English
norskBlar i forfatter "Helle, Øystein Ivar"
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Chip Based Nanoscopy: Towards Integration and High-throughput Imaging
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017)Super-resolution optical microscopy, commonly referred to as optical nanoscopy, has enabled imaging of biological samples with a resolution that was only achievable previously using electron microscopy. Optical nanoscopy is a rapidly growing field, with several different techniques and implementations that overcome the diffraction limit of light. However, the common nanoscope continues to be a rather ... -
Chip-based optical microscopy for imaging membrane sieve plates of liver scavenger cells
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-08-26)The evanescent field on top of optical waveguides is used to image membrane network and sieve-plates of liver endothelial cells. In waveguide excitation, the evanescent field is dominant only near the surface (~100-150 nm) providing a default optical sectioning by illuminating fluorophores in close proximity to the surface and thus benefiting higher signal-to-noise ratio. The sieve plates of liver ... -
Chip-based wide field-of-view nanoscopy
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-04-24)Present optical nanoscopy techniques use a complex microscope for imaging and a simple glass slide to hold the sample. Here, we demonstrate the inverse: the use of a complex, but mass-producible optical chip, which hosts the sample and provides a waveguide for the illumination source, and a standard low-cost microscope to acquire super-resolved images via two different approaches. Waveguides composed ... -
High-Throughput Total Internal Reflection Fluorescence and Direct Stochastic Optical Reconstruction Microscopy Using a Photonic Chip
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-11-16)Total internal reflection fluorescence (TIRF) is commonly used in single molecule localization based super-resolution microscopy as it gives enhanced contrast due to optical sectioning. The conventional approach is to use high numerical aperture microscope TIRF objectives for both excitation and collection, severely limiting the field of view and throughput. We present a novel approach to generating ... -
Nanoscopy on-a-chip: super-resolution imaging on the millimeter scale
(Journal article; Tidsskriftartikkel; Peer reviewed, 2019-03-04)Optical nanoscopy techniques can image intracellular structures with high specificity at sub-diffraction limited resolution, bridging the resolution gap between optical microscopy and electron microscopy. So far conventional nanoscopy lacks the ability to generate high throughput data, as the imaged region is small. Photonic chip-based nanoscopy has demonstrated the potential for imaging large areas, ... -
On-chip optical nanoscopy: towards high throughput and multi-modality
(Doctoral thesis; Doktorgradsavhandling, 2019-11-07)Super-resolution microscopy techniques improve the resolution of the optical microscope beyond the diffraction limit of light. A range of different techniques demands different optical configurations and clever illuminating strategies to enhance the resolution. This has led to the development of advanced instrumentation, where the super-resolution mechanisms are adding both cost and bulk to the ... -
Optical transport, lifting and trapping of micro-particles by planar waveguides
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-03-03)Optical waveguides can be used to trap and transport micro-particles. The particles are held close to the waveguide surface by the evanescent field and propelled forward. We propose a new technique to lift and trap particles above the surface of the waveguides. This is made possible by a gap between two opposing, planar waveguides. The field emitted from each of the waveguide ends diverge fast, away ... -
Optical Trapping, Levitation and Tracking of Microparticles Using Waveguides
(Master thesis; Mastergradsoppgave, 2014-06-02)Microparticles are trapped by optical forces created by the evanescent field present on the surface of an optical waveguide. An optical waveguide loop with an intentional gap is used to propel and stably hold the trapped particles. The particles are trapped in the gap of the loop by counter-diverging fields. Simulations indicate that particles trapped in the gap on a strip waveguide will be levitated. ... -
Photonic-chip assisted correlative light and electron microscopy
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-07)Correlative light and electron microscopy (CLEM) unifies the versatility of light microscopy (LM) with the high resolution of electron microscopy (EM), allowing one to zoom into the complex organization of cells. Here, we introduce photonic chip assisted CLEM, enabling multi-modal total internal reflection fluorescence (TIRF) microscopy over large field of view and high precision localization of the ... -
Rib waveguides for trapping and transport of particles
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-02-23)Rib waveguides are investigated as an alternative to strip waveguides for planar trapping and transport of microparticles. Microparticles are successfully propelled along the surface of rib waveguides and trapped in the gap between opposing rib waveguides. The trapping capabilities of waveguide end facets formed by a single and opposing waveguide geometries are investigated. The slab beneath a rib ... -
Silicon nitride waveguide platform for fluorescence microscopy of living cells
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017)Waveguide chip-based microscopy reduces the complexity of total internal reflection fluorescence (TIRF) microscopy, and adds features like large field of view illumination, decoupling of illumination and collection path and easy multimodal imaging. However, for the technique to become widespread there is a need of low-loss and affordable waveguides made of high-refractive index material. Here, ... -
Structured illumination microscopy using a photonic chip
(Journal article; Tidsskriftartikkel; Peer reviewed, 2020-04-11)Structured illumination microscopy (SIM) enables live-cell super-resolution imaging of subcellular structures at high speeds. At present, linear SIM uses free-space optics to illuminate the sample with the desired light patterns; however, such arrangements are prone to misalignment and add cost and complexity to the microscope. Here, we present an alternative photonic chip-based two-dimensional SIM ...
