René P Salathé

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Comparison of two illumination modes for wide-field optical coherence tomography has revealed that spatially coherent illumination generates coherent cross talk, causing significant image degradation, and that spatially incoherent illumination, with an adequate interferometer design, provides an efficient mechanism for suppression of coherent cross talk.(More)
A low-coherence reflectometer based on a conventional Michelson interferometer and a novel silicon detector chip with a two-dimensional array of pixels that allows parallel heterodyne detection is presented. We demonstrate acquisition of three-dimensional images with more than 100,000 voxels per scan at a sensitivity of -58 dB and a rate of 6 Hz.
A superluminescent Ti:Al2O(3) crystal is demonstrated as a light source for ultrahigh resolution optical coherence tomography (OCT). Single spatial mode, fiber coupled output powers of ~40 microW can be generated with 138 nm bandwidth using a 5 W frequency doubled, diode pumped laser, pumping a thin Ti:Al2O(3) crystal. Ultrahigh resolution OCT imaging is(More)
Most current optical coherence tomography systems provide two-dimensional cross-sectional or en face images. Successive adjacent images have to be acquired to reconstruct three-dimensional objects, which can be time consuming. Here we demonstrate three-dimensional optical coherence tomography (3D OCT) at video rate. A 58 by 58 smart-pixel detector array was(More)
A strong axial tension increase induced by UV laser radiation is observed in the cores of single-mode optical fibers containing Bragg gratings, independently of the initial core stress. The induced index modulation of the gratings is linearly correlated to stress changes with a slope of (0.8 +/- 0.2) x 10(-4) mm(2)/kg. The phenomenon can be explained by a(More)
Optical low-coherence ref lectometry is applied for the first time to our knowledge to investigate diffusive biological tissues with a single-mode fiber probe. Samples of fresh arteries are studied, using the backscattered light from the tissue. The probed volume in the vicinity of the fiber tip is estimated to be below 6.7 x 10(-10) cm(3). This noninvasive(More)
We show strong changes in chemical etching of phosphorus-doped fiber cores due to hydrogen loading and subsequent UV-irradiation using an atomic force microscope. The etch rate of the fiber core in a low concentration hydrofluoric acid solution (HF) is decreasing after hydrogen loading by as much as 30%. In contrast, UV-irradiation of the hydrogenated fiber(More)
A simple method for the calibration of optical path difference modulation in low-coherence interferometry is presented. Spectrally filtering a part of the detected interference signal results in a high-coherence signal that encodes the scan imperfections and permits their correction. The method is self-referenced in the sense that no secondary(More)
We demonstrate the suitability of a simple continuous-wave-pumped transition-metal-ion-doped waveguide as a broadband light source in the wavelength region 600-1000 nm for interferometric applications. Spatially coherent (single mode in the confined direction), spectrally broadband (~130-nm FWHM) luminescence with output powers of several hundreds of(More)