Takahashi Seisakusho
From Wikipedia, the free encyclopedia
Takahashi Seisakusho is a Japanese manufacturer of telescopes and related equipment, such as eyepieces and mounts. Often known simply as 'Tak', the brand is especially noted amongst amateur astronomers for its range of apochromatic refractors.
Takahashi pioneered the use of fluorite crystal in place of one of the glass elements in the objective lens of an astronomical telescope, although this material had previously been used in other optical devices. [1] The company's name would become synonymous with the use of this type of crystal. In recent years however, Takahashi has produced some telescopes using FPL-53 glass[2] in place of fluorite in the objective lens, and claims that this design has certain performance advantages.[3] This type of glass has already been used by competitors such as Astro-Physics[4], Televue and TMB Optical, although Takahashi has stated in the past that any material other than fluorite crystal is inferior.[5] High-performance glass that contains fluorine should not be confused with fluorite crystal, which is not glass.
Although Takahashi became famous for its apochromatic refractors, it also produces a range of reflecting telescopes.
[edit] References
- ^ Lizaso, IƱaki. "Fluorite Refracting Telescopes".
- ^ FPL-53 is a type of glass manufactured by Ohara GmbH. "Optical Glass for Astronomical Applications".
- ^ Takahashi Seisakusho. "Takahashi Triplet Lens".
- ^ Back, Thomas M. "A Brief History of Astro-Physics Lenses".
- ^ Takahashi Seisakusho. "The Fluorite Advantage".