JPH07190717A - Distance measuring device and audio equipment employing the device - Google Patents

Abstract

PURPOSE:To provide both the distance measuring device capable of accurately measuring a distance between two points in a simple constitution and audio equipment employing the aforesaid device. CONSTITUTION:The device is made up of a light projector LU irradiating light, and of a light receiver RU which is disposed while being faced to the aforesaid projector, and detects light from the projector LU by a semiconductor position detector 50 set inside. The projector LU is made up of a drive means 30 in a rectangular prism shape, and of paired emitting elements 10 and 20 such as LED and the like disposed at its one end surface. Emission by each emitting element 10 and 20 is controlled by the drive means 30. Emission by each emitting element 10 and 20 is controlled by a timing chart, light signals are introduced to a semi-conductor position detector 50, and a distance (d) between light points projected by the emitting elements 10 and 20 while being converged over the semi-conductor position detector 50 and accordingly a distance between the projector LU and the light receiver RU can be operated by an operating section 60 by evaluating the change portion of the ratio of respective signal currents obtained as mentioned above and the like at the operating section 60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a light source which is separated by light.
The present invention relates to a distance measuring device for measuring a distance between points and an acoustic device using the same.

[0002]

2. Description of the Related Art Conventionally, an apparatus for measuring a distance between two points by using a light transmitter and a light receiver separated from each other is: Of measuring the time difference between the two points, or: using a light emitter and a position detection type light receiver, between the two points from the incident angle of light from this light emitter to the position detection type light receiver. There was one that measured the distance.

[0003]

However, in the above-mentioned device, there is a problem that the device becomes complicated because the device for generating the ultrasonic wave and the device for receiving the sound wave from the ultrasonic wave are required. And when ultrasonic waves are used, this speed of sound changes depending on the temperature of the measurement environment,
There was also an essential problem that accurate distance measurement could not be performed.

Further, in the above apparatus, the light projector is always moved along the optical axis of the predetermined light receiver and the light projector, and therefore, when the light projector deviates from this optical axis, a measurement error occurs.

The present invention has been made in view of the above problems, and an object thereof is to provide a distance measuring device capable of accurately measuring a distance between two points with a simple structure.

Further, according to the present invention, such a distance measuring device can be used to output a natural and realistic sound according to the distance between the main body of the device and the auxiliary device attached to the main body. The purpose is to provide.

[0007]

In order to solve such a problem, a first aspect of the present invention is directed to a distance measuring device, in which a first unit provided in a device body is combined with the device body. Second provided in the accessory used
And one unit (LU) of the first or second unit has two light sources (10, 2) arranged apart from each other.
0) and a light source drive circuit (30) for alternately turning on the two light sources (10, 20), and the other (RU) of the first or second unit has two light sources (10, 20). A semiconductor position detector (50) that receives each light emitted from the device and detects each light receiving position, and an arithmetic circuit (60) that calculates the distance from each detected light receiving position to the light source. And

A second aspect of the present invention is directed to an audio device using such a distance measuring device, and a first unit provided in the device body and an accessory device used in combination with the device body. (LU1) is provided with a second unit, and the first unit (LU1) alternately includes two light sources (10, 20) arranged apart from each other and two light sources (10, 20). Light source drive circuit (3
0) and the second unit (RU) receives the respective lights emitted from the two light sources (10, 20) and detects the respective light receiving positions (5).
0) and a calculation circuit (60) for calculating the distance from each detected light receiving position to the light source, and the device body is
Sound reproduction device (300) for outputting a sound signal from a signal source
And a sound adjusting circuit (240, 311 to 316, 321 to 32) that controls the volume or sound quality output from the sound reproducing device (300) based on the distance signal from the arithmetic circuit (60).
6,330-332).

A third aspect of the present invention is a more specific configuration of the sound adjusting circuit portion of the audio equipment of the second aspect of the invention, in which the equipment body is a high frequency component of the sound signal from the signal source (310, 320). And a low-frequency component are separated, and then a high-frequency component is made larger than the low-frequency component to synthesize these components (311 to 313, 315, 321 to 323, 325).
And a sound quality adjusting circuit (314, 324) for controlling the ratio of the high frequency component and the low frequency component synthesized by the high frequency emphasizing circuit (311 to 315, 321 to 325) based on the distance signal from the arithmetic circuit (60). ) And a sound reproduction device (319, 329) that outputs a synthesized sound signal.

