signal, and a digital video signal. An input selector switch 13 for switching the input destination, two line memories 14 for storing digital video data for one line (hereinafter referred to as one line data) included in the digital video signal, storage of one line data in the line memory 14 and Read / write control circuit 15 for controlling reverse reading, output changeover switch 16 for switching the output source of one line data, D / A conversion circuit 17 for converting a digital video signal into an analog video signal, and synthesizing the video signal and the synchronization signal The synthesizing and synthesizing circuit 18 is configured.
[0018]
When an analog video signal is input to the video left / right inversion processing circuit 10, first, the synchronization separation circuit 11 separates the synchronization signal included in the video signal. The separated synchronization signal is input to the input changeover switch 13, the read / write control circuit 15, the output changeover switch 16, and the synchronization synthesis circuit 18. The analog video signal separated by the synchronization separation circuit 11 is converted into a digital video signal by the A / D conversion circuit 12. The first line data included in the converted digital video signal is stored in the first line memory 14 connected by the input selector switch 13. When the storage of the first one-line data is completed, the input selector switch 13 is switched based on the separated synchronization signal, and the second one-line data is stored in the other second line memory 14. The above process is repeated for each line data, and a plurality of one line data constituting the video is alternately stored in the first or second line memory 14.
[0019]
While the second one-line data is being stored in the second line memory 14, the read / write control circuit 15 uses the first one-line data previously stored in the first line memory 14. Control is performed so that addresses are read out in the reverse order of storage. The first one-line data read out in the reverse order is input to the D / A conversion circuit 17 connected by the output changeover switch 16 switched based on the synchronization signal, and converted again into the analog video signal. The converted analog video signal is input to the synthesizing and synthesizing circuit 18, and the synchronizing signal separated here is synthesized again and output as a normal video signal. In this way, the series of processes described above is performed for each line data of the input video signal, and this is repeated for all the video signals, so that the horizontally reversed video is displayed on the display unit 1. become.
[0020]
As described above, the video displayed on the display unit 1 is a video that is horizontally reversed by the video left / right reversing processing circuit 10, and thus the virtual image that is reflected by the reflection at the half mirror 3 is normal that is not horizontally reversed. It becomes a video and is visually recognized by the occupant 5 seated on the rear seat 4.
[0021]
As described above, according to the first embodiment, it is possible to display an image on the back seat 4 of the mobile body, and at the same time, it is possible to easily check the background outside the mobile body and appreciate the scenery. A video display device for the use is obtained. In particular, the driver 8 of the vehicle seated in the front seat 7 can easily confirm the rear by the rearview mirror 9 or direct view while the image is being displayed, and the occupant 5 seated in the rear seat 4 is viewing the display image. At the same time, the background in front of the vehicle can be visually recognized. In addition, since the video whose left and right are reversed by the video left / right reversing processing circuit 10 is projected, a normal image without left / right reversal is obtained as the image projected by the reflection by the half mirror 3. Further, since the number of reflections is only one, there is little light loss due to reflection, and a bright image can be obtained.
[0022]
In Embodiment 1, the half mirror 3 equally divides incident light (S) incident at about 45 degrees into reflected light (R) and transmitted light (T) at a ratio of 1: 1. The incident light may be divided at other spectral ratios by changing the specifications of the thin film to be coated on the surface. In this way, by changing the spectral ratio of the half mirror 3, the degree of visual recognition of the image and the background can be adjusted. Further, the same adjustment can be performed by adjusting the light intensity of the backlight of the LCD constituting the display unit 1 which is the image display means.
[0023]
Embodiment 2. FIG.
FIG. 6 is a configuration diagram of the moving body rear seat video display apparatus according to the second embodiment of the present invention. Here, an example in which a virtual image without left-right reversal is displayed without using the video left-right reversal processing circuit 10 is shown.
