close

Вход

Забыли?

вход по аккаунту

JP2004056262

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JP2004056262
An acoustic system capable of setting an optimal sound field even when a center speaker is
disposed on the rear side of a screen. SOLUTION: When the center speaker 4 is arranged on the
back side of the screen 1, the high frequency component sound of the center speaker 4
attenuated by the screen 1 is corrected sound from the correction speaker 5 arranged on the
front side of the screen 1. It is made to output as. As a result, even when the center speaker 4 is
disposed on the back side of the screen 1, proper audio output of the center speaker 4 can be
obtained at the viewing position where the user views. [Selected figure] Figure 1
Sound system
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an
acoustic system suitable for a projector that displays an image using, for example, a screen. 2.
Description of the Related Art In recent years, a projector that displays a large screen image
using a screen has been widely spread in general homes and the like. In such a projector, a multichannel audio system using a plurality of speakers such as a 5.1 channel surround system is
provided as an audio system. [0003] FIG. 8 is a view showing an arrangement example of a
fluorocarbon speaker in a conventional acoustic system. The sound system shown in FIG. 8 is
provided with a left speaker 101, a right speaker 102, and a center speaker 103 as front
speakers. In this case, the left speaker 101 is disposed on the front left side of the screen 100,
and the right speaker 102 is disposed on the front right side. Further, a center speaker 103 is
disposed substantially at the center of the screen 100. By the way, in the case where the front
speakers are arranged as described above, when the center speaker 103 is arranged on the front
side of the screen 100, ie, on the front side of the screen 100, the user can When looking at the
screen 100, the center speaker 103 gets in the way. For this reason, the center speaker 103 is
usually disposed below or above the screen 100, as indicated by a broken line. However, if the
04-05-2019
1
center speaker 103 is disposed at the lower side or the upper side of the screen 100, the sound
image localization position by the center speaker 103 is inevitably deviated from the proper
arrangement position. Can not do it. Therefore, for example, it is conceivable to dispose the
center speaker 103 on the back side of the screen 100 so that the center speaker 103 can not be
seen from the front side of the screen 100. However, in this case, the high-frequency component
of the sound output from the center speaker 103, for example, a signal component of 2 kHz or
more is attenuated due to the transmission acoustic characteristic of the screen 100, and as a
result, it is optimum Sound field setting could not be done. In order to prevent the attenuation of
high frequency components due to the screen 100 as described above, there are screens in which
fine holes are made in the screen 100 to improve the acoustic characteristics. From the
relationship, it is difficult to improve the acoustic characteristics by enlarging the shape of the
holes formed in the screen, and therefore it was not possible to sufficiently prevent the
attenuation of the high frequency component.
Therefore, the present invention has been made in view of such a point, and an appropriate
sound field is provided even when the center speaker is disposed on the back side of the screen
so as not to disturb the image displayed on the screen. It is an object of the present invention to
provide an acoustic system that can be set. SUMMARY OF THE INVENTION In order to achieve
the above object, the acoustic system of the present invention comprises a main speaker
disposed on the back side of the screen and a front side of the screen And an auxiliary speaker
for outputting a correction voice for correcting a required band component of the output voice
reaching the sound reception position through the light. According to the present invention,
when the main speaker (center speaker) is arranged on the back side of the screen, the sound of
the required band component of the main speaker attenuated by the screen is arranged on the
front side of the screen By outputting the correction sound from the speaker (correction
speaker), even when the main speaker is disposed on the back side of the screen, an appropriate
sound output of the main speaker can be obtained at a predetermined sound receiving point.
BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be
described below. In the present embodiment, an audio system provided in an AV system such as
a projector using a screen will be described as an example. FIG. 1 is a view showing an
arrangement example of front speakers in the acoustic system of the present embodiment. In
addition, this FIG. 1 is the figure which looked at the sound system of this Embodiment from the
upper surface side. As shown in FIG. 1, in the sound system according to the present
embodiment, a screen 1 for displaying an image projected from a projector main body 6, a left
speaker 2, a right speaker 3, and a center that is a main speaker It is comprised by four speakers
called the speaker 4 and the correction ¦ amendment speaker 5 which is a secondary speaker.
