Line focus principle (illustration)

Case contributed by Lachlan McKay
Diagnosis not applicable
Diagram

Diagram demonstrating the relationship between the anode angle (theta), the actual focal spot and the effective focal spot.

This relationship may be described by the line focus principle, where

  • sin θ = effective focal spot / actual focal spot 1

Original illustration by Lachlan McKay.

Case Discussion

The line focus principle describes the relationship between the actual focal spot size and the effective focal spot size, as influenced by the anode angle 1.

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