JPS6038997A - Picture information reproducing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an image information reproducing apparatus, and for example, to a video tape recorder (hereinafter referred to as a VTR) for reproducing image information recorded on a magnetic tape.

[Description of Prior Art] Conventional VTRs generally provide their output signals to a television receiver via an RF converter to display images on brown snow for viewing.

In this case, a method is adopted in which a -[RF converter emits radio waves via a mini transmitter and the radio waves are received by a receiver.

1 and 2 are diagrams showing television signals.

In the NTSC system, the transmission band is 6M as shown in Figure 1.
It is a sideband method of H2, and the bandwidth of the luminance signal is 4.5M.
)12, but 3M) Color signals are interleaved multiplexed in bands of 12 and above, and even for the brown signal, one signal has a bandwidth of 1°5MH7 band, and the Q signal is 0.5M.
It is H2 band, ■.

Both Q signals are transmitted using quadrature modulation. On the receiving side, synchronous detection of the (RY) and (8-Y) signals is performed, and the reproduced output signal is limited to 500 kHz.

When actually recording image signals on a home VTR,
As shown in FIG. 2, the color signal C is on the low frequency side, and the luminance signal Y
is recorded by FM transmission on the high frequency side. Furthermore, in television receivers, frequency selection characteristics of video intermediate frequency amplifiers and filter characteristics of IC receivers, I! In the +1 amplifier circuit, a betatal clamp circuit, an AGC circuit, etc. are added.

Further, in the VTR system, FM modulation of a low carrier wave is performed, and nonlinear emphasis is also performed in order to further improve the S/N of the reproduced signal.

For this reason, distortions in the magnetic recording/reproducing system, distortions due to time base errors, and changes in the receiver 4I! ill distortion is added, causing gradual deterioration of image quality.

FIG. 3 is a schematic block diagram illustrating a transmission system for receiving television waves from a broadcasting station at home.

In FIG. 3, when radio waves are transmitted from a television transmitter 1 via a transmitting antenna 2, the broadcast radio waves are received by a color television receiver 4 via a receiving antenna 3.
The image is displayed in color brown v15. The block diagram shown in FIG. 3 is a standard signal transmission system for viewing television at home.

FIG. 4 is a block diagram showing a signal transmission system when a viewer uses a VTR connected to a television receiver at home. In FIG. 4, a radio wave transmitted from a transmitter 1111 via a transmitting antenna 2 is received by a receiving antenna 7 and given to a VTR 6. It includes an air tape 63, a reproducing section 64, and an RF converter 65. RF
The converter 65 frequency-modulates the audio signal reproduced from the VTR 6, amplitude-modulates the video signal, and transmits a radio wave with a minute output. The output of the RF Humbataro 5 is given to the antenna input terminal of the receiver 4.

As mentioned above (in conventional VTRs, the reproduced output signal is once given to the RF converter and then given to the home color television receiver, so the beat generation and RF converter 65
This causes transmission band distortion, and furthermore, the reproduction output of the VTR 6 is transmitted and received again through a complicated transmission path, which deteriorates the characteristics.

[Object of the Invention] Therefore, the main object of the present invention is to provide an image information reproducing device that can obtain color images with good characteristics.

[Summary of the Invention] To summarize the invention, three primary color signals R, G, B signals or Y, RY
, B-Y signals and directly drives a color display device using these three primary color signals.

The above objects and other objects and features of the present invention will become more apparent from the detailed description given below with reference to the drawings.

[Description of Embodiment] FIG. 5 is a schematic block diagram of an embodiment of the present invention.
FIG. 5 is a detailed circuit diagram of the display device shown in FIG. 4, and FIG. 6 is an overall block diagram of an embodiment of the present invention.

First, in FIG. 5, radio waves are transmitted from the transmitter vA1 via the transmitting antenna 2. In FIG. This radio wave is received by the VTR 6 via the receiving antenna 7 and recorded on a magnetic tape. Images recorded on magnetic tape are played back 41 times!
In g1 section 8, it is returned to W4. The output of demodulator 8 is given to display device 16 .

The display device @16 includes an input coupling circuit 9 for receiving the output of the demodulator 8 and displaying it on the cathode ray tube 5. 1. That is, in one embodiment of the present invention, the demodulator 8 is not provided with the RF converter 65 as shown in FIG.
The output from the input coupling circuit 9 is applied directly to the cathode ray tube 5.

Therefore, distortion in the transmission system caused by the RF converter 65 can be removed.

As shown in FIG. 6, the display device 16 receives R, G, B signals or R-Y, B-Y, G-Y,
, Y signals are given. These signals are given to adjust white balance. That is, 3
In many picture tubes using color phosphors, there is a slight difference in the luminous efficiency of the three color phosphors, so it is necessary to perform white balance adjustment to correct this. In the example shown in Fig. 6, the screen voltage of the picture tube is adjusted by controlling the voltage of each of the R, G, and B screens, the cutoff points of the picture tube are aligned, and the voltage of the picture tube is adjusted by adjusting the G drive voltage and the B drive voltage. A method has been adopted in which the voltage is adjusted to compensate for differences in the characteristics of the three electron guns in the picture tube, and to equalize the anode currents.

Referring again to FIG. 5, in the case of two channels as an example, the audio signal accompanying the image is outputted from the demodulator 8 through the amplifiers 10 and 12, respectively, and sent to the respective speakers 1.
Run 1.13. Further, another recording/reproducing signal from the VTR 6 is taken out from the output pin 15 via the amplifier 14.

Further, since a normal VTR also includes a radio wave receiving section 61, it can be used as a normal television receiver and can also record and play back the VTR.

FIG. 7 is a concrete block diagram of an embodiment of the present invention. The block diagram shown in FIG. 7 is the same as a conventional home color television receiver and VTR except for the following points. That is, color television reception 1fi16
The output of the video detector 17 is the VTR playback switch 1.
given to 8. In addition, the output of the VTR 6 is transmitted through the reproduction output attenuator 19 to the VTR? It is applied to the W raw switch 18. Therefore, by changing the VTR playback switch 18 to the receiver side or the VTR side,
The color television receiver 1G can be used as a normal receiver or as a display device for a VTR monitor.

Effects of the Invention As described above, according to the present invention, the R, G, and B signals or the Y, R-Y, and B-Y signals, which are the three primary color signals output from the demodulation circuit of the image information reproducing device, can be directly transmitted. Since it is applied to a color display device, it is possible to prevent deterioration of characteristics such as a transmission band element compared to a device using a conventional RF converter.

[Brief explanation of drawings]

1 and 2 are diagrams showing television signals. FIG. 3 is a schematic block diagram showing a transmission system in a conventional color television receiver. FIG. 4 is a schematic block diagram showing a transmission system when recording and reproducing images with a conventional VTR. FIG. 5 is a schematic block diagram of an embodiment of the present invention. FIG. 6 is a specific circuit diagram of main parts of the display device shown in FIG. 5. FIG. 7 is a detailed diagram of one embodiment of the present invention.
Figure 99. In the figure, 5 is a cathode ray tube, 6 is a demodulating section of the VTR 1B, 9 is an input coupling circuit, 16 is a display device, and 18 is a VTR reproduction switch. Patent applicant Katsura Suzuki 20 + 2 3 44.5MH. Figure 2 1 2 3 4 5 6MH.

Claims (1)

[Claims] In an image information reproducing device that reproduces image information recorded on a recording medium, R, G, and B signals, which are three primary color signals, or Y
, R-Y, B-Y signals; and a color display device directly driven by the three primary color signals.