Optical Engineering Tool

USAF 1951 Resolution Calculator

Select the smallest pattern that still shows three separate bars.

InputEnter the target reading

Group (G)

–

Element (E)

Selected pattern4–4

Target scaleStandard target = 1×

ResultGroup 4 · Element 4

Limiting resolution

22.627lp/mm

One line pair every 44.194 µm

Line-pair pitch44.194 µm

Single bar width22.097 µm

Line density45.255 lines/mm

Current group valuesClick an element

R = 2^{G + (E − 1) / 6} 2^(4 + (4 − 1) / 6) ÷ 1 = 22.627 lp/mm

Group 4 · Element 4 · Standard scale