The Queen has received her smallest birthday message in the form of an etching made on a strand of hair from a corgi.
Ion beam technology was used by a team from the University of Nottingham to inscribe the words ‘Happy 90th Birthday Your Majesty’ on the tiny hair fibre.
Nottinghamshire Corgis Cracker and CJ, which are said to be from the same blood line as the Queen's own dogs, donated the samples for the experiment.
The team at the newly-opened £12m Nanoscale and Microscale Research Centre in the School of Chemistry then etched the birthday wishes using a beam of gallium ions.
The centre only officially opened this week and specialises in scientific study using microscopy.
It promises to progress a number of scientific areas including medicine, materials for energy production, storage, electronic devices and novel catalysts.
Dr Chris Parmenter, one of a group of scientists who hold the world record for creating the smallest test tube, used a Focused Ion Beam Scanning Electron Microscope, which can manipulate materials on the nanoscale.
The scientists had to work with a measure of nanometres, which measure just one millionth of a millimetre. One human hair is 80,000 nanometres wide.
The official British Monarchy Twitter feed said: "One of the more unique tributes to The Queen today!"
A spokeswoman for the university said: "As a new research centre, we are delighted that our expertise and technology has been able to provide Her Majesty with such a unique gift for her 90th birthday.
"The etchings and images were carried out using a powerful electron microscope which allowed us to magnify the corgi hair by 5000 times. The birthday message is so small that 1 million of them could be written on the face of a £2 coin."
In addition to the ion beam emitter, the facility hosts a suite of 20 instruments, including 14 electron microscopes with a diverse range of capabilities to image and carry out analytical investigation on a wide variety of materials.
The Centre will also host a state of the art electron beam lithography system; a powerful suite of surface characterisation equipment (X-ray photoelectron spectrometers, Raman microscopy); and a comprehensive sample preparation laboratory.