[0024]
In FIG. 6, a display unit 1 as an image display means composed of an LCD or the like for displaying an image is disposed on the rear side surface of the center console 19 located at the center of the seat floor in the vehicle compartment, with the display surface facing upward. It is mounted almost horizontally. The support portion of the display unit 1 can be bent, and can be stored by being folded parallel to the rear side surface of the center console 19 when not used. Further, above the display unit 1, a half mirror 3 as a reflection / transmission means that transmits or reflects an image displayed on the display unit 1 and transmits the background, the surface of the half mirror 3 with respect to the display surface of the display unit 1. It is installed so as to hang from the ceiling part 2 in the passenger compartment so as to form an angle of about 45 degrees . Further, in the center of the ceiling portion 2, a total reflection mirror 20 as a video left / right reversing unit that totally reflects the image displayed on the display unit 1 is arranged so that the reflection surface thereof faces the display surface of the display unit 1 in parallel. Is installed.
[0025]
Next, the operation will be described.
The image displayed on the display unit 1 is transmitted through the half mirror 3 and totally reflected by the total reflection mirror 20 so that the left and right are reversed. Furthermore, the left and right are reversed again by being reflected by the half mirror 3 in the direction of about 90 degrees . In this way, the occupant 5 seated in the rear seat 4 sees through the half mirror 3 a virtual image having the same left-right relationship as the image displayed on the display unit 1. At the same time, the background in front of the vehicle passing through the windshield 6 and passing through the half mirror 3 is also visually recognized. In addition, the driver 8 of the vehicle seated on the front seat 7 sees the background behind the vehicle that is transmitted through the half mirror 3 and reflected by the rear mirror 9 from the rear.
[0026]
FIG. 7 is a cross-sectional view of the moving body rear seat video display device according to the second embodiment, and shows the positional relationship of virtual images projected in the configuration shown in FIG. As shown in FIG. 7, the occupant 5 seated in the rear seat 4 is the sum of the distance a from the display unit 1 to the total reflection mirror 20 and the distance b from the total reflection mirror 20 to the half mirror 3 (a + b ), The virtual image is visually recognized at a position away from the half mirror 3 forward.
[0027]
As described above, according to the second embodiment, since the total reflection mirror 20 that optically totally reflects the image is used as the image left / right reversing means, the image left / right reversal as shown in the first embodiment is used. The reversal processing circuit 10 does not need to reverse the left and right images, and a cheaper moving body rear seat image display device can be obtained.
[0028]
In addition, the arrangement form of the display unit 1 that is a video display unit, the half mirror 3 that is a reflection / transmission unit, and the total reflection mirror 20 that is a video left-right reversing unit shown in the first embodiment or the second embodiment is an example. The present invention is not limited to these. That is, it is only necessary to have the same video display function even in other arrangement forms.
[0029]
Further, in the first or second embodiment, as the image enlarging means, a lens is provided in the optical path of the image, or a concave magnifying glass is used as a reflecting mirror such as the half mirror 3 or the total reflection mirror 20, thereby displaying the displayed image. May be enlarged (not shown). By using such an image enlarging means, the display image can be enlarged, and the occupant 5 of the rear seat 4 can appreciate a powerful large screen image. Further, in this case, since the display unit 1 as the video display means can be reduced in size, it is possible to realize downsizing and cost reduction as a device, and a space-saving and inexpensive video display device for a mobile rear seat. Is obtained.
[0030]
Further, as the video displayed in the first or second embodiment, in addition to the television and video images, image information such as maps and routes from the car navigation device, VICS (Vehicle Information and Communication System, road Traffic information communication system) It is also possible to display traffic information such as traffic congestion information from the receiver, and vehicle information such as vehicle speed and engine speed from the vehicle electronic control unit. An in-vehicle information display device capable of displaying various information on the seat is obtained.
[0031]
【The invention's effect】
Since the present invention is configured as described above, the following effects are obtained.
