Seiler Instrument & Mfg . Co . Seiler Instrument & Mfg . Co . is a full service contract manufacturer specializing in optical fire control equipment as well as a major distributor of surveying software and instruments , microscopes , and Zeiss planetariums . There are several main divisions within the company which include Manufacturing , Geospatial - Survey , Microscope , Planetarium , and Night Vision . It is headquartered in St . Louis , Missouri with Geospatial - Survey sales offices located in Kansas City , Illinois , Nebraska , Indiana , and Wisconsin . History . Seiler Instrument was founded in 1945 by Eric H . Seiler and his wife Dora L . Seiler . Seiler had been trained in the field of optical design and construction by the Zeiss Jena School of Fine Optics in Jena , Germany . He had originally worked for Zeiss Jena , the first incarnation of what is now Carl Zeiss AG , but continued to work in the optical field for the David White company in Wisconsin after emigrating to the United States . Seiler began his own optical company at 922 Pine Street which specialized in repairing existing survey instruments . Since this time , the company ' s focus has shifted toward designing or retailing survey , military , medical , and planetarium systems . Manufacturing . Seiler Instrument ’ s Manufacturing Division specializes in manufacturing precision optical instruments and components primarily for the United States Military . Seiler is the Original Equipment Manufacturer of the optical fire control used on all United States howitzer and mortar systems as well as many howitzer systems used around the world . From start to finish , Seiler is responsible for the machining , assembly , and testing of all components of the optical fire control system . Along with manufacturing optical instrument assemblies , Seiler also specializes in refurbishing artillery optical fire control equipment which can extend the life of a weapon system . Geospatial - Survey . Seiler Instrument ’ s Geospatial - Survey Division is segmented into various industries : Survey , Architecture , Engineering , Design Build Construction , and Mapping GIS / GPS . Seiler specializes in product sales , training , implementation , support , rentals , and repairs . They are one of the largest distributors in the United States for Trimble Navigation Limited / Trimble® and an Autodesk ® Silver Partner Reseller . Seiler is an Authorized Autodesk Training Center , Autodedsk Consulting Specialized , and AIA CES provider . There are six office locations across the Midwestern United States . Seiler Instrument is also a Trimble Preferred Service Provider with authorized service and repair centers located in St . Louis , Indianapolis , and Milwaukee . Microscope . Seiler Instrument ’ s Microscope Division was created in 1950 when Seiler formed an agreement with Carl Zeiss ( Jena ) to distribute their microscope line in North America . After many successful years as a North American dealer for Zeiss , Seiler and Zeiss parted ways . This split allowed Seiler to create a new microscope to compete with the Zeiss product line and to develop partnerships in Germany , South America , and Asia . Seiler ’ s Microscope Division provides high quality optics and services to the medical and dental industry . Seiler offers a full line of medical microscope products including : Colposcopes , Ear Nose and Throat ( ENT ) , Audiology , Compound and Laboratory Microscopes , Multidisciplinary Surgery Microscopes and Surgical Loupes . They also offer a complete line of dental microscopy products including : Surgical Microscopes , Dental Loupes , Loupe Lights , and Dental Stools . Planetarium . In 1987 , Seiler Instrument and Carl Zeiss reunited through their planetarium line , and the Seiler Instrument Planetarium Division was created . Seiler Instrument is the sole distributor and first point of contact for sales , service , and repairs on all Carl Zeiss Planetariums in the United States and Canada . Over 600 Zeiss Planetariums around the world have been installed to date for the purposes of simulation , education , and entertainment . Seiler has installed and serviced these projectors in planetariums and science centers such as the Noble Planetarium at the Fort Worth Museum of Science and History . Night Vision . Seiler ’ s Night Vision Division manufactures and distributes day and night vision precision rifle scopes under the name VISIONMASTER® for the military , law enforcement agencies , and hunters . The VISIONMASTER® eliminates the need to maintain a dedicated night vision weapon system and a dedicated day weapon system . These rifle scopes allow marksmen to use a single weapon system 24 hours a day . When light levels fall below the minimum required for day operations , the VISIONMASTER® can be switched from a day scope to a night vision scope in less than 30 seconds with no tools and no shift in point of impact .