1. What is Ultrasonic Beam Spread?

Ultrasonic beam spread refers to the angular divergence of an ultrasonic beam as it propagates from a transducer. It is a fundamental concept in ultrasonics that determines the resolution and coverage area of ultrasonic systems.

2. How Does the Calculator Work?

The calculator uses the beam spread equation:

Where:

• \( \lambda \) — Wavelength of the ultrasonic wave (m)
• \( D \) — Diameter of the transducer (m)
• 1.22 — Constant derived from the first zero of the Bessel function

Explanation: The equation calculates the half-angle beam spread based on the ratio of wavelength to transducer diameter, following the principles of wave diffraction.

3. Importance of Beam Spread Calculation

Details: Accurate beam spread calculation is crucial for designing ultrasonic systems, determining resolution capabilities, optimizing transducer size, and predicting coverage patterns in various applications including medical imaging, non-destructive testing, and underwater acoustics.

4. Using the Calculator

Tips: Enter wavelength and diameter in meters. Both values must be positive numbers. The result is given in degrees, representing the half-angle beam spread.

5. Frequently Asked Questions (FAQ)

Q1: Why is there a 1.22 constant in the formula?
A: The constant 1.22 comes from the first zero of the Bessel function J₁(x), which describes the diffraction pattern of a circular aperture.

Q2: How does wavelength affect beam spread?
A: Shorter wavelengths (higher frequencies) result in less beam spread, providing better resolution but reduced penetration depth.

Q3: What is the relationship between transducer size and beam spread?
A: Larger transducers produce narrower beam spreads, while smaller transducers produce wider beam spreads for the same wavelength.

Q4: Are there limitations to this equation?
A: This formula assumes ideal conditions with a perfectly circular transducer and uniform excitation. Real-world factors like transducer imperfections and near-field effects may cause deviations.

Q5: Can this calculator be used for all ultrasonic frequencies?
A: Yes, as long as you know the wavelength (which can be calculated from frequency using λ = c/f, where c is the speed of sound in the medium).