[visionlist] Re: CRT Vs LCD

[Andrew Watson]

Just to add one small point to the discussion of the speed of LCD displays.

The response in time of an LCD pixel differs in two ways from that of a 
CRT. The first is that the LCD may be slow to switch from off to on, but 
the second and more significant difference is that the LCD remains on 
for the duration of the frame (it is a "hold-type" display). This causes 
"motion blur" as the eye tracks a moving target, and will do so even if 
the switching time is reduced to zero. There are many techniques now 
being developed (and sold) to ameliorate this problem, among them "black 
insertion" (essentially reducing the hold time), 120 Hz frame rate with 
motion interpolation, and strobing and scanning backlights (which can in 
principle make the LCD into a sample-type display).

All of these techniques show promise but carry with them trade-offs and 
potential artifacts. It will be interesting to see which, if any, 
produce displays that are suitable for vision research with rapidly 
moving images. I hope folks will share their experiences.

-Beau