Physics

Channel (broadcasting)

Lens (geology)

Chip

Spatial light modulator

Optics

Total internal reflection fluorescence microscope

Computer graphics (images)

Microscopy

Planar

Total internal reflection

Numerical aperture

Materials science

Waveguide

Photonics

Optical path

Interference (communication)

Computer science

Optoelectronics

Wavelength

Microscope

Telecommunications

Nature Photonics

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 approach (cSIM) in which the conventional glass sample slide in a microscope is replaced by a planar photonic chip that importantly both holds and illuminates the specimen. The photonic chip reduces the footprint of the light illumination path of SIM to around 4 × 4 cm2. An array of optical waveguides on the chip creates standing wave interference patterns at different angles, which illuminate the sample via evanescent fields. High-refractive-index silicon nitride waveguides allow a 2.3 times enhancement in imaging spatial resolution, exceeding the usual 2 times limit of SIM. In summary, cSIM offers a simple, stable and affordable approach for performing two-dimensional super-resolution imaging over a large field of view. The use of a photonic integrated circuit to both hold a biological sample and generate the necessary light patterns for structured illumination microscopy promises convenient super-resolution imaging.

Structured illumination microscopy using a photonic chip