JP2787864B2 - Door phone system with TV camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a door phone system with a television camera (hereinafter abbreviated as "camera") and transmits an image from a camera installed at an entrance or the like, a sound from a door phone, and the like through a pair of signal lines. About.

[0002]

2. Description of the Related Art Doorphones and cameras are installed at entrances of houses, and images of visitors and the like taken by the cameras are projected on a television receiver (hereinafter abbreviated as "receiver") in the house, and the images of the receivers are displayed. In a door phone system with a TV camera that allows the user to talk with a visitor via a door phone using a telephone in the house while watching, each signal line that transmits the signal from the camera and the signal from the door phone etc. must be laid from the entrance etc. to the house. In the case of an existing building, wiring work is difficult. If these signals can be transmitted by a pair of signal lines, wiring work will be easier, or if a building has a pair of existing signal lines, it will be possible to install a camera and doorphone using these signal lines .

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such a point, and frequency-modulates a video signal from a camera to a required high-frequency signal, and mixes it with an audio signal of an intercom and transmits the mixed signal. To provide an intercom system with a television camera that can be separated in the house, the high-frequency signal of the camera image is demodulated and input to the receiver, and the image of the visitor etc. can be seen on the screen while talking via the intercom using the telephone. is there.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, according to the present invention, a door phone installed at an entrance or the like calls the inside of a house via a telephone or the like, and a visitor or the like picked up by a camera installed at the entrance or the like. A call button for calling the house, a modulator for frequency-modulating a video signal from the camera to a required high-frequency signal, and a signal by the call button, a signal from the modulator. An entrance unit including a first mixing unit that mixes a signal and a doorphone sound; a separation unit that separates a signal from the entrance unit; a call detection unit that detects a call signal via the separation unit; A switching unit for switching a home telephone or the like to a signal from the separation unit based on a signal from the determination unit; and a demodulation unit for demodulating a high-frequency signal from the separation unit. A demodulation unit, an RF modulation unit that modulates a signal from the demodulation unit into a high-frequency signal of a vacant channel of television broadcasting, a second mixing unit that mixes a signal from the RF modulation unit with a signal line of television broadcasting or the like, A receiver for receiving a high-frequency signal from the second mixer, a receiver for controlling a reception channel of the receiver to receive a signal from the RF modulator based on a signal from the determiner, An object of the present invention is to provide an intercom system with a television camera comprising a discriminating section, a switching section, and a control section for controlling an image receiving control section.

[0005]

As described above, in the intercom system with a television camera according to the present invention, the video signal from the camera is frequency-modulated to a required high-frequency signal, mixed with the audio signal of the intercom, and transmitted to the house. . These are separated in the house, the high-frequency signal is demodulated into a baseband signal, then modulated into a high-frequency signal of an empty channel such as a television broadcast, and input to a receiver. Then, the receiving channel of the receiver is switched to the channel of the image from the camera in response to the calling signal from the entrance or the like, and at the same time, the telephone is switched to the door phone of the entrance or the like and connected.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a door phone system with a television camera according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram of a main part of an embodiment of an intercom system with a television camera according to the present invention. In the figure, A is the entrance and B is the inside of the house. The entrance button 1 is a call button,
For example, a signal line of the door phone 2 or the like is short-circuited by pressing a button. The door phone 2 communicates with a telephone or the like in the house. Reference numeral 3 denotes a camera which images a visitor or the like and outputs a video signal. Reference numeral 4 denotes a modulator, which frequency-modulates a video signal from the camera 3 into a required high-frequency signal. Reference numeral 5 denotes a mixing unit that mixes the high-frequency signal from the modulation unit 4 with the audio signal of the door phone 2.

[0007] A separation unit 6 in the house interior B separates the high-frequency signal and the intercom audio signal from a signal line with the entrance A by an appropriate filter. 7 is a call detection unit,
A signal generated by operating the call button 1 is detected on a signal line from the entrance A through the separation unit 6. 8 is a discriminator,
The call of the entrance A is detected based on the signal of the call detection unit 7. A switching unit 9 switches the line of the telephone 10 from the outside line or the like to the door phone 2 based on a signal from the determination unit 8. 11
Is a demodulation unit for demodulating the high-frequency signal frequency-modulated by the modulation unit 4. Reference numeral 12 denotes an RF modulation unit that modulates the baseband video signal from the demodulation unit 11 into a high-frequency signal of an empty channel such as a television broadcast. A mixing unit 13 mixes the signal from the RF modulation unit 12 into a signal line for television broadcasting or the like. Reference numeral 14 denotes a receiver which receives a high-frequency signal from the mixing unit 13. Reference numeral 15 denotes a receiver control unit, which switches the receiver 14 to a state of receiving a high-frequency signal from the RF modulator 12 based on the signal from the determination unit 8. A control unit 16 controls each unit of the house interior B.

