Hi Ashutosh,
What should be done is to find a method to improve the brightness of the light emitted by the LEDs. Using ten or hundred LEDs glowing with normal brightness just wont do any good. Glow a single LED with a brigthtness much higher than normally it would glow. It can be done by passing high current through LED, but to prevent the LED from getting damage, restrict this high current period to a few milliseconds only in every seconds.