Under Howard Grubb, the Grubb Telescope Company gained an even greater reputation for quality
optical instruments. Grubb was also known for building accurate electrically driven
clock drives for
equatorial mounted telescopes. Some of the telescopes produced by Howard Grubb include the 27-inch refractor for the
Vienna Observatory (1878), the 10-inch refractor at
Armagh Observatory (1882), the 28-inch refractor at the
Royal Observatory, Greenwich – the UK's largest refractor (1893), and the 10-inch refractor at
Coats Observatory, Paisley (1898). In 1887, Grubb's firm built seven normal
astrographs for the
Carte du Ciel international photographic star catalogue project, 13-inch
refracting telescopes all designed to produce uniform photographic plates. In 1900, Grubb invented the
reflector or "reflex" sight, a non-magnifying optical
sight that uses a
collimator to allow the viewer looking through the sight to see an illuminated image of a
reticle or other pattern in front of them that stays in alignment with the device the sight is attached to (
parallax free). This type of sight has come to be used on all kinds of weapons from small
firearms to
fighter aircraft. It is also at the heart of all modern
head-up displays. During the
First World War, the Grubb factory was in demand for the production of telescopic gun-sights and during this time he was credited with perfecting a
periscope design for
Royal Navy submarines. == See also ==