1. What is Gaussian Beam Divergence?

Gaussian beam divergence describes the angular spread of a laser beam as it propagates. It's a fundamental parameter in laser optics that affects beam quality and focusing characteristics.

2. How Does the Calculator Work?

The calculator uses the Gaussian beam divergence equation:

Where:

• \( \theta \) — Beam divergence angle (radians)
• \( \lambda \) — Wavelength of the laser light (meters)
• \( w_0 \) — Beam waist radius (meters)

Explanation: The equation shows that divergence is directly proportional to wavelength and inversely proportional to the beam waist size.

3. Importance of Beam Divergence Calculation

Details: Understanding beam divergence is crucial for laser system design, optical communications, laser cutting applications, and any application where beam quality matters.

4. Using the Calculator

Tips: Enter wavelength in meters (e.g., 532 nm = 0.000000532 m) and beam waist in meters. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical beam divergence value?
A: For common lasers, divergence typically ranges from 0.1 to 10 milliradians, depending on wavelength and beam waist.

Q2: How does divergence affect laser applications?
A: Lower divergence means the beam stays collimated over longer distances, important for applications like free-space communications.

Q3: Can this calculator be used for non-Gaussian beams?
A: This equation is specifically for fundamental mode Gaussian beams. Multimode beams have different divergence characteristics.

Q4: How does wavelength affect divergence?
A: Longer wavelengths (e.g., CO₂ lasers at 10.6 μm) naturally have greater divergence than shorter wavelengths (e.g., visible light) for the same beam waist.

Q5: What's the relationship between divergence and beam quality (M²)?
A: Real beams diverge M² times faster than the diffraction-limited Gaussian beam described by this equation.