The fourth invention is also directed to such an audio device, and the audio device of the second invention is provided with two signal sources (310, 320), and the sound control circuit part This is a more concrete configuration. That is, the device body has two signal sources (310, 320).
An anti-phase emphasis circuit (330 to 332) for increasing the anti-phase component of the sound signal from the same to the in-phase component and adding to each sound signal from the two signal sources (310, 320).
And a sound quality adjustment circuit (331) for controlling the ratio of the in-phase component and the anti-phase component added in the anti-phase emphasis circuit (330, 332) based on the distance signal from the arithmetic circuit (60).
And a sound reproducing device that outputs the added sound signal (319,
329).

Further, a fifth aspect of the present invention is a further development of the sound quality adjusting function of the audio equipment of the fourth aspect of the present invention, wherein the equipment main body has sound signals from two signal sources (310, 320). After separating the high and low frequency components of
A high frequency emphasizing circuit (311 to 313, 315, 321 to 323, 32) that synthesizes the high frequency component and the low frequency component of each sound signal by making the high frequency component larger than the low frequency component.
5) and the opposite phase component of the high frequency component of the sound signal from the two signal sources (310, 320) is made larger than the in-phase component to obtain the respective sound signals from the two signal sources (310, 320). Anti-phase emphasizing circuit for adding (330 to 332)
And the high frequency emphasizing circuits (311 to 313, 315, 321 to 32) based on the distance signal from the arithmetic circuit (60).
3,325) and the sound quality adjustment circuit (314,14) for controlling the ratio of the high frequency component and the low frequency component combined and the ratio of the in-phase component and the anti-phase component added by the anti-phase emphasis circuit (330-332). 324, 331) and a sound reproducing device (319, 320) that outputs a sound signal that is synthesized and added.

[0012]

According to the first aspect of the invention, the two light sources (10, 20) arranged apart from each other are alternately turned on by the light source drive circuit (30), and the light receiving positions of these lights are detected by the semiconductor position detector ( 50), the distance from the semiconductor position detector (50) to the light source is calculated by the arithmetic circuit (60) from the distance between the light receiving positions from each light source and the distance between the two light sources (10, 20). You can ask.

According to the second invention, the volume output from the sound reproducing device (300) is controlled by the volume adjusting circuit (240) portion of the sound adjusting circuit based on the distance signal between the two points thus obtained. Since it is controlled, when the distance between the first unit (LU1) provided with the light source and the second unit (RU) is large, the volume output from the device body is increased,
When approaching, the output volume can be reduced and the volume can be made constant according to the distance. For example, the volume from the stereo audio device (device main body) can be adjusted according to the distance to the viewer who holds the remote control (accessory device). Further, based on the distance signal between the two points thus obtained, the sound quality adjusting circuit (311-31) of the sound adjusting circuit.
6, 321 to 326, 330 to 332) controls the sound quality output from the sound reproducing device (319, 329), and therefore the accessory device (L
It is possible to change the sound quality heard by a viewer who has U1) according to the distance. That is, since the attenuation of the acoustic power at the audible frequency due to the distance between the viewer and the device body is higher as the frequency is higher, the treble region is emphasized when viewing at a long distance, and for a stereo sound source, The sense of presence decreases as the acoustic distance and the distance to the viewer increase compared to the distance between both sound sources, so the in-phase component of the stereo sound source is attenuated and the anti-phase component is emphasized to enhance the sense of presence. To do.

The third invention is a more concrete means for realizing such a constitution. First, a high frequency emphasizing circuit (311 to 313, 315, 321 to 323, 325).
After separating the high-frequency component and the low-frequency component of the sound signal from the signal source (310, 320) by, the high-frequency component is made larger than the low-frequency component and these are combined. Then, the sound quality adjusting circuits (314, 324) perform high-frequency emphasizing circuits (311 to 313, 315, 321 to 3) based on the distance signal obtained from the arithmetic circuit (60) as in the first invention.
23, 325), the ratio of the high frequency component and the low frequency component synthesized can be controlled, and the synthesized sound signal can be output from the sound reproducing device (319, 329).

