Pixelated type in only certain browsers

I’m using the Platform theme which gives a choice of fonts. My other fonts look fine, but Courier looks seriously pixelated in the Firefox and Explorer browsers. It looks fine in Google Chrome. Why, and how can I fix it?
http://www.courtneydruz.com

[duplicate: http://ww.wp.xz.cn/support/topic/fonts-in-platform-132-theme-pixelization-of-courier?replies=2 – please start only one topic per problem, and continue with your original thread – topic closed]