Patent ID: 7339557
Filing Date: 2008-03-04
Classification: G09G

Abstract:
1. A display apparatus comprising: a display unit having a matrix of multiple pixels; a divider to divide each of a plurality of fields of a digital input video signal into N number of subfields each subfield having a period shorter than a period of each field, N being a positive integer of two or larger; a memory storing a look-up table to be used by the divider for dividing the field into the subfields, the look-up table listing data for selectively turning on and off the subfields in accordance with gradation levels of the digital video signal, an image being displayed on the display unit when the subfields are selectively turned on; and a driver to drive the pixels of the display unit per N number of subfields so that an image based on the digital input video signal is displayed on the display unit, wherein the data are arranged in the look-up table such that the N number of subfields are aligned from a first subfield to an N-th subfield in an image-displaying order, display periods of the subfields become longer from the first subfield towards the N-th subfield or from the N-th subfield towards the first subfield, a difference in display period between subfields adiacent to each other becomes smaller per at least one subfield as the display periods become longer, for specific gradation levels at which false contour effects have to be restricted, a specific subfield to be turned on is shifted by one subfield in the image-displaying order, or the specific subfield is kept on when the specific subfield is once turned on and one of subfields having shorter display periods than the specific subfield is turned on, per gradation-level change, for gradation levels except the specific gradation levels, a subfield to be turned on is shifted by at least one subfield in the image-displaying order, per gradation-level change, and wherein when a subfield having the longest display period among the N number of subfields is turned from off to on at a certain gradation level, the subfield thus turned on is kept on at gradation levels higher than the certain gradation levels.