[0032]
According to the video display device for a vehicle rear seat according to the present invention, the image is placed and the image horizontally inverting means for inverting the left and right images by the video signal processing, the display surface near the center of the ceiling portion of the vehicle compartment in the lower a video display means for displaying an image which is horizontally inverted by the left and right reversal means and is placed under the Film image display means for reflecting the image. Thus a reflective transmission means for transmitting the background, the rear of the vehicle There is an effect that it is possible to display an image on the seat, and at the same time, it is possible to obtain an excellent vehicle rear seat image display device that can easily check the background outside the vehicle and view the scenery. In particular, even during video display, there is an effect that it is possible to easily confirm the back background from the front seat by the rearview mirror or direct view or the front background from the rear seat. Further, the image displayed by reflection by the reflection / transmission means can be obtained as a normal image without left-right reversal, and a bright image with little light loss due to reflection can be obtained.
[0034]
Further, according to the video display device for a vehicle rear seat according to the present invention, an image display means for displaying an image is placed in the top display surface near the seat floor center of the vehicle interior, it is arranged above the image display unit Left-right reversal of the image comprising reflection / transmission means that transmits the image output from the image display means and a total reflection mirror that is installed near the center of the ceiling in the vehicle interior and optically totally reflects the image transmitted by the reflection / transmission means The image output from the video left / right reversing means is reflected and the background is transmitted by the reflection / transmission means , so that an inexpensive vehicle rear seat video display device can be obtained. .
[0035]
Also, according to the vehicle rear seat video display device according to the present invention, since the video enlargement means for enlarging the video is provided, the display video can be enlarged, and the large screen video that is powerful at the rear seat It is possible to appreciate. In addition, since the video display means can be reduced in size, it is possible to reduce the size and cost of the device, and to obtain a space-saving and inexpensive vehicle rear seat video display device.
[Brief description of the drawings]
FIG. 1 is a configuration diagram of a moving body rear seat video display device according to a first embodiment of the present invention.
FIG. 2 is a characteristic diagram of a half mirror of the moving body rear seat video display device according to the first embodiment of the present invention.
FIG. 3 is a cross-sectional view of the moving body rear seat video display device according to the first embodiment of the present invention.
FIG. 4 is a block diagram of video signal processing of the moving body rear seat video display device according to the first embodiment of the present invention.
FIG. 5 is a block diagram of a video left / right reversing processing circuit of the moving body rear seat video display device according to the first embodiment of the present invention.
FIG. 6 is a configuration diagram of a moving body rear seat video display device according to a second embodiment of the present invention.
FIG. 7 is a cross-sectional view of a moving body rear seat video display device according to a second embodiment of the present invention.
FIG. 8 is a block diagram showing a conventional moving body rear seat video display device.
FIG. 9 is a cross-sectional view showing a conventional moving body rear seat video display device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Display part, 2 ceiling parts, 3 half mirrors, 4 back seats, 5 passengers, 6 windshields, 7 front seats, 8 drivers, 9 room mirrors, 10 video left-right inversion processing circuit 10, 11 synchronization separation circuit, 12 A / D conversion circuit, 13 input changeover switch, 14 line memory, 15 read / write control circuit, 16 output changeover switch, 17 D / A conversion circuit, 18 synchronous synthesis circuit, 19 center console, 20 total reflection mirror, 101 display unit , 102 Rear seat, 103 Crew, 104 Ceiling, 105 Open button, 106 Open / close detection sensor, 107 Front seat, 108 Driver, 109 Rearview mirror, 110 Windshield

Claims (3)

Video left / right reversing means for reversing the left / right of the video in the video signal processing, and video display for displaying the video reversed left and right by the video left / right reversing means installed near the center of the ceiling in the vehicle compartment means and, before Symbol while reflecting the installed the image below the image display means, the image display device for a vehicle rear seat, characterized in that a reflecting transmission means for transmitting the background. Video display means installed near the center of the seat floor in the vehicle compartment with the display surface facing up and displaying video ; Reflective transmission means installed above the video display means and transmitting video output from the video display means; And a video left / right reversing means comprising a total reflection mirror optically and totally reflecting the image transmitted by the reflection / transmission means and installed near the center of the ceiling of the vehicle interior, and the image left / right reversal by the reflection / transmission means An image display device for a rear seat of a vehicle, wherein an image output from the means is reflected and a background is transmitted . The video display device for a vehicle rear seat according to claim 1, further comprising video enlargement means for enlarging the video.

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