Measuring Pupillary Distance (PDs)

Considerations and a how-to for measuring customer pupillary distance (PD).
Learn More about Laramy-K OpticianWorks: opticianworks.com
Connect with us:
/ opticianworks
This video was produced by Laramy-K Optical
Laramy-K Optical is a digital surfacing and coating lab unlike any other. We provide our customers with independent, high-end alternatives to corporate brands. Through craftsmanship, technology, and independent, innovative vendors like Younger, IOT, A&R, and Quantum Innovations we offer our customers the Integrity portfolio of freeform lenses and coatings. Made in the USA, the Integrity brand is not a generic house-brand, but is the absolute best available, designed to give the wearer that “wow!” experience.
In addition to the digital line, we still offer conventional surfacing, including glass. Maintaining traditional equipment gives our customers vastly more flexibility in their dispensing, particularly when it comes to more difficult prescriptions.
Learn More: www.laramyk.com

[@LaramyKOptical]

See also: www.2020mag.com/article/meet-your-pupilometer

[@blairtaylor9552]

This is a must-study link for understanding the complexities of taking accurate PD's! Thank You! One other thing I'd really, really, really, love to know- is how the internals differ from a cheesy sub-$100 Chinese pupillometer, to something like the Reichert $800 pupillometer made in Japan. The latest versions Hilco and Essilor are selling, look like they are buying the cheap Chinese knock-offs, and then putting a brand name sticker on it! Everybody is taking the cheapest route possible nowadays. I wish somebody would dissect a few of these and shed some light as to whether there's any functional differences in parts, or build quality, or electronics, between the different makers and price tiers.. I would gladly pay for a copy of that study!

[@LaramyKOptical]

@@blairtaylor9552 With the ever growing use of electronic measuring devices I doubt anyone is ever going to do a side-by-side breakdown.

[@melissayouell8629]

THANK YOU John - u give me faith in teaching attitude care and approach

[@loveiliang1957]

I Love How you teach! ♥ Thank you 😊 🙏

[@luisgomez1211]

Hello Laramy, I'm here again, listening how to measure pupillary distance...thank you...

[@joshandersons6914]

Amazon sell the PD measurement device around $100+ if your optician or optometrist give you a hard time and not giving you your PD, you have the option to buy one.

[@ajdigifuture4910]

Another Awesome Video!!!!!!

[@SpiritualSway]

Helpful big thanks from Sri Lanka ❤

[@ifajuitan]

thank you for the thorough explanation

[@andreanobile330]

Thanks so clearly explained!!

[@devincritch1008]

Very Informative video as always, you have a good way of teaching the material. I actually used some of your videos in the past when I was doing my Opticians course to help with prism. Before COVID our optical invested in a digital measuring device, that is attached to an iPad and theres a sensor on the frame. Everyone was very skeptical at first about using it and wondering if it was accurate. So for the first bit we would do both, and generally it is the same (the digital one goes to tenth, which I personally think isn't necessary), it comes down to the user of the device if the measurement isn't accurate. The device can also do height (not ST), panto, vertex, wrap, and reading distance. I think the pupilometer is still the most efficient and best way to do it.

[@LaramyKOptical]

Yeah, regrets I've had a few... one being I wished I had a year of OptiKam Pad use so I knew it backwards and forwards. I'm sure after you have used it fifty times it becomes like anything else and just part of what you do. I'm sure part of that s confidence in it and then your presentation of it to the customer.

[@cathy953]

I consider myself fortunate to have selected the options directing me to you. KZbin is my access door to you and the information you are making available to our world. I am enthusiastically studying your informative videos. It’s obvious that your understanding of the information is definitely deep. I find your presentations clear, very useful and delightfully entertaining. I am learning so much information. You are a gifted teacher. I am in my 70’s and have Parkinson’s disease. I have trifocals and wearing glasses has presents difficulties because of my tremors and uncontrollable head movements. I am in the process of choosing new glasses and thought that progressives would be a better option because the line in the trifocals are infuriating. Got any ideas or direction for me ? What suggestions do you have ? Being able to see really does affect a sense of well being and I really need help . I want to make sure I get the right information and go to the right lab . Thank you for your time , Cathy

[@LaramyKOptical]

Would you please email me (John) through the OpticianWorks.com website. Thanks

[@monicaosorio9564]

Lol 😂 you make everything so fun!

