Pulse width modulation
Dithering is spatial (as opposed to temporal) PWM variously used by PDP manufactures to generate colour shades. Panasonic panels use relatively little dithering producing beautifully clean & natural looking, even serene, pictures from properly adjusted panels in appropriate environments. A consequence, however, is the banding in subtle gradients on their consumer products built-down to a price. Nevertheless, shops are typically poor places to accurately audition TVs & monitors and the VT range is probably the best (if flawed) consumer display available. (I'm unaware of any HD CRT that big, but If available it likely would be quite bulky and expensive.)