Display contrast

Abstract: Study I investigated the effects of display type, amount of information presented, and display contrast on the visual mechanism during a visual search task. In the first phase, two subjects performed the visual task for four 3-h sessions. In the second phase, subjects were tested for two 6-h sessions. CRT usage for 3 h produced measurable visual fatigue in the eye movement and/or accommodation mechanism, as measured by increased durations to move from a near point and focus on a far point (and vice versa). Such visual fatigue was not present in the hard-copy visual search task.In a second study, subjects performed the visual task for two 4-h sessions. Two h of CRT usage produced measurable fatigue in the eye accommodation mechanism as well as an increased blink rate. Such visual fatigue was also present in the hard-copy task but to a lesser extent.In both studies, I-h breaks produced a marked reduction in visual fatigue indices.

Abstract: A method and apparatus improves the visibility of information displayed on a portable electronic device display (142) in various ambient lighting conditions. The portable electronic device (100) measures the ambient light associated with the display (142) and adjusts the display (142) based on the measured ambient light to improve the visibility of the displayed information. In an exemplary embodiment, light detection electronics (110) detect the ambient light associated with the display (142). A light processor (114) processes the raw data to determine the measured ambient light based on the detected ambient light. A display controller (150) of the portable electronic device (100) adjusts the display (142) based on the measured ambient light. An exemplary display controller (150) may adjust the size of the displayed information, a backlight intensity of the display (142), or a display contrast based on the measured ambient light.

Abstract: PROBLEM TO BE SOLVED: To obtain a frontlight type illuminator suppressing deterioration of display contrast, a touch panel with illumination and a reflective liquid crystal display device incorporating them. SOLUTION: A frontlight type illuminator 100, which is arranged on the front side of a liquid crystal display device 200, is equipped with a light guide plate 1, a plurality of light emitting layers 5 which is provided on one plane, placed opposite to the other plane confronted with the liquid crystal display device 200, of the light guide plate 1 and emits a light to illuminate the liquid crystal display device 200 when illuminated with a light, a lightproof layer 6 which is provided so as to cover the front surface of the light emitting layers 5 and shade a light outgoing toward the front surface side of the light emitting layers 5 and a line light source 2 which is provided on an end face of the light transmission plate 1 and irradiates light to excite the light emitting layers 5 and make them emit a light. Thereby it is possible to uniformly illuminate even a large area liquid crystal display device with fine display contrast or the like.

Abstract: A contrast controller for a liquid-crystal display maximizes the display contrast by using a light sensor to detect ambient light levels and light blocked by the LCD panel. The display contrast is maximized by maximizing the difference between the ambient and blocked light levels. Further contrast maximization is accomplished through variable control of the LCD backlight in accordance with sensed light levels.