The fourth invention is also a more concrete means for realizing such a structure, and in particular, the signal source (310,
In the two stereo sound devices of 320), the anti-phase emphasis circuit (330, 332) makes the anti-phase component larger than the in-phase component, and the two signal sources (310, 3)
20) is added to the respective sound signals, and the sound quality adjusting circuit (331) calculates the sound signals based on the distance signal from the arithmetic circuit (60) according to the distance between the viewer and the audio equipment as in the first invention. It is possible to control the ratio of the anti-in-phase component of, and output the added sound signal by the sound reproducing device (319, 329). As a result, auxiliary equipment (LU
Even if the distance between the viewer with 1) and the device body is large, the anti-phase component is emphasized according to this distance, so that the sense of presence can be enhanced.

Particularly, as in the fifth aspect of the invention, the high frequency emphasizing circuit (311 to 313, 315, 321 to 323, 32).
According to 5), after separating the high frequency component and the low frequency component of each sound signal from the two signal sources (310, 320), the high frequency component is made larger than the low frequency component and In addition to synthesizing the low frequency component, the anti-phase emphasizing circuit (330 to 332) makes the anti-phase component of the high-frequency component of the sound signal larger than the in-phase component, so that the respective sound signals from the two signal sources are obtained. If this is output by the sound reproduction device (319, 320) by adding, the viewer can obtain a sound with a very realistic sensation according to the distance between the viewer holding the accessory device (LU1) and the device body. I can listen.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment according to the present invention will be described below with reference to the accompanying drawings. The same elements will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a diagram for explaining a distance measuring device and its measuring principle according to an embodiment of the present invention. As shown in FIG. 7A, the distance measuring device of the present embodiment is a semiconductor position detector 50 in which a light projector LU for irradiating light and a light projector LU are arranged so as to face the light projector LU and light from the light projector LU is installed therein.
(Hereinafter referred to as PSD50), and a light receiver RU for detection.

The projector LU comprises a rectangular parallelepiped driving device 30 and a pair of light emitting elements 10, such as LEDs, arranged on one end face of the driving device 30.
20 and 20. The light emission of the light emitting elements 10 and 20 is controlled by the driving device 30. The installation distance D between the light emitting elements 10 and 20 is equal to the size of the projector LU,
It depends on the size of the light receiving part of the PSD 50, the length of the measurement distance, etc., but at a measurement distance of about 3 m, it is about 3 to 5
cm is suitable. Further, regarding the drive current, it is necessary to change the current according to the distance, but a maximum value of about 200 mA is suitable for the distance measurement of about 3 m.
When the driving frequency of the driving device 30 also serves as a light source for optical data transmission as described later, for example, it is appropriate that the driving frequency is around 40 kHz, which means that when the pair of light emitting elements 10 and 20 are alternately turned on, the PSD 50 emits light. This is because it is desirable to blink at an apparent frequency of about 40 kHz. The receiver RU is
They are arranged on the extension lines of the light emitted from the respective light emitting elements 10 and 20. A lens 40 is fixed to one end surface of the light receiver RU, and the light emitted from the light emitting elements 10 and 20 is provided in the PSD inside the light receiver RU.
It is focused on the light receiving surface of 50. The PSD 50 and the lens 40 are separated by the focal length f of the lens 40.

Here, the light emission of the light emitting elements 10 and 20 is controlled according to the timing chart as shown in FIG. That is, the light emitting element 10 and the light emitting element 20
Respectively emit light alternately to generate an optical pulse signal. Then, this optical pulse signal is introduced into the PSD 50.
From the two signal electrodes of the PSD 50, the distance D between the light emitting elements 10 and 20, the lens focal length f of the PSD 50, and the distance L between the light emitter LU and the light receiver RU (lens 40) are determined for each optical pulse signal of one pulse. The signal is obtained.

That is, by evaluating the change amount of the ratio of the respective signal currents I ₁ and I ₂ obtained from the PSD 50 by the arithmetic unit 60 of the PSD 50, the light spots from the respective light emitting elements 10 and 20 focused on the PSD 50 are evaluated. The interval d can be calculated by the calculation unit 60. Here, since the distance D and the lens focal length f are known, the distance L between the light emitter LU and the light receiver RU can be obtained according to the principle of triangulation.

