Photek Ltd

Photek Ltd

Photek factory
Type	Private
Industry	Electronics
Founded	(September 1, 1991)
Founders	Jon Howorth, Ralph Powell, Martin Ingle, Geoff Holt, Mehmet Madakbas
Headquarters	26 Castleham Road, St Leonards-on-Sea, UK
Key people	Gareth Jones (Managing director) Martin Ingle (Technical Director) James Milnes (R&D Manager) Panos Kapetanopoulos (Sales Manager)
Products	Photomultiplier tubes Imaging devices Imaging and analyzing systems
Number of employees	55 (2016)
Website	Official website

Photek Limited is a specialist manufacturer and global supplier of vacuum based tubes and camera systems for photon detection. Photek manufacture image intensifiers, solar-blind detectors, photomultipliers, streak tubes and a range of associated electronics and camera systems. The company was founded in 1991 by Jon Howorth, Ralph Powell, Martin Ingle, Geoff Holt and Mehmet Madakbas.

Photek's manufacturing specialty is fast time-resolution devices using micro-channel plates. Fusion plasma diagnostics collaborations^[1] with AWE have improved time resolution to less than 100ps for devices with micro-channel plate amplification.^[2] Detectors without an MCP, such as vacuum photo-diodes, can go as low as 55ps time resolution.^[3] Specialist devices, such as streak tubes, achieve an even better resolution of 1 picosecond or less ^[4] but must sacrifice one spatial dimension for timing information.

Notable Projects

Space Missions

Photek detectors have been used in several space missions through collaborations with academic institutions such as the University of Leicester:

• Image Intensifiers (CsI Far-UV, CsTe Near-UV, Alkali-Antimonide Visible) for the Ultra-Violet Imaging Telescope (UVIT) on Astrosat. ISRO - Launched September 28, 2016.^[5]
• Scanning Image Spectrograph (CsI Far-UV image intensifier), part of the Special Sensor Ultraviolet Spectrographic Imager (SSUSI) on DMSP satellites since 2003.^[6] NASA - Launched October 18, 2003;^[7] November 04, 2006;^[8] October 18, 2009;^[9] April 14, 2014.^[10]
• UV Spectrograph (CsI Far-UV image intensifier), part of the Miniature Integrated Camera And Spectrometer (MICAS) on Deep Space 1. NASA - Launched October 24, 1998.
• Scintillating Optical Fibre Trajectory (SOFT) Detector (Alkali-Antimonide Visible image intensifer), part of the Cosmic Ray Isotope Spectrometer (CRIS) on Advanced Composition Explorer (ACE). NASA - Launched August 25, 1997.^[11]

Particle Detectors

Photek are partners in the TORCH project at CERN to produce a new detector for the LHCb upgrade.^[12][13][14] A concurrent collaboration with Arradiance, USA to develop protective vacuum coatings for electron multipliers has shown ALD-coated photomultipliers can cope with the much higher flux (5C.cm^-2) required in particle detector applications.^[15]

Velocity Map Imaging

Photek were the first to commercialise Velocity Map Imaging (VMI) technology,^[16] offering VMI ion optics and related instrumentation for physical chemistry^[17] and laser physics research applications.^[18] VMI is a variation of charged-particle imaging that offers high velocity resolution, unlocking information on fundamental chemical structure or the characteristics of the intense, ultra-short laser-particle interaction. VMI was used as a ‘quantum microscope’ to take the first ever ‘photograph’ inside a hydrogen atom in 2013.^[19][20]

Unusual Applications

• Fluorescence imaging of Michaelangelo's David, proves a non-destructive method for chemical testing of artwork surfaces.^[21] Using an image intensifier with 5ns time windows after a 1ns 337 nm laser exposure the fluorescence decay was measured over 100ns to obtain a map of the different surface chemicals to reveal ancient repairs and preservation methods.
• Bio-photon emission can provide information about chemical processes in living organisms. The low intensity emissions can even be detected after attenuation through other tissue when using an image intensifier with sufficient gain. An image intensifier with 200 um spatial resolution and 10us time resolution was used to analyse the effects of hyperoxia by the bio-photon emission from oxidation reactions. This damage is of particular concern in the brain as it consumes 20% of the oxygen in the body and is composed largely of fatty tissues that are susceptible to this oxidative stress.^[22]

References

1. "GA Diagnostic Improvements" (PDF). Retrieved March 18, 2016.
2. "AWE time resolution". Retrieved March 18, 2016.
3. "Ultra high speed PMT" (PDF). Retrieved March 20, 2016.
4. "Streak camera speed". Retrieved March 18, 2016.
5. "UVIT detector" (PDF). Retrieved March 19, 2016.
6. "SSUSI detector". Retrieved March 22, 2016.
7. "SSUSI Photek 1". Retrieved March 22, 2016.
8. "SSUSI Photek 2". Retrieved March 22, 2016.
9. "SSUSI Photek 3". Retrieved March 22, 2016.
10. "SSUSI Photek 4". Retrieved March 22, 2016.
11. "SOFT detector". Retrieved March 19, 2016.
12. "TORCH Overview" (PDF). Retrieved March 19, 2016.
13. "LHCb TORCH upgrade". Retrieved March 18, 2016.
14. "LHCb TORCH upgrade 2" (PDF). Retrieved March 18, 2016.
15. "TORCH Lifetime" (PDF). Retrieved March 19, 2016.
16. "VMI homepage". Retrieved March 22, 2016.
17. "Uni of Oxford Dynamics Group". Retrieved March 22, 2016.
18. "VMI EU applications". Retrieved March 22, 2016.
19. "Fox News hydrogen atom". Retrieved March 22, 2016.
20. "Hydrogen Atoms under Magnification: Direct Observation of the Nodal Structure of Stark States". Retrieved March 22, 2016.
21. "Fluorescence Lifetime Imaging and Fourier Transform Infrared Spectroscopy of Michelangelo's David". Retrieved March 18, 2016.
22. "In vivo imaging of spontaneous ultraweak photon emission from a rat's brain correlated with cerebral energy metabolism and oxidative stress.". Retrieved March 18, 2016.

External links

• Photek Ltd website
• Lumintek camera system
• Velocitas Velocity Map Imaging system
• Sydor Technologies
• German Image Detector Systems