Rx Compensator v2.6 (International friendly)

[Darryl Meister]

This is the latest build of a lens tilt and vertex distance compensation program written in Visual Basic by Darryl Meister. This program utilizes 'thin' lens approximations for single vision lens tilt compensation. More precise results may be obtained by software employing exact ray-tracing methods, such as those used for SOLA's Spazio lenses. This program is intended for educational purposes only. Always use professional judgment when interpreting these results, particularly when evaluating unusual combinations of prescription power, frame geometry, or lens tilt.

The latest version contains a small enhancement to support multi-region number formats (i.e., the use of commas instead of periods for decimal points).

Rx Compensator v2.9 (http://www.opticampus.com/files/rx_compensator.zip)

[alberto_correia]

Works great. Now RxCompensator as made International. "Another nail towards perfection". Many thanks.

[Darryl Meister]

Here is a basic frame protractor that you can use to estimate face form wrap.

[alberto_correia]

Thanks. It will be very usefull.

[Grubendol]

That is great, I already have it attached to my desk!

[OpticalNinja]

For some reason I can't the program to install, I keep getting this message:
Class not registered, you need the following to be installed on your machine: MSSTDFMT.DLL

Thanks in advance

[OpticalNinja]

Sorry disregard that^^^^

I used my Ninja hacking skills to get it to work

[Darryl Meister]

Yeah, I didn't include any additional DLL files with the program, since the stuff I used should come standard in most Windows operating systems. Otherwise, I can create a full-blown installation program that will install any missing Windows files.

[uberoptiker]

Greetings. I have noticed that this program is set up with the baseline settings at zero degrees for both panto and wrap. While technically correct (the phoropter has no face-form or panto), we don't alter the prescription when we make conventional eyeglasses that would usually have 5-10 degrees of face-form, and 10-15 degrees of panto. When we enter a prescription of say, -4.00 -1.00 x95 and enter 7.5 degrees of face form, and 15 degrees of panto, made in 1.67 with a 50mm lens, we get -3.62 -1.12 x87. Even if we round to the quarter diopter closest to the original prescription, we are still .25 too weak in the sphere, and 8 degrees off in the cyl. Now perhaps in a perfect world this would be done to all eyeglasses to compensate for the geometrical difference between a phoropter, and an eyeglass frame, but does this not meen that when we are making sunglasses for a patient, we are giving them a bigger bridge to cross when going between their regular eyeglasses and their compensated sunglasses? I have to admit I've had a number of patients bring their glasses back after being made with this compensation program. Admittedly, at my office, we do keep our patients in their native base curve, and will put a 2-base lens into a wrapped frame (we have some pretty funky edging capabilities due to the owner hot-rodding the edgers), but I feel that would just make the adjustment easier, and shouldn't matter to the program anyway, as there is a field to enter in the base curve of the lens being used...
Any thoughts?

[Darryl Meister]

Greetings. I have noticed that this program is set up with the baseline settings at zero degrees for both panto and wrap.
It's set at zero for these values simply because it doesn't making any assumptions about the fit of any particular wearer's frame. Also, any value other than zero might encourage users to sidestep taking the actual measurements--assuming that the "default" values are correct instead. If your phoropter (or perhaps trial frame) is tilted, then the tilt used in the program should be adjusted accordingly.

When we enter a prescription of say, -4.00 -1.00 x95 and enter 7.5 degrees of face form, and 15 degrees of panto, made in 1.67 with a 50mm lens, we get -3.62 -1.12 x87...we are giving them a bigger bridge to cross when going between their regular eyeglasses and their compensated sunglasses?
The program is just compensating for the fact that tilting a -4.00 D lens 15 degrees increases the sphere power (by a very predictable amount). The prescription (not necessarily any other variables) experienced by the wearer using this prescription in a frame with 15 degrees of pantoscopic tilt should be very similar to the prescription experienced by the wearer using his or her original prescription in a frame with no tilt.

I have to admit I've had a number of patients bring their glasses back after being made with this compensation program.
You would have to supply some specific examples, including the chief wearer complaints, in order for me to respond to this. Keep in mind that this program is only designed to improve the accuracy of the prescription through the center of the lens when prescription is worn in a tilted configuration. There are other factors involved that may also affect visual performance and patient acceptance, including the design of the lens or Base curve configuration.

[LM Wong]

Sorry to say that I have no Ninja hacking skills.
I am not able to open the file as I'm missing the MSSTDFMT.DLL file.
Is there some way to get this missing file so that I can access this program?

[Bobie]

Thank you for good software and good picture , Darryl. :p

[Freedom]

THANK YOU.

[Cowboy]

Isn't it wonderful that we live in a world where almost everything is at your fingertips with fantastic technology? However, we lose our brains! We are left for something or even someone to think for us. But, I guess I am being hipocritical considering that I am using a technological means of contact to get an answer that will allow me to use my brain. So here is the question - Where can I find the actual printed formula(s) so that I can see and apply the equations for rx/prism compensation in high wrap/tilt sunwear/eyewear?

Thanks for any input you can download so that I can upload and then hand calculate!

Cowboy
:hammer: :cheers: :shiner:

[Darryl Meister]

If you do a search over in the Ophthalmic Optics forum, a couple of threads should turn up that discuss this in detail.

[ego]

I have a question about fitting the lenses into the frame after producing lenses with the new power
How should I edge them and then fit them to the frame ?
I do it like that ,I mark the produced lenses on the new power that i had from the RX compensator,then block it and then edge the lens so that the new power will be in the midle of the frame (by the frame PD )
Want to know if this is right or there is some other way.
Can you help me with drawings or presentation
Thanks
Ego