What a ready-made reader assumes
Ready-made readers normally use the same power in both eyes. They do not match different prescriptions or correct each eye’s astigmatism. The College of Optometrists describes them as potentially useful spare reading glasses, while recommending a pair made to individual measurements and prescription.
Use them for the intended distance
Reading glasses are for near tasks, not for driving or watching distant television. The fact that a label looks sharper through a stronger pair does not tell you whether that power is appropriate for prolonged work or for both eyes together.
Bring the task to the appointment
Our suggested comparison uses your ordinary book, phone or hobby at its normal distance. Tell the practitioner whether the spare pair is for a handbag, desk or occasional repair task. Agree on what it can reasonably do and when to use your prescribed pair instead.
Keep routine eye care
Being able to read with a shop-bought pair does not assess eye health. Keep the examination and follow-up advised for you. The linked College statement contains older research; it should not be read as a current quality score for every reader on sale.
Sources & verification
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