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Optical sectioning structured illumination microscopy (OS-SIM) provides optical sectioning capability in wide-field microscopy. The required illumination patterns have traditionally been generated using spatial light modulators (SLM), laser interference patterns, or digital micromirror devices (DMDs) which are too complex to implement in miniscope systems. MicroLEDs have emerged as an alternative light source for patterned illumination due to their extreme brightness capability and small emitter sizes. This paper presents a directly addressable striped microLED microdisplay with 100 rows on a flexible cable (70 cm long) for use as an OS-SIM light source in a benchtop setup. The overall design of the microdisplay is described in detail with luminance-current-voltage characterization. OS-SIM implementation with a benchtop setup shows the optical sectioning capability of the system by imaging within a 500 µm thick fixed brain slice from a transgenic mouse where oligodendrocytes are labeled with a green fluorescent protein (GFP). Results show improved contrast in reconstructed optically sectioned images of 86.92% (OS-SIM) compared with 44.31% (pseudo-widefield). MicroLED based OS-SIM therefore offers a new capability for deep tissue widefield imaging.

We demonstrate a two photon (2P) fiber STED microscope in which the excitation and STED light are delivered to the sample in polarization maintaining (PM) fiber.

The DyMIN method reduces photobleaching, a problem in STED microscopy. Labs implementing custom-built STED microscopes would greatly benefit from DyMIN capabilities. We present an inexpensive, open-source version utilizing an FPGA and multiplexer.

A diode-based time lens laser with nonlinear pulse compression at 976 nm produces 700 fs pulses with 17 kW peak power. Two-photon imaging of a mouse brain slice is demonstrated with the laser.

We present widefield structured illumination in a miniature, light-weight fiber-coupled microscope with electrowetting axial scanning. We demonstrate imaging of YFP-labeled neurons in mouse brain tissue showing potential for fast volumetric imaging in freely moving animals.

We demonstrate a near-infrared, femtosecond, diode laser-based source with kW peak power for two-photon microscopy. At a wavelength of 976 nm, the system produces sub-ps pulses operating at a repetition rate of 10 MHz with kilowatt class peak powers suitable for deep tissue two-photon microscopy. The system, integrated with a laser-scanning microscope, images to a depth of 900 µm in a fixed sample of PLP-eGFP labeled mouse brain tissue. This represents a significant development that will lead to more efficient, compact, and accessible laser sources for biomedical imaging.