Image display apparatus and image display methods

Abstract

Provided are image display apparatus and image display methods capable of suitably making correction for variation of driving conditions due to an electric resistance of matrix wiring of a display panel by downsized hardware. The apparatus and methods involve a device of calculating voltage drop amounts caused by the resistance of row wires, for input image data, and a device of calculating image data with correction for the voltage drop amounts (corrected image data). An overflow processing circuit is provided so as to prevent overflow of the image data after the correction from an input range of a modulator, and the overflow is prevented by a gain. Since a gradation converter for changing a gradation conversion characteristic by a gain is provided in the stage preceding to the configuration for making the correction for influence of the voltage drop, it becomes feasible to cancel saturation characteristics of phosphors and to display images with high quality thereby.

1 .- 19 . (canceled) 
   
   
       20 . An image display apparatus comprising:
 a plurality of first wirings to which a selection potential is applied;   a plurality of second wirings to which a modulation signal is supplied;   electron-emitting devices connected to the first and second wirings;   a phosphor emitting light in response to an irradiation with an electron emitted from the electron-emitting devices;   a modulating circuit for supplying a modulation signal to the second wirings;   a conversion circuit for converting an image data in response to a nonlinear characteristic of the phosphor; and   a multiplier circuit for multiplying an image data by a gain, the gain having a value for at least partially preventing image data having a value beyond an input range of the modulating circuit from being input to the modulating circuit,   wherein the conversion circuit performs conversion corresponding to the gain.   
   
   
       21 . An image display apparatus according to  claim 20 , wherein
 the conversion circuit comprises a multiplier circuit for multiplying input data by the gain.   
   
   
       22 . An image display apparatus according to  claim 20 , wherein
 the conversion circuit has correction tables capable of outputting respectively different conversion values correspondingly to gains of plural values for one input data.   
   
   
       23 . An image display apparatus according to  claim 22 , wherein
 the conversion circuit outputs a conversion value in an interpolation manner.   
   
   
       24 . An image display apparatus according to  claim 20 , further comprising
 a correction circuit for outputting an image data which is corrected with a correction data for correcting a loss, wherein said gain is determined by the corrected image data.   
   
   
       25 . An image display apparatus according to  claim 20 , further comprising
 a determination circuit for determining the gain based on a value of the data inputted from the converting circuit.   
   
   
       26 . An image display apparatus according to  claim 24 , wherein said multiplier circuit multiplies the image data which is corrected by the correction circuit by the gain. 
   
   
       27 . An image display apparatus according to  claim 24 , wherein said multiplier circuit multiplies the image data which is not corrected by the correction circuit by the gain. 
   
   
       28 . An image display apparatus according to  claim 20 , further comprising a limiter for limiting the value of image data so as to prevent the image data having a value beyond the input range of the modulating means from being inputted to the modulating circuit.