JPH0983854A - Sound collection device for camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To harmonize video image and voice in an excellent way by providing a built-in microphone and an external microphone and selecting a sound signal of any microphone or both the microphones corresponding to a zoom ratio at image pickup. SOLUTION: A camera 2 converts a light from an object magnified by an optical zoom device 1 into a video signal and it is outputted to a VTR 3 and recorded on a magnetic tape. An external microphone 4 is made up of a wireless microphone being a separate body from the camera and arranged in the vicinity of an object, a radio wave modulated by the collected sound signal is sent and fed to an output circuit 5 installed in the vicinity of the camera. The output circuit 5 demodulates the received radio wave and sends the sound signal to the camera via an external microphone terminal 6. A control circuit 15 receives zoom ratio information from a zoom encoder 14 to control switches 8, 9, 13 to select a sound signal suitable for a field angle, e.g. the built-in microphone 7 for a wide angle mode, mixture of the built-in microphone 7 and the external microphone 4 for a standard mode, and the external microphone 4 for a telescopic mode respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound collecting device, and more particularly to a sound collecting device used for a camera having an optical and / or electronic zoom device or a camera-integrated VTR.

[0002]

2. Description of the Related Art Conventionally, a camera-integrated VTR that is generally commercially available has a built-in unidirectional or omnidirectional microphone, and together with an image taken by a camera unit,
The sound collected by the built-in microphone is recorded on the magnetic tape.

[0003]

However, while the camera unit has an optical and / or electronic zoom device to enlarge the screen, the built-in microphone is mainly used for a fixed sound collection range. Since I only have it, there was a problem that I could not pick up sounds that were unrelated to the screen range or could not pick up the necessary sounds on the screen.

As a solution to this problem, there is a method using a zoom microphone. FIG. 2 shows a conventional example of a camera-integrated VTR using a zoom microphone. The zoom encoder 22 detects the zoom ratio of the optical zoom device 21, and the control circuit 24 controls the characteristics of the zoom microphone 23 in conjunction with the zoom ratio to control the image output from the camera device 25 to the VTR 26. Even if the zoom ratio changes, the audio output from the zoom microphone 23 to the VTR 26 via the amplifier 27 and recorded can be matched.

However, since the zoom ratio is detected and the zoom microphone 23 is controlled, the circuit becomes complicated. Also,
Since the zoom microphone 23 is expensive and it is difficult to obtain a zoom ratio that is too high even with a zoom microphone, there is a problem that it is difficult to obtain the zoom amount of the microphone that corresponds to the high zoom ratio of the screen.

The present invention is an inexpensive VTR including a camera and an optical and / or electronic zoom device, which is capable of recording images and voices that match the human sense without causing any discomfort in the images and voices. The purpose is to provide.

[0007]

In order to solve the above problems, the present invention provides a sound collecting device for a camera having an optical and / or electronic zoom device, in which a built-in microphone and a sound collecting device body are provided separately. An external terminal to which an output signal from an external microphone is supplied, a mixing circuit which mixes the output signals from the built-in microphone and the external terminal, an output signal from the built-in microphone, an output signal from the external terminal, and the mixing circuit And a selection circuit for selectively outputting the output signal from the circuit.

Further, the external microphone is arranged in the vicinity of an object photographed by the camera, the selection circuit is controlled by the zoom ratio of the optical and / or electronic zoom device, and the zoom ratio changes from wide angle to telephoto. According to the above, the output signal from the built-in microphone, the output signal from the mixing circuit, and the output signal from the external terminal are selected.

Further, a wireless microphone is adopted as the external microphone.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a functional block diagram showing a camera-integrated VTR which is an embodiment of the present invention. In the figure, reference numeral 1 denotes an optical zoom device, which magnifies light from a subject and guides it to a camera device 2. Then, the camera device 2 converts the light from the subject into a video signal and outputs it to the VTR 3. The VTR 3 records the video signal on a magnetic tape together with an audio signal described later.

