The inherent problem in designing Japanese fonts is the sheer quantity of characters – 50,000 compared to 26 for their latin counterpart – and the labor involved. This perhaps justifies why many Japanese fonts are so expensive. But there are a few free fonts out there. Below are a mix of Japan-influenced roman fonts and actual Japanese fonts.
A solid font that is free and comes with very few restrictions. It was designed by graphic designer Atsushi Kawakami and was just released on Jan 5, 2012. And with an English interface downloading it couldn’t be easier.
This is a cute handwriting font. Although the Miura font family is not free, Mop Studio has released a free version called Miura Liner Jr. The caveat is that it only contains 450 kanji characters (click for full list), enough for some basic writing but probably not enough for that dissertation you’re working on. The Japanese interface is a bit difficult to navigate so here are the download links for Mac and Windows.
The M+ fonts are quite beautiful. They’re free and feature proportional and fixed-halfwidth Latin, as well as fixed-fullwidth Japanese. Here is the English interface when you can download from.