JPH03214899A - Headphone device - Google Patents

Abstract

PURPOSE:To attain stable binaural reproduction even when a listener moves around freely by sensing a signal for detecting the turning angle information of the head part of listener to a sound source with a pair of signal detectors supporting a supporting means separated from a headphone main body. CONSTITUTION:A reference signal for detecting position transmitted from an ultrasonic speaker 13 of a reference signal source 11 is sensed with a pair of signal setectors 5L and 5R of a headphone device 10 and a detected signal is outputted to an arithmetic device 14. The detectors 5L and 5R are supported by a supporting arms 3L and 3R which is slidably to a hatband 1 and is projection-formed and sense an ultrasonic wave well even when a listener moves and turns his head. The transfer characteristic information of a virtual sound source calculated by the arithmetic circuit 14 is transmitted to an acoustic signal processing circuit 21. The circuit 21 processes an acoustic signal from an acoustic signal supplying source 22 based on the information and transmits to left and right headphone units 2L and 2R.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a headphone device used in an acoustic system that performs pinaural reproduction of acoustic signals. B. Summary of the Invention The present invention is a headphone device used in an acoustic system that performs pinaural reproduction of an acoustic signal, and is used to detect rotation angle information of a listener's head relative to a sound source while the headphone body is attached to the listener's head. A pair of signal detectors that sense signals of The pair of signal detectors always satisfactorily sense the signal for detecting the rotation angle information of the listener's head, thereby stably detecting the rotation angle information of the listener's head.

C. Conventional technology Conventionally, a headphone device that reproduces an acoustic signal using a headphone unit uses a pair of headphone units that are mounted on the listener's head and supported in correspondence near both auricles to reproduce sound. A pinaural system is known as a method for improving the sense of direction of a sound image, the sense of localization outside the head, etc. when reproducing a signal.

The sound reproduction system that uses this pinaural method is
For example, as described in Japanese Patent Publication No. 5:3-283, predetermined signal processing is performed on an acoustic signal reproduced by a headphone device.

Here, the direction of the sound image, the sense of localization outside the head, etc. are determined by the volume difference, time difference, phase difference, etc. between the sounds heard by the left ear and the right ear.

The above-mentioned signal processing refers to, for example, when reproducing sound using a speaker device placed at a distance from the listener, the distance from the sound source, i.e., the speaker device, to the left and right ears of the listener is different and the distance near the listener's head is adjusted. This is signal processing in which an acoustic effect equal to the acoustic effect caused by reflection, diffraction, etc. of the hesodophone occurs in the acoustic output reproduced by the hesodophon device.

Such signal processing can be performed, for example, by supplying left ear and right ear audio signals to the headphone device via a level adjustment circuit, a delay circuit, etc., respectively.

By the way, when sound is reproduced using a speaker device placed at a distance from the listener, the absolute position of the sound image does not change even if the listener moves or rotates the head direction. The relative direction and position of the sound image perceived by the user changes. On the other hand, when a hesodophone device is used to reproduce sound in a pinaural manner, when the listener rotates the direction of the head, the headphone device also rotates with the head, so the sound image perceived by the listener is Relative orientation and position do not change.

When performing pinaural reproduction using a hesodophone device in this way, a sound field is formed inside the listener's head due to differences in the displacement state of the sound image in response to changes in the direction of the listener's head, and the sound image is distorted. It is difficult to localize the sound in front of the listener, and moreover, the sound image in front of the listener tends to rise.

Therefore, conventionally, Japanese Patent Application Laid-open No. 42-227 and Japanese Patent Publication No. 5
4. - As described in Publication No. 19242, by detecting changes in the direction of the listener's head and changing the state of the signal processing described above based on this detection result, it is possible to achieve good performance in a headphone device. An acoustic signal reproduction system that provides a sense of forward localization has been proposed.

In such an acoustic signal reproduction system, a direction detection device 1 such as a so-called gyro compass or a magnetic needle is disposed on the listener's head. Then, based on the detection result by the direction detection device, the level adjustment circuit, delay circuit, etc. that process the acoustic signal are controlled to produce a sound similar to that reproduced by the speaker device arranged at a distance from the listener. It is an attempt to get a sense of place.

