This PDF file contains the front matter associated with SPIE Proceedings Volume 9375 including the Title Page, Copyright information, Table of Contents, Introduction, and Conference Committee listing.

This paper presents a large aperture micro scanning mirror (MSM) array especially developed for the novel 3D-laser camera Fovea3D. This 3D-camera uses a pulsed ToF technique with 1MVoxel distance measuring rate and targets for a large measurement range of 30…100m and FOV of 120°x60° at video like frame rates. To guarantee a large reception aperture of ≥ 20mm, large FOV and 3200 Hz bi-directional scanning frequency at the same time, a hybrid assembled MSM array was developed consisting of 22 reception mirrors and a separate sending mirror. A hybrid assembly of frequency selected scanner elements and a driving in parametric resonance were chosen to enable a fully synchronized operation of all scanner elements. For position feedback piezo-resistive position sensors are integrated on each MEMS chip. The paper discusses details of the MEMS system integration including the synchronized operation of multiple scanning elements.

Many applications could benefit from miniaturized systems to scan blood vessels behind the retina in the human eye, so called „retina scanning“. This reaches from access control to sophisticated security applications and medical devices. High volume systems for consumer applications require low cost and a user friendly operation. For example this includes no need for removal of glasses and self-adjustment, in turn guidance of focus and point of attraction by simultaneous projection for the user. A new system has been designed based on the well-known resonantly driven 2-d scanner mirror of Fraunhofer IPMS. A combined NIR and VIS laser system illuminates the eye through an eye piece designed for an operating distance allowing the use of glasses and granting sufficient field of view. This usability feature was considered to be more important than highest miniaturization. The modulated VIS laser facilitates the projection of an image directly onto the retina. The backscattered light from the continuous NIR laser contains the information of the blood vessels and is detected by a highly sensitive photo diode. A demonstrational setup has been realized including readout and driving electronics. The laser power was adjusted to an eye-secure level. Additional security features were integrated. Test measurements revealed promising results. In a first demonstration application the detection of biometric pattern of the blood vessels was evaluated for issues authentication in.

We present an innovative rotational MEMS mirror that can control the direction of propagation of light beams inside of planar waveguides implemented in silicon photonics. Potential applications include but are not limited to optical telecommunications, medical imaging, scan and spectrometry. The mirror has a half-cylinder shape with a radius of 300 μm that provides low and constant optical losses over the full angular displacement range. A circular comb drive structure is anchored such that it allows free or latched rotation experimentally demonstrated over 8.5° (X-Y planar rotational movement) using 290V electrostatic actuation. The entire MEMS structure was implemented using the MEMSCAP SOIMUMPs process. The center of the anchor beam is designed to be the approximate rotation point of the circular comb drive to counter the rotation offset of the mirror displacement. A mechanical characterization of the MEMS mirror is presented. The latching mechanism provides up to 20 different angular locking positions allowing the mirror to counter any resonance or vibration effects and it is actuated with an electrostatic linear comb drive. An innovative gap closing structure was designed to reduce optical propagation losses due to beam divergence in the interstitial space between the mirror and the planar waveguide. The gap closing structure is also electrostatically actuated and includes two side stoppers to prevent stiction.

A higher achievable scan speed and the capability to integrate two scan axes in a very compact device are fundamental advantages of MEMS scanning mirrors over conventional galvanometric scanners. There is a growing demand for biaxial high speed scanning systems complementing the rapid progress of high power lasers for enabling the development of new high throughput manufacturing processes. This paper presents concept, design, fabrication and test of biaxial large aperture MEMS scanning mirrors (LAMM) with aperture sizes up to 20 mm for use in high-power laser applications. To keep static and dynamic deformation of the mirror acceptably low all MEMS mirrors exhibit full substrate thickness of 725 μm. The LAMM-scanners are being vacuum packaged on wafer-level based on a stack of 4 wafers. Scanners with aperture sizes up to 12 mm are designed as a 4-DOF-oscillator with amplitude magnification applying electrostatic actuation for driving a motor-frame. As an example a 7-mm-scanner is presented that achieves an optical scan angle of 32 degrees at 3.2 kHz. LAMM-scanners with apertures sizes of 20 mm are designed as passive high-Q-resonators to be externally excited by low-cost electromagnetic or piezoelectric drives. Multi-layer dielectric coatings with a reflectivity higher than 99.9 % have enabled to apply cw-laser power loads of more than 600 W without damaging the MEMS mirror. Finally, a new excitation concept for resonant scanners is presented providing advantageous shaping of intensity profiles of projected laser patterns without modulating the laser. This is of interest in lighting applications such as automotive laser headlights.

