X-ray data acquisition systems for Airport Security

1

• X-ray data acquisition systems for Airport
  Security
• J M Homer Electron Tubes Ltd

2
Electron Tubes Ltd

• Specialises in X-ray and light detection systems
• UK based company
• Products
• X-ray data acquisition systems
• Light detection modules
• Photomultipliers
• Customers
• Security systems
• Instrumentation
• NDT systems
• Scientific research (HE Physics and Space)

3
Airport security applications
Carry-on baggage scanner
Checked baggage scanner
Large baggage or container scanner
4
System types
Carry-on baggage scanner Linescan system
Checked baggage scanner CT system
Large baggage or container scanner Multi-view
linescan system
5
Personal X-ray scanning
Compton backscatter using photomultipliers
6
X-ray detectors
Material Thickness mm Energy Range mm Signal output Signal decay time
Silicon 0.3 5 25keV Highest signal, direct conversion 1µs
Gadox (Tb) 140gm/cm2 20 100keV Similar to CsI 2 3ms
CsI (Tl) 4.5mm 40 160keV Best light output 2 components, long decay tail
CdWO4 2.5mm 30mm 150keV 9Mev 25 of CsI 20µs
7
X-ray linescan system
8
Single energy and dual energy detectors
9
X-ray CT system
10
Requirements of data acquisition system

• Large number of channels, 2000 to 20000
• Sub-millisecond scan time
• Wide dynamic range
• Digital output
• Low noise
• Low cost

11
XDAS system

• charge integrating method
• simultaneous data acquisition and read-out
• on board sub-sampling and data summation
• links to PC via USB2 or PCI-7300A data I/O card
• s/w controllable via RS485 interface
• system read-out rate 5MB/s

12
Single Channel of ASIC
13
XDAS module block diagram
14
XDAS system block diagram
15
XDAS V1X system

• One digital board drives 20 detector head boards
  with 2560 channels
• Multiple digital boards allow up to 30000
  channels
• System read-out rate up to 20MHz
• Same capability as original XDAS system
• Lower cost

16
XDAS-V1X detector head board
17
XDAS-V1X signal processing board block diagram
18
XDAS-V1X system block diagram
19
XDM System

• modular system of any length
• 6mm detector pitch
• suitable for use with high energy applications
  using Linacs
• high charge capacity (1000pC)
• 20-bit output
• 1 bit of noise
• high speed serial link to CPU
• systems designed to order

20
summary

• modular X-ray data acquisition systems
• designed for use with linescan and CT X-ray
  systems
• large number of channels
• fast
• low noise
• low cost per channel
• digital output
• can be configured to meet specific requirements

21
solutions in light detection