789 research outputs found
Lab-on-a-chip for biological fluids analysis by spetrophotometry
The healthcare sector is nowadays one of the most dynamic and where the novelty is a strategic and operational imperative. The possibility of increase the quantity and quality of clinical analysis, performed with instantaneous results and outside the clinical laboratories, contributes to a better quality in the health care services and also a better efficiency in the clinical and administrative processes [1]. This possibility can be achieved with the presented lab-on-a-chip for spectrophotometric analysis of biological fluids. It allows the selective measurement of the concentration of several biomolecules in biological fluids, with instantaneous results, at any location, with small quantities of reagents and samples and with low-cost. That measurement is based on colorimetric detection by the optical absorption in a part of the visible spectrum defined by the reaction of the specific biomolecule with a specific reagent. The device comprises a highly efficient and selective optical filtering and colorimetric detection system. This system allows the measurement with a regular white light illumination, thus avoiding the use of complex and expensive analysis systems like the ones that comprise spectrophotometers, for example. This feature highly facilitates portability and ensures analysis within consultation time, at a patient house (allowing a first trial) and in clinical laboratories or hospitals.Fundação para a Ciência e a Tecnologia (FCT) SFRH/BD/1281/2000
Escola de Engenharia da Universidade do Minho - Projecto IN2TEC.
Centro Algoritmi da Universidade do Minh
High-selectivity single-chip spectrometer for operation at visible wavelengths
A micro-spectrometer has been realized based on an array of Fabry-Perot thin-film optical resonators. The 16 channel micro-spectrometer is IC fabrication compatible and
operates in the visible spectral range with an inter-channel shift of 6 nm. Each of the channels is sensitive in a single peak with FWHM of 16 nm. A FWHM < 2 nm and finesse
of 40 for narrowband operation is demonstrated.STW - Project DEL 55.3733.
TUDelft.
Fundação para a Ciência e Tecnologia - Praxis XXI-BD/5181/95
Micromachined fabry-perot optical filters
The design, fabrication and measured characteristics of micromachined Fabry-
Perot (F-P) optical filters for the visible spectral range are presented. Silver films
of 40-50 nm thickness, evaporated on a 300 nm thick low-stress silicon nitride
membrane, are used as high-quality mirrors. Two parallel mirrors, with a square
aperture of up to 2x2 mm2 and initial cavity gap of 1.2 µm, form a tunable Fabry-
Perot optical filter. One of the mirrors is fixed the other is under tension on a
movable Si frame, which is electrostatically deflected to control the mirror
spacing and parallelism. Results are compared with non-tunable F-P filters that
are composed of an Ag/SiN/Ag or Ag/SiO2/Al layer stack. The FWHM of 40 nm
(tunable filter) and 16 nm (non-tunable filter) have been achieved.STW - Project DEL 55.3733.
Junta Nacional de Investigação Científica e Tecnológica - PRAXIS XXI-BD/5181/95
High-selectivity single-chip spectrometer in silicon for operation at visible part of the spectrum
A microspectrometer has been realized based on an
array of Fabry–Perot optical thin-film filters. The 16-channel microspectrometer
is compatible with IC fabrication methods and
operates in the visible spectral range with an interchannel shift
of 6 nm. Each of the channels is sensitive in a single peak with
full-width-half-maximum (FWHM) of 16 nm. Also aFWHMbelow
2 nm and finesse of 40 for narrow band operation is demonstrated.
