Korth Kristalle GmbH

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A Family Business

Korth Kristalle GmbH is a family owned business employing highly qualified staff. The business was founded in 1949 by the physicist Dr. Karl Korth, who, at the University of Göttingen, was one of the first European scientists to grow crystals. Today the business is run by the third generation of the Korth family.

A lot has happened in our business since 1949! We have continued to develop and expand - both our premises and our technical capabilities - and we have invested heavily in the business. As a result, Korth Kristalle today enjoys a global reputation as a leader in the manufacture of optical components employing the latest technology – while nevertheless always staying true to our roots and founding principles.

An Overview of our History

1949 Foundation of the company by the physicist Dr. Karl Korth.
1962 New building at current location.
1968 Son Jörg U. Korth joins company after completing studies in chemistry.
1972 MERCK acquires company, creating new opportunities for research and development.
1974 Extension of factory including air conditioned polishing rooms.
1975 Acquisition of further Bridgman-Stockbarger (named after Percy Williams Bridgman and Donald C. Stockbarger) is a technique used for the production of large single crystals, like fluorides, silicon or gallium arsenide. A crucible filled with raw material powder is inserted into a furnace with different temperature zones. The raw material melts in the hotter part of the furnace. Crystallisation begins when the molten raw material is transferred into a cooler section of the oven. The seed crystals which are oriented along the axis of the crucible grow the fastest. To accelerate this process we use specially shaped crucibles. furnaces and premelting furnaces for fluoride crystal growth.
1983–1985 Acquisition of more land and buildings in neighbourhood. Expansion of crystal growth area into new building; separation of crystal growth and optical finishing. Growth of first big BaF2 crystals of 150 mm diameter. Investment in more smaller and medium sized furnaces for BaF2 projects (scintillators). Investment into new machinery for processing big crystals of BaF2, CaF2 and others.
1987 First processing of beam splitters by diamond turning. 
1988 Start of expansion of growth capacity for fluoride crystals (BaF2) for TAPS project. Setting up newly designed furnaces and control units. 
1989 New Kyropoulos furnace for development of high purity salt crystals for CO2 laser application.
1990–1992 Improving transmission of fluoride crystals for excimer laser application. 
1993 Takeover of company by Jörg U. Korth from MERCK in September (MBO). Foundation of KORTH KRISTALLE GMBH.
CaF2 crystal development for UV-stepper application at 193 nm. 
1995 Participation in several EU-projects for UV-crystal material improvement. Growth of 210 mm diameter fluoride crystals of improved quality from LiF, BaF2, MgF2 a.o. (SrF2, NaF diameter 150 mm). Investment in machinery for processing of crystal materials and in metrology equipment for crystal and surface measurement (quality assurance).  
2004 3rd generation of Korth family takes over responsibility for company together with their father: Anke Korth & Hauke Korth.
2006 New growth process for KRS-5 crystals. ISO 9001:2000 Certification.
2007 New optical workshop for large scale lens production from crystalline materials plus mounting of IR objectives.
2009 60th anniversary of company`s foundation. 
2010 Within the project SPHERE we delivered CaF2- and Fused Silica Components to be used as parts of a Polarimeter (component of the VLT, Chile)

Within the project GLORIA we manufactured Potassium Chloride Beamdisplacer and Compensator (dia 104mm). 

Relaunch of korth.de
For the first time we participated at the trade fair SPIE Photonics West located in San Francisco. From now on we plan to participate annualy.
Development of our inhouse characterization process.


Manufacturing of Potassium Bromide Components for the project "AOST" (exploring of marsmond Phobos)

Relocation of our quality control.
Recertification audit pursuant to EN ISO 9001:2008.
New framework for our production building

2013 Presentation of our new edited Compendium which is planned to be updated every two years for the trade fair LASER in Munich.
Investment in double-sided machines and a new workshop.
Development of CsI growth process.
Completion of project DIVE. 

2014 Production of KBr Components starting phase I of Project IASI-NG (exploring of atmosphere)
2015 Investment in a x-ray machine in order to develop our process of material characterisation.
Investment in three machines for sawing and grinding.
Jörg U. Korth retires and transfers all his shares to his children Hauke Korth and Anke Evers (both now sole managing directors and partners)
Amelie Otto becomes Director of Crystran Ltd.
Renovation of the office area.
Start of Phase II of Project IASI-NG (production of KBr components)
Improving of CNC polishing process
2016 Last delivery of KCl beamdisplacers within the project GLORIA
Investment in another CNC polishing machine and also in a new polishing workshop.
Purchase of a further saw.
Further investments in quality control equipment.
First summer party organized by our employees. Now an annual event at Korth Kristalle.
Hauke Korth and Anke Evers take over all Crystran shares of Jorg U. Korth (majority shareholder of Crystran Ltd.)
2017 Further investment in test equipment: Xonox Interferometer.
We succesfully completed Phase III of project IASI-NG (delivery of KBr Components)
2018 Start of expansion of growth capacity. Setting up addtional furnaces and control units.