TY  - JOUR
A1  - Werner, Frederik
A1  - Wagner, Torsten
A1  - Miyamoto, Ko-ichiro
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
T1  - High speed and high resolution chemical imaging based on a new type of OLED-LAPS set-up
JF  - Sensors and Actuators B: Chemical
N2  - Light-addressable potentiometric sensors (LAPS) are field-effect-based sensors. A modulated light source is used to define the particular measurement spot to perform spatially resolved measurements of chemical species and to generate chemical images. In this work, an organic-LED (OLED) display has been chosen as a light source. This allows high measurement resolution and miniaturisation of the system. A new developed driving method for the OLED display optimised for LAPS-based measurements is demonstrated. The new method enables to define modulation frequencies between 1 kHz and 16 kHz and hence, reduces the measurement time of a chemical image by a factor of 40 compared to the traditional addressing of an OLED display.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.snb.2011.12.102
SN  - 0925-4005
N1  - Part of special issue "Selected Papers presented at Eurosensors XXV"
VL  - 175
SP  - 118
EP  - 122
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Siqueira, Jose R.
A1  - Werner, Frederik
A1  - Bäcker, Matthias
A1  - Poghossian, Arshak
A1  - Zucolotto, Valtencir
A1  - Oliveira, Osvaldo N. Jr.
A1  - Schöning, Michael Josef
T1  - Layer-by-Layer Assembly of Carbon Nanotubes Incorporated in Light-Addressable Potentiometric Sensors
JF  - Journal of Physical Chemistry C. 113 (2009), H. 33
Y1  - 2009
SN  - 1932-7455
SP  - 14765
EP  - 14770
PB  - American Chemical Society
CY  - Washington, DC
ER  - 
TY  - JOUR
A1  - Siqueira, Jose R.
A1  - Maki, Rafael M.
A1  - Paulovich, Fernando V.
A1  - Werner, Frederik
A1  - Poghossian, Arshak
A1  - Oliveira, Maria C. F. de
A1  - Zucolotto, Valtencir
A1  - Oliveira, Osvaldo N. Jr.
A1  - Schöning, Michael Josef
T1  - Use of Information Visualization Methods Eliminating Cross Talk in Multiple Sensing Units Investigated for a Light-Addressable Potentiometric Sensor
JF  - Analytical Chemistry  (2010)
Y1  - 2010
SN  - 0003-2700
SP  - 61
EP  - 65
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, K.
A1  - Schöning, Michael Josef
A1  - Yoshinobu, T.
T1  - A high-density multi-point LAPS set-up using a VCSEL array and FPGA control
JF  - Procedia Chemistry. 1 (2009), H. 1
Y1  - 2009
SN  - 1876-6196
N1  - Proceedings of the Eurosensors XXIII conference ; Eurosensors 23
SP  - 1483
EP  - 1486
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, Ko-Ichiro
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - Development and characterisation of a compact light-addressable potentiometric sensor (LAPS) based on the digital light processing (DLP) technology for flexible chemical imaging
JF  - Sensors and Actuators B: Chemical
N2  - Chemical imaging systems allow the visualisation of the distribution of chemical species on the sensor surface. This work represents a new flexible approach to read out light-addressable potentiometric sensors (LAPS) with the help of a digital light processing (DLP) set-up. The DLP, known well for video projectors, consists of a mirror-array MEMS device, which allows fast and flexible generation of light patterns. With the help of these light patterns, the sensor surface of the LAPS device can be addressed. The DLP approach has several advantages compared to conventional LAPS set-ups, e.g., the spot size and the shape of the light pointer can be changed easily and no mechanical movement is necessary, which reduces the size of the set-up and increases the stability and speed of the measurement. In addition, the modulation frequency and intensity of the light beam are important parameters of the LAPS set-up. Within this work, the authors will discuss two different ways of light modulation by the DLP set-up, investigate the influence of different modulation frequencies and different light intensities as well as demonstrate the scanning capabilities of the new set-up by pH mapping on the sensor surface.
