Low-cost 3D printed lenses for brightfield and fluorescence microscopy.

We present the fabrication and implementation of low-cost optical quality 3D printed lenses, and their application as microscope objectives with different prescriptions. The imaging performance of the 3D printed lenses was benchmarked against commercially available optics including a 20 mm focal length 12.7 mm diameter NBK-7 plano-convex lens used as a low magnification objective, and a separate high magnification objective featuring three 6 mm diameter NBK-7 lenses with different positive and negative focal lengths.

Miniaturized structured illumination microscopy using two 3-axis MEMS micromirrors.

We present the development and performance characterisation of a novel structured illumination microscope (SIM) in which the grating pattern is generated using two optical beams controlled via 2 micro-electro-mechanical system (MEMS) three-axis scanning micromirrors. The implementation of MEMS micromirrors to accurately and repeatably control angular, radial and phase positioning delivers flexible control of the fluorescence excitation illumination, with achromatic beam delivery through the same optical path, reduced spatial footprint and cost-efficient integration being further benefits. Our SIM architecture enables the direct implementation of multi-color imaging in a compact and adaptable package.

Cold-atom shaping with MEMS scanning mirrors.

We demonstrate the integration of micro-electro-mechanical-systems (MEMS) scanning mirrors as active elements for the local optical pumping of ultra-cold atoms in a magneto-optical trap. A pair of MEMS mirrors steer a focused resonant beam through a cloud of trapped atoms shelved in the F = 1 ground-state of Rb for spatially selective fluorescence of the atom cloud. Two-dimensional control is demonstrated by forming geometrical patterns along the imaging axis of the cold atom ensemble.

MEMS enabled miniaturized light-sheet microscopy with all optical control.

We have designed and implemented a compact, cost-efficient miniaturised light-sheet microscopy system based on optical microelectromechanical systems scanners and tunable lenses. The system occupies a footprint of 20 × 28 × 13 cm and combines off-the-shelf optics and optomechanics with 3D-printed structural and optical elements, and an economically costed objective lens, excitation laser and camera. All-optical volume scanning enables imaging of 435 × 232 × 60 µm volumes with 0.

Recent advances in optical fiber devices for microfluidics integration.

This paper examines the recent emergence of miniaturized optical fiber based sensing and actuating devices that have been successfully integrated into fluidic microchannels that are part of microfluidic and lab-on-chip systems. Fluidic microsystems possess the advantages of reduced sample volumes, faster and more sensitive biological assays, multi-sample and parallel analysis, and are seen as the de facto bioanalytical platform of the future. This paper considers the cases where the optical fiber is not merely used as a simple light guide delivering light across a microchannel, but where the fiber itself is engineered to create a new sensor or tool for use within the environment of the fluidic microchannel.

Single-mode fiber variable optical attenuator based on a ferrofluid shutter.

We report on the fabrication and characterization of a single-mode fiber variable optical attenuator (VOA) based on a ferrofluid shutter actuated by a magnetic field created by a low voltage electromagnet. We compare the performance of a VOA using oil-based ferrofluid, with one VOA using water-based 12 ferrofluid, and demonstrate broadband optical attenuation of up to 28 dB with polarization dependent 13 loss of 0.85 dB.

Dual Q-switched laser outputs from a single lasing medium using an intracavity MEMS micromirror array.

An intracavity array of individually controlled microelectromechanical system scanning micromirrors was used to actively Q-switch a single side-pumped Nd:YAG gain medium. Two equal power independent laser outputs were simultaneously obtained by separate actuation of two adjacent micromirrors with a combined average output power of 125 mW. Pulse durations of 28 ns FWHM at 8.

Absorption line profile recovery based on TDLS and MEMS micro-mirror for photoacoustic gas sensing.

A novel and efficient absorption line recovery technique is presented. A micro-electromechanical systems (MEMS) mirror driven by an electrothermal actuator is used to generate laser intensity modulation through the mirror reflection. Tunable diode laser spectroscopy (TDLS) and photoacoustic spectroscopy (PAS) are used to recover the target absorption line profile which is compared with the theoretical Voigt profile.

Control of solid-state lasers using an intra-cavity MEMS micromirror.

High reflectivity, electrothermal and electrostatic MEMS (Micro-Electro-Mechanical Systems) micromirrors were used as a control element within a Nd-doped laser cavity. Stable continuous-wave oscillation of a 3-mirror Nd:YLF laser at a maximum output power of 200 mW was limited by thermally-induced surface deformation of the micromirror. An electrostatic micromirror was used to induce Q-switching, resulting in pulse durations of 220 ns - 2 μs over a repetition frequency range of 6 kHz - 40 kHz.

Optical fiber-coupled ocular spectrometer for measurement of drug concentration in the anterior eye--applications in pharmaceuticals research.

This paper describes in detail a novel optoelectronic system designed to measure drug absorption in the anterior segment of the eye following topical application of drug formulations. This minimally invasive measurement technique offers both a method for determining drug concentration in human eyes, and demonstrates an alternative to current testing processes in model animals, which require paracentesis of the anterior chamber of the eye. The optoelectronic technique can be used with formulations, which possess appropriate spectral characteristics, namely unique absorption or fluorescence spectra.

Minimally invasive spectroscopic system for intraocular drug detection.

A novel, minimally invasive measurement technique has been developed for the detection of drugs in the anterior chamber of the eye. Presently there is no satisfactory, real-time detection method available to the ophthalmic community. Accurate determination of drug concentrations in the eye would be of great value and assistance to researchers and manufacturers of ophthalmic drugs and ocular implants, to enable a better understanding of intraocular pharmacokinetics.