Visible Gyroid infill is nice on a lamp shade, no direct light in your eyes. Remix your own cap, e.g. pear leaf'd.
If you dont know how to slice..
Open Slic3r (Prusa 1.4.1+)
Print settings Perimiters: 0 Solid Layers: 0 Infill: Gyroid. In my pics it is printed at 20%
Add the shade model Right click it and then settings
Load gyroid part by clicking Load part..
Select shade model, click the plus and choose perimiters - set it to e.g. 4 Add top solid layers and add bottom layers, set both to e.g. 5
Add infill pattern