The left speaker 2 is disposed on the left side of the screen 1. Also, the sound emission surface is
directed to the sound receiving position L. The sound of the left channel (Lch) is output from
such a left speaker 2. In this case, the direct sound of the left speaker 2 reaches the user at the
sound reception position L. The right speaker 3 is disposed on the right side of the screen 1. The
04-05-2019
2
sound emitting surface of the right speaker 3 is also directed to the sound receiving position L as
described above. The sound of the right channel (Rch) is output from such a right speaker 3.
In this case, the direct sound of the right speaker 3 reaches the user at the sound reception
position L. The center speaker 4 is disposed on the back side of the screen 1. The sound emitting
surface of the center speaker 4 in this case is also directed to the sound receiving position L.
Then, the sound of the center channel (Cch) is output from such a center speaker 4. In this case,
since the center speaker 4 is disposed on the rear side of the screen 1, the sound of the center
channel output from the center speaker 4 (hereinafter referred to as center sound ) passes
through the screen 1. In this case, high-frequency components of, for example, 2 kHz or more are
attenuated according to the acoustic characteristics of the screen 1. Therefore, from the front of
the screen 1, a center voice whose high frequency component is attenuated is output, and this
center voice reaches the sound receiving position L user. The correction speaker 5 is disposed on
the front side of the screen 1. Further, the correction speaker 5 is structured to have sharp
directivity so as to emit a sound wave only in a specific direction (for example, an axial direction
orthogonal to the sound emitting surface). The sound emission surface of the correction speaker
5 is directed to the required position of the screen 1 such that the reflected sound reflected by
the screen 1 reaches a predetermined sound receiving position L when the sound is emitted from
the correction speaker 5. There is. The correction speaker 5 outputs correction sound for
correcting the high-frequency component of the center sound from the center speaker 4
attenuated by the screen 1. In this case, since the correction speaker 5 has sharp directional
characteristics and the sound emission surface of the correction speaker 5 is directed to the
screen 1, the correction voice output from the correction speaker 5 is a screen 1. It will be
reflected to reach the receiving position L. Therefore, at the sound receiving position L, the high
frequency component of the center sound from the center speaker 4 is corrected by the
correction voice from the correction speaker 5, and an appropriate center sound can be obtained
at the sound receiving position L. Although it is sufficient to set a required band according to the
high-frequency component of the center sound attenuated by the screen 1 as the band of the
correction sound output from the correction speaker 5, the correction output from the correction
speaker 5 is Since the voice needs to have sharp directional characteristics, it is preferable to set,
for example, at 5 kHz or higher from the viewpoint of the directional characteristics.
Further, the installation positions of the left speaker 2, the right speaker 3, and the center
speaker 4 in the sound system of the present embodiment are set by, for example, setting the
sound field based on the sound receiving position L of the user. It is decided. Also, if the
installation position of the correction speaker 5 is such a position that the correction voice from
the correction speaker 5 is reflected by the screen 1 and reaches the predetermined sound
receiving position L, for example, It is possible to install in the ceiling etc. of the room in which
the sound system of an embodiment is set. In addition, for example, when the sound field is set so
04-05-2019
3
that the user's viewing position is located at approximately the center of the screen 1, the
arrangement position of the center speaker 4 is approximately at the center position of the
screen 1. In this case, the arrangement position of the center speaker 4 substantially coincides
with the projector main body 6. In this case, the path of the correction sound output from the
correction speaker 5 and the optical axis of the image output from the projector main body 6
also substantially coincide with each other. Therefore, in this case, since the correction speaker 5
can be integrated with the projector main body 6, there is an advantage that the user does not
have to set the correction speaker 5 in this case. FIG. 2 is a diagram showing the relationship
between the center speaker and the correction speaker. As shown in FIG. 2, the sound wave P
<b> 1 output from the center speaker 4 passes through the screen 1 and reaches the user of the
sound receiving position L. On the other hand, the sound wave P2 output from the correction
speaker 5 is reflected by the screen 1, and the reflected sound wave P2 reaches the user of the
sound receiving position L. Thereby, as described above, at the sound receiving position L, the
high frequency component of the center sound from the center speaker 4 is corrected by the
correction sound of the correction speaker 5, and at the sound receiving position L, the center
sound is proper. Will be obtained. Further, in this case, since the distance from the center
speaker 4 to the screen 1 and the distance from the correction speaker 5 to the screen 1 are
different, the center sound of the center speaker 4 and the correction sound of the correction
speaker 5 are at the same timing. When output, at the sound receiving position L, the correction
voice of the correction speaker 5 will be heard delayed. Therefore, in the present embodiment, as
described later, the sound output from the center speaker 4 is delayed according to the distance
difference between the distance from the center speaker 4 to the screen 1 and the distance from
the correction speaker 5 to the screen 1 Thus, at the sound receiving position L, the timing of the
center sound of the center speaker 4 and the timing of the correction sound of the correction
speaker 5 are made to coincide with each other.
