Got a patient who wants to use entire lens without turning her head, to read sheet music while playing piano. She hates the cr39 sv we put her in. Keep in mind this is what she was wearing previously.
Any lens suggestions? Do you think an aspheric would help?
+3.00-0.50 x 090 OU
PD 60/57
Thanks...
A: 55 DBL: 17
If the Rx is right aspheric will not help!
Free form might!
Yes, free form might be the answer. Also, despite what she believes, musicians rarely only move their eyes to read the score. I was a musician long before I wore glasses. Head movement is inevitable. Watch one in action and you'll see that some are barely able to sit still. =)
Ms. Canty is correct about reading the score. She has to learn to move her head. Practice makes perfect.Originally Posted by Judy Canty
She claims she didnt have this problem with the last pair we made. She even claims her bifocals work better. But she still insists on this new pair. Rx reads sharply on power. I think im gonna take the free form route.
Of course she does! There's one in some optical shop every day!
Its encouraging to know I'm not alone.
A: Put her in contacts, problem solved!
B: She bout ready for bifocals anyway (I knows she won't admit it for 3 more years, but..) Try offsett bifocals with segs in the direction and focal length to match the music reading distance.
Chip
Asphericity will only exacerbate the condition. CR39, with the lowest index, and good abbe, is the lens of choice for her. What does she "hate"?
Reduce lens size, and vertex as close as possible, ensuring a curve top frame shape, perhaps oval to control lens thickness. Add a AR coating.
I agree that a contact lens is the best answer.
I would suggest that to her.
Eyes wide open
Most lenses today are made flatter than Best Form Optics, as the cosmetics in "best form" are atrocious ( the base curves are much steeper than patients like). In addition the base curve increases at a higher rate in Plus than minus (per Vogel's Rule). As a result good Aspheric lenses allow us to caputure some of that best form optics back and keep the cosmetics to something the patients like.
Free-form and a good Aspheric design have the same goals, to compensate for todays limited and cosmetically emphasised base curves. The free-form lens and a good apsheric design should have a similar result, expect if the patient has an unusual vertex, face form or panto. Then Free-form would be better. But the same logic applies to free-form as it does aspheric, Free-form is just a more customized aspheric lens.
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