flexyPage explains Display Features
- 2. Resolution The resolution of a display is the product of the amount of portrayable pixels in the horizontal (a) and vertical (b) direction (pixels horizontal x pixels vertical = resolution). For example, if we have 1200 pixel in the horizontal direction and 700 pixel in the vertical direction, we would talk about a resolution of 1200 x 700, or 840 000 pixels. To make it simple, we can say that the higher the resolution the better the portrayable image.
- 3. DPI DPI or "dots per inch" is a measurement of pixel density.This unit represents how many dots will be printed in an area of 2,54 centimeters. In case of displays we technically talk about PPI or "pixel per inch". However, people still mention DPI when talking about displays. If the pixel density is reduced the picture looks increasingly grainy. To illustrate the effects of a reduced pixel density we incorporated the following flexyPage logo from high to low pixel density.
- 4. Angle The angle is the perspective with which the display is viewed. In the day to day displays are viewed from the side or from below. People are not equally tall, nor can they always freely choose the point at which they stand in a lift. This means it is necessary for the display to have a perfect view from the left, the right, from above and from below, since lift displays are mostly attached above the doors or in the edges.The displays needed for this kind of work are displays who have a great viewing angle, that means they do not have a loss of brightness or contrast.
- 5. Colors The amount of gradation in a color channel is measured in bits, with one bit equivalent to two gradations. The higher the gradation the more degrees of brightness can be represented on the display. In Liquid Crystal Displays (LCD) and Active-Matrix-Displays (TFT) brightness is determined by the light source behind the liquid crystal. The light source is usually a LED light or CFL tubes. If the lights are brighter, the display will be brighter. Brightness in displays is indicated in Cd/m2. Typical values that are achieved range from 350 to 400 Cd/m2 in the office. Outside, with Digital Signage or in lifts with direct sunlight exposure, brightness of 1000-1300 Cd/m2 is necessary to see everything on the display.
- 6. Technology LCD displays contain liquid crystals with a light source behind them. If a current is applied the crystals turn and by doing so control the kind of lightwaves that can pass through. This way, an image is created on the display. LCD are distinguished by the arrangement of the pixel (Twisted Nematic, Vertical Alignment and In-Plane Switching), the background lighting, triggering of the pixels (Passive Matrix or Active Matrix) and the pixel material. no current - polarized light passes the 90° turned liquid crystals and the display appears white. voltage - the liquid crystals turn and change the polarization of the light no current - the liquid crystals are aligned vertically and the display is black if. voltage - the crystals change their alignment and light from the background go through. Displays with IPS have a good viewing angle, a fast reaction time and a good representation of colors. They use though much more energy and are more expensive to produce. OLED consist of ultra-thin organic layers, that emit light when voltage is applied. OLED displays don't need background lighting and therefore possess an extraordinary good contrast. Twisted Nematic Vertical Alignment In-Plane Switching Organic Light Emitting Diodes
- 7. Anti-Aliasing Since pixels are coloured squares, a line that is not completely aligned to the pixels (horizontal or vertical) will appear 'jagged' - as in our image. As it is, this line looks more like a staircase. Anti- aliasing exists to eliminate this problem. With anti-aliasing similar- coloured pixels are added between the "steps" of the staircase. After adding the pixels the image looks better and smoother to the human eye from a certain distance. Anti-aliasing is also used for type fonts. In the following we will show you the letter A on a white display. The left image is with anti-aliasing, the right one is without anti-aliasing.
- 8. What is flexyPage? flexyPage is a modern, flexible system for multimedia presentation of process and multimedia data on displays of different sizes and construction types. Because its powerful multicore processors, common in smartphones no active cooling is necessary. This way, it is possible to realize very small housing dimensions. Therefore the flexyPage system is ideally suited for use in lifts, in 'Digital Signage'-applications, in building automation, as well as in mechanical engineering.