Patent ID: 7085467
Filing Date: 2006-08-01
Classification: B82Y,G02B

Abstract:
1. A three-dimensional periodic structure exhibiting a photonic band gap comprising: a first layer including a plurality of square columns spaced apart by a predetermined interval; a second layer including a plurality of square columns spaced apart by a predetermined interval, the square columns extending in a direction different from that of the square columns in the first layer; a third layer including a plurality of square columns spaced apart by a predetermined interval, the square columns extending in the same direction as that of the square columns in the first layer; a fourth layer including a plurality of square columns spaced apart by a predetermined interval, the square columns extending in the same direction as that of the square columns in the second layer; and additional layers, each including one layer containing rectangular parallelepipeds disposed discretely in a plane parallel to each of the first, second, third, and fourth layers, wherein the first, second, third and fourth layers are stacked sequentially with the additional layer therebetween, the first layer and the third layer are stacked such that the square columns contained in the first and third layers mutually shift by one-half the predetermined interval in a direction perpendicular to the direction of the extension of the square columns, the second layer and the fourth layer are stacked such that the square columns contained in the second and fourth layers mutually shift by one-half the predetermined interval in a direction perpendicular to the direction of the extension of the square columns, rectangular parallelepipeds contained in the additional layers are disposed at positions corresponding to intersections of the square columns, the square columns contained in the first, second, third and fourth layers and the rectangular parallelepipeds contained in the additional layers are formed from a first medium, regions contained in the first, second, third and fourth layers other than the square columns and regions contained in the additional layers other than the rectangular parallelepipeds are formed from a second medium having a refractive index lower than that of the first medium, when the length of one side of the rectangular parallelepiped contained in the additional layer is assumed to be W is satisfied, and when the length of the other side perpendicular to the side having a length of W is satisfied.