This application is a U.S. national phase application of PCT International Application PCT/JP2005/002002.
1. Field of the Invention
The present invention relates to a mobile telephone, personal digital assistant (PDA), game machine, or other information terminal device used in various information communications.
2. Description of the Related Art
A conventional information terminal device will be explained by referring to
In
A conventional information terminal device similar to device 510 is disclosed, for example, in Japanese Patent Publication No. 2003-78601 (unexamined).
However, an information terminal device having such conventional configuration has difficulty reproducing reality and presence by stereophonic acoustics in stereophonic sound reproduction.
A cause of the difficulty is disagreement between video localization of video display unit 560 and audio localization in a vertical direction of audio output units 571, 572. Audio output units 571, 572 are disposed closely to the two corners at opposite ends of a diagonal of video display unit 560. That is, audio output units 571, 572 are disposed symmetrical in a diagonal form with respect to video display unit 560.
At times, the audio localization of audio output units 571, 572 is in the center of a straight line linking the two speakers. The straight line linking the audio output units 571, 572 is nearly parallel to a diagonal of upper case 520. The video localization of video display unit 560 is also in the center of the rectangular screen, and the video localization coincides with the audio localization. However, this coincidence of video localization and audio localization only occurs when the output sound pressure levels from the right and left speakers are equal to each other. In this limited condition, the sound is localized midway between the right and left speakers, and coincides with the video localization of video display unit 560. In reality, however, the speakers are very rarely operated in such condition.
When audio data is reproduced from audio output units 571, 572, the changing of audio signals at every moment always causes output sound pressure level differences between the right and left speakers. When output sound pressure level differences are caused between the right and left speakers, the sound is not localized in the center of the screen, and is deviated toward the speaker of higher sound pressure level. Due to difference in sound pressure levels of the right and left speakers, the sound comes to have a depth, and the audio localization can be moved along with the video localization.
However, when the audio localization moves on the straight line between the right and left speakers due to such change in sound pressure levels, since the straight line linking the right and left speakers is not horizontal, a problem lies in localization in the vertical direction. That is, the audio localization is also moved in the vertical direction by the portion of deviation from the center to either the upper or the lower side. This is sensed because the human audible sense works in both the lateral direction and the vertical direction.
Therefore, for the user of the information terminal device, the video localization of the video display unit and the audio localization of the audio output units do not coincide in the vertical direction. That is, the direction sense to video and the direction sense to audio do not coincide, and strangeness is felt in hearing sensation. As a result, the conventional information terminal can hardly satisfy the reality and presence by stereophonic acoustics in stereophonic reproduction.
The information terminal device of the invention comprises a main body case, a rectangular video display unit provided on the front side of the main body case, and a plurality of audio output units disposed at a specified angle to the video display unit. The audio output units are formed in any one of a rectangular, elliptical, or track shape. The plurality of audio output units are disposed symmetrically about the center line of the video display unit, and a longer side of the outer shape of each audio output unit is disposed closely to either a longer side or a shorter side of the video display unit.
In this configuration, the information terminal device of the invention reproduces a favorable reality and presence by stereophonic acoustics in stereophonic reproduction. That is, since the audio output units are disposed symmetrically about the center line of the video display unit, the audio localization in vertical direction of the audio output units coincides with the video localization in vertical direction of the video display unit. As a result, the invention satisfies the reality and presence by stereophonic acoustics in stereophonic reproduction.
Preferred embodiments of the invention are specifically described below with reference to the drawings.
Recently, in the market of small information terminal devices such as mobile telephones, which are not limited to information transmission only, higher video and audio quality have been demanded. Especially in the audio quality, as music reception and distribution are sophisticated, there is a strong desire for upgrading stereophonic reproduction for enjoying the music with an advanced reality. The information terminal device of the first preferred embodiment is devised to meet such need, and has the configuration shown in
In
The outer shape of audio output units 81, 82 is formed like a track. The longer side of the track shape of audio output unit 81 is disposed closely to one longer side of the rectangular shape of video display unit 60. The longer side of the track shape of audio output unit 82 is disposed closely to the other longer side of the rectangular shape of video display unit 60. The longer sides of the rectangular shape of video display unit 60 are opposite to each other. Thus, audio output unit 81 and audio output unit 82 are disposed symmetrically about center line 61 of video display unit 60. That is, audio output unit 81 and audio output unit 82 are disposed at both of the mutually opposing longer sides of video display unit 60, respectively.