[@ophthojooeileyecirclehisha4917]

thank you thank you

[@leiyue812]

Great video, again! BTW, is the pupil height measurement important for basic single vision lens? I found some optician mark it and some didn't do for my previous glasses. Thanks.

[@LaramyKOptical]

Basic single vision, powers under 5 no need at all for an OC height. I think that is next weeks video!

[@marieziegler5088]

As always, I love your teaching. I needed this video for validation. An optician at our practice never uses a pupilometer. Instead, she places dots on the lenses before handing them to the patient for measurement. She then eyeballs the placement, then measures the original dots and gets her measurements from there. She does the same thing for OC and progressive measurements. I thought maybe I was too old school and was missing a new and modern way. Is this being taught anywhere? Your thoughts?

[@LaramyKOptical]

LOL Spitting coffee out my nose --- um, no, just no. I can't even begin to cover everything that is wrong with that. You have a pupilometer and she refuses to use it? Sorry but that is just plain ridiculous. The straight up dot methods do have their place. But what you are describing her doing makes no sense at all.

[@marieziegler5088]

@@LaramyKOptical Thanks! I appreciate this humorous and validating response. No more will I question myself.

[@kalivianel]

Great video! Some customers say they see two spots in the pupillometer. Is there a danger to having wrong measurements?

[@LaramyKOptical]

Can't say for sure but if things look and sound right otherwise I guess I'd trust it. Are we talking about 1/1000 people 1/100 or 1/10? 1/1000 eh no biggie. 1/10 rut-ro time to think about another pupilometer or an electronic measuring device. I'll mention in an upcoming video that you are basically forced to use what you are provided with where you work. Not really much you can do about it. If you can prove the tool is off make your case for a new one but if it isn't important enough for the owners to worry about I guess you don't let it keep you up at night? John

[@inquisitivenessandcontempl9918]

I saw two marks at infinity. I am confused now. And that pupilometer displayed the PD of 70mm, while two other optometrists at two different offices measured 72 mm with a ruler.

[@filipevitorio908]

Hi ! I loved your video, very clear ! I have a question. When I got my PD measured I kept my eyes on the dot, but I blinked a few times during the test. I didn’t know if I should keep my eyes wide open. Do you think my PD measurement will be off ? Thank you

[@LaramyKOptical]

You'll be just fine. We all blink during the measurement.

[@jeannettevivas1227]

Hello great job . Thanks for all your videos . I have a question. Recently the lab . told me that its not a Big deal the Descentración when the lens its for simple vision and the astigmatism its at 180*. I would like to know your opinion. Sorry if i have any mistakes, Im from Venezuela.

[@LaramyKOptical]

It is possible for a sphereo-cylinder lens to have 0.00 along the 180. In those rare cases you don't really have a PD and "close enough" on decentration is good enough. But you still need to keep the rest of the lens in proper orientation. Except for the 0.00 at 180 the answer would be a very firm NO decentration matters and we should always pay attention to it. Keeping in mind that as power goes up so does the need for accuracy.

[@misuterinaso]

Thank you John for your amazing videos! May I ask for some tips on using the pupilometer? I'm still new to opticianry so your tips would really help me out. From the video, I learned that we are trying to cover that spark in the customer's eyes using the wire. But when I tried to use the pupilometer, their pupils wouldn't stay at the same place. When I tried to double check the position after I'm done with both eyes, very often their pupils moved a little, so I have to move the wire again. And after I moved the wire, their pupils moved again, so I had to adjust the wire again, so it feels like a sisythean task to me. Would you have any tips on how to deal with this situation? I don't mind spending more time, I just want to make sure that the PD is as accurate as it can get.