Next, the operation of the intercom system with a television camera according to the present invention will be described. A visitor of the entrance A presses the call button 1. By this operation, the signal line of the door phone 2 is short-circuited. The signal line of the door phone 2 is supplied with power for operation of the door phone from a power source (not shown) installed in a house or the like via a required resistor, and while the call button 1 is being pressed, the signal line is short-circuited. The voltage drops. This drop in voltage is detected by the call detection unit 7 in the house B, and is discriminated by the discrimination unit 8 via the control unit 16. And
Based on the signal from the determination unit 8, the switching unit 9 switches the line of the telephone 10 to the door phone 2 via the control unit 16,
It outputs the required ringing tone and the like. The line of the telephone 10 is connected to the doorphone 2 by the off-hook of the telephone 10, and a call is made with a visitor or the like by a voice signal of the separated doorphone via a required filter or the like of the separation unit 6.

On the other hand, a video signal obtained by imaging by the camera 3 is input to a modulation unit 4, and a high-frequency signal such as 5 MHz is shifted by ± 0.5 MHz or the like and frequency-modulated.
The frequency-modulated high-frequency signal is mixed with the audio signal of the door phone 2 via the mixing unit 5 and transmitted to the inside B of the house. Then, the high frequency signal is separated by a filter or the like of the separation unit 6, input to the demodulation unit 11, and demodulated into a baseband video signal. The video signal from the demodulation unit 11 is input to the RF modulation unit 12 and is modulated into a high-frequency signal of a vacant channel such as a television broadcast. I do.

The control unit 16 receives a signal from the determination unit 8 and
For example, an infrared remote control signal is transmitted from the image reception control unit 15 through the interface, and the reception channel of the image receiver 14 is switched to the channel of the signal from the RF modulation unit 12. In this case, whether or not the receiver 14 is operating is detected by a receiver operation detector (not shown), and if it is not operating, the power of the receiver is turned on, and then the receiving channel is switched. In the above description, the baseband video signal from the demodulation unit 11 is modulated into an empty channel high-frequency signal and input to the receiver, but the baseband is connected to the video input terminal of the receiver as it is, A signal for switching the input of the receiver 14 to the video input may be transmitted from the image reception controller 15 so that the image from the camera 3 is projected on the receiver 14.

[0011]

As described above, according to the intercom system with a television camera according to the present invention, the video signal from the camera at the entrance or the like is frequency-modulated to a required high-frequency signal.
The sound is mixed with the sound of the door phone and transmitted to the house, separated in the house, and the video signal is demodulated and displayed on the screen of the receiver. Therefore, it is only necessary to lay a pair of signal lines between the entrance and the inside of the house, and wiring work is simple, and for example, there is an effect that it can be easily introduced into an existing building.

[Brief description of the drawings]

FIG. 1 is a main block diagram of an embodiment of a door phone system with a television camera according to the present invention.

[Explanation of symbols]

 Reference Signs List A Entrance B Home interior 1 Call button 2 Door phone 3 Television camera 4 Modulation unit 5 Mixing unit 6 Separation unit 7 Call detection unit 8 Discrimination unit 9 Switching unit 10 Telephone 11 Demodulation unit 12 RF modulation unit 13 Mixing unit 14 Television reception Machine 15 Image receiving control unit 16 Control unit

Continuation of front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) H04M 9/00 H04N 7/18

Claims (1)

(57) [Claims] An in-home telephone installed at an entrance or the like calls the inside of a home via a telephone, etc., and simultaneously displays an image of a visitor or the like taken by a television camera installed at the entrance or the like on a television receiver or the like in the home. In the apparatus, a call button for calling a house, a modulation unit for frequency-modulating a video signal from the television camera to a required high-frequency signal, and a signal by the call button, a signal from the modulation unit and a sound of a door phone are mixed. (1) an entrance unit composed of a mixing unit, a separation unit for separating a signal from the entrance unit, a call detection unit for detecting a call signal via the separation unit, and a discrimination unit for discriminating a signal from the call detection unit A switching unit for switching and connecting a telephone or the like in the house to a signal from the separation unit based on a signal from the determination unit; a demodulation unit for demodulating a high-frequency signal from the separation unit; An RF modulator for modulating a signal from the tuning unit to a high-frequency signal of a vacant channel of television broadcasting; a second mixer for mixing a signal from the RF modulator with a signal line for television broadcasting; A television receiver for receiving a higher frequency signal, a reception controller for controlling a reception channel of the television receiver to receive a signal from an RF modulator based on a signal from the determination unit, and the call detection unit, An intercom system with a television camera, comprising a discrimination unit, a switching unit, and a control unit for controlling an image reception control unit.