D The invention tries to solve i! I! By the way, the conventional high naural playback system in which a direction detecting device such as a gyro compass as described above is installed in a Henodophone device,
In principle, it is possible to obtain a good sense of sound image localization by controlling the content of signal processing applied to the acoustic signal according to changes in the orientation of the listener's head. Since the direction detection device for detecting changes in direction is a large and heavy mechanism, it was necessary to adopt a stationary configuration with a fixed listening position. The problem with the detection device is that it is too large and too heavy to be worn together with a headphone device on the head of a freely moving listener, making it unsuitable for practical use in a portable headphone device.

Therefore, in view of the actual situation in the pinaural reproduction system as described above, an object of the present invention is to enable stable pinaural reproduction using a headphone device worn on the head of a freely moving listener. The present invention provides a headphone device equipped with a head rotation angle detection function that can quickly, accurately, and stably detect changes in the direction of a listener's head.

E. Means for Solving the Problems In order to achieve the above-mentioned object, the headphone device according to the present invention includes a headphone body including a pair of headphone units to which an acoustic signal is supplied from an acoustic signal supply source, and a sound source. a pair of signal detectors that intercept signals for detecting rotation angle information of the listener's head; and supporting means for supporting the signal detectors so that they are positioned respectively, and the pair of signal detectors are attached to the henodophone main body via the supporting means.

F. Function In the henodophone device according to the present invention, the support means supports the pair of signal detectors at a position separated from the henodophone body while the henodophone body is mounted on the listener's head. The pair of signal detectors detect signals for detecting rotation angle information of the listener's head with respect to the sound source while being supported by the supporting means at a position separated from the headphone body worn on the listener's head. feel it.

G. Embodiment Hereinafter, an embodiment of a headphone device in which the present invention is applied to an acoustic signal reproducing device that performs pinaural reproduction will be described in detail with reference to the drawings.

As shown in Fig. 1, this acoustic signal reproduction device is attached to a listener's head using a headband (1), and a pair of headphone units are attached to the listener's left and right pinnae. A hesodophone device (10) is provided to support (2L) and (2R).

The headband (1) of this headphone device (10)
The support arm (3L). Two sliders (4L) and (4R) with protruding protrusions (3R) are slidably mounted, and a pair of sliders (4L) and (4R) that sense the reference signal for position detection sent from the reference signal 'a (l1) are installed. Signal detector (5
L) (5R) is the above support arm (3L), (3R
) is provided at the tip. That is, the pair of signal detectors (5L) (5R) is connected to the hand band (1).
) slider (tag) slidably attached to (411)
Support arm (3L) formed to protrude from . By being provided at the tip of (3R), it is possible to
1) and a pair of headphones Unisoto (2L), (2
R) That is, they are supported by the support arms (3L) and (3R) at a position separated from the headphone body. In this embodiment, the reference signal source (11) includes an ultrasonic signal a (12) and an ultrasonic speaker (13) that sends out the ultrasonic signal from the ultrasonic signal source (12) as a reference signal. It is configured. An ultrasonic microphone is used for each of the pair of signal detectors (5L) and (5R) that sense the reference signal. The ultrasonic wave transmitted from the ultrasonic speaker (13), that is, the reference signal for position detection, is as shown in A of FIG.
Phase detection is possible using Hurst waves, in which ultrasonic waves of a predetermined level are intermittently transmitted at predetermined intervals, or so-called level modulated waves, in which the level changes in a predetermined manner at a predetermined period. This is an ultrasonic wave made by

The pair of signal detectors (5L) provided in the headphone device (10). (5R) senses a reference signal for position detection using ultrasonic waves sent from the ultrasonic speaker (13), and connects the listener to the ultrasonic speaker (13).
3) outputs each detection signal as shown in B and C of FIG.