A high brightness Head-Up Display (HUD) module was demonstrated with a fast, dual-axis MEMS mirror that displays vector images and text, utilizing its ~8kHz bandwidth on both axes. Two methodologies were evaluated: in one, the mirror steers a laser at wide angles of <48° on transparent multi-color fluorescent emissive film and displays content directly on the windshield, and in the other the mirror displays content on reflective multi-color emissive phosphor plates reflected off the windshield to create a virtual image for the driver. The display module is compact, consisting of a single laser diode, off-the-shelf lenses and a MEMS mirror in combination with a MEMS controller to enable precise movement of the mirror’s X- and Y-axis. The MEMS controller offers both USB and wireless streaming capability and we utilize a library of functions on a host computer for creating content and controlling the mirror. Integration with smart phone applications is demonstrated, utilizing the mobile device both for content generation based on various messages or data, and for content streaming to the MEMS controller via Bluetooth interface. The display unit is highly resistant to vibrations and shock, and requires only ~1.5W to operate, even with content readable in sunlit outdoor conditions. The low power requirement is in part due to a vector graphics approach, allowing the efficient use of laser power, and also due to the use of a single, relatively high efficiency laser and simple optics.

PZT driven resonant micromirrors offer advantages of large scan angles and decreasing power consumption due to the benefits of resonant driving and high torque delivered by PZT actuators. Therefore they are entering into different application fields recently, for example as laser projection or head-up displays. For many uses position sensing of the micromirrors is necessary to set up closed loop controls. Thus, the development of integrated position sensors is aimed in this work. Investigation and evaluation of different position sensing principles have been performed. In previous works 1D and 2D PZT driven resonant micromirrors have been presented, which feature various spring suspensions and thinfilm PZT actuators as drivers. Due to the considerably different motion modes and resonant frequencies, which vary from 100 Hz up to 64 kHz, various position detection methods have been investigated. This work presents primarily fabrication and characterization results of the position sensors based on the direct piezoelectric effect, which will be compared to the position sensors using metallic strain gauge realized by the same fabrication technology. Analyses of the sensitivity, linearity and dynamic behavior of the sensors have been performed, by means of comparing the sensor signals and the micromirror position signals measured by a Position-Sensitive-Device. Advantages and drawbacks of the sensors are discussed and methods for eliminating the drawbacks are proposed.

An integrated position sensor for a dual-axis electromagnetic tilting mirror is presented. This tilting mirror is composed of a silicon based mirror directly assembled on a silicon membrane supported by flexible beams. The position sensors are constituted by 4 Wheatstone bridges of piezoresistors which are fabricated by doping locally the flexible beams. A permanent magnet is attached to the membrane and the scanner is mounted above planar coils deposited on a ceramic substrate to achieve electromagnetic actuation. The performances of the piezoresistive sensors are evaluated by measuring the output signal of the piezoresistors as a function of the tilt of the mirror and the temperature. White light interferometry was performed for all measurement to measure the exact tilt angle. The minimum detectable angle with such sensors was 30µrad (around 13bits) in the range of the minimum resolution of the interferometer. The tilt reproducibility was 0.0186%, obtained by measuring the tilt after repeated actuations with a coil current of 50mA during 30 min and the stability over time was 0.05% in 1h without actuation. The maximum measured tilt angle was 6° (mechanical) limited by nonlinearity of the MEMS system.

Diffractive micromirror arrays (MMA) are a special class of optical MEMS, serving as spatial light modulators (SLM) that control the phase of reflected light. Since the surface profile is the determining factor for an accurate phase modulation, high-precision topographic characterization techniques are essential to reach highest optical performance. While optical profiling techniques such as white-light interferometry are still considered to be most suitable to this task, the practical limits of interferometric techniques start to become apparent with the current state of optical MEMS technology. Light scatter from structured surfaces carries information about their topography, making scatter techniques a promising alternative. Therefore, a spatially resolved scatter measurement technique, which takes advantage of the MMA’s diffractive principle, has been implemented experimentally. Spectral measurements show very high contrast ratios (up to 10 000 in selected samples), which are consistent with calculations from micromirror roughness parameters obtained by white-light interferometry, and demonstrate a high sensitivity to changes in the surface topography. The technique thus seems promising for the fast and highly sensitive characterization of diffractive MMAs.

