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kwon0504
04-02-2007, 11:58 PM
Thought some of you might be interested in this calculator I developed to determine lens thickness.

Sung S. Kwon

alberto_correia
04-03-2007, 06:22 AM
Gotta be kinding me! :-O Undoubtely one of the best I ever seen. Congratulations. I are worth of it.

HarryChiling
04-03-2007, 07:11 AM
Very Nice, thanks.

Rafael
04-03-2007, 04:04 PM
Looks very good. Thank You very much.

But I need you help, why i get results only for minus lenses and plano?

Rafael

specs4you
04-04-2007, 03:33 AM
Would love to see your calculations, apparently it only is able to open with Excel format, which unfortunately I don't have. Any other way to send it?
Can you open it and and send as an attachment to me in e mail, would that work. Any ideas Opti friends?

Thirsty for knowledge.

HarryChiling
04-04-2007, 08:39 PM
specs4you,

you can download and install openoffice which is a free version of the office programs. www.openoffice.org (http://www.openoffice.org) they have a spreadsheet program that will open excel files.

specs4you
04-05-2007, 01:32 AM
thanks a heap.......have a great day all......specs4you,

you can download and install openoffice which is a free version of the office programs. www.openoffice.org (http://www.openoffice.org) they have a spreadsheet program that will open excel files.

kwon0504
04-05-2007, 02:08 AM
Looks very good. Thank You very much.

But I need you help, why i get results only for minus lenses and plano?

Rafael

I revised the calculator in response to Rafael's comment. Good point, thanks.

Rafael
04-05-2007, 06:10 AM
Thank you again,

if you have time do fix the follow points, it would be great:

a) for minus lenses if i set the ct it calculates acurate,
but if i put the et for plus lenses i get wrong results.
The set edge thickness = the centerthickness.
Would be fine if the programm can calculate the Ct, or even better
the thickess on radius and axis, we can choose.

b) Please check the input for the cylinder, on minus lenses the calculations works only if the cylinder is put in (-) Value.

On plus lenses the calculation with cylinder doesent work, for (+) and for (-) value.

Would be fine if both combinations are possible for the data entry.


Rafael

kwon0504
04-05-2007, 12:59 PM
Thank you again,

if you have time do fix the follow points, it would be great:

a) for minus lenses if i set the ct it calculates acurate,
but if i put the et for plus lenses i get wrong results.

Rafael

The formulas calculate the center thickness of the lens for plus lenses.
Therefore, the Lens Thickness Graph will show you the center thickness
no matter what axis it is.
If you have (+) Sph with (+)Cyl, the program will calculate the
strongest power after transposing. For example, if you selected the Rx =
+3.00 +1.00 x 180, it will calculate the thickness with the power of
+4.00 D and the longest distance from OC.

Hopefully, that helps. Thanks.
Sung

PSI
04-17-2007, 10:52 AM
Hi ,

I appreiciate your work. But this index thickness is only pertaining to a 1.5 index right what if the patient wants to know at the higher index's that is 1.67/1.7/1.8 and 1.9 then how can we calculate the thickness value using your calculator.

PSI

kwon0504
04-17-2007, 09:06 PM
Hi ,

I appreiciate your work. But this index thickness is only pertaining to a 1.5 index right what if the patient wants to know at the higher index's that is 1.67/1.7/1.8 and 1.9 then how can we calculate the thickness value using your calculator.

PSI

Click on the "Lens Material" dropdown box to select the lens material you want to use or check. For high index, I added 1.60, 1.67, 1.70, 1.74, 1.80, and 1.90. It also includes CR39, Crown Glass, Trivex(1.532), Spectralite, Alphalite, 1.56 Mid-Index, and Ploycarbonate lenses.

Sung