Patent ID: 6016376
Filing Date: 2000-01-18
Classification: B82Y,G01Q,G02B

Abstract:
A subwavelength-resolution optical imaging device for conveying light having a wavelength .lambda. emitted, reflected or transmitted by a sample, the device comprising:a coherent fiber bundle comprising a plurality of optical fibers disposed substantially coaxially along their lengths, each optical fiber having a first optical fiber end and a second optical fiber end, and each optical fiber comprising a core having an index of refraction n.sub.1 and a cladding having an index of refraction n.sub.2 thereby providing a value .DELTA., where: ##EQU4## and wherein: the coherent fiber bundle includes an observation end comprising the first optical fiber ends which collectively present an observation end face for at least one of introducing, conveying and emitting the light;the coherent fiber bundle farther includes a sampling end comprising the second optical fiber ends, each second optical fiber end being of reduced diameter in comparison to the first optical fiber end and tapered to present a sampling end face, the core of each optical fiber at the sampling end face having a cross-sectional diameter which is less than or equal to .lambda.; andwherein the values of n.sub.1 and n.sub.2 are selected so as to provide a value for .DELTA. which permits at least a predetermined fraction of the light launched into each optical fiber at the sampling end of the coherent fiber bundle to be conveyed through the optical fiber to the observation end of the coherent fiber bundle and which restricts crosstalk between adjacent optical fibers of the coherent fiber bundle to a predetermined level.