We are developing an adaptive optics system for earth observing remote sensing sensor. In this system, high spatial resolution and high signal to noise ratio has to be realized by a lightweight sensor system due to the launcher’s requirements. Moreover, simple hardware architecture has to be used to achieve high reliability, low cost, and short development period. Image based AOS realize these requirements without wavefront sensor. In remote sensing, it is difficult to use a reference point source unless the satellite controls its attitude toward a star. We propose the multi-mode phase diversity method using deformable mirror.

Near Infrared (NIR) spectrometers are widely used in many fields to measure material content, such as moisture, fat and protein in grains, foodstuffs and pharmaceutical powders. These fields include applications where only highly miniaturized and robust NIR sensors can be used due to small usable space, weight requirements and/or hostile working environment. Handheld devices for material inspection, online process automation and automotive industry introduce requirements for size, robustness and cost, which is currently difficult to meet. In this paper we present an advanced spectral sensor based on a tunable Microelectromechanical (MEMS) Fabry-Perot Interferometer. The sensor is fibercoupled, weighs 125 grams and fits to an envelope of 25x55x55 mm³. Three types of sensors cover the wavelength ranges from 1.35-1.7 μm, 1.55-2.0 μm and 1.7-2.2 μm, utilizing only a single pixel extended InGaAs detector, avoiding the expensive linear array detectors. We describe the design, principle of operation and calibration methods together with the control schemes. Some environmental tests are described and their results and finally application measurement results are presented along with discussion and conclusions.

Focal planes of 80x60 VO_x microbolometers with pixel pitch of 104 μm were developed in support of the remote sensing of ice clouds in the spectral range from 7.9 to 50 μm. A new design that relies on the use of central posts to support the microbolometer platform was shown effective in minimizing the structural deformation usually occurred in platforms of large area. A process for goldblack coating and patterning of the focal plane arrays was established. It was found that the goldblack absorbs more than 98 % and 92 % of incident light respectively at wavelengths shorter and longer than 20 μm. Moreover, a spectral uniformity of better than 96 % was achieved in all spectral channels required for the measurements. The noise figures derived from the data acquired over short periods of acquisition time showed the evidence of a correlation with the format of the addressed sub-arrays. This correlation was not observed in the data acquired over long periods of time, suggesting the presence of low frequency effects. Regardless of the length of acquisition time, an improvement of noise level could be confirmed when the operating temperature was increased. The dependence of responsivity on sub-array format and operating temperature was investigated. The noise equivalent power derived from this study was found to be in the range from 45 to 80 pW, showing that the far infrared focal plane arrays are suited for use in the intended application.

A highly compact and low power consuming Q-switch module was developed based on a fast single-axis MEMS mirror, for use in eye-safe battery-powered laser range finders The module’s 1.6mm x 1.6mm mirror has <99% reflectance at 1535nm wavelength and can achieve mechanical angle slew rates of over 500 rad/sec when switching the Er/Yb:Glass lasing cavity from pumping to lasing state. The design targeted higher efficiency, smaller size, and lower cost than the traditional Electro-Optical Q-Switch. Because pulse-on-demand capability is required, resonant mirrors cannot be used to achieve the needed performance. Instead, a fast point-to-point analog single-axis tilt actuator was designed with a custom-coated high reflectance (HR) mirror to withstand the high intra-cavity laser fluence levels. The mirror is bonded on top of the MEMS actuator in final assembly. A compact MEMS controller was further implemented with the capability of autonomous on-demand operation based on user-provided digital trigger. The controller is designed to receive an external 3V power supply and a digital trigger and it consumes ~90mW during the short switching cycle and ~10mW in standby mode. Module prototypes were tested in a laser cavity and demonstrated high quality laser pulses with duration of ~20ns and energy of over 3mJ.

