Spectacular results on breast cancer with Peking University Peoples Hospital
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Bertrand de Poly Jury for Les Echos E-Health 2018 Award
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LLTECH laureate of the ECARE tour 2018
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Meet us at BIO 2018
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LLTech at Photonics West 2018 – 27 January – 1 February 2018
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Full field OCT, the principle behind LLTech devices, performs non-invasive high-resolution optical slicing beneath the tissue surface.

The full field approach offers great potential in imaging of samples to assist fast diagnosis of cellular and morphological scale pathologies, such as cancer.
The schematic below illustrates the full-field OCT principle. It is essentially an interference microscope (i.e. a regular microscope with an added reference arm) or more precisely a classic Michelson interferometer with a microscope objective in each arm.


Light-CT captures “en face” images directly using a megapixel camera and a pair of microscope objectives.
Light-CT derives from low coherence interference microscopy. The interferometer can be displaced to step the focal plane through different depths beneath the surface to create a 3D tomographic image. “En face” capture allows Light-CT to operate with high lateral resolution (typically ~1µm) using medium or large aperture microscope objectives.

An incoherent light source illuminates the whole field of the microscope objectives. Due to the low temporal coherence of the source, interference occurs only when the optical path lengths of the two arms of the interferometer are identical within 1µm.
When a biological sample is placed under the microscope objective in the sample arm, the light reflected by the reference mirror interferes with the light reflected or backscattered by the sample structures contained in a limited volume. The Light-CT fine slicing ability allows depth exploration and high-quality 3D imaging.

The FFOCT image displays in gray scale the static optical contrast of the region of interest. Hihgly backscattering content like different fibrous structures (collagen, axons, etc.) appears white while weakly backscattering content like cells appears dark gray or black.