| 摘要 |
Reflective or (area-division type) transflective display (1) illuminated obliquely from the front, which exhibits a uniform image brightness at a desired viewing position.
In reflective display devices, the display reflectance for a given viewing position (angle) may be enhanced by arranging the pixel (12) reflectance characteristics to have a fixed predetermined angular dependence, e.g. by using an anisotropic scattering film (14). This is done to compensate for the effect of reduced reflectance with colour (wavelength) or to prevent the image being viewed outside a given viewing position (angle range). However, it does lead to a lack of image brightness uniformity, even when all the pixels are displaying the same gray level, especially if a conventional front-light is used.
According to this disclosure, the intensity distribution of the front light source (30) is tailored (either individually by adjusting source intensities (31) or collectively by employing an intervening optical elements, such a s a neutral density filter having a transmission distribution (132)) to compensate for the reflectance properties of the pixels and so to achieve a uniform image brightness luminosity at the desired viewing position. |
