Colourful images showing the vibration of church bells ringing have been released ahead of Christmas, a time when they are traditionally rung in predominantly Christian nations. Jim Drury reports.
These images show the vibration of church bells in unprecedented detail. They were produced at the University of Leicester's Advanced Structural Dynamics Evaluation Centre. Working with local bellfounders, the team scanned the structural dynamics of two large bells using a 3D laser vibrometry system. Around 4,000 measurement locations were examined as the bells were struck at different tempos. When bells of any size are struck the impact causes various different vibrations or modes. The individual profile of each bell affects their frequency and intensity. Christmas bells are a popular feature of the festive season. The chimes ring out to mark the birth date of Jesus Christ - in some churches up to four times during the final hour of Christmas Eve. Bell founding dates back 4,000 years, but it's at this time of year when they're at their most prevalent - with churches, carol singers, and even budding Santas ringing with gusto.