On the other hand, 4 is a wireless microphone which is an external microphone arranged near the subject separately from the camera-integrated VTR main body, and 5 is an output circuit which receives the radio wave from the wireless microphone 4 and demodulates it to output an audio signal. 6 is an external microphone terminal provided on the main body, and 7 is a built-in microphone. 8, 9
Are switches connected to the H side when mixing the inputs from the external microphone terminals 6, respectively. 10, 11 are
With the amplification circuit of wireless microphone 4 and built-in microphone 7,
The output is output to the mixing circuit 12. The mixing circuit 12 mixes the voice of the wireless microphone 4 and the voice of the built-in microphone 7. The switch 13 selects the mixed audio signal and the audio signal of only the built-in microphone, and outputs the selected audio signal to the VTR 3.

Reference numeral 14 is a zoom encoder for detecting the zoom ratio of the optical zoom device 1, and the value of the zoom ratio detected by the zoom encoder 14 is input to the control circuit 15. The control circuit 15 switches the switches 8, 9 and 13 according to the value of the zoom ratio.

Next, the operation will be described. The audio signal picked up by the wireless microphone 4 arranged near the subject is output from the output circuit 5 to the external microphone terminal 6 via radio waves.
As a result, the sound around the wireless microphone 4, that is, the sound around the subject is input to the main body. A voice signal from the built-in microphone 7 is input to the amplifier circuit 11 through the switch 9. As a result, the sound of the photographer, that is, the sound around the main body is input to the device. The audio signals input from the wireless microphone 4 and the built-in microphone 7 are amplified by the amplifier circuits 10 and 11, respectively, and then input to the mixing circuit 12. The output of the mixing circuit 12 is selected by the switch 13, and the VTR3
Is output to

Then, the control circuit 15 includes the optical zoom device 1.
As the zoom ratio of changes from wide angle to telephoto, the switches 8, 9 and 13 are switched as shown in the following table.

[0015]

[Equation 1]

That is, the switch 8 and the switch 13 are controlled so as to be H when the wireless microphone 4 which is an external microphone and the built-in microphone 7 are used at the same time. Switch 9
Turns on only when the signal from the built-in microphone 7 is used.

Although the embodiment of the present invention has been described above, the switches 8, 9 and 13 may be manually switchable. The external microphone is not limited to a wireless microphone, and a normal microphone may be used and connected to the external input terminal of the main body with a cable. Furthermore, it goes without saying that either an electronic zoom device or both may be used instead of the optical zoom device.

[0018]

As described above, by providing the external microphone, the built-in microphone, and the mixing circuit for mixing the outputs of both microphones, not only the sound around the built-in microphone but also the sound near the subject on the screen Can be imported as needed, so
It is possible to provide an inexpensive sound collecting device for a camera that can record images and sounds that match the human sense without causing discomfort in the screen and sounds, and the effect thereof is great.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing an embodiment of the present invention.

FIG. 2 is a functional block diagram showing a conventional technique.

[Explanation of symbols]

 1 Optical Zoom Device 2 Camera Device 3 VTR 4 Wireless Microphone (External Microphone) 6 External Microphone Terminal 7 Built-in Microphone 8 Switch 9 Switch 12 Mixing Circuit 13 Switch 14 Zoom Encoder 15 Control Circuit

Claims (3)

[Claims] 1. A sound collecting device for a camera having an optical and / or electronic zoom device, a built-in microphone, an external terminal to which an output signal from an external microphone provided separately from the sound collecting device body is supplied, and the built-in device. A mixing circuit that mixes output signals from a microphone and the external terminal, and a selection circuit that selectively outputs the output signal from the built-in microphone, the output signal from the external terminal, and the output signal from the mixing circuit. And a sound collecting device for a camera. 2. The external microphone is arranged in the vicinity of a subject photographed by the camera, the selection circuit is controlled by a zoom ratio of the optical and / or electronic zoom device, and the zoom ratio changes from wide angle to telephoto. 2. The sound collecting device for a camera according to claim 1, wherein the output signal from the built-in microphone, the output signal from the mixing circuit, and the output signal from the external terminal are selected in accordance with the above. 3. The sound collecting device for a camera according to claim 1, wherein the external microphone is a wireless microphone.