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An x-ray induced electric current of an x-ray mirror (drain current) was measured as a function of the incident x-ray photon flux and the mirror angle at the Soft Matter Interfaces (SMI) beamline at NSLS-11. The mirror was a horizontal focusing bimorph mirror operated in vacuum. The electric current was found to be an approximately linear function of the incident photon flux. The drain current as a function of the mirror angle has a maximum in vicinity of the critical angle of total external reflection. Inreflection from the Si stripe of the mirror, an additional signal enhancement was found at the critical angle corresponding to the the 3rd radiation harmonic under high-power load conditions of the double-crystal Si 111 monocbrumator operated upstream of the mirror (at the primary photon energy of 2.15 keV). The drain current as a function of aogle of the monochromator’s second crystal (rocking curve) measured at the critical angle revealed a harmonic contamination due to higher order Bragg reflections. The observations validate the utility of the x-ray induced current for beamline alignment and diagnostics.

The X-ray pair distribution function beamline I15-1 at Diamond Light Source requires optical elements that focus a wiggler X-ray beam of high energy (40-80 keV) and large area (11.0 mm × 4.4 mm) into a small spot (FWHM∼700 µm (h) × 20 µm (v)) at a variable distance between sample and detector. X-ray lenses do not reach the necessary effective apertures because of absorption and the limits of fabrication technology. The aperture of conventional silicon X-ray mirrors, even with metal coatings, is likewise limited by the shallow critical angle for high-energy X-rays. As a solution, CINEL Strumenti Scientifici delivered the first multilayer-coated bimorph mirror for use at a synchrotron beamline. A silicon substrate was polished by Thales-SESO to have an elliptically curved surface. The mirror was then coated with three multilayer stripes (Ni/B4C, W/B4C, Pt/B4C) of unmatched 1 m length by Rigaku Innovative Technologies. Each stripe’s d-spacing was chosen so that the Bragg angle of its first-order reflection would occur at 4.2 mrad at the center of the mirror. Moreover, each stripe’s d-spacing was graded along the mirror’s length to ensure high reflectivity from the whole stripe. Piezoelectric actuators were then glued to the sides of the coated substrate by Thales-SESO to convert it to a bimorph deformable mirror. This enables the mirror to vary its focusing distance from 3.6 m to 4.8 m, and to compensate for residual long-wavelength slope errors. The mirror’s capability to provide vertical focusing exceeding specifications was demonstrated by ex-situ metrology and in-situ X-ray measurements. Representative results are presented.

In this study, a hybrid energy harvesting device is presented whichsimultaneously harvests energy from solar radiation and mechanical vibration using the photovoltaic, piezoelectric, and electromagnetic mechanisms. The device consists of a bimorph piezoelectric cantilever beam having Lead Zirconate Titanate (PZT) crystal patches on top and bottom surfaces of an Aluminum substrate. The tip of the cantilever beam has an attached permanent magnet which oscillates within stationary coils fixed to the top and bottom of a housing inside a casing. The exterior surface of the casing is covered by silicon photovoltaic panel that can capture energy from solar illumination. All the segments are interconnected by an electric circuit to generate a combined output when subjected to solar radiation and mechanical vibration. The hybrid prototype of the harvester is optimized by using finite element analysis to find the resonance frequencies and stress distributions. Results for power output are obtained at the resonance frequency of the hybrid beam using an optimum common load resistance. As the power outputs of all the mechanisms are combined, a high power output can be achieved by the proposed hybrid energy harvester.

The Piezoelectric energy harvester system has fascinated rigorous consideration in the area of self powered wireless sensor networks. A piezoelectric energy harvesting system constitutes three components namely, piezoelectric device, interfacing circuits and storage. This paper represents the study of geometrical and material variation on the resonant frequency and output power of bimorph piezoelectric energy harvester. It has been observed that large length of beam or small thickness of beam resulting in reduced resonant frequency. Further, it can also be reduced by increasing the length or height of proof mass or by using the high mass density material for proof mass Similarly, the output power of bimorph piezoelectric energy harvester can be increased by decreasing the length or increasing the width or thickness of the beam. Furthermore, the use of low mass density material for proof mass and low damping ratio are another solutions of increasing the output power of bimorph piezoelectric energy harvester.

BL-15A is a new x-ray undulator beamline at the Photon Factory. It will be dedicated to two independent research activities, simultaneous XAFS/XRF/XRD experiments, and SAXS/WAXS/GI-SAXS studies. In order to supply a choice of micro-focus, low-divergence and collimated beams, a double surface bimorph mirror was recently developed. To achieve further mirror surface optimization, the pencil beam scanning method was applied for “in-situ” beam inspection and the Inverse Matrix method was used for determination of optimal voltages on the piezoelectric actuators. The corrected beam profiles at every focal spot gave good agreement with the theoretical values and the resultant beam performance is promising for both techniques. Quick and stable switching between highly focused and intense collimated beams was established using this new mirror with the simple motorized stages.

