Elink’s screen is completely different from traditional calculators. Elink uses electronic ink technology, which only consumes power during the process of changing the screen display. After the change, it consumes no power at all. Traditional calculators are not allowed. They must be turned off, otherwise they will consume a lot of battery.
The resolution of e-ink screens is also very high. Ordinary 5-inch and 6-inch screens can reach a resolution of 800X600, while a larger 9.7-inch screen can reach a resolution of 1200X824. The traditional calculator is quite grainy and can display simple numbers, but it is definitely not suitable for displaying text for long-term reading.
To sum up, there is a certain reason why Elink screens are expensive. I don’t have much contact with PDAs, so I believe they are not the same thing as e-ink screens. Moreover, I remember that most PDA screens are very small, only about three or four inches.