That is, when the distance between the position irradiated from the light emitting element 10 and incident on the light receiving element 50 and the position irradiated from the light emitting element 20 and incident on the light receiving element 50 is d,
The distance d between the two light spots is d = f × (D / L) (Equation 1), which is inversely proportional to the distance L between the light receiver RU and the light emitter LU, so the distance d is calculated. It is possible to obtain these distances L from (Equation 1). For example, f
= 10 mm, D = 50 mm, d = 0.5 mm,
It is calculated as L = 1000 mm. However, the absolute value of each signal current is the distance (L + f) between the projector LU and the PSD 50.
Since the magnitude of the light changes depending on the light emitting direction of the projector LU, the driving current, and the like, the signal current I ₁
After logarithmically converting I ₂ and I ₂ , it is desirable to take the ratio of both. It should be noted that FIG. 7C shows the signal currents I ₁ and I _1.
The relationship between the absolute value of the difference of ₂ and the distance L is shown, and FIG. 7D shows the appearance of the projector LU.

Next, the light receiver RU will be described in more detail. FIG. 2 is an example in which the light receiver RU of the distance measuring device shown in FIG. According to such a configuration, the ratio of the signal current proportionally distributed by the PSD 50 according to the incident position of the optical signal is calculated by the calculation unit 60. Then, the calculation unit 60 outputs the distance signal based on the magnitude of this ratio. The arithmetic unit 6
0 is the second light receiver (eg, photodiode) 8
0 and the timing signal generating circuit 70 are connected, and P
The sampling of the signal input from the SD 50 to the calculation unit is performed based on the optical signal received by the second light receiver 80.

FIG. 3 is a diagram showing a more specific structure of the light receiver LU shown in FIG. This light receiver LU operates as follows. First, in the PSD 50, the light emitting element 10
The signal currents due to the emission of 20 and 20 are detected. Next, the signal current is converted into the logarithmic amplifier 601 for the reason described above.
a and 601b are logarithmically converted to obtain the ratio of both. The voltage value of this voltage is held by each of the sample and hold circuits 602a and 602b. Since the held voltage difference is input to the differential amplifier 603, the logarithmic signal voltage difference, that is, the optical signal intensity ratio can be obtained.
The output signal from the differential amplifier 603 is rectified by the peak rectifier circuit 604.

Then, the series of operations are alternately repeated for the pulsed light from the pair of light emitting elements 10 and 20. Therefore, the PS from the output terminal of the differential amplifier 603.
An AC voltage having a peak-to-peak value proportional to the distance d between the two light spots incident on D50 can be obtained. Therefore, from the distance d to the distance between the light emitter LU and the light receiver (L + f)
Can be calculated.

The sample hold circuit 602 described above is used.
a and 602b are driven by the timing signal generation circuit 70. That is, the second light receiver 80 is installed in the vicinity of the PSD 50, and detects and amplifies the optical signal alternately emitted from the light emitter LU. Then, the timing signal generation circuit 70 generates a timing signal for performing sample hold in the sample hold circuits 602a and 602b based on the signal from the light receiver 50. With such a configuration, the signal-to-noise ratio does not deteriorate even when the measurement distance is long, and malfunctions due to background light can be reduced.

A photodiode, a PIN photodiode, an avalanche photodiode, or the like can be used as the second photodetector 80. From the viewpoint of preventing malfunction, a cut filter for the background light component is provided. , Optical receiver for optical remote control is desirable.

Further, the sample hold circuits 602a, 602a, 6
It is also possible to add a signal obtained from the PSD 50 to an adder (not shown) and take it out when driving the 02b, but this is generated by using the second photodetector 80 to generate timing. Compared to the case, the SN ratio deteriorates in long-distance measurement, and malfunctions due to background light increase.
In addition, the pulse code modulation (PC
When M) is applied, this timing signal can be used for various data transmissions by passing through the pulse code demodulator 160. Further, the output of the distance signal can be stopped based on the data demodulated by the pulse code demodulator 160. Examples of such a stopping method include a configuration in which the output of the differential amplifier 603 that differentially amplifies the output signal from the PSD 50 is cut off.

