Google celebrates 181st birthday of eye test inventor

Google today dedicated its doodle to mark the 181st birthday of French ophthalmologist Ferdinand Monoyer, who invented the popular eye test that is now used in clinics across the world.
The colourful animated doodle, shows a pair of eyes taking an eye exam - squinting at the hard-to-read alphabet chart.
It then finds Monoyer's name on the chart and is seen to be visibly overjoyed.
"Ferdinand Monoyer, born on this date in 1836, rose to prominence as one of France's most famous ophthalmologists," Google said.
Monoyer is known to have developed the dioptre, the unit of measurement for vision that is still used today. The dioptre measures the distance one would have to be from a text to be able to read it.

Most notably, he devised an eye chart where every row represents a different dioptre, from smallest to largest.
"If you look closely at today's Doodle, you might be able to spot a tribute to another of Monoyer's signatures: his name, hidden in the chart," Google said.