1. What is the Diffraction Limit?

The diffraction limit describes the fundamental resolution limit of optical systems due to the wave nature of light. It determines the smallest detail that can be resolved by an optical instrument such as a telescope or microscope.

2. How Does the Calculator Work?

The calculator uses the diffraction limit formula:

Where:

• \( 1.22 \) — Constant derived from the first zero of the Airy disk
• \( \text{Wavelength} \) — Wavelength of light in nanometers (nm)
• \( \text{Aperture} \) — Diameter of the optical aperture in millimeters (mm)

Explanation: The formula calculates the angular resolution limit in radians, where smaller values indicate better resolution capabilities.

3. Importance of Diffraction Limit Calculation

Details: Understanding the diffraction limit is crucial for optical system design, astronomy, microscopy, and photography. It helps determine the maximum achievable resolution for a given optical setup.

4. Using the Calculator

Tips: Enter wavelength in nanometers and aperture diameter in millimeters. Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is the physical meaning of the diffraction limit?
A: The diffraction limit represents the smallest angular separation at which two point sources can be distinguished as separate entities due to the wave nature of light.

Q2: How does aperture size affect the diffraction limit?
A: Larger apertures result in smaller diffraction limits (better resolution), while smaller apertures produce larger diffraction limits (poorer resolution).

Q3: What wavelength should I use for visible light calculations?
A: For general visible light applications, a wavelength of 550 nm (green light) is commonly used as it represents the peak sensitivity of the human eye.

Q4: Can the diffraction limit be overcome?
A: In conventional optics, the diffraction limit is fundamental. However, techniques like super-resolution microscopy can overcome this limit using specialized methods.

Q5: How is the diffraction limit related to numerical aperture?
A: For microscope objectives, the diffraction limit is often expressed as d = λ/(2NA), where NA is the numerical aperture, providing the minimum resolvable distance.