In this paper, mechanical resonant frequencies of a nanoelectromechanical systems (NEMS) device are tuned by light, in which optical spring effect plays a role. A NEMS spring mechanism with multi-degree of freedom (DOF) is adopted here. Double-coupled nanobeam photonic crystal cavities (PCCs) are utilized to pump the optical spring effect. One of the PCCs is fixed, while the other is driven by the NEMS mechanism. We investigate the shift of the mechanism’s firstorder in-plane translational (I1) resonance mode tuned by the incident laser wavelengths across the fourth-order even (TE_e,4) and odd (TE_o,4) modes of the coupled cavities. It shows a nonlinear relationship between the I1 mechanical frequency and the laser wavelength. We also investigate the frequency of the third-order torsional (T3) mode versus the wavelengths across the same cavity TE_e,4 mode and it shows a weaker torsional optical spring effect.

VTT’s optical MEMS Fabry-Perot interferometers (FPIs) are tunable optical filters, which enable miniaturization of spectral imagers into small, mass producible hand-held sensors with versatile optical measurement capabilities. FPI technology has also created a basis for various hyperspectral imaging instruments, ranging from nanosatellites, environmental sensing and precision agriculture with UAVs to instruments for skin cancer detection. Until now, these application demonstrations have been mostly realized with piezo-actuated FPIs fabricated by non-monolithical assembly method, suitable for achieving very large optical apertures and with capacity to small-to-medium volumes; however large-volume production of MEMS manufacturing supports the potential for emerging spectral imaging applications also in large-volume applications, such as in consumer/mobile products. Previously reported optical apertures of MEMS FPIs in the visible range have been up to 2 mm in size; this paper presents the design, successful fabrication and characterization of MEMS FPIs for central wavelengths of λ = 500 nm and λ = 650 nm with optical apertures up to 4 mm in diameter. The mirror membranes of the FPI structures consist of ALD (atomic layer deposited) TiO₂-Al₂O₃ λ/4- thin film Bragg reflectors, with the air gap formed by sacrificial polymer etching in O2 plasma. The entire fabrication process is conducted below 150 °C, which makes it possible to monolithically integrate the filter structures on other ICdevices such as detectors. The realized MEMS devices are aimed for nanosatellite space application as breadboard hyperspectral imager demonstrators.

Focal plane array (FPA) technology is mature and is widely used for imaging applications. However, FPAs have broadband responses which limit their ability to provide high performance in hyperspectral applications such as detection of buried explosives, and identifying the presence of explosive chemicals and their concentrations. EPIR is currently developing Micro-Opto-Electro-Mechanical System (MOEMS) Fabry-Perot interferometer filter (FPF) devices for FPAs. In this paper, we present our approach to MOEMS FPF design and fabrication that will meet the size requirements for large format FPA hyperspectral imaging. We also report the performance of our FPF resonance cavity, capable of up to 3 μm change gap in tens of nanometer increments.

We describe a technological platform developed for miniaturization of optical imaging instruments, such as laser scanning confocal microscopes or Optical Coherence Tomography devices. The platform employs multi-wafer vertical integration approach, combined with integrated glass-based micro-optics and heterogeneous bonding and interconnecting technologies. In this paper we focus on the unconventional fabrication methods of monolithic micro-optical structures and components in borosilicate glass (e.g. micro beamsplitters, refractive microlenses) for optical beam shaping and routing. In addition, we present hybrid laser-assisted integration of glass ball microlenses on the silicon MEMS actuators for transmissive beam scanning as well as methods of electrical signals distribution through thick glass substrates, based on HF etched via holes.

We report a newly developed two-dimensional MEMS optical scanner based on the ADRIP (Arc Discharge Reactive Ion-Plating) deposited piezoelectric PZT film of typical 4 μm. A circular mirror of 1.2 mm in diameter is suspended within a pair of resonant mechanism that oscillates at 25 kHz for ±12° mechanical angle with a typical voltage of 10 V. A gimbal plate including the mirror is supported with another pair of meandering suspensions to tilt the plate in the orthogonal direction at 60 Hz for the off-resonant vertical motion of ±8° mechanical. Overall power consumption of the piezoelectric actuation was 100 mW or less. As a mechanical reinforce, a rib-structure was designed on the backside of the mirror by using a structural optimization tool TOSCA to suppress the dynamic curvature to 100 nm or less. A piezoelectric sensor was also integrated in the identical PZT film after optimizing the electrode shape to pick up the mechanical angle of the scanner and to give a trigger signal to the control system. A plug-in type pico-projector optics and electronics has been assembled in a 7.5 cm × 12 cm × 5 cm volume with RGB lasers to demonstrate a HD (high definition) class image projection of 720 horizontal lines. The fundamental resonance of the entire scanner mechanism was made to be 1 kHz or higher, thereby exhibiting a compatibility with vehicle applications.

