Can you show what you mean, VK? Which shader are you using?

If you make the start angle the same as the end angle, there will be no fading at the edges (as in the image above). I don't know how useful this will be, though. You may be better off using a transparency map.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)