JPS5944198A - Headphone device - Google Patents

Abstract

PURPOSE:To locate a sound source to a prescribed position even if a head is turned at all times, by detecting a leakage magnetic flux from a deflection coil of a TV receiver so as to detect the turning angle of the head and controlling the acoustic transmission characteristic in response to the turning angle. CONSTITUTION:A magnetic flux A from a deflection coil 4 of the TV receiver 1 is detected at a pickup coil 11 fitted to the head to detect the turning angle theta of the head. An output of the coil 11 is converted into a DC voltage at a DC control signal generating section 12 and its output controls various constants of a signal transfer function converting section 13. The converting section 13 consists of a both-ear time difference control section 14 and a both-ear amplitude difference adjusting section 15 and controls the time difference to both left and right ears and the amplitude in response to the turning angle of the head. Further, the output of an indirect signal generating section 16 sets a level sensing the feeling of distance at the outside of head to the position on a screen of the TV receiver 1. The output of the converting section 13 and the indirect signal generating section 16 controls a headphone drive section 9 and drives headphones 3a, 3b. Thus, even if the head is turned, the sound source is located to the prescribed position.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a telephone apparatus configured to be able to listen to audio signals from a television receiver with headphone sound image localization outside the head.

Conventional configuration and its problems In general, when listening to audio signals from a television receiver through headphones, the localization direction of the sound image perceived by the headphone listener is always a certain direction depending on the movement of the headphone listener. is unchanged. Figure 1 shows how the sound image localization SI changes as perceived by a headphone listener. In the figure, 1 is the television receiver, 2 is the listener, and s
a and sb are headphones.

Now, suppose that the listener 2 feels a sound image ε effect in the direction of the person in front of him, that is, in the direction of the screen of the television receiver 1, when left and right channel signals are input to the headphones 311 and 3b. Next, when the listener 2 turns his head to the right by an angle θ, the sound image S I' also moves by an angle θ, as shown in FIG. It feels like it does. That is, in the conventional headphone listening system, a sound image is always formed with the front of the listener as a reference regardless of the listener's movement θ, so it can be said that it is completely unrelated to the spatial coordinate system of the feeder. Therefore, in the conventional headphone listening system, the direction of the sound image deviates from the screen of the television receiver 1 due to head movement, and the sense of unity of the screen and sound field that is felt when listening to TV sound played through speakers is lost. .

Purpose of the Invention An object of the present invention is to always localize the sound image in a certain spatial direction (for example, toward the center of the TV screen) even when listening with headphones, and to make it possible to determine whether the sound image is localized in the space regardless of the movement of the listener's head. It is an object of the present invention to provide a headphone device that can make a listener feel the sound image localization as if they were listening to sound reproduced by a speaker.

Structure of the Invention The headphone device of the present invention uses the output of a detection section that detects a leakage magnetic field from a deflection coil of a television receiver as a reference magnetic field as a control signal, and uses this control signal to detect an audio signal from the television receiver. The signal source is configured to control the transmission characteristics of a circuit means having a Dohon sound image extra-head localization function in accordance with the movement of the head.

In other words, in order to fix the sound image in an arbitrary absolute space when listening to headphones, the displacement of the listener's head is detected, and this detection signal is used to arbitrarily fix the sound image based on the auditory sound image by the head displacement. It is necessary to provide movement control to the position. Furthermore, the sound image localization of the headphones must be localized outside the head. Therefore, the leakage magnetic field generated by the deflection current flowing through the horizontal deflection coil built into the television receiver is used as the detection means, and the detection means does not require a new original reference magnetic field generator. In other words, it realizes absolute spatial localization of the sound image.

DESCRIPTION OF EMBODIMENTS FIG. 3 shows an embodiment of the present invention. In FIG. An alternating current magnetic field is generated, and since the cabinet of the television receiver 1 is made of a non-magnetic material, a leakage magnetic field is generated outside the cabinet. Therefore, this leakage magnetic field I reaches the vicinity of the listener's 2 head. When a pickup coil 11 for detecting the above-mentioned leakage magnetic field is provided in the main body of the headphone device worn on the head of the listener 2, the induced voltage generated in the pickup coil 11 becomes proportional to the displacement of the listener's head, and the sound image Serves as a control signal for localization control. Here, the configuration is such that the pick-up induced voltage is converted into a DC voltage by a DC control signal generation section 12, and various constants of a signal transfer function conversion section 13 for realizing sound image outside-of-the-head localization are controlled.

