UVOT  INSTRUMENT

The largest part of  the UltraViolet/Optical Telescope (UVOT) is the two metre long Telescope Module (TM). It was designed and built by the Mullard Space Science Laboratory (MSSL) in Surrey.

The Telescope Module consists of four sections (click image for enlarged view) :

• the external baffle, which reduces the straylight inside the telescope
the telescope, which contains the primary and secondary mirrors

• the detector module, which houses the rest of the optical system and its associated electronics

• the power supply module, on which is mounted the power supply unit for the TM and the external connector panel

This modular approach allowed the sections to be independently assembled and facilitated the alignment of the optical elements.

At the open end of the external baffle is the UVOT door, which is closed during launch and early orbit to protect the telescope optics. Twenty fours days after launch, the door will be opened to allow light to enter the telescope. The distance between the primary and secondary mirrors must be tightly controlled as it is critical to maintaining focus. Behind the telescope section, the detector module contains two independent and redundant detector systems. The beam steering mirror (BSM) mechanism, in the middle of the detector module, directs the incoming beam to one of the detector sassemblies by rotating a 45 degree mirror through an angle of 180 degrees. Between the BSM and each detector is a filter wheel mechanism, which can bring one of eleven different optical elements into the field of view.

The UVOT was the first instrument to be integrated on the Swift spacecraft at Goddard Space Flight Center, Maryland (Dec 2002)