This paper presents design, simulation results and envisaged fabrication process for a versatile MEMS bimorph actuator with large out of plane displacement and high resolution. A comparative study of mechanical, thermal and electrical response of the micro-actuator is presented by using two well-known MEMS simulation tools. The bimorph structure measuring 700 × 1280 mm2 is fully integrable with CMOS fabrication process. It is indented for tunable filter applications where the precise vertical motion of the payload, the top metallic electrode anchored rigidly to bimorph ‘springs’ spans the vertical range of 250-300 microns with submicron resolution. Each bimorph spring resembles a hair pin structure and is composed of materials with large difference in thermal expansion coefficients e.g. electroplated gold and polysilicon for optimal out-of-the plane deflection. The novel structure can also be configured for analog micro-mirror based optical and IR spectroscopy applications by controlling the actuation bias and top electrode surface parameters.

We present the final design of the x-ray optics and experimental stations of two macromolecular crystallography (MX) beamlines at the National Synchrotron Light Source-II. The microfocusing FMX beamline will deliver a flux of ∼5×1012 ph/s at 1 A into a 1 – 20 µm spot, its flux density surpassing current MX beamlines by up to two orders of magnitude. It covers an energy range from 5 – 30 keV. The highly automated AMX beamline is optimized for high throughput, with beam sizes from 4 – 100 µm, an energy range of 5 – 18 keV and a flux at 1 A of ∼1013 ph/s. A focus in designing the beamlines lay on achieving high beam stability, for example by implementing a horizontal bounce double crystal monochromator at FMX. A combination of compound refractive lenses and bimorph mirror optics at FMX supports rapid beam size changes. Central components of the in-house developed experimental stations are horizontal axis goniometers with a target sphere of confusion of 100 nm, piezo-slits for dynamic beam size changes during...

The article describes design and principle of control of small-size inspection robot with vibratory piezoelectric actuator and possibility of its application for non-destructive evaluation (NDE). Controlled movement of robot is implemented using single bimorph piezoelement by means of frequency control of electric voltage applied to piezoelement. Such scheme of control is realized as a result of application of structural asymmetry principle consisting in relative shift of resonant characteristics of robot supporting elements (legs) by means of imparting geometric asymmetry to them. During movement of robot upon inspected surface each of its legs excites in substrate elastic waves which can be registered by another robot as a consequence of piezoelectric effect reversibility. As a result group of communicating robots (robotic swarm) will be able to distribute over the surface of inspected object and perform its multiagent control. This will give possibility to accelerate and simplify inspection of large and geometrically-complex objects. Autonomy and compactness of the described robots will also make reasonable their application for NDE of hard-to-access surfaces and potentially hazardous objects.

Nonlinear vibrations of a bimorph LiNbO3 microcantilever are investigated. A periodically poled LiNbO3 wafer is used as an initial chip. The cantilever is micro‐machined near an interdomain wall between two inversely poled domains. The vibrations are excited by an applied rf‐voltage, and motion of a cantilever tip is detected optically. Nonlinearity is revealed by measuring the changes in the dependencies of vibration amplitude versus frequency when amplitude increases, and by reading of sub‐harmonic oscillations. A surface of the microcantilever may be modified with a silane, which is sensitive to certain biomolecules. This composite nonlinear micro‐vibrator may be used for developing a smart biosensor operating in ambient atmosphere in a real time mode.

Functionally Graded Materials (FGMs) possess continuously graded material properties and are characterized by spatially varying microstructures. The smooth variation of properties may offer advantages such as reduction of stress concentration and increased bonding strength. Recently, this concept has been explored in piezoelectric materials to improve properties and to increase the lifetime of bimorph piezoelectric actuators. Usually, elastic, piezoelectric, and dielectric properties are graded along the thickness of a piezoceramic FGM. Thus the gradation law of piezoceramic properties can influence the performance of piezoactuators. In this work, topology optimization has been applied to find the optimum gradation variation in piezoceramic FGMs to improve actuator performance measured in terms of output displacements. A bimorph type actuator design is considered. Accordingly, the optimization problem is posed as finding the optimized gradation variation of piezoelectric properties that maximizes output displacement or output force in the tip of bimorph actuator. The optimization algorithm combines the finite element method with sequential linear programming (SLP). The finite element method applied is based on the graded finite element concept where the properties change smoothly inside the element. This approach provides a continuum approximation of material distribution (CAMD), which is appropriate to model FGMs. The alternative FGM modelling using traditional FEM formulation and discretizing the FGM into layers gives a discontinuous stress distribution, which is not compatible with FGM behavior. The present results consider gradation between two different piezoceramic properties and consider two‐dimensional models with plane stress assumption.