Speakers used as audio output unit 81 and audio output unit 82 are not limited to a track shape, but may be freely selected from the rectangular, elliptical and track shape.
In the case of rectangular audio output units, the audio output units are disposed symmetrically with respect to center line 61 of video display unit 60, and a longer side of the outer shape of each audio output unit is disposed closely to one of the mutually opposing longer sides of video display unit 60.
In the case of elliptical audio output units, the audio output units are disposed symmetrically with respect to center line 61 of video display unit 60, and a longer side of the outer shape of each audio output unit is disposed closely to one of the mutually opposing longer sides of video display unit 60.
In the case of track shape or elliptical audio output units 81, 82, the ratio of the length of a longer side to the length of a shorter side of the outer shape is 2.5 or more, and slim speakers of large aspect ratio are used. In the case of rectangular audio output units 81, 82, the ratio of the length of a longer side to the length of a shorter side of the outer shape is 2.5 or more, and slim speakers of large aspect ratio are used.
In this configuration, by using slim speakers as audio output units 81, 82, information terminal device 10 has a wider screen, and video display unit 60 can be provided in a limited space. As a result, information terminal device 10 is reduced in size.
According to this configuration, in the information terminal device of the first preferred embodiment, sounds produced from audio output units 81, 82 in stereophonic reproduction correspond to the video image displayed from video display unit 60, and reality and presence are reproduced by stereophonic acoustics. That is, the human hearing sense, like the visual sense, works in both the lateral direction and the vertical direction. Hence, for realistic stereophonic reproduction of sound corresponding to image, it is required that the video localization of video display unit 60 and the audio localization of audio output units 81, 82 coincide for the user of information terminal device 10.
In the information terminal device of the first preferred embodiment, audio output units 81, 82 are disposed symmetrically about center line 61 in the longitudinal direction of video display unit 60. Accordingly, the straight line linking audio output unit 81 and audio output unit 82 is horizontal. Therefore, the audio localization of audio output units 81, 82 is in the center of the straight line linking these two speakers when the output sound pressure levels from the two speakers are equal to each other. The video localization of video display unit 60 is also in the center of the rectangular screen. As a result, the video localization and the audio localization coincide with each other.
Thus, by coincidence between the video localization and the audio localization of information terminal device 10, for example, when the image reproduced by video display unit 60 is a moving picture, a difference is caused in the output sound pressure levels from the right and left speakers depending on the lateral motion of the moving picture, so that the sound emitted by audio output units 81, 82 can be moved in the lateral direction. As a result, a stereophonic sound field can be reproduced without any sense of strangeness.
As mentioned above, in the information terminal device of the first preferred embodiment, at the time of stereophonic reproduction, the audio localization delivered from audio output units 81, 82 corresponds to the video localization displayed by video display unit 60, so that reality and presence by stereophonic acoustics can be reproduced.
Referring next to
In
The layout angle of audio output units 81, 82 corresponding to video display unit 60 is such that the angle A formed between the front side (sound emitting surface) of audio output units 81, 82 and reverse side 110 of video display unit 60 is in a range of 0 degree to 90 degrees, the angle A being 0 degree when the front side (image display surface) of video display unit 60 and the front side (sound emitting surface) of audio output units 81, 82 are disposed on the same plane, and the angle A being 90 degrees when the front side of video display unit 60 and the front side of audio output units 81, 82 are perpendicular. As a result, audio output units 81, 82 are directed outside of upper case 20.
In this configuration, at the time of stereophonic reproduction, sounds produced from audio output units 81, 82 correspond to video images from video display unit 60, and reality and presence by stereophonic acoustics can be enhanced. That is, if the sound is reproduced from information terminal device 10 reduced in size, the sound diffuses as stereophonic sound, and a sound field having a wide service area can be formed, and the sense of presence can be enhanced.