The device can easily be tuned during fabrication to cover a different
spectral band only by adjusting the etching times without
affecting the device layout. Such a device is extremely suitable for
applications in microsystems because of its small size, high spectral
selectivity, and low cost. Microspectrometers for the UV and
IR regions are also feasible using this technique.Fundação para a Ciência e a Tecnologia (FCT
Silver-based reflective coatings for micromachined optical filters
Silver films of 40 nm thickness, evaporated on a 300 nm thick low-stress silicon nitride layer, are used as high-quality mirrors operating in the visible and near IR spectral range. Application of a silicon nitride membrane under tension, placed within a square Si
frame after bulk micromachining, improves the initial mirror flatness. Two parallel mirrors,
each with square aperture of up to 2x2 mm2 and an electrostatically controlled spacing,
form a tunable Fabry–P´erot optical filter. Investigation of the silver-based reflective coatings, and mirror characterization, including influence of bulk micromachining, are presentedFundação para a Ciência e a Tecnologia FC
Bulk-micromachined tunable fabry–perot microinterferometer for the visible spectral range
The design, fabrication and measured characteristics of a bulk-micromachined tunable Fabry–Perot microinterferometer (FPMI) for the visible spectral range are presented. The FPMI is formed by two parallel 40 nm thick silver mirrors supported by a 300 nm low tensile
stress silicon nitride membrane with a square aperture (side length of 2 mm) and initial cavity gap of 1.2 µm. One of the mirrors is fixed,
the other is under tension on a movable Si frame, which is electrostatically deflected, using several distributed electrodes, to control
cavity spacing and mirror parallelism. Performance achieved is: high flatness of the mirrors (λ/10 for the visible part of the spectrum), low control voltages (<21 V for 450 nm deflection) and simple fabrication.Fundação para a Ciência e Tecnologia (FCT
A local bus for MCM-based microinstrumentation systems
A local bus is described which is designed for use in a multi-chipcomposed
microinstrumentation system. The bus is able to transmit a digital
code, bitstream, analog voltage, frequency, duty-cycle and also provides
calibration facilities, service request and interrupt request for the smart
sensors. Corresponding sensor bus interface was implemented in a 1.6 m
CMOS process and successfully tested in a local sensor network.Junta Nacional de Investigação Científica e Tecnológica - Praxis XXI-BD/5181/95.
STW - Project DEL 55.3733.
TUDelft
A microinstrumenation system for industrial applications
This paper describes the development of a
microinstrumentation system in silicon containing all the
components of the data acquisition system, such as sensors,
signal-conditioning circuits, analog-digital converter, interface
circuits, sensor bus interface, and an embedded
microcontroller (MCU). The microinstrumentation system is
to be fabricated using the Multi-Chip-Module (MCM)
technology based on a chip-level infrastructure. A standard
silicon platform is the floorplan for individual smart sensor die
attachment and an on-chip local sensor bus interface, testing
facilities, optional compatible sensors (such as thermal
sensors). The microinstrumentation system is controlled by a
MCU with several modes of low-power operation (inclusive
stand-by mode). As the intended application requires a huge
amount of data-processing, a RISC-type MCU architecture is
to be used. The MCU communicates with the front-end sensors
via a two-line (clock and data lines) intramodule sensor bus
(Integrated Smart Sensor bus). The sensor scan rate is
adaptive and can be event triggered. This upgraded version of
the ISS bus allows: service and interrupt request from the
sensors, test and calibration facilities. However, the additional
functionality requires a third line. The MCU also controls the
power consumption and the thermal budget of all system. This
paper also presents three applications for the
microinstrumentation system: condition monitoring of
machines, an inertial navigation system and a miniature
spectrometer.STW - Project DEL55.3733.
TUDelft.
Junta Nacional de Investigação Científica e Tecnológica - Praxis XXI-BD/5181/95
A local bus for multi-chip-module-based microinstrumentation systems
A local smart bus is described which is designed for use in muti-chip-composed microinstrumentation system. The bus is able to transmit a digital code, bitstream, analog voltage, frquency, duty-cycle and also provides calibration facilities, service request and interrupt request modes.FC
A low-power low-voltage digital bus interface for MCM-based microsystems
Comunicação apresentada na 23rd European Solid-State Circuits Conference (ESSCIRC '97), Southampton, UK, 16-18 September 1997.This paper describes a digital local bus interface, which is designed for use
in a multi-chip-composed microsystem. The chip area using a CMOS 1.6mm
n-well technology is 1mm2. Power consumption at 5V@100kHz is less than
500mW and for 5V@4MHz less than 2mW due to a smart power management
of all functional blocks. The bus interface is able to transmit a digital code,
bitstream, analog voltage, frequency, duty-cycle and also provides calibration
facilities, service request and interrupt request for the smart sensors or
microactuators.Junta Nacional de Investigação Científica e Tecnológica - Praxis XXI-BD/5181/95.
STW - Project DEL 55.3733.
TUDelft
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