Patent ID: 6377535
Filing Date: 2002-04-23
Classification: B82Y,G02B,G11B

Abstract:
An optical data storage system comprising:an optical focusing device for focusing an incident optical beam to a focal spot, comprising: a top surface comprised of a peripheral reflector and a central facet upon which the optical beam impinges; a body through which the incident optical beam passes; a bottom reflective surface for reflecting the optical beam through said body toward said peripheral reflector; a pedestal extending from said bottom reflective surface for defining a focal plane on which the focal spot is formed; said peripheral reflector focusing the optical beam reflected from the bottom reflective surface to the focal spot; and said central facet being generally conically shaped; wherein the beam is any of: a collimated, convergent, or divergent beam; wherein said central facet refracts the incident optical beam away from said pedestal, onto said bottom reflective surface; wherein said central facet is optically refractive; and wherein the incident optical beam is refracted by said central facet as a generally collimated beam with a donut shaped cross-section.