10,006 research outputs found
Prototype ATLAS IBL Modules using the FE-I4A Front-End Readout Chip
The ATLAS Collaboration will upgrade its semiconductor pixel tracking
detector with a new Insertable B-layer (IBL) between the existing pixel
detector and the vacuum pipe of the Large Hadron Collider. The extreme
operating conditions at this location have necessitated the development of new
radiation hard pixel sensor technologies and a new front-end readout chip,
called the FE-I4. Planar pixel sensors and 3D pixel sensors have been
investigated to equip this new pixel layer, and prototype modules using the
FE-I4A have been fabricated and characterized using 120 GeV pions at the CERN
SPS and 4 GeV positrons at DESY, before and after module irradiation. Beam test
results are presented, including charge collection efficiency, tracking
efficiency and charge sharing.Comment: 45 pages, 30 figures, submitted to JINS
A review of advances in pixel detectors for experiments with high rate and radiation
The Large Hadron Collider (LHC) experiments ATLAS and CMS have established
hybrid pixel detectors as the instrument of choice for particle tracking and
vertexing in high rate and radiation environments, as they operate close to the
LHC interaction points. With the High Luminosity-LHC upgrade now in sight, for
which the tracking detectors will be completely replaced, new generations of
pixel detectors are being devised. They have to address enormous challenges in
terms of data throughput and radiation levels, ionizing and non-ionizing, that
harm the sensing and readout parts of pixel detectors alike. Advances in
microelectronics and microprocessing technologies now enable large scale
detector designs with unprecedented performance in measurement precision (space
and time), radiation hard sensors and readout chips, hybridization techniques,
lightweight supports, and fully monolithic approaches to meet these challenges.
This paper reviews the world-wide effort on these developments.Comment: 84 pages with 46 figures. Review article.For submission to Rep. Prog.
Phy
Trends in Pixel Detectors: Tracking and Imaging
For large scale applications, hybrid pixel detectors, in which sensor and
read-out IC are separate entities, constitute the state of the art in pixel
detector technology to date. They have been developed and start to be used as
tracking detectors and also imaging devices in radiography, autoradiography,
protein crystallography and in X-ray astronomy. A number of trends and
possibilities for future applications in these fields with improved
performance, less material, high read-out speed, large radiation tolerance, and
potential off-the-shelf availability have appeared and are momentarily matured.
Among them are monolithic or semi-monolithic approaches which do not require
complicated hybridization but come as single sensor/IC entities. Most of these
are presently still in the development phase waiting to be used as detectors in
experiments. The present state in pixel detector development including hybrid
and (semi-)monolithic pixel techniques and their suitability for particle
detection and for imaging, is reviewed.Comment: 10 pages, 15 figures, Invited Review given at IEEE2003, Portland,
Oct, 200
Development of a real-time full-field range imaging system
This article describes the development of a full-field range imaging system employing a high frequency amplitude modulated light source and image sensor. Depth images are produced at video frame rates in which each pixel in the image represents distance from the sensor to objects in the scene.
The various hardware subsystems are described as are the details about the firmware and software implementation for processing the images in real-time. The system is flexible in that precision can be traded off for decreased acquisition time. Results are reported to illustrate this versatility for both high-speed (reduced precision) and high-precision operating modes
Light field super resolution through controlled micro-shifts of light field sensor
Light field cameras enable new capabilities, such as post-capture refocusing
and aperture control, through capturing directional and spatial distribution of
light rays in space. Micro-lens array based light field camera design is often
preferred due to its light transmission efficiency, cost-effectiveness and
compactness. One drawback of the micro-lens array based light field cameras is
low spatial resolution due to the fact that a single sensor is shared to
capture both spatial and angular information. To address the low spatial
resolution issue, we present a light field imaging approach, where multiple
light fields are captured and fused to improve the spatial resolution. For each
capture, the light field sensor is shifted by a pre-determined fraction of a
micro-lens size using an XY translation stage for optimal performance
Advances on CMOS image sensors
This paper offers an introduction to the technological advances of image sensors designed using
complementary metalâoxideâsemiconductor (CMOS) processes along the last decades. We review
some of those technological advances and examine potential disruptive growth directions for CMOS
image sensors and proposed ways to achieve them. Those advances include breakthroughs on
image quality such as resolution, capture speed, light sensitivity and color detection and advances on
the computational imaging. The current trend is to push the innovation efforts even further as the
market requires higher resolution, higher speed, lower power consumption and, mainly, lower cost
sensors. Although CMOS image sensors are currently used in several different applications from
consumer to defense to medical diagnosis, product differentiation is becoming both a requirement and
a difficult goal for any image sensor manufacturer. The unique properties of CMOS process allows the
integration of several signal processing techniques and are driving the impressive advancement of the
computational imaging. With this paper, we offer a very comprehensive review of methods,
techniques, designs and fabrication of CMOS image sensors that have impacted or might will impact
the images sensor applications and markets
Lensless wide-field fluorescent imaging on a chip using compressive decoding of sparse objects.
We demonstrate the use of a compressive sampling algorithm for on-chip fluorescent imaging of sparse objects over an ultra-large field-of-view (>8 cm(2)) without the need for any lenses or mechanical scanning. In this lensfree imaging technique, fluorescent samples placed on a chip are excited through a prism interface, where the pump light is filtered out by total internal reflection after exciting the entire sample volume. The emitted fluorescent light from the specimen is collected through an on-chip fiber-optic faceplate and is delivered to a wide field-of-view opto-electronic sensor array for lensless recording of fluorescent spots corresponding to the samples. A compressive sampling based optimization algorithm is then used to rapidly reconstruct the sparse distribution of fluorescent sources to achieve approximately 10 microm spatial resolution over the entire active region of the sensor-array, i.e., over an imaging field-of-view of >8 cm(2). Such a wide-field lensless fluorescent imaging platform could especially be significant for high-throughput imaging cytometry, rare cell analysis, as well as for micro-array research
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