perscription vs. analyzer

[daveftc]

I had to move across the country between the time of my eye examandwhen I could get my perscription filled. Things don't look rightinmy new glasses and I am having a tough time getting someone toexplainwhat might be wrong.

My perscription says in the D.V. section of the form:

OD PL -1.25 154
OS PL -0.75 028

These entries are in the Spherical, Cylindrical and Axis columns.

I got the lenses analyzed and the printout says:

Right:
SPH -1.25
CYL +1.25 x 65degrees
PSM HOR 0.00 IN
PSM VER 0.00 DN

Left:
SPH -0.75
CYL +0.75x116degrees
PSM HOR 0.25 OUT
PSM VER 0.00 UP

My questions:

1. Do the lenses match the persrciption?
2. Why doe the lenses have a spherical entry when the perscription is PL?
3. Why is the sign of the cylindrical number different between the two (-1.25 vs +1.25)
4. How does one convert the Axis # in the persrciption to the degree # in the lens? Or should they be the same?
5. What is this PSM stuff and should it all be 0.00 for me?

Thanks!!

dave

[For-Life]

I had to move across the country between the time of my eye examandwhen I could get my perscription filled. Things don't look rightinmy new glasses and I am having a tough time getting someone toexplainwhat might be wrong.

My perscription says in the D.V. section of the form:

OD PL -1.25 154
OS PL -0.75 028

These entries are in the Spherical, Cylindrical and Axis columns.

I got the lenses analyzed and the printout says:

Right:
SPH -1.25
CYL +1.25 x 65degrees
PSM HOR 0.00 IN
PSM VER 0.00 DN

Left:
SPH -0.75
CYL +0.75x116degrees
PSM HOR 0.25 OUT
PSM VER 0.00 UP

My questions:

1. Do the lenses match the persrciption?
2. Why doe the lenses have a spherical entry when the perscription is PL?
3. Why is the sign of the cylindrical number different between the two (-1.25 vs +1.25)
4. How does one convert the Axis # in the persrciption to the degree # in the lens? Or should they be the same?
5. What is this PSM stuff and should it all be 0.00 for me?

Thanks!!

dave

The lenses are dead on. There is a change of a degree in the right and two in the left difference, but that is within tolerance and could of been caused by wear and tear - so that would not affect you.

The reason why the prescription is different is because one is measured in plus cylinders and the other is measured in minus cylinders - It is like using inches versus centimeters.

To covert the minus cylinders to a plus cylinder you
1. Add the cylinder and spheres together to get the spheres
- So in the right eye the Plano (0) becomes -1.25, because -1.25 and 0 = -1.25.
2. Inverse the symbol for the cylinders - so that a -1.25 becomes a +1.25
3. Change the axis by 90 degress within a 0-180 degree range - so 154 becomes 64.

The PSM is just prism and the glasses say that they have no prism, which from you put down is right.

Hope that helps

[daveftc]

Thank you For-Life!!

I also guess that the PSM HOR 0.25 OUT in the left lens is within tolerance?

Time to get a new exam I guess...

Thanks!

dave