Five Muslim scientists who shaped optics
Optometrist Shamina Asif traces the historical contribution of Muslim scientists to the field of optometry
OT took the opportunity to talk with optometrist and Dudley Local Optical Committee chair, Shamina Asif, about the historical contribution of Muslim scientists to the field of optics.
She shares insight below on five key figures who shaped the profession UK optometrists know today.
Improving cataract surgery: Yuhanna Ibn MasawaihYuhanna Ibn Masawaih, (Mesue the Elder) 777–857, was the first to discuss removal of cataracts with a hollow tube via suction rather than couching which involved using a bent needle to drive the lens into the posterior chamber. Couching was a dangerous procedure commonly practised in the west till 1748. It was a 10th century Iraqi scientist, Al Mawsli, who started practising the procedure of using a hollow tube to remove cataracts, which has formed the basis of how surgery is done today.
Prolific author and detailed anatomical illustrations: Ibn IshaqIbn Ishaq (Johannitus), 808–873, combined Greek doctrines and his own observations to produce 36 books describing cysts, tumours, ulcers and their causes, as well as detailing surgical techniques. He produced a detailed anatomical illustration of the eye – diagrams today that we find in our rooms explaining conditions to patients.
Advanced surgical techniques: Al-RaziAl-Razi (Rhazes), 860–932, contributed to Islamic ophthalmology, documenting advancing surgical techniques in his famous book Kitab Al-Mansouri – a medical manual which was used widely in medieval Europe.
‘The father of optics’: Ibn Al-HaythamThe most revolutionary work in the history of optics was by Ibn Al-Haytham (Alhazen), 965–1040. He wrote the Book of Optics disproving the Greek theories of how the eye sees.
The Greeks said that sight occurred because of rays emanating from the eye itself, however he rejected this and through a series of experiments showed that light travelled in straight lines and that we can see due to light reaching the eye from a source.
Ibn Al-Haytham said that the retina was the centre of the vision and the impressions that it received were transferred to the brain by the optic nerve for the brain to create a visual image.
He proved his theory through experimentation, using dark chambers – this was unusual for his time as physics had been more like philosophy without experimentation.
Ibn Al-Haythem also studied lenses, experimenting with different mirrors: flat, spherical, parabolic, cylindrical, concave and convex. He treated the eye as a dioptric system by applying the geometry of refraction to it.
Ibn Al Haythem laid the foundations for optical devices like cameras – the word camera itself comes from the Arabic language.
Other scientists include Al-Ghafiqi, who resided in Cordoba, Spain, and treated trachoma. This procedure was used until World War I. Ibn Isa from Baghdad, Iraq wrote the Notebook of the Oculist describing 130 eye diseases and was the first to point out that eye disease can be a consequence of general disease.
Today we know this is the case with systemic disease like diabetes and autoimmune conditions affecting the eye. He also described treatment of chalazions, styes, trichiasis and pterygium, all of which we are still practising today when advising patients of hot compresses and cleaning of eyelids.