An important feature of X‐ray Piezoelectric Bimorph Mirror (PBM) is the possibility to continuously vary its curvature (dynamical bending); this ability allows the precise adjustment of their optical properties to different beamline geometries and permits the variation of the grazing angle of incidence or to optimize the focal spot dimensions in the experimental chamber. When a driving voltage is applied at a particular position of the mirror, one of the piezo plates shrinks while the other one expands and, as an example, it can result in a purely spherical bending of the device if the same voltage is applied to all electrodes. The applied voltages have to be kept extremely stable on a very long time scale (weeks or even months). This means that the performance and the general behavior of the mirror are strongly dependent on the power supply used to drive it. For this challenging application, Sincrotrone Trieste developed a particularly stable high voltage bipolar power supply system (ranging from −2kV to + 2kV, zero crossing). This system is controlled by an Intel SBC board and accessible via Ethernet through any common web browser, Lab VIEW client or some of the most popular synchrotron facility control systems (Epics and Tango for instance). The maximum drain and source capabilities are 500uA per channel. Voltage monitoring is achieved by sensing the real output and feeding it to a true 16bit ADC. The voltage resolution achieved is about 60mV while the current resolution is about 60nA. Noise and residual ripple (rms) are better than 15ppm/FS and, most important, the long term stability (1 week observation) is better than 100ppm/FS. Some metrological measurements, on different bimorph mirrors, was carried out at the optical laboratory of Elettra. These measures demonstrate the high level of resolution and stability of the power supplies, able to change considerably the radius of curvature of the mirror and, in the meantime, correct even very small shape error.

A new macromolecular crystallographic facility developed by GM/CA‐CAT is operational at the Advanced Photon Source (APS). The facility consists of three beamlines: two lines based on the first “hard” dual canted undulators and one bending magnet beamline. The ID lines are operational, and the BM line is being commissioned. Both insertion device (ID) beamlines are independently tunable over a wide energy range. The inboard ID lines have been upgraded with a new insertion device to provide enhanced performance for MAD phasing experiments near the selenium and bromine K‐edges. The ID line monochromators’ crystals are indirectly, cryogenically cooled for improved performance and reliability. Focusing is achieved by long bimorph mirrors in a Kirkpatrick‐Baez geometry. This paper describes the design of the beam lines and the optical characterization of the mirrors and monochromators.

All scientific instruments in the field of astronomy and lasers are now using adaptive mirrors to improve the spot size quality. For X‐ray mirrors, which are used in grazing angle, the design of such mirrors has to be specific to take into account the rectangular shape of the mirror. We introduce the differences between traditional mechanical active optics and adaptive mirrors based on a bimorph structure with piezoelectric ceramics and give the detail of the last achievements.

X‐ray piezoelectric bimorph mirrors, pioneered at the ESRF in the 90’s and subsequently optimized at Spring‐8 in the 00’s, have nowadays reached full maturity. The most recently manufactured devices not only achieved state‐of‐the‐art optical results at the beamline but also gave a clear indication of the still untapped potential that these devices have to realize X‐ray adaptive optics. By using their unique capability to locally steer sub‐segments of the reflective surface (adaptive zonal control), a 300 mm long bimorph could be shaped to an arbitrary surface described by a 9th order polynomial with residual shape errors as small as 100 A rms over its full optically active length. Results recently obtained at the APS demonstrate the ability of bimorph mirrors to obtain sharp, very high‐contrast focused beams even when the incoming X‐ray wavefront is heavily distorted: a 8.5 (H) × 5.0 (V) μm2 FWHM doubly focused focal spot could be achieved at 33.6 keV. Previous data collected at Spring‐8 had already demonstrated the extreme sharpness of the focused beam when the incoming wavefront is an undistorted spherical wave. In both cases the bimorph mirrors were illuminated over their full optical length and a large focusing distance of 1 m could be used.

For improving the main parameters of photoacoustic microscope (PAM) authors made and investigated some types of piezosensors. The PAM with bending bimorph piezoelectric sensor from PZT-5A ceramics had the greatest sensitivity at the frequency of PAM 1 kHz.

Design equations, based on Ralph Woollett’s 1960 report [‘‘The Flexural Disk Transducer,’’ U.S. Navy Underwater Sound Laboratory Research Report No. 490], are presented for a bimorph accelerometer. Figures‐of‐merit are compared for PZT‐4, PZT‐5A, PZT‐5H, PZT‐8 piezoceramics, and PVDF‐TrFE copolymer. Neutrally buoyant, spherical and cylindrical accelerometer configurations can be designed to meet bandwidth, sensitivity, and depth requirements. Experimental results for PZT‐8 bimorphs indicate that simply‐supported edge conditions are easily achievable.