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In this paper, we'll journey through the evolution of display technologies, delving into the
intricacies of how our eyes perceive motion and the challenges that modern displays
have brought to the forefront when it comes to motion blur and judder.
2.0 The Evolution and Legacy of Film Projectors, CRT, and Plasma
Displays
2.1 Film Projectors
Film projectors, long the stalwarts of cinemas, operate on a mechanical principle. Films
are essentially a sequence of static images, and the projector displays these images
one after the other at a rapid pace, typically 24 frames per second (fps). The rotating
shutter of a projector blocks light intermittently, ensuring that there is a brief dark period
between each frame. In order to avoid flickering, film projectors usually show each
frame two or three times.
Motion Handling in Film Projectors: The intermittent darkness introduced by the rotating
shutter represents a non-sample-and-hold approach, allowing our brain to merge these
rapidly shown images into a seamless-looking moving picture. The resulting clean and
sharp motion has a unique characteristic, often dubbed the "film look," which is distinct
from the look of video content rendered on sample-and-hold type displays.
These legacy display technologies, although replaced in popularity, have set
foundational standards in motion presentation, leading to current expectations and
challenges as technology progressed.
2.2 Cathode Ray Tube (CRT)
The CRT was the quintessential television and computer display type for much of the
20th century. Comprising a large vacuum tube with an electron gun at one end and a
phosphorescent screen at the other, CRTs created images by firing electrons at the
screen. The rapid and continual scanning of electron beams, line-by-line, illuminated
specific phosphors on the screen to create a full image.
Motion Handling in CRTs: CRTs inherently avoided motion blur because the phosphors
would only briefly glow after being hit by the electron beam, fading quickly before the
next frame began. This "fading" meant that at any given moment, only a small portion of
the screen emitted light, which coincidentally worked well with the persistence of vision
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