US 6,144,354 AGranted

Image display apparatus

AssigneeSeiko Epson Corporation

InventorsFumio Koyama, Keijiro Naito, Kiyoshi Miyashita

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Abstract

To provide an image display apparatus in which, even if pixel data is phase-expanded, the influence of differences in circuit characteristic can be dispersed between frames. The apparatus has a phase expansion circuit 380 to which are input a first video signal A1 having pixel data for driving pixels with positive voltages and a second video signal A2 having pixel data for driving pixels with negative voltages. The phase expansion circuit 380 forms six phase-expanded signals V1 to V6 from the first and second video signals A1 and A2. The phase-expanded signals are expanded into pixel data by extending the data length of items of the pixel data corresponding to some of the pixels periodically selected. The phase expansion circuit 380 outputs the phase-expanded signals to phase-expanded signal output lines in parallel with each other. The apparatus also has a connection change circuit 390 for changing connections between six phase-expanded signal output lines 388a to 388f and six signal supply lines 132a to 132f. Change of the order of expansion into six phase-expanded signals V1 to V6 by the phase expansion means and change of the combination of connections changed by the connection change circuit 390 while being linked to the expansion order are controlled by a timing generation circuit block 200. This timing generation circuit block 220 performs change control so that a expansion order first set with respect to the preceding frame is changed to a different expansion order in synchronization with vertical synchronization.

Claims14

Dependent claims

An image display apparatus having:

an image display unit in which pixels electrically connected to a plurality of data signal lines and to a plurality of scanning signal lines are arrayed in a matrix form;
and
scanning signal line selection means for supplying said scanning signal lines with scanning signals for successively selecting said scanning signal lines,
said apparatus driving said pixels by applying voltages to the pixels in accordance with said data signals and said scanning signals while inverting the polarities of the voltages applied to the pixels, said apparatus comprising:
phase expansion means supplied with a first video signal having serial pixel data for driving said pixels by voltages having a first polarity, and with a second video signal having serial pixel data for driving said pixels by voltages having a second polarity, said phase expansion means forming, from said first and second video signals, m (where m is an integer equal to or larger than 2) phase-expanded signals expanded into pixel data by extending the data length of items of said pixel data corresponding to some of said pixels periodically selected, said phase expansion means outputting the phase-expanded signals to phase-expanded signal output lines in parallel with each other, wherein said phase expansion means has m sample and hold sections connected to said m phase-expanded signal output lines, said first video signal being constantly input to one of two groups of said sample and hold sections during a frame period, said second video signal being constantly input to the other group of said sample and hold sections during the frame period;
signal supply means for supplying said pixel data to said plurality of data lines on the basis of said m phase-expanded signals input via m signal supply lines;
connection change means for changing connections between said m phase-expanded signal output lines and said m signal supply lines;
and
change control means for controlling change of the order of expansion into said in phase-expanded signals performed by said phase expansion means, and a combination of connections changed by said connection change means by linking the combination to said expansion order,
wherein said change control means performs change control so that an expansion order first set with respect to the preceding frame is changed to a different expansion order in synchronization with vertical synchronization.

7 more elements

An image display apparatus having:

an image display unit in which pixels electrically connected to a plurality of data signal lines and to a plurality of scanning signal lines are arrayed in a matrix form;
scanning signal line selection means for supplying said scanning signal lines with scanning signals for successively selecting said scanning signal lines;
and
signal supply means for supplying pixel data signals to said plurality of data signal lines,
said apparatus driving said pixels by applying voltages to the pixels in accordance with said data signals and said scanning signals while inverting the polarities of the voltages applied to the pixels, said apparatus comprising:
first phase expansion means supplied with a digital signal having pixel data of a first data length corresponding to the position of each of said pixels, said first phase expansion means outputting two phase-expanded digital signals in which items of said pixel data corresponding to some of said pixels periodically selected are expanded into pixel data having a data length n (where n is an integer equal to or larger than 2) times longer than said first data length;
first and second branching means respectively supplied with said phase-expanded digital signals, each of said first and second branching means branching a route for the phase-expanded digital signal into a first route on which the polarity of the digital signal is not inverted and a second route on which the polarity of the digital signal is inverted by polarity inversion means;
first selection means for selecting one of said first and second routes branched by said first branching means;
second selection means for selecting one of said first and second routes branched by said second branching means;
and
first and second digital-to-analog conversion means for respectively analog-to-digital converting the two phase-expanded digital signals selected by said first and second selection means to output two first phase-expanded analog signals,
wherein said signal supply means supplies said pixel data signals to said data signal lines on the basis of said two first phase-expanded analog signals.

9 more elements

An image display apparatus having:

an image display unit in which pixels electrically connected to a plurality of data signal lines and to a plurality of scanning signal lines are arrayed in a matrix form;
scanning signal line selection means for supplying said scanning signal lines with scanning signals for successively selecting said scanning signal lines;
and
signal supply means for supplying pixel data signals to said plurality of data signal lines,
said apparatus driving said pixels by applying voltages to the pixels in accordance with said data signals and said scanning signals while inverting the polarities of the voltages applied to the pixels, said apparatus comprising:
first phase expansion means supplied with a digital signal having pixel data of a first data length corresponding to the position of each of said pixels, said first phase expansion means outputting two phase-expanded digital signals in which items of said pixel data corresponding to some of said pixels periodically selected are expanded into pixel data having a data length n (where n is an integer equal to or larger than 2) times longer than said first data length;
polarity determination means supplied with said two phase-expanded digital signals, said polarity determination means determining the polarities of said two phase-expanded digital signals by leading one of said phase-expanded digital signals to a first route on which the polarity of the digital signal is not inverted and leading the other of said phase-expanded digital signals to a second route on which the polarity of the digital signal is inverted by polarity inversion means;
first and second digital-to-analog conversion means for respectively analog-to-digital converting said two phase-expanded digital signals having the determined polarities to output two first phase-expanded analog signals,
wherein said signal supply means supplies said pixel data signals to said data signal lines on the basis of said two first phase-expanded analog signals.

6 more elements

Dependencies are inferred from the claim text.