Next, the projector LU and the receiver RU (PSD5
The positional relationship with 0) will be described. FIG. 4 is a diagram in which these arrangements are observed from a viewpoint perpendicular to the plane formed by the light emitting elements 10 and 20 and the PSD 50. The figure (a) is
When the PSD 50 is on the optical axis of the light receiver, FIGS. 7B and 7C show the positional relationship when the PSD 50 is displaced from the optical axis in the plane.

FIG. 5 shows the signal waveforms corresponding to these (a) to (c). Since the operation of the logarithmic amplifier is self-explanatory, it is omitted. As is clear from FIG. 5, even if the positions of the light emitter LU and the light receiver RU deviate from the optical axis, the distance signal (I ₁ -I ₂ ) obtained by differentially amplifying the output of the PSD 50 corresponding to the distance signal is It does not change. Similarly, even if there is direct current background light, since the position signal is obtained from the output of the differential amplifier in order to output the distance signal, there is no distance measurement error.

However, in order for the distance measuring device of the present invention to operate precisely, the line connecting the light emitting elements 10 and 20 of the projector LU is the light receiving surface of the PSD 50 (preferably in the longitudinal direction).
Must be placed parallel to. However, when not arranged in this way, that is, since the distance measurement error due to non-parallel deviation is determined by the cosine of the deviation angle, when the deviation is small, this error can be ignored. For example, when adjusting the sound quality between a television and a stereo audio device, or when detecting the distance between the wall of a parking lot and the vehicle, the error caused by this deviation angle is a few percent, which is a particular problem. I won't.

Next, the magnitude of the received light signal will be examined. As a condition, the distance measured is 1 m, and the light emission output is 40 mW / s
It is assumed that the LED of r is turned on at a distance of 5 cm from the PSD 50 (light receiver), the diameter of the lens 40 is 5 mm, and the focal length f is 10 mm. The input signal light output of the PSD 50 at this time is 0.79 × 10 ⁻⁶ W in terms of optical power, and if it is assumed that all of these are incident on the light receiving surface of the PSD 50 having a photoelectric conversion sensitivity of 0.5 A / W, the PSD 50 Of 2
The total signal current obtained from one signal electrode is about 0.4 ×
It is 10 ^-6 A. At this time, the center distance between the two light spots is shown in FIG.
It is 0.5 mm from the formula 1 described above, and it means that the vehicle reciprocates repeatedly during this period. If the displacement center of the light spot is PSD5
When the PSD 50 has a length of 3 mm, the photocurrent generated at each electrode of the PSD 50 is ± 0 with respect to 0.4 × 10 ⁻⁶ A, which is half the above, when the PSD 50 has a center of 0. .25
It will be reduced by / 3. Also, the condition (b) in FIG.
When incident on a portion other than the center of the PSD 50 as shown in (c) and (c), each signal current corresponding to the amount of movement of the center of shift of the light spot from the center of the PSD 50 is modulated at the above ratio and obtained from each electrode. .

As described above, in the distance measuring apparatus according to the present invention, the distance measuring error due to the non-parallel deviation can be ignored when the deviation is small. It can be applied to a device. Hereinafter, an example in which the distance measuring device according to the present invention is applied to an audio device will be described. First, an example in which the distance measuring device is used to adjust the volume of an audio device will be described.

When turning on the switch of the audio equipment by remote control, it is preferable to activate the audio equipment at a low volume so that a large volume is not generated carelessly. However, since the distance between the viewer and the audio device is indefinite, this volume cannot always be said to be appropriate. Therefore, if the distance measuring device according to the present invention is applied to an audio device, the distance can be automatically determined in advance when the power of the audio device is turned on. Therefore, the distance between the viewer having the projector and the audio device can be determined. The audio device can be activated at an appropriate volume according to the sound volume. In addition, the volume can be adjusted by determining the distance even after the audio device is started.

FIG. 6 is a block diagram showing an embodiment of an audio device (device main body) having an automatic volume adjusting function using such a distance measuring device. In this embodiment, the volume of the television receiver incorporating the audio equipment can be adjusted according to this distance.