In this case, as described above, since the correction speaker 5 has such a sharp directivity that
emits a sound wave only in the direction of the screen 1, it is shown in FIG. Thus, for example,
even if the correction speaker 5 is disposed behind the user at the sound reception position L,
the direct sound of the correction speaker 5 hardly reaches the user. FIG. 3 is a block diagram
showing an internal configuration of the sound system shown in FIG. As shown in FIG. 3, the
audio signal of the right channel (Rch) to be input is amplified by the amplifier 11 through the
delay circuit 17 and input to the right speaker 3. Then, the right speaker 3 outputs an audible
sound. The audio signal of the left channel (Lch) to be input is amplified by the amplifier 12
through the delay circuit 18 and input to the left speaker 2. Then, the left speaker 2 outputs an
audible sound. On the other hand, the audio signal of the center channel (Cch) is delayed by the
delay circuit 13, then amplified by the amplifier 14 and input to the center speaker 4. As
described above, the delay circuit 13 inputs an audio signal to the center speaker 4 for a time
corresponding to the distance difference (path difference) between the distance from the center
speaker 4 to the screen 1 and the distance from the correction speaker 5 to the screen 1. Is to
04-05-2019
4
delay. The audio signal of the center channel (Cch) is also input to the high pass filter 15, and the
audio signal passing through the high pass filter (HPF) 15 is amplified by the amplifier 16 and
input to the correction speaker 5. . The HPF 15 extracts a predetermined high frequency
component from the audio signal of the center channel (Cch) and inputs it to the correction
speaker 5. In this case, the signal band extracted from the audio signal of the center channel in
the HPF 15 is determined in accordance with the transmission acoustic characteristic of the
screen 1. The delays by the delay circuits 17 and 18 are adjusted so that the audio signals of the
right channel (Rch), the left channel (Lch) and the center channel (Cch) arrive at the sound
receiving position L substantially simultaneously. Although it is desirable, these delay circuits 17
and 18 can be omitted depending on the positional relationship between the speakers and the
sound receiving position L. Further, the internal configuration of the sound system shown in FIG.
3 is merely an example, and can of course be realized by another configuration.
For example, in the example shown in FIG. 3, the correction signal for correcting the center
sound output from the center speaker 4 is such that the HPF 15 extracts it from the sound signal
of the center channel, but may be realized with other configurations. it can. For example, an
equalizer is provided on the input signal line of the center speaker 4, and among the signals
input to the center speaker 4, a signal of a predetermined frequency band is corrected by the
equalizer. The signal above the predetermined frequency band may be corrected by the
correction speaker 5. Specifically, in the case where an audio signal of, for example, 2 kHz or
more is attenuated by an attenuation curve of 6 db / octave according to the transmission
acoustic characteristic of the screen 1, for example, 10 kHz or less of the signals input to the
center speaker 4 Signal is corrected by an equalizer or the like. Then, it is also possible to correct
the signal of 10 kHz or more which can not be corrected by the equalizer with the correction
speaker 5. Alternatively, when the reproduction frequency band of the correction speaker 5 is
limited to the high tone range, the HPF 15 can be deleted. Here, FIG. 4 shows a structural
example of a sharp directional speaker used as the above-mentioned correction speaker. FIG. 4A
is a view showing a structural example of a horn speaker having a sharp directivity. When
constructing the horn speaker 21 having a sharp directional characteristic as shown in FIG. 4A,
for example, the length of the flange 22 portion is larger than that of a normal horn speaker
having a wide directional characteristic having a shape as shown by a broken line. shorten.
