In raster-scan display systems, which artifact is primarily eliminated when compared to early vector or random-scan systems, in terms of refresh behavior and update performance?

Introduction / Context:
Display technologies historically evolved from random-scan (vector) to raster-scan systems. The question probes understanding of how rasterization and periodic refresh alter perceived flicker and drawing latency compared with stroke-by-stroke vector refresh.

Given Data / Assumptions:

• Random-scan systems draw lines by steering the electron beam along vectors.
• Complex scenes require many strokes, increasing time between redraws for any element.
• Raster systems refresh the entire screen at a fixed rate, typically many times per second.

Concept / Approach:
Flicker arises when refresh of a given element is too infrequent. Slow updates occur when the system must retrace many vectors to redraw a frame. Raster scanning uses a frame buffer and constant-rate scan-out, which stabilizes brightness and reduces flicker while also avoiding per-vector redrawing delays.

Step-by-Step Solution:

Verification / Alternative check:
Contemporary displays use fixed refresh rates and double buffering to keep luminance steady and updates smooth, confirming reduction in flicker and delay.

Why Other Options Are Wrong:

• slow update only: ignores the major flicker reduction due to constant refresh.
• flicker only: understates improvements in update performance from the frame buffer model.
• has no effect: contradicted by practical and historical evidence.
• None of the above: incorrect because both artifacts are mitigated.

Common Pitfalls:
Confusing raster refresh with low refresh rate scenarios, overlooking double buffering, and assuming vector systems scale linearly with scene complexity without visual penalties.

Final Answer:
flicker and slow update