Question

What will be the value of the Numerical Aperture (NA), if the half aperture angle is 58° and oil-immersed objective is used for the process of light microscopy? (Answer up to 1 decimal place)

Hint:

The Numerical Aperture (NA) is calculated using the formula \( NA = n \times \sin(\theta) \), where \(n\) is the refractive index and \(\theta\) is the half aperture angle.

Answer 1

Correct Answer: 1.2

The formula for the Numerical Aperture (NA) is: \[ NA = n \times \sin(\theta) \] Where:
- \(n = 1.50\) is the refractive index of the immersion oil,
- \(\theta = 58^\circ\) is the half aperture angle.
Substitute the known values: \[ NA = 1.50 \times \sin(58^\circ) = 1.50 \times 0.85 = 1.3 \] Thus, the Numerical Aperture is \(1.3\).