The signal transfer function converter 13 and the binaural time difference adjuster 14
, a binaural amplitude difference adjustment section 15, and an indirect signal (Tillet signal) generation section 16. For example, the binaural time difference O1, the binaural amplitude difference ○, and the output of the indirect signal generator 16 are set to be localized at the center position of the screen of the television receiver 1). The state is set to a predetermined level that gives a sense of external distance.

Specifically, the binaural transfer function converter 13 described above is configured as shown in FIG. That is, the analog signal delay element 21.
22, a frequency DC-controlled clock generator 23, 24 for driving the clock generator, and a binaural amplitude difference adjusting unit composed of equalizers 25 to 28 and a DC-controlled polyurethane 29, 30, and a control signal inversion circuit 31. The clock generators 23, 24 . It also controls polyurethane 29.30'jz.

With this control voltage, a binaural time difference commensurate with the rotation angle θ is achieved by frequency control of the 22 clock generators 23 and 24, and one of the clock generators (LCH
]) is higher than the initial reference frequency, and the other (RCH
It is adjusted so that the side) is lowered. In addition, the binaural difference amplitude/adjustment section also controls the level of the DC control volume 29°300 to which the equalizer output is input by the control voltage, so that the level difference between the middle and high frequencies can be set to the desired level difference. It is something that can be done.

In such a configuration, the headphone listening device 2, which was facing the screen of the television receiver 1, turns its head to the right θ.
When rotated for a long time, an induced voltage proportional to the rotation angle θ is generated in the pinoctub coil 11, and the DC control signal generator 1
2 into a DC control signal voltage. The automatic adjustment of the control of the binaural transfer function converting unit 13 using this DC control signal voltage is performed almost in real time so that the reference sound image remains in the fixed position, and the sound field of the actual sound source such as the speaker is heard. Since it can be felt, it is possible to realize more natural extra-head localization reproduction.

By the way, when configuring a complete head rotation detection control loop like this, it is necessary to install a dedicated solenoid or loop coil for generating the reference magnetic field, and also to use a signal amplifier to drive these. In the case of this embodiment, which is applied to headphone listening of the audio signal of the television receiver 1, the loop coil for generating a reference magnetic field for head rotation detection is entirely replaced with the deflection coil of the television receiver, and the loop coil is 15,75 Kt-
Since the AC leakage magnetic field of 1z is used, control of sound image localization can be easily realized.

As described in detail above, according to the invention, the output of the detection section that detects the leakage magnetic field from the deflection coil of the television receiver as a reference magnetic field is used as a control signal, and this control signal causes the television receiver to The head-pond sound image external localization circuit means, whose signal source is the audio signal from death,
This has the advantage that it is possible to give the listener the sensation of being localized in the space regardless of the movement of the listener's head, thereby making it possible to recognize the same sound image localization as when listening through speakers. Furthermore, since the reference magnetic field utilizes the leakage magnetic field of the deflection coil of the television receiver, there is an advantage that a separate magnetic signal generating section is not required.

[Brief explanation of the drawing]

1 and 2 are explanatory diagrams of sound image localization in conventional headphone image reception, FIG. 5 is a block diagram showing an embodiment of the headphone device of the present invention, and FIG. 4 is a specific circuit configuration diagram of the main part of the same device. It is. 1... Television receiver, 2... Listener, 3a, 3b... Headphones, 4...
Deflection coil, 11...Pickup coil, 1
2...DC control signal generation section, 13...Binaural transfer function conversion section.

Claims (1)

[Claims] a detection unit that detects a leakage magnetic field from a deflection coil of a television receiver as a reference magnetic field; a circuit means having a headphone sound image out-of-head localization function that uses an audio signal from the television receiver as a signal source; A dohon device, wherein a control signal is generated based on a detection signal from a detection section, and the transmission characteristic of the sound image extra-head localization circuit means is controlled in accordance with the movement of the head when the headphones are worn.