For in-vivo imaging applications the use of conventional confocal microscope systems are simply not practical due to
their relatively large size and weight. There is, however, great interest from both the life science research community and
the clinical profession for the development of compact and portable micro-optical instrumentation capable of achieving
minimally invasive, in-vivo imaging of tissue with sub-cellular resolution. In this paper we describe a novel confocal
micro-imaging system incorporating, at its core, a thermally driven, non-resonant two-axis MEMS scanner which serves
as a substitute for the two single-axis galvanometer scanners commonly used in standard confocal imaging systems. In
this paper we describe the non-linearity of such devices and a number of techniques to compensate for this.
Design, experimental evaluation and performance of a tunable optical filter based on hybrid MOEMS is presented. The device meets the demodulation requirements for Fiber Bragg Gratings sensors reaching a repeatable tuning range over 400 pm.
In this paper we report a simple design of a micro-optical shutter/attenuator. The standard MUMPS process was used to fabricate the device. A vertically erected, gold-coated, 200x300 ?m side length micro-mirror was precisely placed between the end faces of two closely spaced optical fibers. The position of the micro-mirror with respect to the optical fiber end face was controlled by a nano-stepping motor array. Optical and mechanical tests were performed on the device. A 1.55 ?m laser beam was sent along the optical fiber. When the micro-mirror was removed from the front of the fiber, the coupling efficiency between two fibers was –10 dBm. Once the micro-mirror was placed in the optical path the coupling efficiency dropped to –51.5 dBm. The best attenuation was obtained when the micro-mirror blocked the whole cross-section of the laser beam diameter. It is evident that the device can operate as a high precision fiber optic attenuator or shutter.
The scratch drive actuator (SDA) is a key element in microelectromechanical System (MEMS) technology. The actuator can be designed to travel very long distance with precise step size. Various articles describe the characteristics of scratch drive actuators.3, 6, 8 The MEMS designer needs models of SDA in order to incorporate them into their Microsystems applications. The objective of our effort is to develop models for SDA when it is in the working state. In this paper, a suspended SDA plate actuated by electrostatic force is analyzed. A mathematical model is established based on electrostatic coupled mechanical theory. Two phases have been calculated because the plate will contact the bottom surface due to the electrostatic force. One phase is named non-contact mode, and another is named contact mode. From these two models, the relationship between applied voltage and contact distance has been obtained. The geometrical model of bending plate is established to determine the relationship between contact distance and step size. Therefore we can use those two results to obtain the result of step size versus applied voltage that we expect. Finally, couple-field electro-mechanical simulation has been done by commercial software IntelliSuite. We assume that the dimension of SDA plate and bushing are fixed. All the material properties are from JDSU Cronos MUMPs. A Veeco NT1000 surface profiling tool has been used to investigate the bending of SDA plate. The results of experimental and theoretical are compared.
We present models of two types of microsprings namely box- spring and zig-zag spring that can be used to measure the force generated by microactuators. The spring constant for both springs is calculated by FEM using ANSYS software. In these models, the effects of short beams that act as connectors in the spring structures are considered and analyzed by changing their width. Also, from the results, we find that the box spring appears more balanced than the zig- zag spring when the force is applied in the single central direction. A series of SDAs with b ox spring have been fabricated and forces of those SDAs have been calculated.
Microactuators are one of the key components in MEMS and Microsystems technology, and various designs have been realized through different fabrication processes. One type of microactuator commonly used is the scratch drive actuator (SDA) that is frequently fabricated by surface micromachining processes. An experimental investigation has been conducted on the characteristics of SDAs fabricated using the Cronos Microsystems MUMPs process. The motivation is to compare the response of SDAs located on the same die, and SDAs located on the different dies from the same fabrication batch. A high-speed imaging camera has been used to precisely determine important SDA characteristics such as step size, velocity, maximum velocity, and acceleration over long travel distance. These measurements are important from a repeatability point of view, and in order to fully exploit the potential of the SDA as a precise positioning mechanism. 2- and 3-stage SDAs have been designed and fabricated for these experiments. Typical step sizes varying from 7 nm at a driving voltage of 60 V to 23 nm at 290 V have been obtained.
The reports relates to a fluid based accelerometer and inclinometer and more particularly to a transducer which determines acceleration, inclination, position or velocity based on a temperature differential caused by the effect of acceleration on free or natural convection. This device includes a heater a d two temperature sensing elements mounted within a sealed enclosure containing a gas. The thermal sensors and temperature sensors were produced using a commercial CMOS process accelerometer based on above principle has been fabricated and tested.
In this paper, a new micromachined tunneling accelerometer is described. Using the bulk-silicon fabrication technology and the silicon/glass electrostatic bonding process, a sandwich structure tunneling accelerometer has been fabricated and tested. In order to reduce the low frequency noise, the feedback circuit has been improved by adding oscillator and demodulator. The first prototype has a resolution of approximately 1e-6g/ (root) Hz and can survive with at least 50g shocking.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.