JP2001119606A - Vertical phase controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain requirement for correct scanning that a video signal and a scanning line do not overlap with each other in the case of adjusting a vertical phase by a vertical phase controller that controls the vertical phase, even when an interval of a vertical synchronizing signal differs from fields. SOLUTION: This vertical phase controller, that controls the vertical phase for vertical deflection, is provided with a 1st vertical phase controller, a field detector that detects the interlace scanning and the progressive scanning to invert an output by each 1 V, a pulse generator that delays an output of the field detector by a half vertical period, a 2nd vertical phase controller that uses an output of the pulse generator for a mask pulse to shift the vertical phase of the masked part forward/backward, and a vertical phase control section that controls a phase change of the 1st and 2nd vertical phase controllers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a vertical phase control device for controlling a vertical pulse used for vertical deflection in a television receiver.

[0002]

2. Description of the Related Art In recent years, the input sources of a television receiver have been diversified, and the development of functions and cost reduction of a vertical deflection circuit capable of receiving an image without any problem even in the case of non-standard signals have been emphasized. Hereinafter, a conventional vertical phase adjusting circuit for adjusting the vertical phase will be described.

FIG. 3 is a block diagram showing a vertical phase adjusting circuit proposed in Japanese Patent Application Laid-Open No. 10-13703. In FIG. 3, vertical synchronizing signals input from an input terminal 35 are monomultivibrators 31, 3
Delayed by approximately 2, vertical periods by 2, 33, and 34, and output from the output terminal 36 as a pseudo vertical synchronization signal. With the above configuration, it becomes possible to correctly scan a vertical synchronizing signal such as a field double scan signal in which a vertical synchronizing signal interval differs for each field.

[0004]

However, the above configuration has the following problems. By using four stages of mono-multivibrators, the amount of variation or temperature drift becomes almost four times as large as when using one stage of mono-multivibrators, and the number of unstable elements in the circuit configuration increases. Also, since the input vertical synchronizing signal is delayed by approximately two vertical periods, the vertical phase of the video signal on the display screen and the vertical pulse for vertical deflection are shifted by two vertical periods, so that accurate vertical deflection cannot be performed. .

[0005]

In order to solve the above-mentioned problems, a vertical phase control device for controlling a vertical phase for performing vertical deflection according to the present invention is provided for each vertical synchronizing signal based on vertical and horizontal synchronizing signals. A first vertical phase control device for moving the vertical phase back and forth, a field detection device for performing interlaced and progressive detection, and for an interlaced signal, for detecting whether an even field or an odd field, and an output for each 1 V being High. And a pulse generator that outputs a pulse repeating Low, a second vertical phase control device that moves the vertical phase of a portion not masked by the mask pulse back and forth using the output of the pulse generator as a mask pulse, A vertical phase controller for controlling the amount of phase change of the first and second vertical phase controllers; Those having a structure of pole tip.

[0006]

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a block diagram of a vertical phase control device for controlling a vertical phase for performing vertical deflection according to a first embodiment of the present invention. In FIG. 1, a first vertical phase control device 1 is a control device that moves the phase of a vertical synchronization signal back and forth with reference to an input horizontal synchronization signal and vertical synchronization signal. The field detection device 2 detects the phase relationship between the input horizontal synchronizing signal and vertical synchronizing signal to determine a progressive signal or an interlace signal. In the case of an interlaced signal, a decision is made on an odd field or an even field.
The pulse generator 3 outputs a pulse that repeats High and Low every 1 V based on the determination result of the field detection device 2. The second vertical phase control device 4 is a device that uses the output result of the pulse generator 3 as a mask pulse and controls the phase of the V pulse only during the period when the mask pulse is High. The vertical phase control unit 5 is a block that controls the amount of phase that the first vertical phase control device 1 and the second vertical phase control device 2 change.

The operation of the vertical phase control device for controlling the vertical phase for performing the vertical deflection configured as described above will be described with reference to FIG. FIG. 2 is a waveform diagram of a signal output from each part of the vertical deflection pulse generating circuit for performing vertical deflection according to the present invention.

In FIG. 2, a vertical synchronizing signal A and a horizontal synchronizing signal B are interlaced signals. The first vertical phase control device 1 is a device for moving the vertical synchronization signal A back and forth. In the case of an interlace signal, the vertical synchronizing signal A has a phase relationship with the horizontal synchronizing signal which differs by a half horizontal synchronizing period every vertical period. When the phase of the vertical synchronizing signal A is moved back and forth, it is necessary to move the phase of one horizontal synchronizing signal in order to match the phase relationship between the horizontal and vertical synchronizing signals.