[@LaramyKOptical]

Many things come to mind. First is, as we say, LOCK & LOAD so work on doing it quite quickly no back and forth, no one eye at a time. Second is be sure your are telling them what to do. STARE AT THE _________. You do get a little eye movement and it may seem like a lot but it is probably less than 1/2 a millimeter. Just practice as much as you can it'll become second nature. Do look inside it and make sure everything is working like it should, sometimes just a battery swap helps. And work on your own position - are you very tall/short? Is the dispensing table too wide?

[@misuterinaso]

@@LaramyKOptical I guess my mistake is that I always ask the customer to sit straight (like when I get their oc), and I had to really reach over to use the pupilometer, I'll try to have them lean over a bit in the future. And I'll also try getting both eyes at the same time from now on and see if it works better for me, cuz it was my coworkers who taught me to do one eye at a time (and toggle the switch to block the other side)

[@LaramyKOptical]

@@misuterinaso Goodness no. The occluder is only necessary if they have one "wandering" eye. That's 90% of your trouble.

[@Dolvak123]

Hi! First of all, thanks for your video, great content :). I have 2 questions, as I just bought new glasses and have the feeling that they might have measured my PD wrong. i) Does it matter whether the metal bar is rested on the forehead? The one who measured my PD did put it on my nose, yet my forehead was not resting against the metal bar. ii) Does the matter is the PD-left eye and PD-right eye are wrong, when the overall PD sums up to the correct number? This time they measured 31.5 left and 28.5 right (60 in total), while last time they measured 30 left and 30 right Looking forward to hearing your response! :D

[@LaramyKOptical]

Just depends on the power of the lenses and/or if they are progressives. Anything much over 2.50 it can create some problems. Anything under 2.50 it almost doesn't matter. Anytime a progressive is off more than 1mm it is a problem.

[@kellz6266]

Where I work, we are still required to wear masks, so bad breath isn't as much of an issue as it used to be! And we also wipe down the parts of the PD that touch the customer's forehead/nose with an alcohol pad before each use. You should include in this your video, especially nowadays.

[@LaramyKOptical]

Good point on the alcohol wipes. I do mention that on the website - forgot to mention it here. Press top dispensers and KImwipes are a more economical way. I also mention the importance of washing your hands often. The actual statement is - "As an optician the closest you ever get being in healthcare is the need to wash your hands often." John

[@tripusa2021]

Hi John, I am preparing for ABOP. How you calculate intermediate PD. This question is in the simulation. Thank you.

[@LaramyKOptical]

Sorry can't help you much on that one. Real world = for full near subtract 2 from each eye for intermediate subtract 1 from each eye. ABO - School nonsense I think I recall that the Brooks Ophthalmic Dispensing book has a series of complicated charts based on distances. Making a mountain out of a mole hill as usual.

[@jailoeil]

First point : I'm french and I must aplogize for my poor english. Second point : I know this is a relatively ancient video, but maybe will you read that however. I am an optician, and I like to see your videos because I'm always interested of what I can learn from others opticians, especially from others countries, with perhaps another methods. Your videos are always good, precise and in a pedagogical way. Thank you. But there is a difference between my habits with the corneal reflection pupillometer and what you explained in this video. What you called "monocular PD" and "binocular PD" is different for me. Your monocular PD, I call it "right eye half-PD" or "left eye half-PD". Your binocular PD, I call it "(total) interpupillar distance". But that's not just only a translation stuff. Because I use the words "monocular" and "binocular" too, but it depends of the position of the selector that close or open the eyes windows. For me, monocular is the measure with only one eye opened, binocular with the two eyes open simultaneously. So I can measure "half-PD" (your monocular), either "inter-PD" (your binocular) as well in monocular way or in binocular way. For example, i'm in use to measure the two "half-PD" (your monocular) but with the two eyes opened (like you explained), except when there are prisms. In this case, I measure the two eyes separately, each one with only its window opened. The other reason is because this way to measure is like masking and unmasking each eye alternately, and check if there is no phoric problem suspicion (lateral eye movement). The most often, the measure is with separated eyes for unifocal lenses, and with both the two eyes for multifocal or progressive lenses, except in case of prisms. I hope that I succed to explain the difference in english. I'm pretty sure you use the pupillometer in an equivalent manner, but because you didn't talk about the windows selector, I was wondering if you use it, and what could be your advices or tips. Thank you to read me and best regards.

