Home | Links | Contact Us | More About Intellectual Property | Bookmark

Search patents:

Home

Image Analysis

Black-level-clamping-circuit-including-video-output-stage

Decision feedback equalizer with a pattern detector

It is therefore an object of the present invention to eliminate the drawbacks particular to the ...

Data transmission system comprising a decision feedback equalizer and using partial-response techniques

OF THE PREFERRED EMBODIMENT In FIG. 1 a block diagram is shown of a system for data signal ...

Video scanning change discriminator

Referring to the general block diagram of FIG. 1, the combination of the invention is disclosed in ...

Switching network with a crosstalk elimination capability

It is, therefore, an object of the present invention to provide a switching network capable of ...

Cancelling cross modulation in two color TV signals passed through non-linear path

What is claimed is: 1. In a system in which two color television video signals having slightly ...

Read systems for 21/2D coincident current magnetic core memory

In accordance with the invention, bit lines of a two-line 21/2D coincident current magnetic core ...

Magnetic reproducing system for a digital signal

OF THE DRAWINGS FIG. 1 is a system block diagram showing an example of a signal recording system ...

Dual polarization transmission system

It is therefore an object of the present invention to provide a dual polarization transmission ...

Method for clock pulse synchronization

It is the object of the present invention to provide a method of the above-mentioned type which is ...

Tracking filter system for use with a FM/CW radar

What is claimed is: 1. A signal processing system comprising in combination: means receptive of an ...

Black level clamping circuit including video output stage

Details

Inventors: Kanai, Toshio;
Assignee: Matsushita Electric Industrial Co., Ltd. (Osaka, JP)
Primary Examiner: Groody; James J.
Assistant Examiner: Powell; Mark R.
Attorney, Agent or Firm: Wenderoth, Lind & Ponack

A clamping circuit of a high definition CRT display which is adapted to feed the picture signals to the cathode of the cathode-ray tube through a coupling capacitor is connected to the above described cathode, and the above described pulse clamping circuit is operated during the picture blanking period for charging the coupling capacitor so as to change the DC voltage of the cathode. A reference voltage source which conforms to the electrical potential of the black level of the above described picture signal is provided, the above described reference voltage source is connected to the picture signal output line during the picture blanking period so as to reduce the output impedance of the picture output circuit during the same period to correctly reproduce the brightness in spite of the picture signals.

DETAILED DESCRIPTION Accordingly, the present invention has been developed with a view to substantially eliminating the above discussed drawbacks inherent in the prior art, and has for its essential object to provide an improved black level clamping circuit.
Another important object of the present invention is to provide a clamping circuit, which is adapted to reduce the variations in the DC voltage between the black signal and the white signal so as to correctly reproduce the brightness.
The brightness circuit of the present invention is provided with a means which is adapted to make the output impedance of the picture output circuit smaller for a period of picture blanking pulses only to be fed to the keyed clamping circuit.
In the clamping circuit of the present invention of such construction as described hereinabove, the charging time constant of the coupling capacitor is made much smaller as compared with the discharging time constant to remove the influences of the discharging operation for correctly effecting the DC voltage shift, thus resulting in the correct reproduction of the brightness.

Related patents

	Equalizer for the correction of digital signals I claim: 1. An equalizer for eliminating the effects of postcursor and precursor interference from a periodically sampled train of incoming digital signals, comprising: ...
	Phase jitter compensation arrangement using an adaptive IIR filter In the transmitter section (not shown) of a modem, digital bits representative of information to be transmitted are received from a digital device, e.g., a terminal, in ...
	Adjacent channel interference canceller with means for minimizing intersymbol interference What is claimed is: 1. A device for use in processing a device input signal carrying a digital symbol sequence to produce a device output signal, said device comprising ...
	Phase adjustment circuit What is claimed is: 1. A phase adjustment circuit comprising: an input terminal for inputting a synchronizing signal thereto; an integration circuit having an input side ...
	Receiver interference suppression system Accordingly, it is an object of the present invention to provide an improved radio receiver which utilizes a simple, effective, and inexpensive solution to the problem ...
	Apparatus for encoding television signals of different formats for transmission and decoding upon reception I claim: 1. Apparatus for generating a time multiplexed signal for transmission over a single channel having an assigned channel bandwidth, comprising: receiving means ...
	Method and apparatus for digitally processing gamma pedestal and gain What is claimed is: 1. A method of processing video signals, comprising: reading video signals; providing in a memory data for correcting gamma, black level and white ...
	Selectively enabled image signal processing circuit using recursive filtering The present invention was made in view of the above facts, and an object of the present invention is to provide an image signal processing circuit by which the problems ...
	Carrier chrominance signal processing circuit Accordingly, a general object of the present invention is to provide a novel and useful carrier signal processing circuit in which the above disadvantages are eliminated....
	White balance correcting device Accordingly, the present invention has an object to provide a white balance correcting device for use in a color video camera, which can eliminate the disadvantages ...

0.024
Archive: All patents - Links Copyright (c)2006 Eipa-patents.org - All rights reserved