Moreover, by disposing the speakers serving as audio output units 81, 82 at a specified angle, video display unit 60 of maximum size can be disposed in the limited space of upper case 20.
Thus, according to the invention, in spite of the small size, an information terminal device sufficiently satisfying the requirements of reality and presence by stereophonic acoustics at the time of stereophonic reproduction can be presented.
In
The outer shape of audio output units 81, 82 is a track shape. The longer side of the track shape of audio output unit 81 is disposed closely to one shorter side of the rectangular shape of video display unit 60. The longer side of the track shape of audio output unit 82 is disposed closely to the other shorter side of the rectangular shape of video display unit 60. The shorter sides of the rectangular shape of video display unit 60 are opposite to each other. Thus, audio output unit 81 and audio output unit 82 are disposed symmetrically about the center line 62 of video display unit 60. That is, audio output unit 81 and audio output unit 82 are disposed at both of the mutually opposing shorter sides of video display unit 60, respectively.
Speakers used as audio output units 81, 82 are not limited to a track shape, but may be freely selected from the rectangular, elliptical and track shape.
In the case of rectangular audio output units, the audio output units are disposed symmetrically with respect to center line 62 of video display unit 60, and a longer side of the outer shape of each audio output unit is disposed closely to one of the mutually opposing shorter sides of video display unit 60.
In the case of elliptical audio output units, the audio output units are disposed symmetrically with respect to center line 62 of video display unit 60, and a longer side of the outer shape of each audio output unit is disposed closely to one of the mutually opposing shorter sides of video display unit 60.
As shown in
In the first preferred embodiment, the information terminal device is a mobile telephone. But, the features of the first preferred embodiment are not limited to this, and may be further widely applied and extended into a personal digital assistant (PDA), small game machine, car navigation system, portable television, video camera monitor, and other devices.
In
The outer shape of audio output units 81, 82 is formed like a track. The longer side of the track shape of audio output unit 81 is disposed close to one shorter side of the rectangular shape of video display unit 60. The longer side of the track shape of audio output unit 82 is disposed closely to the other shorter side of the rectangular shape of video display unit 60. The shorter sides of the rectangular shape of video display unit 60 are opposite to each other.
Thus, audio output unit 81 and audio output unit 82 are disposed symmetrically about center line 62 of video display unit 60. That is, audio output unit 81 and audio output unit 82 are disposed at the two mutually opposing shorter sides of video display unit 60, respectively.
The second preferred embodiment differs from the first preferred embodiment in that rotation mechanism 120 is provided to rotate upper case 20 with respect to lower case 30, so that video display unit 60 may be used either in a wide profile or in a long profile. In information terminal device 10 of the second preferred embodiment, a rotary hinge is used as rotation mechanism 120.
Audio output units 81 and 82 are of track shape, but a rectangular or an elliptical shape may be also used.
As shown in
In such configuration, the profile of information terminal device 10 can be changed. That is, when carrying information terminal device 10, it is folded as shown in
In this configuration, when information terminal device 10 of the second preferred embodiment reproduces stereophonic sound, sounds produced from audio output units 81, 82 correspond to the video image displayed on video display unit 60, and reality and presence by stereophonic acoustics can be realized. That is, upper case 20 is rotated 90 degrees by rotary hinge 120, and video display unit 60 is shifted from a long profile to a wide profile, so that video display unit 60 has a large aspect ratio is obtained while in use.
Since audio output units 81, 82 are disposed symmetrically about center line 62 in the longitudinal direction of video display unit 60 after rotation, the video image of video display unit 60 of large aspect ratio and the sounds produced from audio output units 81, 82 coincide with each other. As a result, in the invention, at the time of stereophonic reproduction, the sounds produced from audio output units 81, 82 correspond to the video image of large aspect ratio displayed on video display unit 60, so that reality and presence by stereophonic acoustics can be realized.
In the second preferred embodiment, the information terminal device is a mobile telephone. But, the features of the second preferred embodiment are not limited to this, and may be further widely applied and extended into a personal digital assistant (PDA), small game machine, car navigation system, portable television, video camera monitor, and other devices.
