B Measurements

**Cherry Optical** · 07-09-2007, 09:23 AM

Quick question: Does anyone know the recommend minimum B measurements for the following lens styles:

Varilux Comfort
Varilux Panamic
Varilux Ellipse / Ellipse 360
Varilux Physio / Physio 360
HOYA Summit ECP
HOYA Summit CD
Kodak Precise

The reason I ask is that the frame styles keep getting smaller and smaller (maybe not for your coasties. remember, the midwest is a few years behind) and I see some pretty wild combinations of lenses/frames going out the door here that I have no idea how they are working. For example, if someone fits a VC at 18 high in a frame with a 28 B, there is only 10 mm on the top. In my mind that would not be nearly enough, however, I have been wrong a few times already today... and it's only 9:30AM.

Adam

**Judy Canty** · 07-09-2007, 10:24 AM

Over the years, I've found that less than 10mm of distance vision is usually uncomfortable.

**k12311997** · 07-09-2007, 10:35 AM

10mm above fitting cross is the least I'll ever go usually try to give at least 12 in a myope. Hyperopes do seem to be more forgiving of less distance area.

**KStraker** · 07-09-2007, 10:36 AM

comfort and panamic=18
ecp=18
cd=14
precise=20
don't know about physio

-from OLA Progressive Identifier.

**Cherry Optical** · 07-09-2007, 02:32 PM

Originally Posted by KStraker

comfort and panamic=18
ecp=18
cd=14
precise=20
don't know about physio

-from OLA Progressive Identifier.

These would be the min. fitting heights.

From what I have been able to gather, most people believe 10-12 above the fitting cross is the min. So in this case we would be looking at frames needing to be 30, 26, and 32 in the B measurement. Interesting.

Adam

**KStraker** · 07-09-2007, 03:37 PM

Originally Posted by Cherry Optical

These would be the min. fitting heights.

From what I have been able to gather, most people believe 10-12 above the fitting cross is the min. So in this case we would be looking at frames needing to be 30, 26, and 32 in the B measurement. Interesting.

Adam

Indeed. Sorry, I misread.

**Bill Mahnke** · 07-10-2007, 09:52 AM

HOYA strongly advises that a minimum of 10mm above center pupil be maintained for their Summit ecp (min “B” = 28mm) and Summit cd (min “B” = 24mm) progressives. As stated by others, 12+ mm above center pupil would provide a better field of view/better vision for most wearers.

**Freedom** · 07-23-2007, 01:07 PM

Corridor + 8 is perfect or optimum fitting high

Perfect fitting high +10 to 12 mm. is suitable B mesurement.

Corridor +6 is recommend fitting high.

Corridor +4 is minimum fitting high.