Nanoimprinting techniques are an attractive solution for next generation lithography methods for several areas including photonic devices. A variety of potential applications have been demonstrated using nanoimprint lithography (NIL) (e.g. SAW devices, vias and contact layers with dual damascene imprinting process, Bragg structures, patterned media) [1,2]. Nanoimprint lithography is considered for bridging the gap from R and D to high volume manufacturing. In addition, it is capable to adapt to the needs of the fragmented and less standardized photonic market easily. In this work UV-NIL has been selected for the fabrication process of 3D-photonic crystals. It has been shown that UVNIL using a multiple layer approach is well suited to fabricate a 3D woodpile photonic crystal. The necessary alignment accuracies below 100nm were achieved using a simple optical method. In order to obtain sufficient alignment of the stacks to each other, a two stage alignment process is performed: at first proximity alignment is done followed by the Moire´ alignment in soft contact with the substrate. Multiple steps of imprinting, etching, Si deposition and chemical mechanical polishing were implemented to create high quality 3D photonic crystals with up to 5 layers. This work has proven the applicability of nanoimprint lithography in a CMOS compatible process on 3D photonic crystals with alignment accuracy down to 100nm. Optimizing the processes will allow scaling up these structures on full wafers while still meeting the requirements of the designated devices.

The design and manufacturing of a piezoelectrically driven translatory MEMS actuator is presented, which features a 7 mm aperture and four thin-film PZT actuators achieving large displacements. The actuator performs piston mode oscillation in resonance which can serve for Fourier Transform Infrared Spectroscopy (FTIR). Thereby vertical displacements in piston mode of up to ± 800 μm at 163 Hz and 25 V driving sinusoidal voltage has been achieved under ambient conditions. Due to the low frequencies and the low driving voltages only low power consumption is required. The effect of residual gas friction and internal friction on the piezo-driven MEMS actuator is analyzed by measuring Qvalues associated with the piston mode. Laser Doppler Vibrometry (LDV) was also used to detect and analyses the parasitic effects especially tilting which superimposes the vertical movement of the mirror. The deviation from the pure vertical piston mode was found to 1.3 μm along the x and 3 μm in the y-axis.

The paper presents the multi-wafer bonding technology as well as the integration of electrical connection to the zscanner wafer of the micromachined array-type Mirau interferometer. A Mirau interferometer, which is a key-component of optical coherence tomography (OCT) microsystem, consists of a microlens doublet, a MOEMS Z-scanner, a focusadjustment spacer and a beam splitter plate. For the integration of this MOEMS device heterogeneous bonding of Si, glass and SOI wafers is necessary. Previously, most of the existing methods for multilayer wafer bonding require annealing at high temperature, i.e., 1100°C. To be compatible with MEMS devices, bonding of different material stacks at temperatures lower than 400°C has also been investigated. However, if more components are involved, it becomes less effective due to the alignment accuracy or degradation of surface quality of the not-bonded side after each bonding operation. The proposed technology focuses on 3D integration of heterogeneous building blocks, where the assembly process is compatible with the materials of each wafer stack and with position accuracy which fits optical requirement. A demonstrator with up to 5 wafers bonded lower than 400°C is presented and bond interfaces are evaluated. To avoid the complexity of through wafer vias, a design which creates electrical connections along vertical direction by mounting a wafer stack on a flip chip PCB is proposed. The approach, which adopts vertically-stacked wafers along with electrical connection functionality, provides not only a space-effective integration of MOEMS device but also a design where the Mirau stack can be further integrated with other components of the OCT microsystem easily.

We present the design and fabrication of a tunable optical buffer device based on III-V semiconductor platform for telecommunication applications. The device comprises two indium phosphide suspended parallel waveguides with cross sectional dimension of 200 nm by 300 nm, separated by an air gap. The gap between the waveguides was designed to be adjustable by electrostatic force. Our simulation estimated that only 3 V is required to increase the separation distance from 50 nm to 500 nm; this translates to a change in the propagation delay by a factor of 2. The first generation of the suspended waveguide structure for optical buffering was fabricated. The sample was grown on an InP substrate by molecular beam epitaxy. The waveguide pattern is written onto a 300 nm thick InP device layer by electron beam lithography and plasma etching. Electrodes were incorporated into the structure to apply voltages for MEMS actuation.

