Is it a fad or is there a real advantage to using a widescreen format for an HMI device?
The increased use of the PC as a multimedia device in the consumer area has ultimately resulted in the replacement of 4:3 displays with a widescreen format. However, movies in production could hardly be considered an HMI device application relevant for decision making.
The fact is that an operating screen has to fulfill two tasks which are partly in competition with one another.
Buttons are preferably located in the margin of a screen, often as control bars or menu bars. This is practically mandatory if the function keys of a keypad device are to be used.
And this may be the primary benefit of the widescreen format: Compared to the classic 4:3 format, it offers more of the urgently needed "marginal areas", which means space for one or two more function keys below the screen with a direct link to it. (See Fig. below).
Fig. Arrangement of the function keys on the OP 277 and KP700 Comfort
(the four yellow keys of the OP277 have no link to the screen)
Fig. Comparison of the display area of TP 277 and TP700 Comfort. Blue indicates the additional "marginal area" (not taking into consideration the higher screen resolution of the TP700)
The displays must have a higher resolution, even for smaller devices, so that the production process can be visualized clearly and in sufficient detail. A TP700 Comfort with its 7" display offers a significantly higher resolution than a 10" SIMATIC Panel PC 670 from 2004 and requires only as much space as a TP 277 with a 6" screen thanks to its modern, frameless design.