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In this paper, for the first time, excimer laser micromachining is applied to create new electrooptical devices called substrate integrated modulators, consisting of new optical and microwave waveguides on LiNbO 3 substrates. The fact of having both optical and microwave waveguides, offers the possibilities to modulate high-frequency optical signal (wavelength of 1.55 μm) by either millimeter or microwave signal (frequency of 60 GHz). Because LiNbO 3 is transparent between 370 nm to 5000 nm, 248 nm KrF excimer laser is one of the best candidates for performing fine micromachining of this material. Cutting the LiNbO 3 wafer, making holes, creating a ridge optical waveguide and fabricating a specific pattern of holes for microwave applications by 248 nm excimer laser are presented in this paper.

In most parts of the retina, neuronal circuits process visual signals represented by slowly changing membrane potentials, or so-called graded potentials. A feasible approach to speculate about the functional roles of retinal neuronal circuits is to reproduce the graded potentials of retinal neurons in response to natural scenes. In this study, we developed a simulation platform for reproducing graded potentials with the following features: real-time reproduction of retinal neural activities in response to natural scenes, a configurable model structure, and compact hardware. The spatio-temporal properties of neurons were emulated efficiently by a mixed analog-digital architecture that consisted of analog resistive networks and a field-programmable gate array. The neural activities on sustained and transient pathways were emulated from 128 × 128 inputs at 200 frames per second.

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