The remote control projector LU1 is a remote controller (accessory device) for a television in which the projector LU shown in FIG. 3 is incorporated. A remote controller for a television receiver is a conventional remote controller, which is, for example, a device that code-modulates the light emission of an infrared light emitting diode, and uses this signal to turn on / off the television receiver, adjust the volume quality, and select a channel.

First, the distance signal obtained from the light receiver RU shown in FIG.
Input to 0. For example, during this sampling,
The pulse width T _W of the sampling pulse is 50 μs, and the frequency thereof is 1 kHz. Then, the held signal is input to the electronic volume 240 configured by a variable resistor or the like via the changeover switch 250 (S ₁ is turned on) to control the output of the signal from the signal source 230. That is, in the state where the switch of the television receiver is turned on, the electronic volume is adjusted so that the output obtained from the signal source 230 increases as the distance between the viewer having the remote control projector LU1 and the light receiver RU increases. 240 may be controlled. Then, the signal from the signal source whose output is adjusted according to the distance signal in this way is amplified by the amplifier 290 and output from the speaker 300.

Further, since the projector LU1 with remote control is equipped with a conventional remote control, the remote control light receiving section 200 of the remote control constituted by using a photodiode or the like detects the signal from the remote control, and The electronic volume 280 can be controlled by causing S ₂ of the changeover switch 250 to pass therethrough based on the signal. The electronic volume 280 can also be controlled manually. Further, the power switch 260 of the television can be turned on / off by a signal received by the remote control receiving unit 200. The power of the power switch 260 of the television is supplied from the AC power supply via the plug 410, and can also be supplied from the auxiliary power supply 270 as shown in FIG. Further, when it is desired to start up the television receiver at an optimum volume, the remote control light projector LU1 is generated at the same time when a signal for turning on the power switch 260 is generated from the remote controller of the remote control light projector LU1.
By turning on the projector LU in the interior, the television receiver can be started at a volume corresponding to the distance to the viewer. It should be noted that such an automatic volume control function can be applied not only to monaural audio equipment but also to stereo audio equipment.

Next, a television receiver whose sound quality can be adjusted according to this distance will be described. The higher the frequency, the greater the attenuation of the acoustic power at the audible frequency due to the distance between the viewer and the audio equipment. Therefore, when viewing at a long distance, it may sound more natural to emphasize the treble region. Also, for a stereo sound source, the sense of realism decreases as the acoustic distance and the distance to the viewer increase compared to the distance between the two sound sources. Therefore, in such a case, the in-phase component of the stereo sound source is attenuated and the anti-phase component is emphasized to enhance the sense of presence.

FIG. 7 is a diagram showing the configuration of a stereo audio device having an automatic sound quality adjustment function to which the distance measuring device according to the present invention is applied. Similar to the embodiment shown in FIG. 6, the distance signal output from the light receiving unit LU of the distance measuring device is the sample hold circuit 220 and the changeover switch 250.
Left and right electronic volume 3 via (turn on S ₁ )
Adjust 14 and 324. That is, for example, if the output of the distance signal increases as the distance between the remote control projector LU1 and the light receiving unit 210 increases, the electronic volume control 314 increases as the output of the distance signal increases.
And 324 to control the left and right signal sources 310, 320.
Amplifies the high frequency components of the signal.

This high frequency component is generated by the left and right signal sources 310, 3
It is obtained by operating the high-pass filters 312 and 322 on the signal from 20 respectively. As shown in the figure, the high frequency component is amplified by the amplifier in this embodiment. The low-frequency components of the signals from the left and right signal sources 310 and 320 have low-pass filters 311 and 3 added to this signal.
21. The high-frequency components and the low-frequency components of these are obtained by multiplying the crossover circuits 315, 325.
Re-synthesized by. In addition, the left and right signal sources 310, 3
The high frequency component of the signal output from 20 is adjusted by the electronic volumes 314 and 324, and then input to the differential amplifier 330 to detect the antiphase component included in this high frequency component. Then, the output of the anti-phase component included in this high frequency component is amplified by the variable gain amplifier 331 that operates based on the distance signal output from the light receiver RU.