[@LaramyKOptical]

Interesting. We use the term occluded or occluder for one eye blocked. I used the lever a handful of times. And it has been so long and I am so old I can't remember why. I think it was when it was the only way I could get them to see what they should see.

[@jailoeil]

@@LaramyKOptical I try to explain with my poor capacities in your language. Thank you for your understanding. So, occluder is what we need to give a monocular or binocular vision, in my way to work. It was just to give you this information, because I was surprised of that you didn't use the occluder frequently. I found really interesting to share and compare our way to work. I like to improve my knowledge and my abilities. That's why I would thank you so much for your videos, and thank you because you took the time to answer me. Merci beaucoup 😉

[@jemadv1594]

Just tried 2 diff. pairs of progressive and cannot use them. I'm sitting in the office chair looking straight ahead. If I turn my head 10mm, the fishbowl effect is so bad the desk in front of me looks like a teeter totter up / down. The channel is so narrow that nobody could use them. Just started wearing glasses at 60 with very little magnification. Single vision great. Readers great. Progressives... No Did they record something wrong ? This was Lenscrafters who did Exam and glasses. Thanks for your informative videos. 👍

[@LaramyKOptical]

I wish I could troubleshoot but I'd need you and the glasses in front of me. Taking your description exactly as written, yes, it sounds like something is wrong. But it could also be a case of a little teaching on how to wear/use them? Like I say over and over and over progressives aren't for everyone. Sounds like you already found the other videos on progressives. We have a How To Use Your New Progressives coming out in 2023. John

[@ImDenq]

Hello, is it possible to readjust the optical center of the lenses? For example make it go from 70 to 68 without changing the lense? Thanks!

[@LaramyKOptical]

Short answer is sure! Long answer is you are mixing up several concepts and without grasping all the different ones and how they relate to one another the real answer to your assumed question is probably no. OpticianWorks.com.

[@pkfilseth]

I really appreciate your video! But have a question ... starting at around 12:48 in the video, you show monocular (26 and 29) and binocular readings (56) on the white board. This confused me a little, because I would have thought the binocular reading (56) would be the sum of the monocular readings shown ... but 26 + 29 is 55, not 56. Am I missing something, or is there just an inadvertent math error here?

[@LaramyKOptical]

The example on the left and the example on the right are not necessarily the same person. I can see now how that might be a tad confusing. Sorry about that. [secret between us - they aren't even the same sex].

[@dahon7981]

Hello sir, the lenses I using have a PD of 66mm. However, my frame broke after 2 months of use. I couldn't find a replacement but still wanted to keep the old lenses. And I found a new frame, but its bridge is 2mm smaller than the old frame. I don't know its ok if I choose it. Or should I find a new one with the same frame bridge with old frame. Thanks adv.

[@LaramyKOptical]

If your lens powers are under 5 you should be just fine.

[@p.williamfox6417]

I have been struggling with issues from damage to the macula in my right eye resulting in (macula pucker) for a while now causing distortion from center out to 1 o’clock to 3 o’clock; the 1&2 bars on astigmatism charts pretty much disappear in the right eye. Over time my right eye has adapted to using peripheral especially opposite of distortion. When my pupil distance is measured the technical or actual pupil distance of OD 31.5/OS 32 doesn’t match the way my eyes actually are working when looking at objects and from what I can tell by about 1.5 mm off on the eye with damage compared to what my eye actually uses. I kept having issues with distortion especially progressives so after noticing this myself I ordered glasses with pupil distance of OD 30/OS 31 and the distortion issues went away for the most part, but If I get glasses through a clinic they never get what I try to explain. They do understand the segment height needing to be slightly lower than normal though. Is there any technical information to back up what I am explaining?

[@LaramyKOptical]

I'm a firm believer in, "if it works for you, keep doing it." 1 or 2 mm of play is about what you have when fitting a progressive so the differences in PD are negligible. I never agree that you can fit a progressive "a little low." I mean if you are on the edge of a fitting height of 18 and 17 and use 17 that is fine, but not more than a mm or maybe two. If they are "dropping" the height that isn't a good thing. Honestly I'm surprised you do OK with progressives at all. I'd do my best to find a patient independent optical to experiment with. Knowing that since there are no rules here you would be paying for the experiments.

