| 摘要 |
PURPOSE:To quantitatively and automatically decide the picture quality of a liquid crystal cell by displaying a white raster on the liquid crystal cell, executing the image-pickup of such a display picture, obtaining the histogram of luminance distribution in picture data, which are obtained by this image-pickup, and checking the picture quality from the condition of this distribution. CONSTITUTION:A picture signal is received from a CCD camera 8, converted to the picture data and stored in a picture memory 14 as the picture data in a picture processor 11. Then, a distribution checking part 15 reads the luminance level of respective picture elements from the picture data, which are stored in the picture memory 14, and prepares the histogram of the luminance distribution. When a liquid crystal cell 4 has satisfactory quality not to have unevenness in a picture, for the histogram of the luminance distribution, the distribution approaches Gaussian distribution. Accordingly, a cross-correlation value is obtained for a normal distribution function and the histogram of the luminance distribution and the propriety of the picture quality can be decided from these values and a propriety deciding value. Thus, picture quality and the like, can be quantitatively and automatically checked. |