As described above, in the case of a stereo sound source, the sense of presence can be emphasized by emphasizing the anti-phase component compared to the in-phase component. Whether or not the opposite phase component is emphasized in this way can be selected by controlling the changeover switch 332 according to a signal received by the remote control receiving unit 200. The antiphase component included in the high frequency component is amplified as the distance increases, and the crossover circuit 31
6, 326, the high frequency component and the low frequency component are further combined into a combined signal. Thereafter, the left and right combined signals are transmitted to the speakers 319 and 329 via the electronic volume controls 317 and 327 and the amplifiers 318 and 328.
Are output respectively.

As described above, the acoustic device with the automatic sound quality adjustment function can reproduce a natural and realistic sound according to the distance from the stereo sound source. Note that such control regarding sound quality can also be performed by automatically determining the distance when the power of the audio device is turned on, similarly to the audio device with the automatic volume control function. Note that it is also possible to apply the above-described automatic volume adjustment function and automatic sound quality adjustment function to a single audio device.

In the embodiment described with reference to FIGS. 6 and 7, the light receiver RU is assumed to be attached to the audio equipment, and the light emitter LU is attached to the remote control which is the accessory equipment. This may be the reverse configuration if the acoustic device and the remote controller are electrically or electromagnetically connected, that is, the light receiver RU is mounted on the remote controller and the projector LU is mounted on the acoustic device. Further, in the above embodiment, the PSD 50 is used as the semiconductor position detecting device 50, but a MOS type image sensor or a CCD image sensor may be applied as long as it can detect the light receiving position from the light source.

[0045]

As described above, according to the first aspect of the invention, the distance from the semiconductor position detector to the light source can be obtained from the light receiving position of each light source detected by the semiconductor position detector.

According to the second aspect of the invention, the volume output from the sound reproducing device is increased when the viewer having the light source is separated from the device body, and the sound is output when the viewer is near the device body. By reducing the volume output from the playback device, the volume heard by the viewer can be made constant according to the distance. In particular, when starting up the device body, it is desirable to start up at a required low volume, and the volume at startup can be adjusted based on the distance to the viewer. Furthermore, since the sound quality output from the sound reproducing device is controlled by the sound adjusting circuit based on the distance signal between the two points obtained in this way, the viewing depending on the distance between the viewer holding the light source and the device body. The sound quality heard by a person can be changed according to the distance.

According to the third aspect of the invention, the high frequency component of the sound signal from the signal source is emphasized by the high frequency emphasizing circuit according to the distance from the light source, so that the attenuation of the high frequency component due to the distance increases is compensated for naturally. You can enjoy great music.

According to the fourth aspect of the invention, in a stereo audio device having two signal sources, the anti-phase component can be emphasized by the anti-phase emphasizing circuit according to the distance to the viewer who holds the light source. , It can enhance the realism of the sound.

In particular, as in the fifth aspect of the invention, in a stereo audio device having two signal sources, the high frequency emphasizing circuit compensates the attenuation of the high frequency component due to the distance, while the anti-phase emphasizing circuit suppresses the high frequency component. Since the anti-phase component is emphasized, the viewer can hear a sound with a very realistic sensation according to the distance.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating a distance measuring device and a measuring principle according to an embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating a configuration of an embodiment of a distance measuring device according to the present invention.

FIG. 3 is a more specific configuration diagram of the distance measuring device shown in FIG.

FIG. 4 is an explanatory diagram illustrating a principle of distance detection based on a position shift of the distance measuring device according to the present invention.

5 is a diagram showing an example of a waveform of a distance signal obtained from the distance measuring device shown in FIG.

FIG. 6 is a configuration diagram of an audio device according to the present invention.

FIG. 7 is a configuration diagram of an audio device according to the present invention.

[Explanation of symbols]

10, 20 ... Light emitting element, 30 ... Driving device, 40 ... Lens, 50 ... Semiconductor position detector, 60 ... Computation unit, 80 ... Second light receiver, 601a, 601b, 220 ... Sample and hold circuit, 603, 330 ... Differential amplifier, 604 ... Peak rectifying circuit, 70 ... Timing signal generating circuit, 80 ...
Second light receiver, 160 ... Pulse code demodulation circuit, 200
... remote control receiver, LU ... light receiver, 230 ... signal source, 2
40, 280, 314, 324, 251, 317, 32
7 ... Electronic volume, 250, 260, 332 ... Changeover switch, 270 ... Auxiliary power supply, 290 ... Amplifier, 30
0,319,329 ... Speaker, 410 ... Plug, L
U1 ... Projector with remote control, 310 ... Left signal source, 320 ...
Right signal source, 311, 321 ... Low-pass filter, 31
2,322 ... High Pass Pfister, 313,323,3
18,328 ... Amplifier, 315, 325, 316, 32
6 ... Crossover circuit, 331 ... Variable gain amplifier.

