How can i focus two or more (infra red) led's into one tight beam? Thanks

This would be for a laser tag gun, more than one infra red LED could greatly improve distance (so it is theorized) but if you think it wouldn't, give us a yell. How it normally works in the gun, is a high powered infrared LED with an already tight beam of about 20 degrees is projected onto a double convex lense about 2 to 5 cm in diameter. The beam is focused by moving the LED back and forwards with snipers having tight beams for the longest range and others having very wide beams to limit range and but improve accuracy at close range. Any help is much APPRECIATED. OH and someone recommended a cube beam splitter but i have no idea what they are so you may want to look them up... THANKS COMMUNITY

hey, me and my friends are building laser tag guns. we're going to put one LED surrounded by four others in the gun and then focus them as shown by the image. that's how we'ere going to make snipers and the rest of the guns will be made using normal focusing.
hope this helps :)
ps where are you getting the parts for the tag guns?
laser tag.jpg