Synthesis of science and technology
Successful demonstration of the ITER Optical Pellet Diagnostic concept.
In 2020 Fusion Instruments won a tender at the ITER international fusion experiment for design and demonstration of the concept of an optical pellet diagnostic for the ITER Shattered Pellet Injector system. Our Hybrid detector system consist of an APDCAM-10G camera with a custom optics and fiber array “scanning” the cryogenic pellets flying with 100-800 m/s behind a 100 mm diameter window. From the individual detector signals the camera’s FPGA processor generates triggers for 3 simple CMOS cameras and associated 200W/100 ns laser pulses which take still images of the pellet. In July-November 2022 this concept was demonstrated in the ITER Shattered Pellet Injector support laboratory of the Centre for Energy Research. The image below shows the images with two views of a 28.5 x 55 mm Hydrogen pellet flying with 500 m/s velocity. Below the APDCAM signals are plotted with the trigger time.
An APDCAM-10G 8x16A camera is in the core of Gas Puff Imaging (GPI) diagnostic on the Wendelstein 7-X stellarator (September, 2022)
Gas Puff Imaging (GPI) is a fusion diagnostic technique where gas is blown to the surface of the plasma and the resulting visible light radiation is used for detecting plasma turbulence. This technique requires MHz frame rate and large Etendue observation system but low spatial resolution suffices. The 1.6 mm APD pixels of the APDCAM family perfectly suit this aim, therefore the Massachusetts Institute of Technology selected Fusion Instrument’s APDCAM-10G family as the detector on their GPI system on the world’s largest stellarator experiment, Wendelstein 7-X. The diagnostic started to operate in commissioning phase of the OP2.1 campaign.
Fusion Instruments developed neutron detector amplifier for Mirrotron Kft. (December, 2021)
Based on its detector electronics experience Fusion Instruments developed a 21 channel neutron detector amplifier device has Mirrotron Kft, a manufacturer of neutron instrumentation. The device takes 21 analog inputs and produces digital output pulses for processing by an FPGA electronics. The amplifier box has RS-422 communication to the PC, where comparator levels can be set and information on the device can be queried.
Fusion Instruments builds prototype of the ITER Shattered Pellet Injector optical diagnostic (April, 2020)
APDCAM measures fast ion losses on ASDEX Upgrade (November, 2019)
First measurement results from an APDCAM camera installed in a new Fast Ion Loss Detector (FILD) diagnostic on the ASDEX Upgrade tokamak have been published in the Journal of Instrumentation. Light signal fluctuations in the 100 kHz range reveal fast particles ejected from the plasma by Magnetohydrodynamic waves.
APDCAM with MPPC matrix installed on the JET tokamak (November, 2018)
A 4×8 pixel APDCAM camera has been operating in the Li-beam diagnostic of the JET tokamak since many years. An optimization study revealed that the recently available MPPC detector matrices would improve the Signal to Noise Ratio in this experiment, especially in the Scrape Off Layer of the plasma and during gas calibration when the light signal is in 10^7 – 10^8 ph/s range. First measurements showed the expected improvement and now the diagnostic can provide routine calibrated measurement data.
64 channel fibre-coupled APDCAM-10G (September, 2017)
A new version of the APDCAM-10G family has been developed under the name APDCAM-10G-FC64. It features 64 individual detectors, which can be a mixture of up to 4 different APD and/or MPPC detector types. Light is coupled to each detector through a fibre cable connected to standard SMA connectors. This device enables fast spectroscopy or other applications where strongly varying light level is expected on different channels, thus a choice of APD/MPPC enables optimization of the Signal to Noise Ratio. Below three different APDCAM-10G front faces are shown: 4×32, 8×16, FC64.
The first APDCAM-10G-FC64 camera is installed in the Alkali Beam diagnostic of the Wendelstein 7-X stellarator
1 Gbit ADC is ready to ship (September, 2016)
A 32 channel, 14 bit, 2 MHz ADC unit is available now with 1 Gbit PC communication. For details please contact us. A 32-128 channel, 14 bit 4-6 MHz (10 Gbit communication) ADC box will also be ready in a few month time.
APDCAM with MPPC detectors (July, 2016)
APDCAM cameras are now also available with the new Hamamatsu Multi Pixel Photon Counter (MPPC) detectors. For a comparison of standard APD detectors with MPPC please read our white paper on this subject.