It sounds like your email is compressing the file when it sends.
First, I'd look at the screenshots in your camera roll on the iPad. If they look blurry there, then that would be something else to think about. If they look fine, and you can zoom in with your fingers to see it, I'll say it's the email.
Are you using the Mail app on the iPad? When I attach a photo using Mail, it'll ask if I want to send it as the full image or a smaller files. If you're getting this message, choose "Actual Size" and it shouldn't be compressed.