The outer shape of audio output units 131, 132, 133, 134 is formed like a track. A longer side of the track shape of each of the audio output units 131, 132 is disposed closely to one longer side of the rectangular shape of video display unit 60. A longer side of the track shape of each of the audio output units 133, 134 is disposed closely to the other longer side of the rectangular shape of video display unit 60. The longer sides of the rectangular shape of video display unit 60 are opposite to each other. Audio output units 131, 132 and audio output units 133, 134 are disposed symmetrically about center line 61 of video display unit 60. That is, audio output units 131, 132 and audio output units 133, 134 are disposed at both sides of the mutually opposite longer sides of video display unit 60, respectively.
Speakers used as audio output units 131, 132, 133, 134 are not limited to a track shape, but may be freely selected from the rectangular, elliptical and track shape.
In the third preferred embodiment shown in
In this configuration, sounds produced from audio output units 131, 132, 133, 134 at the time of stereophonic reproduction correspond to the video image displayed on video display unit 60, and reality and presence by stereophonic acoustics can be realized. That is, if small and slim speakers are used as audio output units, the video localization of video display unit 60 and the audio localization of audio output units 131, 132, 133, 134 coincide with each other.
Therefore, in the information terminal device of the third preferred embodiment, coincidence of video and audio localization can be achieved without using the slim speakers in the shape of the audio output units in the first preferred embodiment shown in
Thus, by achieving coincidence of video localization and audio localization, for example, when the video reproduced by the video display unit is a moving picture, sounds produced by the audio output units can be moved in vertical and lateral directions corresponding to the vertical and lateral motions of the moving picture, so that a satisfactory stereophonic sound field can be reproduced without any sense of strangeness.
The number of speakers used as audio output units is not limited to four, but a plurality of speakers may be disposed symmetrically on both sides of the center line of the upper case.
In
That is, although not shown in the drawings, the longer sides of the outer shape of audio output units 131, 132, 133, 134 may also be disposed closely to each one of the mutually opposite shorter sides of video display unit 60. As a result, when information terminal device 10 is used in the wide profile, video display unit 60 has a wide longitudinal shape as shown in
In this case, video display unit 60 is a liquid crystal panel of the aspect ratio of 3:4 to 9:16, and although the information terminal device is a mobile telephone, a video display unit having an aspect ratio equivalent to that of the video display unit of a television receiver or the like is realized. As a result, together with stereophonic sound, an information terminal device with excellent reality and presence not experienced before can be presented.
Besides, in order for video display unit 60 to be shifted from the long profile to the wide profile, a rotation mechanism (hinge or the like) is provided so as to rotate upper case 20 on lower case 30. In this case, a longer side of the outer shape of each of the audio output units 131, 132, 133, 134 is disposed closely to one of the mutually opposite shorter sides of video display unit 60.
As a result, if small slim speakers are used, information terminal device 10 can be used and carried in different positions. That is, when carrying information terminal device 10, it can be folded. When using video display unit 60 of information terminal device 10, that is, when viewing the visual telephone or moving picture, upper case 20 is rotated by 90 degrees by rotary hinge 120, and video display unit 60 can be changed from the long profile to the wide profile.
Therefore, the invention has the effect of reproducing reality and presence by stereophonic acoustics, at the time of stereophonic reproduction, by correspondence between the sounds from the audio output units and the video image from the video display unit, and the features thereof can be further widely applied and extended into a mobile telephone, personal digital assistant (PDA), small game machine, car navigation system, portable television, video camera monitor, and other information terminal devices.
Number | Date | Country | Kind |
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2004-047271 | Feb 2004 | JP | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/JP2005/002002 | 2/10/2005 | WO | 00 | 7/13/2005 |
Publishing Document | Publishing Date | Country | Kind |
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WO2005/081579 | 9/1/2005 | WO | A |
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Number | Date | Country |
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1-178952 | Jul 1989 | JP |
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2002-111817 | Apr 2002 | JP |
2003-078601 | Mar 2003 | JP |
20-0345703 | Mar 2004 | KR |
Number | Date | Country | |
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20060052128 A1 | Mar 2006 | US |