The above pair of signal detectors (SL). (5R) is a slider (5R) that is slidably attached to the headband (1).
Support arms (3L) and (4R) protrude from each other.
L), (3R), and is provided at the tip of the headband (1) and a pair of headphone units (2L).
, (2R) In other words, when the headphone body is attached to the listener's head, it is supported by the support arms (3L) and (3R) at a position distant from the headphone body, so that the listener does not move or the head Even when the unit is rotated, the ultrasonic waves sent out from the ultrasonic speaker (l3) are extremely well received without obscuring the listener's head, and the reference signal for position detection is detected. Stable and accurate detection is possible. In addition, the pair of signal detectors (5
L). (5R) is the slider (4L) along the headband (1). Slide (4R),
The position can be adjusted to the optimum position for detecting the reference signal for position detection. For example, the navel band (1) may be used to connect the listener's head (the headphone unit, which was previously worn and supported near the listener's left and right auricles) (2).
The positions of L) and (2R) depend on the shape and size of the listener's head (M) and vary from person to person, so please refer to the above. The above pair of signal detectors (5L). Adjust the position of (5R).

Note that in this embodiment, the pair of signal detectors (SL)
, (5R) to the above belly button band (
1) Slider (4L) slidably attached to (
Support arms (3L), (3L) protruding from the support arms (4R),
However, the pair of signal detectors (5L) and (5R) are installed at the tip of the headphone unit (2).
It is also possible to attach the headphone body to the housing of L) and (2R) via a support member so that the headphone body is supported at a position separated from the headphone body while the headphone body is worn on the listener's head. In addition, the above pair of signal detectors (
5L), (5R) are the above sliders (4L),
In addition to adjusting the position by sliding the support arms (4R), for example, the support arms (3L) and (3R) may be supported so as to be pivotable in the direction of the arrow X in FIG. 1 using their base end portions as fulcrums. By the rank! It is also possible to adjust the above signal detector (5L) by using a bearing mechanism, etc.
(5R) itself or the above support arm (3L).
(3R) is rotatably supported in the direction of the arrow Y in FIG. be able to.

These signal detectors (5L). Each detection signal obtained by (5R) is supplied to an arithmetic unit (14).

The arithmetic unit (14) includes the signal detectors (5L) . The first and second edge detection circuits (15
), (16) and the ultrasonic signal [(12), that is, a third edge detection circuit (17) to which the reference signal for position detection is supplied.

The first and second edge detection circuits (15). (1
6) detects each rising edge of each detection signal by each of the signal detectors (5L) and (5R), and generates each pulse signal as shown in D and E of FIG. 2 corresponding to the above rising edges. Output. The first and second edge detection circuits (15). Each pulse signal obtained by (16) is supplied to a distance calculation circuit (18) and a binaural time difference detection circuit (19). Further, the third technology detection circuit (17) detects the rising edge of the ultrasonic signal from the ultrasonic signal source (12), and detects the rising edge of the ultrasonic signal as shown in F in FIG. 2 corresponding to the rising edge. Outputs a pulse signal like this. The pulse signal obtained by the third edge detection circuit (17) is supplied to the distance calculation circuit (18).

The distance calculation circuit (18) corresponds between the pulse signal obtained by the third engine detection circuit (17) and the pulse signal obtained by the first engine detection circuit (15), indicated by ΔT1 in FIG. The time difference tl between the pulses and the third edge detection circuit (shown as ΔT2 in FIG. 2)
17) and the time difference t2 between corresponding pulses in the pulse signal obtained by the second edge detection circuit (16). Based on these time differences t+, tz and the sound velocity V, the arrow l. A distance #l0 between the ultrasonic speaker (13) and the center of the listener's head (A) is calculated.

Note that the sound speed V may be set as a constant in the distance calculation circuit (l8) in advance, and may also be set based on the temperature, humidity,
It may be changed in accordance with changes in atmospheric pressure and the like. In addition, when calculating the distance If, the distance If is calculated based on the positional relationship between each of the signal detectors (5L), (5R) and the center of the head (M), and the shape and size of the head (M). Correction may also be made.

Above distance 2. and each of the above time differences t. , g is
It is sent to the transfer characteristic calculation circuit (20).

The binaural time difference detection circuit (19) has ΔT3 in FIG.
The time difference between the corresponding pulses in the pulse signal of the first edge detection circuit (15) and the pulse signal of the second edge detection circuit (16) shown by is detected. The signal indicating this time difference t is sent to the transfer characteristic calculation circuit (20).
sent to.

