Hi Rose, 

I believe you contacted us via email about this, but let me answer here as well just in case other people have the same problem. First of all, thank you for checking out our Knowledgebase Article on the Human eye!

The reason why we see a line in the Layout is because Surface 0 is something like 1.00E+009. This is a large number, and the Layout is displaying that distance as well. This Human eye model is one of our older articles, and was originally made in Zemax (the software, our product that evolved into OpticStudio). There is an old setting in Zemax where infinity equaled 1.00E9. Now, it is 1.00E10.

There are two ways to fix the layout in this model.

1. The display of the 3D layout “First Sufrace” is 0, but if you set it to “1” you should get the right image.

2. Alternately, you can change the Thickness of Surface 0 to “infinity” and click “reset zoom” as well. 1.00E+9 and 1.00E+10 won’t give you any measurable differences in the results.