I am using the "Helvetica Neu LT 35 Thin" (ttf format) which is looking great on my website (iOS) but horrible and distorted when the website viewed on windows. I heard that otf is better for web so I used an online converter to convert the font to OpenTypeFont (http://www.freefontconverter.com/), I did help a bit bu the ugly distortion is still there.
How can I solve this problem? and whats causing it?.
PS: the font look great in Photoshop in both cases
You may try to use Clear Type if not already. Depending on Windows version you may get to it by something like:
Right click on the screen, then click Properties, and in Display Properties click Appearance>Effect and tick Use the following option to smooth edges of screen fonts, in the dropdown tick Clear Type instead of Standard.