Chip-based wide field-of-view total internal reflection fluorescence microscopy

Abstract

Conventional total internal reflection fluorescence (TIRF) microscopy requires either an oil-immersed objective with high numerical aperture or a bulky prism with high refractive index to generate the evanescent waves that work as the illumination source for fluorophores. Precise alignment of the optical path is necessary for optimizing the imaging performance of TIRF microscopy, which increases the operation complexity. In this Letter, a planar photonic chip composed of a dielectric multilayer and a scattering layer is proposed to replace the TIRF objective or the prism. The uniform evanescent waves can be excited under uncollimated incidence through this chip, which simplifies the alignment of the optical configurations and provides shadowless illumination. Due to the separation of the illumination and detection light paths, TIRF microscopy can have a large field-of-view (FOV).

Planar photonic chips with tailored dispersion relations for high-efficient spectrographic devices

“…The combination of the multilayer-chip and the prism work as a flexible coupler that can converts freespace light to localized surface waves propagating on the top surface of this photonic chip. The localized electromagnetic surface waves known as Bloch surface waves (BSWs), are extremely sensitive to the environmental changes and also the incident wavelengths, which have been widely used in the field of imaging and sensing and integrated photonic elements 41,42,43,44,45,46,47,48,49,50 . Similar structure combining metallic particle or metallic layer have been used to retrieve the optical spectra, unveiling a new type of design for micro spectrometer 25,31 .…”

Concentration monitoring through a refractive index compass based on metasurface

“…Miniaturization of devices allows for high integration with other functional modules, resulting in comprehensive analysis systems and enabling portable or remote monitoring in micro laboratories and biomedical diagnostics. [1][2][3] The conventional bulky components of refractive index detecting have now been replaced with nanophotonic materials, which have been fabricated by metasurfaces, [4][5][6][7][8] photonic crystals, [9][10][11][12][13][14] plasmonic structures, [15][16][17][18] microsphere resonance system, 19,20) and topological photonics. 21,22) These micro structures and materials exhibit high sensitivity to external refractive index variations, with most of them able to achieve sensing of refractive index through the resonance peaks moving.…”