Patent ID: 7113669
Filing Date: 2006-09-26
Classification: G11B

Abstract:
1. A near field light head comprising: a board; a light waveguide for introducing propagated light from a light source; and a near field light generating element for converting the propagated light into near field light, wherein the board has the near field light generating element at a first face thereof, and has the light waveguide on a second face thereof on a side opposed to the first face, and the light waveguide comprises a first light waveguide connected to the light source, a second light waveguide a refractive index of which is changed continuously from a center thereof in a direction of a side face thereof and a third light waveguide a refractive index of which is uniform, the first light waveguide, the second light waveguide and the third light waveguide are coaxially arranged in this order, and an end face of the third light waveguide opposed to an end face thereof opposed to the second light waveguide includes a reflecting face for guiding the propagated light to the near field light generating element.