Laser Beam Spot Size Calculator: Determine Focused Beam Diameter

Calculate Laser Beam Focused Spot Size

Utilize our Laser Beam Spot Size Calculator to precisely determine the focused diameter of a laser beam. This essential tool helps engineers and researchers in optical system design, ensuring optimal performance by calculating the diffraction-limited spot size based on key parameters like wavelength, focal length, and input beam diameter.

Formula:

Laser Beam Spot Size Formula

The diffraction-limited focused spot size (d) for a Gaussian beam is calculated using the formula:

d = (4 × λ × f) / (π × D)

  • d = Focused Spot Size (Beam Waist Diameter)
  • λ = Laser Wavelength
  • f = Focal Length of the Lens
  • D = Input Laser Beam Diameter
  • π ≈ 3.14159

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