Focusing multimodal optical microprobe devices

Abstract

The present invention provides an optical microprobe device and method for focusing multimodal radiation with wavelength-scale spatial resolution and delivering the focused radiation to a specimen, including: a radiation source; and one or more of a plurality of optically transparent or semitransparent spheres and a plurality of optically transparent or semitransparent cylinders optically coupled to the radiation source; wherein the one or more of the plurality of optically transparent or semitransparent spheres and the plurality of optically transparent or semitransparent cylinders periodically focus radiation optically transmitted from the radiation source such that radiation ultimately transmitted to the specimen has predetermined characteristics. Preferably, the spheres or cylinders are assembled inside one of a hollow waveguide, a hollow-core photonic crystal fiber, a capillary tube, and integrated in a multimode fiber. Alternatively, the spheres or cylinders are assembled on a substrate. Optionally, the optical microprobe device also includes one or more of a waveguide, an optical fiber, a lens, and an optical structure disposed between the radiation source and the spheres or cylinders. Optionally, the spheres or cylinders are made from optically nonlinear or active materials that permit efficient nonlinear frequency generation and low-threshold lasing using the optical microprobe device.