[@p.williamfox6417]

@@LaramyKOptical Thank you for the reply. It’s greatly appreciated. I definitely have a better visual experience with single vision or high quality bifocals, but seems like nobody wants to do bifocals anymore.

[@vickymueller288]

My prescription has 4 numbers - 2 for distance and 2 for near. I understand the distance but when ordering progressive lenses they only ask for 1 number for near pd. Do I add them together?

[@LaramyKOptical]

You won't like my answer - if you are getting progressives go and see a good optician in person. I have nothing at all against online glasses sales for low powers and single vision. Progressives online is just asking for trouble and wasted money.

[@danielch6662]

I side-stepped this problem completely after accidentally stumbling onto a different solution whilst wearing contacts. I reasoned that it is unhealthy to wear contacts for too long, so why not wear only one on alternate eyes on alternate days. John would know where I am heading with this. 🤣 I wore contacts for not much more than a year. But later, when I got presbyopia, I had already been buying all my glasses online for quite a few years. I heard a lot of bad things about bifocals, trifocals, and progressives ... mostly from my mum. I was concerned that I would be unable to try them out. Online glasses were cheap enough, I had decided to get two pairs (one for distant, one for near), when I remembered what I was doing with contacts years ago. So I swapped one lens from each pair with the other. _This would be sure to avoid any lazy eye problem from developing_ I reasoned since I plan to wear each pair on alternate days. Never looked back! 😁 Only much later did I learned this was called monovision.

[@reikisponge]

So based on the progressive and mono PD, it got complicated. I am trying to find a smaller round frame to optimize pd for the thinnest part of the lens to get the thinnest possible glasses which being progressive eligible Any advice?

[@LaramyKOptical]

Many other videos covering all that here: kzbin.info/door/dfKXBLjBDbX2X2g0XuAbmwvideos

[@preka88]

What if someones nose goes a bit on one side more and moves the Corneal Reflex Pupilometer in one way more do you get a false reading? How really accurate is it for mono pds? Thanks!

[@LaramyKOptical]

That is why the EMDs or electronic measuring devices are the preferred method now. As power increases so does the need for accuracy. You work with what you have. Pupilometer was the go-to for 25+ years and not a bad tool.

[@lindsayruddock9141]

Hi, if one is ordering progressives / varifocals, which PD is used, the near, the intermediate or the distance ?

[@LaramyKOptical]

Distance and when possible what is called a monocular PD. I've got absolutely NOTHING against online ordering but I don't recommend it for progressives.

[@hiddengem2930]

Do you round up or down? If it's 62.5??

[@Ayumu88]

Why would you round up or down with your binocular PD? You are not supposed to be rounding up or down. That means that you don't have dual PD's, each eye has a different PD.

[@carolineblanchard4769]

I recently had an optometrist appointment, and my prescription was updated. PD also was measured as 58 mm. Previously, my PD was listed 65 mm, and it’s possible I’ve been wearing glasses with this PD for a decade without realizing it. While I see very clearly, I’ve been having issues adjusting to my new glasses, particularly eye strain when doing computer work. Would a PD change of this nature cause eye strain with single vision glasses for mild myopia and astigmatism?

[@LaramyKOptical]

58 from 65 certainly could cause problems. I'd need to know more about the powers to better advise. The higher the power the more it would matter. I'd have them check IF the old glasses were actually made to 58. FWIW 58 is very narrow (my own PD in fact) while 65 is pretty wide. You should get an idea of which one is right just by looking in the mirror. If 65 is correct and the new glasses were made right should adapt over time. But a DECADE! in a 58 might mean it will take a while. Anyway - single vision, mild myopia and astigmatism it shouldn't be a big issue. John

[@carolineblanchard4769]

Appreciate the feedback! I’ll give it some time and hopefully the eye strain will resolve itself.