Many applications of MOEMS microscanners rely on accurate position feedback. For MOEMS devices which do not have intrinsic on-chip feedback, position information can be provided with optical methods, most simply by using a reflection from the backside of a MOEMS scanner. By measuring the intensity distribution of the reflected beam across a quadrant diode, one can precisely detect the mirror’s deflection angles. Previously, we have presented a position sensing device, applicable to arbitrary trajectories, which is based on the measurement of the position of the reflected laser beam with a quadrant diode. In this work, we present a novel setup, which comprises the optical position feedback functionality integrated into the device package itself. The new device’s System-in-Package (SiP) design is based on a flip-folded 2.5D PCB layout and fully assembled as small as 9.2×7×4 mm³ in total. The device consists of four layers, which supply the MOEMS mirror, a spacer to provide the required optical path length, the quadrant photo-diode and a laser diode to serve as the light source. In addition to describing the mechanical setup of the novel device, we will present first experimental results and optical simulation studies. Accurate position feedback is the basis for closed-loop control of the MOEMS devices, which is crucial for some applications as image projection for example. Position feedback and the possibility of closed-loop control will significantly improve the performance of these devices.

This communication presents the results obtained for decreasing the response time of electrowetting-based real time focus correctors (liquid lenses). In order to provide a compact iris biometric system demonstrator, we have achieved a response time at 90% of 7.5 ms for a change in focalization from 0 diopter to 10 diopter with a liquid lens having an aperture of 1.9 mm. We have used a hydrodynamic fluid reorganization model to predict the features of these fast liquid lenses and evaluated the sensivity of the response time to the different conception parameters.

This work reports a simple, miniaturized optical sensing module for liquid refractometry. It is based on a stable Fabry- Perot resonator consisting of two silicon cylindrical mirrors with a cylindrical lens in the core. The lens is formed by a capillary tube through which the analyte to be analyzed passes. This setup enables volume refractometry, where light propagates through the sample realizing high interaction depth. The cylindrical surfaces achieve light confinement, reducing the light escaping loss encountered in classical cavities with straight mirrors; and hence high quality factor (Q) over 1,000 is attained. Exploiting this high Q, we adopt uncommon refraction index (RI) measurement criterion: we operate at a fixed wavelength and detect the power drop caused as a consequence to the spectral shift with RI change. Performing experimental testing using a tunable laser and a power-meter, the normalized spectra for different mixture ratios of acetone and deionized water are obtained. The wavelength corresponding to the maximal power transmission from pure acetone is taken as a reference. A vertical line at this wavelength cuts the successive transmission curves and enables measuring the power drop in the linear region, and from it the refractive index change Δn above the refractive index of the reference solution can be determined for 0.0023<Δn<0.0045. Sensitivity up to 4,094 dBm/RIU is achieved. A wider range is still accessible by the conventional method of tracing the shift in peak wavelengths: a range of Δn=0.0163 RIU can be scanned, with a sensitivity of 221 nm/RIU. Error analysis has been accomplished, and the design parameters of the device are discussed to evaluate the performance.

Notch filters based on fiber-coupled Fabry-Pérot cavity are formed by a reflector placed in close proximity to a dielectric-coated end of an optical fiber. This kind of optical filters is easy to tailor for a given application because the external mirror has less mechanical and optical constraints. In this paper we present a fiber-coupled Fabry-Pérot filter based on dielectric-coated optical fiber inserted into a fiber groove facing a metallized micromirror, where the latter is driven by a high-speed MEMS actuator. The microsystem is fabricated using Deep Reactive Ion Etching (DRIE) technology on SOI wafer. The optical axis is in-plane and the components are self-aligned. The DRIE etching depth is 150 μm; chosen for improving the out-of-plane stiffness of the actuator and increasing the micromirror optical throughput. The MEMS actuator type is closing-gap while its quality factor is improved by slotting the fixed plate. The actuator, therefore, achieves a travel distance larger than 800 nm and has a resonance frequency of 90 kHz. The notch filter exhibits a free spectral range up to 100 nm and a notch rejection ratio of 20 dB around a wavelength of 1300 nm. The presented device provides low cost wafer level production of the filter.