Claims (5)

[Claims] 1. A first unit provided in a device body, and a second unit provided in an accessory device used in combination with the device body, wherein one of the first and second units is separated. And a light source drive circuit that alternately turns on the two light sources, and the other of the first and second units is a light source that emits light from the two light sources. A distance measuring device, comprising: a semiconductor position detector that receives light to detect respective light receiving positions; and a calculation circuit that calculates a distance from each of the detected light receiving positions to the light source. 2. A first unit provided in a device body, and a second unit provided in an accessory device used in combination with the device body, wherein the first unit is arranged separately. It has two light sources and a light source drive circuit that alternately lights the two light sources, and the second unit receives each light emitted from the two light sources and detects each light receiving position. Having a semiconductor position detector and an arithmetic circuit for calculating a distance from each of the detected light receiving positions to the light source, the device body, a sound reproducing device for outputting a sound signal from a signal source, and A sound adjusting circuit for controlling the volume or sound quality output from the sound reproducing device based on the distance signal from the arithmetic circuit. 3. A first unit provided in a device body, and a second unit provided in an accessory device used in combination with the device body, wherein the first unit is arranged separately. It has two light sources and a light source drive circuit that alternately lights the two light sources, and the second unit receives each light emitted from the two light sources and detects each light receiving position. And a semiconductor position detector, and an arithmetic circuit that calculates a distance from each of the detected light receiving positions to the light source, and the device body separates a high frequency component and a low frequency component of a sound signal from a signal source. After that, a high-frequency emphasis circuit that makes the high-frequency component larger than the low-frequency component and combines them, and a high-frequency component that is combined by the high-frequency emphasis circuit based on the distance signal from the arithmetic circuit. Audio equipment, characterized in that it comprises a sound quality adjusting circuit for controlling the ratio of the frequency components, a sound reproduction device for outputting the synthesized sound signal. 4. A first unit provided in the device body, and a second unit provided in an accessory device used in combination with the device body, wherein the first unit is arranged separately. It has two light sources and a light source drive circuit that alternately lights the two light sources, and the second unit receives each light emitted from the two light sources and detects each light receiving position. And a computing circuit that computes the distance from each of the detected light receiving positions to the light source, and the device body has the same phase of the antiphase components of the sound signals from the two signal sources. An anti-phase emphasizing circuit that is made larger than the component and is added to each sound signal from the two signal sources, and an in-phase component that is added by the anti-phase emphasizing circuit based on the distance signal from the arithmetic circuit. Audio equipment, characterized in that it comprises a sound quality adjusting circuit for controlling the ratio of the reverse phase component, and a sound reproduction device for outputting the summed audio signal. 5. A first unit provided in the device main body, and a second unit provided in an accessory device used in combination with the device main body, wherein the first unit is arranged separately. It has two light sources and a light source drive circuit that alternately lights the two light sources, and the second unit receives each light emitted from the two light sources and detects each light receiving position. And a computing circuit that computes the distance from each of the detected light receiving positions to the light source, and the device body has a high frequency component and a low frequency component of each sound signal from two signal sources. A high-frequency emphasizing circuit for separating the high-frequency component from the low-frequency component after separating the high-frequency component and synthesizing the high-frequency component and the low-frequency component of each sound signal; and the sound signals from the two signal sources. An anti-phase emphasizing circuit for increasing the anti-phase component of the high-frequency component to be larger than the in-phase component and adding to the respective sound signals from the two signal sources, and the high-frequency emphasizing based on the distance signal from the arithmetic circuit. A sound quality adjusting circuit for controlling a ratio of a high frequency component and a low frequency component synthesized by a circuit and a ratio of an in-phase component and an anti-phase component added by the anti-phase emphasis circuit; and the synthesized and added sound signal. And a sound reproducing device for outputting the sound.