Enter the radius of curvature (mm) into the Focal Distance Calculator. The calculator will evaluate and display the Focal Distance.
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Focal Distance Formula
The following formula is used to calculate the Focal Distance.
FD = R / 2
- Where FD is the Focus Distance (mm)
- R is the radius of curvature (mm)
How to Calculate Focal Distance?
The following example problems outline how to calculate Focal Distance.
Example Problem #1:
- First, determine the radius of curvature (mm).
- The radius of curvature (mm) is given as: 55.
- Finally, calculate the Focal Distance using the equation above:
FD = R / 2
The values given above are inserted into the equation below and the solution is calculated:
FD = 55 / 2 = 27.5 (mm)
Example Problem #2:
For this problem, the variables needed are provided below:
radius of curvature (mm) = 89
${V2} = ${number 4}
This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer.
FD = R / 2 = ?