Fiber lasers are gaining wide attention nowadays due to their high stability, high reliability, low cost and compactness. Frequency modulation of the laser system has many applications such as wavelength tuning, active mode locking, generation of optical frequency combs and fiber sensors in general. In this work, we report frequency modulation of fiber ring laser system using transmission-type corner cube in-plane MEMS phase modulator fabricated by DRIE technology on an SOI substrate. The fiber-coupled MEMS-based phase modulator is inserted in a multilongitudinal mode fiber ring laser, which has a free spectral range of 345 kHz. By varying the applied voltage on the MEMS device, a wide range of the frequency modulation index can be achieved.

Experimental results of a large scanning grating with a diameter of 5mm and 1 kHz scan frequency are discussed. An optical diffraction grating is fabricated on a mirror single crystal silicon plate to scan the first diffraction order in the MIR-wavelength range over a quantum cascade laser facet. Special emphasis is on the development of the grating technology module to integrate it with high accuracy and reproducibility into the IPMS AME75 process flow. The principle EC-QCL setup with the scanning grating is described and first measurement results concerning laser output power and tuning range are presented.

A resonant micro optic gyro (RMOG) is a promising candidate for applications requiring small, light and robust gyros. A high-performance RMOG requires a low-loss micro-ring resonator, and thus a resonator having a high finesse. We experimentally create a new record for high-finesse micro-ring resonators by using 30-cm long low-loss fiber coils laid into the V-groove on a silicon substrate. Both the simulation and experimental results indicate that the 30-cm long micro-ring resonator is sufficient to build a tactical-grade RMOG. Experimentally, a bias stability of 0.046/s in 1800 s with an integration time of 1 s is successfully demonstrated.

There are numerous applications for micromirror arrays seen in our everyday lives. From flat screen televisions and computer monitors, found in nearly every home and office, to advanced military weapon systems and space vehicles, each application bringing with it a unique set of requirements. The microelectromechanical systems (MEMS) industry has researched many ways micromirror actuation can be accomplished and the different constraints on performance each design brings with it. This paper investigates a new “zipper” approach to electrostatically driven micromirrors with the intent of improving duel plane beam steering by coupling large deflection angles, over 30°, and a fast switching speed. To accomplish this, an extreme initial deflection is needed which can be reached using high stress bimorph beams. Currently this requires long beams and high voltage for the electrostatic pull in or slower electrothermal switching. The idea for this “zipper” approach is to stack multiple beams of a much shorter length and allow for the deflection of each beam to be added together in order to reach the required initial deflection height. This design requires much less pull-in voltage because the pull-in of one short beam will in turn reduce the height of the all subsequent beams, making it much easier to actuate. Using modeling and simulation software to characterize operations characteristics, different bimorph cantilever beam configurations are explored in order to optimize the design. These simulations show that this new “zipper” approach increases initial deflection as additional beams are added to the assembly without increasing the actuation voltage.

For enhance the grade ability of spherical robot, a new kind of spherical robot with climb link mechanism is designed. This kind of spherical robot can move in traditional way by the pendulum or move across large gradient slope by the new climb link mechanism. The mechanics model of the new spherical robot across slope by the climb link mechanism is created. Then the model is simulated by simulation software. The simulation result verifies the mechanism model’s accuracy. Then the mechanical model of this new spherical robot named BYQ-X was made out. The mechanical structure and motion control system are detailed introduced. Finally, the accuracy of the mechanical model, the validity of the climb link mechanism are verified by tests of mechanical model.

Piezomachined ultrasonic transducer (PMUT) arrays are commonly found in applications in the field of ultrasonography and gesture recognition systems. Their application for bio and chemical sample preparation is another possibility, based on their beam steering and acoustic field manipulation capabilities. Post-fabrication non-destructive measurement of key device temporal and spatial parameters is required in order to adjust either simulation models or tune fabrication steps. In this work we report an optical testing setup for measuring the acoustic spectrum of PMUT devices and arrays, characterize maximum deflection of PMUTs and piezopumps and investigate the load effect of electrical contacts on the spatial and temporal oscillation behavior of these piezoelectric structures. Spatial parameters are evaluated with digital holography and temporal parameters with single point Doppler shift and frequency-shifted. We employ this testing setup to measure our own designed PMUT structures which were fabricated at IME-Singapore, evaluating the relative merits of the PMUT design parameters.