11. The complete interference pattern takes the appearance of a set of concentric rings . 12. These are concentric rings of lipid and protein, about 1 �m in diameter. 13. The clock's face is a rippling concentric rings displaying hours, minutes, and seconds. 14. Each 80 x 65 cm surface contains three concentric rings . 15. The Acuvue lenses have five concentric rings that alternately correct near or far vision. 16. In butterflies, the spots are composed of concentric rings of scales of different colours. 17. The crater displays several concentric rings and radial faults, and an eroded central bulge. 18. Law enforcement always looks at providing three concentric rings of security for big events, 19. Concentric ring fractures formed around the volcano, creating convenient conduits for additional volcanic vents.20. In 1994, a new roundel was introduced, featuring the national colours in concentric rings .
