An optical, mirror system has been built using MEMS techniques while employing lead zirconate titanate (PZT) thin films as strong piezoelectric material. The system consists of two parallel silicon cantilever beams, on which the PZT was deposited, which were arranged to project inward from a common frame. The beams were laterally offset over a distance appropriate to fit a mirror between them. One end of each beam is fixed to the frame, while the other end is attached to a sideways projected bar, directed to the other beam. To each sideways bar a connector, parallel to the original beam, pointing toward the frame, was attached. Between both connectors a mirror was attached. The application of voltage across the electrodes on top and below the PZT causes the beams to bend as a monomorph, and the mirror between the beams to rotate around an axis through its center. A variety of thicknesses have been chosen to fabricate these devices. The mirror angle at a given voltage is inversely proportional to the square of the beam thickness, while the bandwidth is proportional to the thickness. Beams with thickness of 5 µm were used to achieve optical angles in static mode of up to 40° using voltages up to 13 V. In that case a bandwidth of around 700 Hz was observed. In resonance optical angles of 10° with a driving voltage as low as 100 mV were achieved. For devices with 30 µm thick beams, optical angles of up to 30° were observed in resonance at 17.4 kHz at driving voltages of around 6 V. Due to the proprietary design a figure of merit which may be defined as a product of the resonance frequency and optical angle, is much higher than one of the other PZT scanners.

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Here we propose a bio‐MEMS device designed to evaluate contractile force and conduction velocity of cell sheets in response to mechanical and electrical stimulation of the cell source as it grows to form a cellular sheet. Moreover, the design allows for the incorporation of patient‐specific data and cell sources. An optimized device would allow cell sheets to be cultured, characterized, and conditioned to be compatible with a specific patient's cardiac environment in vitro, before implantation. This design draws upon existing methods in the literature but makes an important advance by combining the mechanical and electrical stimulation into a single system for optimized cell sheet growth. The device has been designed to achieve cellular alignment, electrical stimulation, mechanical stimulation, conduction velocity readout, contraction force readout, and eventually cell sheet release. The platform is a set of comb electrical contacts consisting of three‐dimensional walls made of polydimethylsiloxane and coated with electrically conductive metals on the tops of the walls. Not only do the walls serve as a method for stimulating cells that are attached to the top, but their geometry is tailored such that they are flexible enough to be bent by the cells and used to measure force. The platform can be stretched via a linear actuator setup, allowing for simultaneous electrical and mechanical stimulation that can be derived from patient‐specific clinical data.

Ultra thin (<1 μm) polarizers with high polarizing efficiency based on lyotropic dichroic dyes have been developed for LCD and other applications. The developed polarizers reveal rod‐like chromophore structure (O‐polarizers), same as conventional iodine polarizers in contrast to the first‐generation polarizers with disc‐like chromophores structure (E‐polarizers). Polarizing efficiency, single transmission, dichroic ratio, and color of developed O‐polarizers are close to the iodine polarizers.