[@altonyee4488]

When my optician measured my PD, she held the pupilometer. After she took the measurement, I told her the tool was askew, I.e., she didn’t hold it level. She said it didn’t matter. Is she correct? She was prescribing progressives for me.

[@LaramyKOptical]

If she was a little higher or lower than you are it shouldn't matter very much. If she was like crazy off crooked with one eye closer to the pupilometer than the other I'd be a little concerned. Any chance she had it already from a previous order?

[@truptishah9074]

Good morning! kindly guide me on how to measure PD for a px who has been prescribed a progressive lens with a prism incorporated in it. Regards- Trupti

[@LaramyKOptical]

Same as you would for any progressive.

[@GeneaVlogger]

Takings PDs....the reason why we kept a bowl of mints in the store 😂

[@shawn2603]

should you set it for infinity if your goal is reading glasses?

[@LaramyKOptical]

No that would be the opposite. Crank that knob all the way the other way. Just don't forget to put it back or you can get in a lot of trouble. That is why it is better to do -4 from the distance.

[@eddie45658]

What if i wasn't stareing rite at the target correctly, is my measurement going to be wrong, , or would the optician see if wast exactly looking in rite direction toward the target?

[@LaramyKOptical]

I wouldn't let it worry you. Unless your powers are quite high +/-5 or more it won't make that much difference. If it is a progressive they should have done a better job explaining what it is you should be looking at and recording a proper monocular PD.

[@inquisitivenessandcontempl9918]

Hello, an optometrist measured my PD with a pupilometer and at infinity I saw two marks, not like seeing double edges after a night at the bar, but two distinct marks with my each eye. They appeared like two distinct marks right opposite my each eye, at a good distance from one another. I wasn't sure which one I needed to focus on. However, when the optometrist moved the switch to close distance of 40 cm I saw only one mark. After reading about pupilometers I realize I was supposed to be seeing a single mark all the time. Does the fact that I saw two marks mean there is something wrong with my binocular vision, or the pupilometer is malfunctioning? And can I rely on the measurement results? The optometrist didn't notice anything irregular, I told her I saw two marks and she just said I should be focusing on one mark. I've never looked through a pupilometer before and I'm confused. Also, I've never had diplopia as far as I know.

[@LaramyKOptical]

If you look at the pinned comment under the video there is a link out to an article about pupilometers. Quality and construction does differ from the highest end to the direct-from-China ones. Of course the optician will use what they are given by their employer. I feel like I could go on here for an hour ------ if you are uncomfortable with the measurement then try another place preferably one with a modern electronic measuring device. Why was it an optometrist taking your PD since they should get your PD from the phoropter? If your powers are quite high or you are spending $$$$$ on progressives I'd worry a little. If you powers are low and in single vision I wouldn't let it keep me up at night. John

[@inquisitivenessandcontempl9918]

@@LaramyKOptical Thanks a lot for the fast and detailed reply, John. That pretty much solves the puzzle for me. I googled up phoropters, I don't think there are phoropters in the optometrist offices where I live and they were checking my vision with those funny-looking portable frames with interchangeable lenses. The office that had a pupillometer was one of the more well-equipped ones. I probably should find a way to get my vision checked on the more advanced machines, I'll look into that. However for now I'm looking into regular single vision aspheric lenses, my powers are -2.50 and -2.75, so I guess I'll be ok with the ruler measurement.

[@LaramyKOptical]

OK now I have to ask - where do you live?

[@inquisitivenessandcontempl9918]

@@LaramyKOptical I live in Russia, in a predominantly rural area, not in one of the bigger cities/metro areas. Everything tends to be more "old school" over here. They probably do have offices with modern equipment in cities like Moscow or St. Petersburg, but it's not a country-wide standard of care.

[@LaramyKOptical]

@@inquisitivenessandcontempl9918 OK now it all makes perfect sense. I've been to rural Romania so I know what that is like. Rural is rural - even in the US much the same. Where did you learn English? Yours is amazing.

[@DaddyChriis]

I have a question! My PD from my eye doctor wrote 30.75 / 30.75. but online only shows 30.5, is that okay?

