Seyringer, Dana
Refine
Year of publication
Document Type
- Conference Proceeding (60)
- Article (15)
- Part of a Book (2)
- Book (1)
- Habilitation (1)
Institute
Language
- English (78)
- Multiple Languages (1)
Is part of the Bibliography
- yes (79)
Keywords
- Y-branch splitter (9)
- arrayed waveguide gratings (6)
- integrated optics (6)
- OCT (5)
- insertion loss (5)
- Arrayed waveguide gratings (4)
- Optical coherence tomography (4)
- Couplers (3)
- Crosstalk (3)
- MMI splitter (3)
In this work, we present a significant step toward in vivo ophthalmic optical coherence tomography and angiography on a photonic integrated chip. The diffraction gratings used in spectral-domain optical coherence tomography can be replaced by photonic integrated circuits comprising an arrayed waveguide grating. Two arrayed waveguide grating designs with 256 channels were tested, which enabled the first chip-based optical coherence tomography and angiography in vivo three-dimensional human retinal measurements. Design 1 supports a bandwidth of 22 nm, with which a sensitivity of up to 91 dB (830 µW) and an axial resolution of 10.7 µm was measured. Design 2 supports a bandwidth of 48 nm, with which a sensitivity of 90 dB (480 µW) and an axial resolution of 6.5 µm was measured. The silicon nitride-based integrated optical waveguides were fabricated with a fully CMOS-compatible process, which allows their monolithic co-integration on top of an optoelectronic silicon chip. As a benchmark for chip-based optical coherence tomography, tomograms generated by a commercially available clinical spectral-domain optical coherence tomography system were compared to those acquired with on-chip gratings. The similarities in the tomograms demonstrate the significant clinical potential for further integration of optical coherence tomography on a chip system.
We present a new concept of 3D polymer-based 1 × 4 beam splitter for wavelength splitting around 1550 nm. The beam splitter consists of IP-Dip polymer as a core and polydimethylsiloxane (PDMS) Sylgard 184 as a cladding. The splitter was designed and simulated with two different photonics tools and the results show high splitting ratio for single-mode and multi-mode operation with low losses. Based on the simulations, a 3D beam splitter was designed and realized using direct laser writing (DLW) process with adaptation to coupling to standard single-mode fiber. With respect to the technological limits, the multi-mode splitter having core of (4 × 4) μm 2 was designed and fabricated together with supporting stable mechanical construction. Splitting properties were investigated by intensity monitoring of splitter outputs using optical microscopy and near-field scanning optical microscopy. In the development phase, the optical performance of fabricated beam splitter was examined by splitting of short visible wavelengths using red light emitting diode. Finally, the splitting of 1550 nm laser light was studied in detail by near-field measurements and compared with the simulated results. The nearly single-mode operation was observed and the shape of propagating mode and mode field diameter was well recognized.
In this paper, low-loss Y-branch splitters up to 128 splitting ratio are designed, simulated, and optimized by using 2D beam propagation method in OptiBPM tool by Optiwave. For an optical waveguide, a silica-on-silicon material platform is used. The splitters were designed as a planar structure for a telecommunication operating wavelength of 1.55 m. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. The influence of the pre-defined S-Bend waveguide shapes (Arc, Cosine, Sine) and of the waveguide core size reduction on the splitter performance has been also studied. The obtained simulation results of all designed splitters with different S-Bend shape waveguides together with the different waveguide core sizes are discussed and compared with each other.
In this paper, we propose and simulate a new type of three-dimensional (3D) optical splitter based on multimode interference (MMI) for the wavelength of 1550 nm. The splitter was proposed on the square basis with the width of 20 x 20 µm2 using the IP-Dip polymer as a standard material for 3D laser lithography. We present the optical field distribution in the proposed MMI splitter and its integration possibility on optical fiber. The design is aimed to the possible fabrication process using the 3D laser lithography for forthcoming experiments.
We present design and simulation of 16-channel, 100-GHz silicon nitride based AWG using BeamPROP simulation engine of RSoft photonic tool. The AWG was designed for TM-polarized light with central wavelength of 850 nm. The input design parameters were calculated applying AWG-Parameters tool. For this purpose, we created a ridge waveguide structure, used in the design of the AWG layout, and performed FEM simulation. The output of the BPM simulation of AWG structure are the transmission characteristics, which was used to calculate transmission parameters defining optical properties of simulated AWG. The achieved simulation results are in a good agreement with the design.
Design and optimization of 1x2N Y-branch optical splitters for telecommunication applications
(2020)
This paper presents the design and optimization of 1x2N Y-branch optical splitters for telecom applications. A waveguide channel profile, used in the splitter design, is based on a standard silica-on-silicon material platform. Except for the lengths of the used Y-branches, design parameters such as port pitch between the waveguides and simulation parameters for all splitters were considered fixed. For every Y-branch splitter, insertion loss, non-uniformity, and background crosstalk are calculated. According to the minimum insertion loss and minimum non-uniformity, the optimum length for each Y-branch is determined. Finally, the individual Y-branches are cascade joined to design various Y-branch optical splitters, from 1x2 to 1x64.
Comparison of silicon nitride based 8-channel 100-GHz AWGs applying different waveguide structures
(2019)
This paper presents design and simulation of 8-channel, 100-GHz AWGs based on Si/SiO2/SiN/SiOx material platform. For the designs, two different waveguide structures were used, i.e. ridge and rib waveguides. AWGs were designed for central wavelength of 850 nm applying AWG-Parameters tool. The simulations were performed applying FEM and BPM methods in RSoft and PHASAR photonic tools. The simulation results show considerably lower losses but slightly higher channel crosstalk when applying rib waveguides.
Compact and high-resolution 256-channel silicon nitride based AWG-spectrometer for OCT on a chip
(2019)
We present design, simulation and technological verification of a compact 256-channel, 42-GHz silicon nitride based AWG-spectrometer. The spectrometer was designed for TM-polarized light with a central wavelength of 850 nm, applying “AWG-Parameters” tool. This design is based on a previous study of various AWG designs (8-channel, 100-GHz; 20-channel, 50-GHz; 40-channel, 50-GHz, 80-channel, 50-GHz and 160-channel, 50-GHz AWGs), which were all technologically verified. The spectrometer features small size and high resolution. It is integrated on OCT chip using standard CMOS processes. The SD-OCT system is developed to operate in a wavelength range from 800 nm to 900 nm, having 0.1 nm resolution.
