Automated vs manual lensometers

**harry888** · 12-20-2003, 06:50 PM

One of my dispensers just took a course for the ABO and was surprised that better than half the class did not know how to do lensometry, all those offices had automated lensometers.

Are manual lensometers really turning into dinosours?

I've had a few instances where a patient will return stating their glasses were made wrong, we rechecked, then called the place that badmouthed us, and found they had used an automated lensometer which noone knew how to calibrate.

Note, Massachusetts now has a practical for it's license which includes lensometry (manual).

comments?

Harry

**chip anderson** · 12-20-2003, 08:37 PM

Haven't you figured out the logic behind automated machienery and instruments? The whole idea is to eliminate skilled (high priced) personel and personel period when possible. Those personel you must have should be easily replaceable.

Many doctors now can replace the office help in a single day for no better reason than an inch shorter mini-skirt or the present help wanting a raise.

Chip

It's not lensometers that are dinosaurs, it's competent skilled people.

**edKENdance** · 12-20-2003, 09:38 PM

I haven't been involved in the industry as long as some of the folks on here but I have to say manual all the way. We use 2 B&L lensometers in our lab but our opticians have an automatic out front. It's safe to say that out of 3 jobs an optician will come to the lab to use the manual lensometer to verify the prescription. Not sure what automatic we're using because I never use it but from what I've been led to believe, it's not really trusted when it comes to small cyls and progressives.
.02

**BobV** · 12-20-2003, 10:26 PM

Manual all the way...our clinic has an autolensometer but the techies still come to the optical to have me check for prism because the auto can't it. By the way, I try to show our techs what to look for when a pair of glasses has prescribed prism. All of them couldn't tell base in from base up.

Bob V.

**Chris Ryser** · 12-21-2003, 04:34 AM

If you dont' have a manual one you can still neutralize the lenses if you know how to do that.

**Rick Strong** · 12-21-2003, 06:28 AM

We have an auto that used for pre-testing which works well enough for that.

We keep two manuals in the lab for checking jobs, being one of the dinosaurs myself, I prefer the manual.

Rick

**PAkev** · 12-21-2003, 10:46 PM

I have a manual Cannon in the lab and my doc has an auto, Humphreys, in his office. The auto gets close readings but only with numbers. However, the manual enables you to see the lens characteristics (ie. centration, prism, progression, etc.) while also identifying the numbers. Warped and/or distorted lenses will get by the auto lensometer fairly easy but can be easily identified on the manual.

Either way, you need to be a little open minded because one can be .12 or 1/8th UNDER and still be within tolerance and another be .12 or 1/8th OVER and still be within tolerance. Although no one is really wrong and no one is really right, folks tend to get excited when the RX in question is showing up with a .25 difference. In that respect, it is important to keep lensometers in the same office in sync with each other as much as possible.

Merry Christmas
Kevin

**Pete Hanlin** · 12-22-2003, 08:19 AM

I have an old B&L lensometer sitting in my office (in fact, looking at it I just realized I left the lamp on over the weekend)... Not too many months ago, someone from our European quality operations was in my office and he commented on my lensometer. "Ah, I see you've found an antique to decorate your office..."

Yes, he was serious- and surprised to hear I don't use an automated lensometer for most of my quality work. I think people forget that an automated lensometer only measures power over a very small surface area of the lens. Nothing like a manual for spotting waves and other aberrations!

That said, PAKev brings up a very valid point. In some of the larger labs I've visited, its possible to find a significant variation in the readings one gets from the various auto-lensometers present. They do need to be calibrated, and it doesn't hurt to set the index of refraction to match the lens you're reading!

**chip anderson** · 12-22-2003, 08:51 AM

I have several old lensometer/vertometers in the office. I have found that the A-O is more likely to show fuzzy images on lenses, especially contacts if the quality is not perfect. The B&L shows "exact" powers more accurately.

Anyone else with any sort of comments on these or other instruments?

Chip

**karen** · 12-22-2003, 10:57 AM

Can I tell you how many times an account has sent a job back to us asking us to redo it, only to find when we neutralize it on our manual lensometer that it is fine? When we can the office to ask how they checked it they almost always answer on an automated lensometer. I do not trust them and don't like to use them myself. My dad's office has one of the older Humphreys that works ok but the newer fangled ones that look like a regular lensometer seem to always cause problems. Many offices seem to think that they do not need to be calibrated either. I especially don't like the way they neutralize a PAL...

**Darryl Meister** · 12-22-2003, 04:23 PM

I think people forget that an automated lensometer only measures power over a very small surface area of the lens.

However, while the larger aperture in manual focimeters will "pick up" more, it will also pick up some of the astigmatism surrounding the measurement points of progressive lenses, which will affect your readings slightly. Of course, automatic focimeters have a bunch of other issues to worry about when measuring progressives...

Best regards,
Darryl

**Robert Wagner** · 12-22-2003, 08:39 PM

chip anderson said:
I have several old lensometer/vertometers in the office. I have found that the A-O is more likely to show fuzzy images on lenses, especially contacts if the quality is not perfect. The B&L shows "exact" powers more accurately.

Anyone else with any sort of comments on these or other instruments?

Chip

Like Chip says,
The B&L shows the exact powers more accurately and I use 2 of them, I like the fact you can place the prism rings in any power you need in the B&L to neutralize the Rx and or line up the lens for edgeing.
I have used the Marco with the prism rings built in and I still perfer the B&l. I too must be an oldie.

Robert
;)