[@LaramyKOptical]

Yes. A difference of 1 wouldn't be cause for concern let alone the difference of 0.25 millimeters.

[@DaddyChriis]

Awesome thank you boss!!

[@susmitasuman824]

Sir In bifocal precscripion, near vision pd is written 65. Then what will be near vision pd in separate near vision spectacles?

[@LaramyKOptical]

65 is quite a high near PD but ---- anything made for near would be the same. Within reason anything intermediate would be +2 anything for distance would be +4.

[@susmitasuman824]

@@LaramyKOptical Oh ya Me too doubtful about 65 for near vision. So just now we checked on an IPD application. Long distance PD shows 65 there. I am confused now. Actually i wanna order separate near vision glasses for my dad. He is using bifocal right now & as i said before, his prescription shows near vision pd 65. Should i consider 62 pd for near vision glasses? (65-3=62) Someone told me to reduce 3 from long distance pd.

[@LaramyKOptical]

@@susmitasuman824 3, 4 doesn't matter at all, assuming we aren't talking about +/- 8 or something. If distance is 65 use 62 or 61 whatever you like. 62 is a nice number.

[@susmitasuman824]

@@LaramyKOptical Thank you sir

[@emacina8053]

I want to know about HMC coating ?? Inside the lens

[@LaramyKOptical]

Most any high end AR coating stack will include a hydrophobic layer. There are several videos about those in the library. But - that would be on the lens not in the lens. By definition a coating of any kind is on not in. For a hydrophobic affect it would have to be. See also Quantum Innovations website.

[@robertosfaciosrobka]

You are doing great work here. I'm a customer, and went to a optician chain, and boy, do they leave you with unprecise measurements. A single PD, instead of the one for your right and left eye seperately. They lure you with cheap frames, and then, whem you have found the one that suits you well, they sell you overpriced lenses. Corporations use dirty tactics. I prefere using smaller opticians than chains. People are just unaware of corporate tactics. And at first I thought, small opticians screw me over, but it's the other way around. Unskilled workers they are, not true opticians. Salespeople.

[@LaramyKOptical]

Having worked in both huge corporate and smaller independent places I can say with 100% certainty that you will find good and bad on both sides. Years ago some of the absolute best opticians were at Lenscrafters since sheer numbers alone meant they better know what they were doing. Just find someone you like and trust and shop there. You may find some of other videos helpful too. John

[@ngominh998]

Can this PD meter measure PD for strabismus eyes?

[@LaramyKOptical]

It has an occluder which helps with that. I'm not sure anything can measure for more severe cases of strabismus.

[@RohitSharma-jj2xd]

Hello What would be single vision reading glass ipd, if the if distance ipd is 64?

[@LaramyKOptical]

60 the rule of thumb is minus 4 for near and minus 2 for intermediate. Which is - 2 or - 1 per eye when all is done. Progressives always work off the distance. For all other stuff the 4/2 rule works just fine.

[@RohitSharma-jj2xd]

@@LaramyKOptical Hey Thanks for your reply. Is this for single vision or bifocal?

[@LaramyKOptical]

@@RohitSharma-jj2xd opticianworks.com

[@sphexes]

Terry Gross from NPR

[@LaramyKOptical]

A breath of Fresh Air?

[@Somchine13]

If I have a 30/31, can I convert that to single PD:61?

[@LaramyKOptical]

Sure, but why?

[@Somchine13]

@@LaramyKOptical because I made a mistake ordering glasses online so hoping I don’t have to return them. If it’ll make a difference then I guess I’ll just exchange with the correct dual PD.

[@LaramyKOptical]

I wouldn't worry about it.

[@AmitKumar-cs2jn]

Hi I want to work with you

[@freewithnature]

I’m worried my measurements weren’t proper because I didn’t know what to look at. I saw two circles, one on the right was full the one on the left was kind of obstructed, he just said look threw it 😵

[@lc.f4920]

So why optoms don't give out their pd

[@Ayumu88]

They want you to buy your glasses from them and not online websites like Zenni.

