Reducing the memory size of Index for Lucene

I use Lucene for searching the HTML documents. The issue I have is on increased size of index files, I have a开发者_Go百科bt 300-400MB size of HTML files but the index is running upto .98Gb. The reason I see because of specification we have. Like we index the same contents for four different fields, which I guess is the problem ( we use same contents, one case sensitive and other otherwise, one casesensitive with special characters and other otherwise).

Is there a way to reduce the size of index? Keeping the same requirements? Is there a different way we index the same and search differently to support all?

I assume your problem is that you are storing these fields instead of just indexing them. So the solution is: don't store them.