如何将Google字体.ttf文件转换为其他文件类型以支持所有浏览器

I am going to use 'Open Sans' font. I downloaded the pack from google fonts directory. It has only ttf format files. I want all the file formats(EOT, SVG, WOFF) to support all browser. How to do this.I am going to use 'Open Sans' font. I downloade