Here you go, enjoy! These were made with a Spyder3 and dispcalGUI. I've also used ColorEyes Display Pro and it gives very similar results, but the consistency in the dark gray tones is not as good.
Some important info about these profiles: the first link is a very precise LUT-based profile combined with an inverted matrix-based profile. I'd recommend most of you don't use this profile unless you understand color management. If you use this profile with a program that does not support XYZ-LUT profiles, then it will show the colors as inverted (ex. Windows Photo Viewer). The is done intentionally because it lets you know it's not using the more-accurate LUT-based profile and is instead using the less-accurate matrix based profile (which is the color-inverted profile). However, using this profile with a truly color-managed app like Photoshop or Lightroom will yield very, very nice results. White point 6500K/D65, gamma 2.2.
https://www.dropbox.com/s/hmdbau8c32y5yt9/dispcalGUI%20ThinkPad%20Display%201920%202012-04-30%20D650...
This second profile will work acceptably with most programs. It's not quite as extremely accurate as the first, but still very good. The gamma curve for this profile is L* instead of 2.2, which I prefer for most normal use, because it lessens the "black crush" at the bottom of the gamma curve and makes shadow details more visible. White point, again, is 6500K/D65.
https://www.dropbox.com/s/ruyk59sqdu7orbe/dispcalGUI%20ThinkPad%20Display%201920%202012-04-30%20D650...
If you don't know how to have Windows load these for you:
-First, copy the profiles to C:\Windows\System32\spool\drivers\color (this is where Windows stores color profiles for devices). Or, you can simply right-click on the files and select "Install Profile"... but we're not done yet.
-Next, go to Control Panel > Color Management
-Make sure at the top, next to Device, it says "Display: 1. ThinkPad ..."
-Put a check mark in the box that says "Use my settings for this device"
-In the box under "Profiles associated with this device," you may or may not see the profiles I gave you (they start with "dispcalGUI Thinkpad Display ...") If they are not listed, click "Add..." and select them from the list, click Ok.
-Now, find the one you want to use (for most I'd recommend "dispcalGUI ThinkPad... HQ 3xCurve+MTX"), click on it to highlight it, then click "Set as Default Profile"
-Now, click the "Advanced" tab at the top, and down at the bottom, click "Change system defaults..." In the new window that pops up, click the Advanced tab again (Don't change anything else!)
-Put a check in the box that says "Use Windows display calibration," click "Reload current calibrations" and then click close on all the windows
You should have seen the screen change slightly, and the display profile is now loaded. Windows will now load it automatically on its own.
One last important bit of advice: one of the Intel processes that runs on the W520 will un-load the display calibrations whenever the screen darkens for a Windows UAC prompt, or after coming back from sleep. Instructions for fixing that are here: http://forums.lenovo.com/t5/W-Series-ThinkPad-Laptops/w520-color-calibration-issue/td-p/728457
EDIT: forgot to add, one last thing, this is very important: go to start, type in msconfig, click the "Startup" tab, and UN-CHECK "X-RITE Legacy Device," "CalibrationLoader5.0," AND "Color Calibrator Tray." Click apply, then ok. These are the processes associated with the built-in color sensor, if you have it, and they may interfere with Windows loading the profiles.
Josh