Further, the spread of the flange 22 is reduced to reduce the opening area of the opening surface
23. As a result, a compact and superdirective horn speaker can be configured. Further, FIG. 4B
shows an array speaker composed of a plurality of speaker units SP as another structural
example of the sharp directional speaker. Such an array speaker 31 changes the amplitude and
phase of the audio signal input to each speaker unit SP, SP according to a certain function after
forming each speaker unit SP, SP. Thus, it is possible to configure a speaker having any
directivity. Therefore, in the present embodiment, the correction speaker 5 may be configured by
the horn speaker 21 or the array speaker 31 described above, and the directivity characteristic of
the correction speaker 5 may be a characteristic as shown in FIG.
04-05-2019
5
That is, almost no output sound pressure can be obtained in the sound receiving direction in
which the user is located, for example, in the left-right direction (90 °, -90 °) with respect to
the axial direction (0 °). It may be a sharp directional speaker having a The correction speaker 5
can also be configured by an ultrasonic speaker having directivity. Although illustration and
detailed description of the ultrasonic speaker is omitted, the ultrasonic speaker is also called a socalled parametric speaker, and emits two types of ultrasonic waves having different frequencies,
so that the non-linearity of air as a propagation medium causes these. An audible sound is output
at a reflection surface on which the ultrasonic wave is reflected. According to the sound system
of the present embodiment, when the center speaker 4 is disposed on the back side of the screen
1, the sound of the high frequency component of the center speaker 4 attenuated by the screen 1
can be the screen 1 It outputs as a correction ¦ amendment audio ¦ voice from the correction ¦
amendment speaker 5 arrange ¦ positioned at the front side of. Thereby, even when the center
speaker 4 is disposed on the back side of the screen 1, it is possible to output an appropriate
sound of the center speaker 4 at the viewing position where the user views. As described above,
in the sound system of the present embodiment, the center speaker 4 is disposed on the back
side of the screen 1. Then, by arranging the center speaker 4 on the back side of the screen 1, a
correction speaker 5 that outputs a correction sound for correcting the high frequency
component of the center sound attenuated in the screen 1 by the transmission acoustic
characteristic of the screen 1. Was placed on the front side of the screen 1. Thereby, even when
the center speaker 4 is disposed on the back side of the screen 1, at the sound receiving position
L, the center sound of the center speaker 4 can be corrected by the correction sound of the
correction speaker 5. In L, a proper center voice can be obtained. Further, according to the sound
system of the present embodiment, the center speaker can be disposed other than the lower side
or the upper side of the screen, and the degree of freedom of the installation position of the
center speaker 4 can be expanded. Further, in this case, since the center sound which is
attenuated according to the transmission acoustic characteristic of the screen 1 can be effectively
corrected, an excellent reproduction sound can be realized. FIG. 6 is a view showing an example
of the arrangement of speakers in an acoustic system according to another embodiment.
In addition, this FIG. 6 is the figure which looked at the arrangement position of the speaker from
the upper surface side. Further, in FIG. 6, the same parts as those in FIG. In the sound system
shown in FIG. 6, the left and right speakers 2 and 3 disposed on both sides of the screen 1 in FIG.
1 are disposed on the back side of the screen 1. Therefore, in this case, in addition to the center
sound output from the center speaker 4, the left and right sounds output from the left and right
speakers 2 and 3 also pass through the screen 1 according to the transmission acoustic
characteristics of the screen 1. High frequency components are attenuated. For this reason, in the
sound system shown in FIG. 6, in addition to the correction speakers 5 for correcting the high
frequency band of the center sound of the center speaker 4 described above on the front side of
04-05-2019
6
the screen 1, The correction speakers 41 and 42 are provided as second sub-speakers that
respectively correct the high frequency band of the left and right voices. In this case, these
correction speakers 41 and 42 have a sharp directivity such that sound waves are emitted only in
a specific direction (for example, an axial direction orthogonal to the sound emitting surface),
similarly to the correction speaker 5. The sound emitting surfaces of the correction speakers 41
and 42 are directed from the correction speakers 41 and 42 to the position of the screen 1
where the reflected sound reflected by the screen 1 reaches the sound receiving position L.
