Mix all ingredients in a medium bowl. DO AHEAD Can be made 1 day ahead. Cover and chill.

Put noodles in a large bowl. Pour enough hot water over to cover; let stand until softened, about 10 minutes. Drain. Transfer to a large bowl of ice water to cool; drain and set aside.

Fill a pie plate with warm water. Working with 1 rice paper round at a time, soak rice paper in water, turning occasionally, until just pliable but not limp, about 30 seconds. Transfer to a work surface. Arrange 3 shrimp halves across center of round. Top with some leaves of each herb, then daikon sprouts (if using), cucumber, and carrot. Arrange a small handful of noodles over. Place 1 lettuce leaf over, torn or folded to fit. Fold bottom of rice paper over filling, then fold in ends and roll like a burrito into a tight cylinder. Transfer roll, seam side down, to a platter. Repeat to make 11 more rolls. DO AHEAD Can be made 1 hour ahead. Cover with a damp kitchen towel and refrigerate.

To serve, cut rolls in half on diagonal. Add chopped cilantro to dipping sauce.

Yield: 12