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In the meantime, it is helpful to understand how various display technologies work,
specifically considering their strengths and weaknesses in the context of 24-fps
content. These technical details help explain why they are subject to artifacts from
sample-and-hold.
3.1 OLED (Organic Light-Emitting Diode) Displays
OLED technology, characterized by its self-emissive nature, can turn individual pixels on
and off. This results in incredible black levels and contrast ratios. Being a
sample-and-hold technology, each frame in an OLED display is continuously displayed
until the next frame replaces it.
3.2 LCD (Liquid Crystal Display)
LCDs operate by using a backlight to shine through liquid crystal cells, which act as
shutters to create the image. Just like OLEDs, LCDs also use the sample-and-hold
method, resulting in added motion blur and possible judder.
3.3 LCD and LCoS Projection
LCD and LCoS projectors have a light source which is then split into red, green and blue
light spectrums, which are run through three separate LCD/LCoS panels (one for each
primary color), and then merged for final output. Since the LCD/LCoS panels operate in
a sample-and-hold manner, the same motion problems discussed previously are usually
introduced.
3.5 DLP (Digital Light Processing) Projection
DLP projectors utilize tiny mirrors laid out in a matrix on a semiconductor chip, known
as Digital Micromirror Device (DMD). Each mirror corresponds to a pixel and can tilt to
reflect light towards or away from the projection surface. DLPs use Pulse Width
Modulation (PWM) to create different intensities of different colors, which is to some
extent similar to how Plasma displays worked.
Although DLP can largely avoid the sample-and-hold artifacts commonly seen in most
other modern display technologies, it is not without its own quirks. For example, the use
of temporal dithering to create images can introduce a different set of motion artifacts.
Thus, while DLP's motion handling is generally better than sample-and-hold methods, it
does not perfectly replicate the experience of film projection.
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