Sharp EL-9650 Equation Editor - This one fom 2001

[xerxes]

I remember this device as disappointing while testing it. It's pretty slow for it's time and even slower than the EL-9300 or EL-9400.
As you mentioned, the readability of the LCD is weak under not optimal light conditions, especially compared to some much older CASIO
devices with touch screen, like the TC-50 wrist watch from 1983, the PB-1000 pocket computer from 1986 or the IF-8000 organizer from
1986 with a full resolution touch screen for drawing graphics.