Blindness/Visual Impairment/How are we farsighted?



I'm really curious about optics.

Can you please explain to me the SCIENCE between WHY and HOW someone in their twenties can be hyperopic, or farsighted?

I understand that everyone is born farsighted. Their eyeballs lengthen as they grow to 3 years old. Some people say that, then, children's eyeballs lengthen to a normal size because they do enough close work after the age of 3 (just like how someone becomes myopic).

Why is one adult hyperopic (NOT PRESBYOPIC), but not another adult with the same age? Please explain the science behind this, for example highlighting the parts of the eye anatomy involved, or how maybe light affects farsightedness, etc.

Dr Mannu C Rajnani
Dr Mannu C Rajnani  

Dr Mannu C Rajnani
Dr Mannu C Rajnani  

The amount of information you have asked for in so much details will entail whole book, basically just to explain you it is not because children dont do near work it is just that eye ball lenghtens and all adults are NOT HYPEROPIC( Not PRESBYOPIA) some are myopic and some astigmatic, all depends on size and shape of eye ball and also most important is habits of patients lying down reading, lying down watching TV and playing video games and also dietary habits of improper nutrition and yes genetic or hereditary factors play role to a extent
you can have better visualisation of your queries on following internet sites

if you any further questions please revert back to me on my email address at ""
thanking you
Dr Mannu C Rajnani
Dr Mannu Laser Eye Surgeries
1st Floor Sarasati Society, Plot 433, TPS 3,
15th Road, Khar(West), Mumbai 400052.INDIA
Tel: 91-22-26006801-26004467 & 26007828

Blindness/Visual Impairment

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Dr Mannu C Rajnani


I am a Laser Eye Surgeon specializing in LASIK-Excimer Laser to remove glasses permanently, Phacoemulsification-No stitch surgery to remove Cataract and insertion of Intraocular Lens, Glaucoma, Squint Surgeries, Laser for retina for hypertension and diabetes


Practicing since more than 27 years now and conducted thousands of surgeries for LASIK (waveguide), Cataract,Phacoemulsification, Glaucoma and Squint in anterior segment of the eye

DR MANNU LASER EYE SURGERIES At 1st Floor Saraswati Society Plot 433 TPS3 Khar(West) Bombay 400052 India,Tel: 91-22-26006801-26004467&26007828 Mobile:91-9821032072 Bombay Ophthalmological Association, Maharashtra Ophthalmology Association All India Ophthalmology Association Glaucoma society of India Eye Trauma association of India

M.B.S., D.O.M.S., M.S.(Ophthalmology)

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