In the transfer characteristic calculation circuit (20), each of the time differences L,
, L2, t, the above-mentioned distance Rlo, the above-mentioned sound speed ■, and the above-mentioned radius r of the head (M), the arrow θ is drawn in FIG. An angle θ indicating the direction of the head (M). Calculate. The above angle θ. For example, θo #sin −' (Vz
(t, +tz) Ls /4 rj21...
・It can be determined by (Equation 1). The angle θ indicates the relative positional relationship between this reference position and the listener's head (M), with the position of the ultrasonic speaker (13) as the reference position of the virtual sound source. and distance l0, calculate the rotation angle θ position of the head (M) with respect to the desired virtual sound source position and the relative distance l from the virtual sound source, and calculate the directivity etc. of the desired virtual sound source. Find the transfer characteristics with consideration.

Transfer characteristic information obtained by the transfer characteristic calculation circuit (20) that takes into account the directivity of the virtual sound source, etc. is supplied to the acoustic signal processing circuit (21). And the above headphones Ni-I- (2L), (2
R), the left channel and right channel acoustic signals SL, S, l output from the acoustic signal supply source (22) are passed from the acoustic signal processing circuit (21) to a pair of amplifiers (23L).
)． (23R).

The audio signal supply a (22) supplies predetermined left channel and right channel audio signals SL, S. A device that outputs, for example, various types of recording disk playback devices, recording tape playback devices, or radio wave receiving devices.

The acoustic signal processing circuit (21) processes the left channel and right channel acoustic signals SL, S. first to fourth signal processing units (24a) which are circuits that perform predetermined signal processing on the transfer characteristic calculation circuit (20) and are supplied with transfer characteristic information that takes into account the directivity of the virtual sound source obtained by the transfer characteristic calculation circuit (20); , (24b)
, (24c) and (24d). Each of these signal processing units (24a). (24b) , (24
In c) and (24d), based on the above transfer characteristic information, a pair of loudspeaker devices for the left channel and right channel installed facing the listener and separated from each other are used as virtual sound sources to generate left channel and right channel sound. signal sL,
S. An impulse response is set that expresses the transfer characteristics to each ear of the listener when reproducing .

That is, the first signal processing unit (24a) generates an impulse response {hiR(t,
θ)}. The second signal processing section (24b
) is an impulse response (
h+tL(t, θ)}. The third signal processing unit (24c) sets an impulse response fhLx(t, θ)} that expresses the transfer characteristic of the sound reproduced from the left channel sound signal SL to the right ear. The fourth signal processing unit (24d) sets an impulse response (htt(t. θ)) that expresses the transfer characteristics of the sound reproduced from the left channel sound signal SL to the left ear.

Each of these impulse responses is set in advance in accordance with the transfer characteristics that take into account the directivity of the virtual sound source, and is stored in a memory device (ROM), etc., and the impulse responses are successively generated using the distance @1 and angle θ. may be determined and read.

In this signal processing circuit (21), the right channel acoustic signal Sll is transmitted to the first and second signal processing sections (21).
4a) and (24b). In the first signal processing section (24a), the impulse response (hm
*(t, θ)} signal processing by convolution integral is applied to the right channel acoustic signal Sl. The second signal processing section (24b) also processes the impulse response (
The right channel acoustic signal S is subjected to signal processing by convolution integral of .hat(t, θ)}.

Further, the left channel acoustic signal SL is sent to the third and fourth signal processing sections (24c) and (24d). The third signal processing section (24c) performs signal processing on the left channel acoustic signal SL by convolution integration of the impulse response {hL*(t, θ)}. Further, the second signal processing section (24d) performs signal processing on the left channel acoustic signal SL by convolution integration of the impulse response (hLL(L, θ)).

The output signals of the first signal processing section (24a) and the third signal processing section (24c) are output from the right side adder (25R).
) are added to each other. This adder for the right side (25R
) is sent to the right hesodophone unit (2R) as a right ear acoustic signal Ell via the right amplifier (23R) and reproduced.

