A percentage measuring how much of the total measured field intensity at the accessory surface is concentrated within the therapeutic core (scan points where Gauss is at or above 50% of peak). It's calculated as the sum of Gauss values at core points divided by the total sum of all measured Gauss values within the coil boundary. This is a surface concentration metric. It measures lateral field distribution across the face of the accessory, not depth penetration. A high score (70%+) indicates the field is tightly focused in a narrow zone, typical of tight pancake coils. Donut and ring coils vary widely (40–70%) depending on how broad the ring zone is. Loop coils vary by turn count and diameter. The formula is geometry-independent, so the same calculation applies to all coil types. Compare scores within the same coil type for meaningful benchmarks.
Also known as: Flux Concentration
Concentration score asks how much of the field lands in its strongest zone. The gauge on the left is that score as a percentage, the same gauge the report shows. On the right is the field it measures: the core is the region at or above half the peak strength, and the score is the share of the field inside it. A tightly focused coil puts most of its field in the core and scores high; a broad coil spreads it out and scores lower. It describes focus at the surface, not depth.
