2 doctors weighed in:
When we say +1, -2. +0.5 etc. For power of spectacles, what is the unit these numbers?
2 doctors weighed in

Dr. Emil Chynn
Ophthalmology - LASIK Surgery
In brief: Prescription
The unit is diopters.
Lasek can give you better than 20/20 vision because the laser is accurate to +/-0.01 d vs +/-0.25 d for glasses or contacts.

In brief: Prescription
The unit is diopters.
Lasek can give you better than 20/20 vision because the laser is accurate to +/-0.01 d vs +/-0.25 d for glasses or contacts.
Dr. Emil Chynn
Dr. Emil Chynn
Thank
Dr. David Kira
Ophthalmology
In brief: Diopter
The plus powers are for reading and make you more nearsighted and reduce your focusing or accommodation requirement.
The units are in diopters or the ability of the lens to converge light.

In brief: Diopter
The plus powers are for reading and make you more nearsighted and reduce your focusing or accommodation requirement.
The units are in diopters or the ability of the lens to converge light.
Dr. David Kira
Dr. David Kira
Thank
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