[@sunshinensprinkles9322]

So frustrating. When ordering my very first pair of rx glasses which are progressives. The girl had me look at her nose with both eye and she put a dot in the lenses and then told me to look into the device (pupilometer) right after. She never explained what to do or why and my eyes were still trained looking inward. As she was removing the device it was only then did I catch a glimpse of something colorful in the background. I didn’t say anything. I should have but she just seemed so disinterested in the first place. It’s been 4 days now with my glasses and I’m having the hardest time reading up close. The visual field is at the very bottom inner corner of my glasses and I’m constantly having to move my head up and tilted to read.

[@LaramyKOptical]

Looking at your nose is a technique to force convergence (where your eye is for reading things up close). Any fitting height for a progressive you would want the eye looking in the distance. Or "looking at me." I'm sure that pair is a complete unwearable mess! Sounds like a bad fitting height + a bad PD. RETURN THEM and find a real optician.

[@sunshinensprinkles9322]

@@LaramyKOptical I was afraid of that. Thank you. I will.

[@LaramyKOptical]

@@sunshinensprinkles9322 Might be worth asking for the manager and suggesting they provide their staff a little training. You know more than the "optician" after 40 minutes of watching my videos.

[@sunshinensprinkles9322]

@@LaramyKOptical This is true and the tough thing is, I’m one of those type of people that doesn’t like to make waves. So taking them back and standing up for myself is not going to be the easiest thing for me. Thank you for all your help. Your videos are really very good and helpful.

[@Dackery.]

How about a tutorial on how to recalibrate the pupillometer?

[@LaramyKOptical]

I don't believe that can be done. It is either correct or broken. Although I think Essilor had a check up center at one time but that was 30 years ago now.

[@AG027]

I always have issues with PD because I have lazy eye

[@LaramyKOptical]

Most pupilometers have an occluder which can block off one eye to help with that some. I suppose an electronic measuring device could help. Assuming it is in its "normal" position most of the time using the image from an EMD would let the optician move it to where it should be if the eye is in the "lazy" position. Of course depending on lens powers it might not matter all that much. John

[@MrBsantini]

John: Respectfully, your info about PDs not changing is not an informed and up to date comment.

[@LaramyKOptical]

So you recommend taking a customer PD every time they get a new pair of glasses regardless of their age? Or every other year or every 5 years? Happy to share your thoughts and recommendations. John

[@kellz6266]

i agree. if accuracy matters, you should be double checking PD for every customer, every time. and i would say check their PD, regardless of how low or high their rx is.

[@LaramyKOptical]

@@kellz6266 A man with one watch knows the time. A man with two watches is never sure.

[@LaramyKOptical]

@@Smithy88888 I'm not sure I agree 100% with how you are connecting up the dots, but I sure do agree with you that optometry has an unfair strangle-hold on an entire industry to the detriment of the consumer. But those with the power and the money get to make the rules. Plenty of at home "take your PD" apps out there now.

[@kellz6266]

@@Smithy88888 so my PD is exactly the same as it was when I was 10?

[@ethansugly]

So is near and far Pd just a myth then?

[@LaramyKOptical]

A myth certainly not. Our eyes do converge when we look at something to read. However the difference between our far and near is very consistent so a default of -2 per eye works 99.99% of the time. But like religion or politics others may disagree. John

[@stevehinchey123]

i really value your videos they are clear and concise .However one positive criticism is just wish you would speak in a natural way as your tone sometimes come over as being condescending and you probably are unaware of this . I hope you will not be offended as it is not meant to be an insult .

[@LaramyKOptical]

I love my intended audience and I think our 3.5 million+ views on YT alone prove that. I most certainly do use a condescending tone and even mocking expressions to emphasize that the optician and the opticianry student needs to think independently and know that 95% of the stuff out there on social media is crap. Among my favorite sayings is, "Opticians, their own worst enemy." If I can empower a new generation to think differently they just might have relevance 10 years down the road. If they gobble up the 25-year-old tripe being shoveled out by the same old talking heads of the industry (the very ones that have gotten us nowhere or taken us backwards) then they are doomed for extinction. Someone needs the guts to say, "The Emperor has no clothes on."