Y1  - 2012
U6  - http://dx.doi.org/10.1016/j.snb.2010.12.003
SN  - 0925-4005
N1  - Part of special issue "Eurosensors XXIV, 2010"
VL  - 170
SP  - 34
EP  - 39
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Werner, Frederik
A1  - Schusser, Sebastian
A1  - Spalthahn, Heiko
A1  - Wagner, Torsten
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
T1  - Field-programmable gate array based controller for multi spot light-addressable potentiometric sensors with integrated signal correction mode
JF  - Electrochimica Acta
N2  - A light-addressable potentiometric sensor (LAPS) can measure the concentration of one or several analytes at the sensor surface simultaneously in a spatially resolved manner. A modulated light pointer stimulates the semiconductor structure at the area of interest and a responding photocurrent can be read out. By simultaneous stimulation of several areas with light pointers of different modulation frequencies, the read out can be performed at the same time. With the new proposed controller electronic based on a field-programmable gate array (FPGA), it is possible to control the modulation frequencies, phase shifts, and light brightness of multiple light pointers independently and simultaneously. Thus, it is possible to investigate the frequency response of the sensor, and to examine the analyte concentration by the determination of the surface potential with the help of current/voltage curves and phase/voltage curves. Additionally, the ability to individually change the light intensities of each light pointer is used to perform signal correction.
Y1  - 2011
U6  - http://dx.doi.org/10.1016/j.electacta.2011.03.012
SN  - 0013-4686
VL  - 56
IS  - 26
SP  - 9656
EP  - 9660
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, Ko-ichiro
A1  - Ackermann, Hans-Josef
A1  - Yoshinobu, Tatsuo
A1  - Schöning, Michael Josef
T1  - FPGA-based LAPS device for the flexible design of sensing sites on functional interfaces
JF  - Physica Status Solidi (A). 207 (2010), H. 4
Y1  - 2010
SN  - 1862-6300
N1  - Special Issue: Engineering of Functional Interfaces EnFI 2009
SP  - 844
EP  - 849
ER  - 
TY  - JOUR
A1  - Werner, Frederik
A1  - Krumbe, Christoph
A1  - Schumacher, Katharina
A1  - Groebel, Simone
A1  - Spelthahn, Heiko
A1  - Stellberg, Michael
A1  - Wagner, Torsten
A1  - Yoshinobu, Tatsuo
A1  - Selmer, Thorsten
A1  - Keusgen, Michael
A1  - Baumann, Marcus
A1  - Schöning, Michael Josef
T1  - Determination of the extracellular acidification of Escherichia coli by a light-addressable potentiometric sensor
JF  - Physica status solidi (a) : applications and material science. 208 (2011), H. 6
Y1  - 2011
SN  - 1862-6319
SP  - 1340
EP  - 1344
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Werner, Frederik
A1  - Miyamoto, Ko-Ichiro
A1  - Schöning, Michael Josef
A1  - Yoshinobu, Tatsuo
T1  - A high-density multi-point LAPS set-up using a VCSEL array and FPGA control
JF  - Sensors and Actuators B: Chemical. 154 (2011), H. 2
Y1  - 2011
SN  - 1873-3077
N1  - EUROSENSORS XXIII
SP  - 124
EP  - 128
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Wagner, Torsten
A1  - Miyamoto, K.
A1  - Werner, Frederik
A1  - Schöning, Michael Josef
A1  - Yoshinobu, T.
T1  - Flexible electrochemical imaging with “zoom-in” functionality by using a new type of light-addressable potentiometric sensor
Y1  - 2011
N1  - 2011 16th International Solid-State Sensors, Actuators and Microsystems Conference (TRANSDUCERS) , Date: 5-9 June 2011
SP  - 2133
EP  - 2135
PB  - IEEE
CY  - New York
ER  -