Therefore, when the vertical synchronizing signal is moved forward, the pulse C1 is generated based on the vertical synchronizing signal one vertical period before, and when the vertical synchronizing signal is moved backward, the current vertical synchronizing signal is generated. A pulse C2 is created as a reference.
The field detection device 2 performs field detection.
A High signal is output as a waveform signal D during an odd field period and a Low signal is output as a waveform signal D during an even field period. The pulse generator 3 outputs the output of the field detector 2 to 1
The waveform signal is output as a waveform signal E, which is delayed by a / 2 vertical period. The second vertical phase controller 4 determines that the pulse E is H
This is a device that moves the phase of a pulse forward or backward only during the period of high. For example, this is a case where the waveform F shifts the phase backward. The vertical phase control unit 5 is a block for controlling the amount of phase control of the vertical phase control device 1 and the vertical phase control device 2.

As described in detail above, according to the vertical phase control device for controlling the vertical phase for performing the vertical deflection of the present invention, when the vertical phase is moved forward and backward, the conventional circuit example is used. Such a delay means is not required, and the circuit configuration is simplified. Further, by adjusting the vertical phase back and forth in each vertical period, it is possible to control the interference between the mask pitch of the CRT and the scanning lines, that is, the reduction of moire.

[0012]

As described above, according to the present invention, the first vertical phase control device for moving the vertical phase back and forth for each vertical synchronizing signal based on the vertical and horizontal synchronizing signals, interlace and progressive detection, and In the case of a signal, a field detection device for detecting whether the field is an even field or an odd field, and outputs for each 1 V are High and Lo.
a pulse generator that outputs a pulse repeating w,
A second vertical phase controller that moves the vertical phase of the portion not masked by the mask pulse back and forth using the output of the pulse generator as a mask pulse, and a phase of the first and second vertical phase controllers. By providing the vertical phase control unit for controlling the amount of change, no delay means is required when moving the vertical phase back and forth, and the circuit configuration is simplified. Further, by adjusting the vertical phase back and forth in each vertical period, it is possible to control the interference between the mask pitch of the CRT and the scanning lines, that is, the reduction of moire.

[Brief description of the drawings]

FIG. 1 is a diagram showing a vertical phase control device according to a first embodiment of the present invention.

FIG. 2 is a waveform chart showing the operation of each part in the vertical phase control device of the present invention.

FIG. 3 is a block diagram of a conventional vertical phase adjustment circuit.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 first vertical phase controller 2 field detector 3 pulse generator 4 second vertical phase controller 5 vertical phase controller

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/12 H04N 5/12 Z Inside (72) Inventor Ryuichi Shibuya 1006 Kadoma, Kazuma, Osaka Pref.Matsushita Electric Industrial Co., Ltd. Masahiro Takeshima 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture F-term in Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A vertical phase control device for controlling a vertical phase for performing vertical deflection, comprising: a first vertical phase control device for moving a vertical phase of a vertical synchronization signal back and forth with reference to vertical and horizontal synchronization signals; , An interlace and progressive detection, and furthermore, in the case of an interlace signal, detection of an even field or an odd field, and output of a pulse whose output every 1 V repeats High and Low, and an output of the field detection apparatus. To 1 /
A pulse generator for delaying two vertical cycle periods, a second vertical phase control device for moving the vertical phase of a portion masked by the mask pulse back and forth using the output of the pulse generator as a mask pulse, and And a vertical phase control unit for controlling a phase change amount of the second vertical phase control device. 2. The field detection device detects an even field and an odd field when an input is interlaced and determines the polarity of an output pulse according to the detection result, but enables the polarity to be inverted. 2. The vertical phase control device according to claim 1, wherein when the input is progressive, the output pulse every 1 V repeats High and Low. 3. The first vertical phase control device generates an output pulse based on a vertical pulse one vertical period earlier when moving the vertical phase forward, and generates a current output pulse when moving the vertical phase backward. The output pulse is created based on the vertical pulse of the above, so that even if a vertical synchronization signal having a different number of horizontal lines is input for each vertical period, the vertical deflection and the scanning line of the video signal do not always overlap. The vertical phase control device according to claim 1, wherein: