This paper successfully demonstrates that a sensing device, with a microfluidic channel, integrated with interdigitated microelectrode (IDμE), is able to detect different glucose concentrations without immobilizing enzymes onto the surface of microelectrodes. Phosphate buffered saline (PBS) solution (10X) was used as a sensing medium and the measurement frequency determines the device sensitivity. Higher measurement frequency enhances sensitivity. A model of an equivalent circuit is proposed and a theoretical simulation and calculation are fitted with the experimental data. The principle of measurement is based on changes in the dielectric constant of the analyte dissolved in the buffer solution at different concentrations. Thus, an increased sensitivity is obtained at a higher measurement frequency (4 MHz). The sensing device demonstrated here has potential for application to disposable polymer lab-on-a-chips for biochemical analysis and clinical diagnostics.

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The effects of microlens aperture size on 3D imaging quality for a 5 x 5 microlens array in a light field camera are studied by Fourier optics in consideration of pupil sizes and the locations of main lens and each lens in a microlens array. The larger size of the lenses in the microlens array provides higher sub-aperture image resolution. The techniques demonstrated in this paper can be useful to evaluate sub-aperture image performance in a light field camera without requiring large computations

The supplementary zones surrounding an ordinary Fresnel zone plate (FZP) are utilized to improve the optical resolution at focus. Based on the Fresnel-Kirchhoff diffraction formula, an optimization model is used to design the supplementary zones-surrounded FZP (SZFZP). We justified this optimization model by comparing the numerical simulations and experimental measurements in the visible light region. As expected, the comparison shows a good fit between the simulation and measurement. Mostly, both results showed that the optical resolution and the focal intensity in the visible light region are improved by applying the optimized SZFZP. Afterwards, this model is used to design the SZFZP for applications in extreme ultraviolet (EUV) light. At this point, we demonstrated the ability to fabricate the optimized SZFZP in the EUV region. In addition, we simulated the focusing properties for the designed SZFZP. Consequently, the numerical results for EUV light focused by the designed SZFZP exhibited better performances in optical resolution and intensity.

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