Focal Length of Concave Lens given Radius Calculator

Formula

The formula to calculate the Focal Length of Concave Lens given Radius is:

\[ f_{\text{concave lens}} = \frac{r_{\text{curve}}}{n - 1} \]

Where:

\(f_{\text{concave lens}}\) is the Focal Length of Concave Lens (m)
\(r_{\text{curve}}\) is the Radius (m)
\(n\) is the Refractive Index

Definition

The Focal Length of Concave Lens is the distance between the center of the lens and the focal point, where parallel rays of light converge after passing through the lens.

Example Calculation

Let's assume the following values:

Radius (\(r_{\text{curve}}\)) = 0.068 m
Refractive Index (\(n\)) = 1.28

Using the formula:

\[ f_{\text{concave lens}} = \frac{0.068}{1.28 - 1} \]

Evaluating:

\[ f_{\text{concave lens}} = 0.242857142857143 \text{ m} \]

The Focal Length of Concave Lens is 0.242857142857143 m.

Conversion Chart

Radius (m)	Refractive Index	Focal Length of Concave Lens (m)
0.05	1.28	0.178571428571
0.06	1.28	0.214285714286
0.07	1.28	0.250000000000
0.08	1.28	0.285714285714
0.09	1.28	0.321428571429
0.1	1.28	0.357142857143