Further, the output signals of the second signal processing section (24b) and the fourth signal processing section (24d) are transmitted to the left side adder (25L).
) are added to each other. This adder for the left side (25L
) is passed through the left side amplifier <23L) to the left side Henodophon Unisoto (23L) as a right ear acoustic signal EL.
2L) for playback.

In the acoustic signal reproducing device configured as described above, the position of the ultrasonic speaker (13) is used as a reference position of a virtual sound source, and the relative positional relationship between this reference position and the listener's head (M) is determined. The above angle θ0 and distance @l indicate. From the information, the rotation angle θ position of the head (M) with respect to the desired virtual sound source position and the relative distance from the virtual sound source IViIl
is calculated to obtain a transfer characteristic that takes into account the directivity of the desired virtual sound source, and based on information indicating this transfer characteristic, the left channel and right channel acoustic signals SL, S. is processed in real time. Therefore, in this acoustic signal reproducing device, for example, the fourth A, B ,C shows the relative positional relationship between the virtual sound source and the listener, a pair of speaker devices (SL) are installed in front of the listener (P) and separated from each other so as to face the listener (P). (SR) provides a good sense of off-head localization and forward localization in which the virtual sound source does not move, as in the case of reproducing an acoustic signal.

Here, in FIG. 4, the listener (P) is listening to a pair of loudspeakers (SL) and (SR), that is, a virtual sound source.
B shows a state in which the listener (P) approaches the virtual sound source from the position shown in FIG. There is. This acoustic signal reproducing device performs signal processing that corresponds in real time to changes in transfer characteristics caused by the movement of the listener and the rotation of the head (gate), as described above, to prevent the virtual sound source from moving. A good sense of external localization and a good sense of forward localization can be obtained, and pinaural reproduction corresponding to any of the states A, B, and C in FIG. 4 described above can be performed.

Note that the headphone device according to the present invention is not limited to a structure including a pair of headphone units (2L) and (2R) supported by a headband (1) as in the above-described embodiment, and may be, for example, a laser device or a headphone device. The headphones may have a helmet-type headphone body used by pilots and the like.

H. Effects of the Invention As described above, the henodophone device according to the present invention includes a pair of signal detectors supported by supporting means at positions separated from the henodophone body worn on the listener's head, and Since the signal detector senses the signal for detecting the rotation angle information of the listener's head relative to the sound source, the pair of signal detectors can detect the rotation angle information of the listener's head quickly, with high precision, and Moreover, it can be performed stably.

The detection output from the pair of signal detectors can be used as rotation angle information of the listener's head necessary for processing the pinaural reproduction of the acoustic signal.

Therefore, according to the present invention, it is possible to provide a headphone device that is attached to the head of a freely moving listener and performs stable pinaural reproduction.

[Brief explanation of drawings]

FIG. 1 is a block diagram schematically showing the configuration of an audio signal reproducing device that performs pinaural reproduction using a headphone device according to the present invention, and FIG. 2 is a state of signals supplied to the arithmetic unit of the audio signal reproducing device. FIG. 3 is a schematic diagram showing distances and angles calculated by the arithmetic unit of the audio signal reproducing device, and FIG. 4 is for explaining the operation of pinaural reproduction by the audio signal reproducing device. FIG. 3 is a plan view showing the relative positional relationship between a pseudo-sound source and a listener. (2L). (2R) ・・・・・・(3L)
(3R) ・・・・・・(5L) , (5R)
・・・・・・(10) ・・・・・・・・・・・・ (11) ・・・・・・・・・・・・ (14)・・・・・・・・・(21) ・・・・・・・・・・ Headphone Uninote Support Arm Signal Detector Headphone Device Reference Signal Source Computing Device Acoustic Signal Processing Circuit Patent Applicant Sony Corporation

Claims (1)

[Scope of Claims] A headphone body comprising a pair of headphone units to which an acoustic signal is supplied from an acoustic signal supply source, and a pair of signal detectors for sensing a signal for detecting rotation angle information of a listener's head with respect to the sound source. and supporting means for supporting each of the pair of signal detectors so that the pair of signal detectors are positioned apart from the headphone body when the headphone body is worn on the head of a listener, A headphone device characterized in that a detector is attached to the headphone body via the support means.