Therefore, the correction sound radiated from such correction speakers 41 and 42 is such that
the correction speaker 5 has a sharp directional pattern, and the sound emitting surface of the
correction speakers 41 and 42 is directed to the screen 1. Therefore, the correction voices output
from such correction speakers 41 and 42 are reflected by the screen 1 and reach the user at the
reception position L. As a result, at the sound receiving position L, the high frequency
components of the sound from the center speaker 4 and the left and right speakers 2 and 3 are
corrected by the correction voices of the correction speakers 5, 41 and 42, and appropriate
sound is received at the sound receiving position L. You will be able to get it. FIG. 7 is a block
diagram showing the internal configuration of the acoustic system shown in FIG. Also in this
case, the same parts as those in FIG. In this case, since the right speaker 3 is disposed on the
back side of the screen 1, the input right channel (Rch) audio signal is delayed by the delay
circuit 43 and input to the amplifier 11. Similarly, the audio signal of the left channel (Cch) to be
input is delayed by the delay circuit 44 and input to the amplifier 12.
In this case, the HPF 45 extracts high frequency components from the audio signal of the right
channel (Rch) to be input to the correction speaker 41, and then the audio signal amplified by the
amplifier 46 is input. Similarly, the HPF 47 extracts high frequency components from the audio
signal of the left channel (Lch) to be input to the correction speaker 42, and then the audio signal
amplified by the amplifier 48 is input. Also in the case where the sound system is configured as
described above, it is possible to obtain an appropriate sound at the sound receiving position L. If
such an acoustic system is applied to, for example, a projector using a large screen where the left
and right speakers 2, 3 can not be arranged on the side of the screen 1, the degree of freedom of
the arrangement position of the left and right speakers 2, 3 is increased. There is an advantage to
say. Also in this case, it is possible to effectively correct the left and right and center sounds that
are attenuated according to the transmission acoustic characteristics of the screen 1, so that
excellent reproduction sound can be realized. In the present embodiment, the sound system
provided in an AV system such as a projector using a screen has been described as an example,
but this is merely an example, and the sound system of the present invention is a screen The
present invention can be applied to any device as long as it uses a device. Further, in the present
embodiment, the case where the left and right speakers and the center speaker are provided as
the front speakers has been described as an example, but the sound system of the present
invention includes at least the center speaker as the front speakers. Can be realized. As described
above, according to the sound system of the present invention, when the center speaker, which is
04-05-2019
7
the main speaker, is disposed on the back side of the screen, the high frequency region of the
center speaker is attenuated by the screen. Since the component sound is output as the
correction sound from the correction speaker which is the sub-speaker disposed on the front side
of the screen, even when the center speaker is disposed on the back side of the screen, the center
is located at the viewing position where the user views Proper audio output of the speaker can be
obtained. In this way, even if the center speaker is installed on the back side of the screen, it is
possible to obtain an appropriate center sound, so it is possible to expand the freedom of the
installation position of the center speaker. This makes it possible to provide an acoustic system
capable of performing appropriate sound field setting.
For example, if the present invention is applied to an AV system using a screen such as a
projector, the acoustic characteristics can be effectively compensated, so that excellent
reproduced sound corresponding to a reproduced image can be output. BRIEF DESCRIPTION OF
THE DRAWINGS FIG. 1 is a view showing an arrangement example of speakers in an acoustic
system as an embodiment of the present invention. FIG. 2 is a diagram showing sound wave
paths radiated from a center speaker and a correction speaker. 3 is a block diagram showing an
internal configuration of the acoustic system shown in FIG. FIG. 4 is a view showing an example
of the structure of a sharp directional speaker. FIG. 5 is a diagram showing a polar pattern of a
sharp pointing speaker. FIG. 6 is a view showing an arrangement example of speakers in an
acoustic system of another embodiment. 7 is a block diagram showing an internal configuration
of the acoustic system shown in FIG. FIG. 8 is a view showing an example of arrangement of
speakers in a conventional sound system. [Description of the code] 1 screen 2 left speaker 3 right
speaker 4 center speaker 5 41 42 correction speaker 7 projector main body 11 12 14 16 46 48
amplifier 13 43 44 delay circuit 15 45 47 HPF, 21 Horn speaker, 31 array speaker
04-05-2019
8
1/--страниц
Пожаловаться на содержимое документа