Viewports (at Room Temperature)

Related subgroups: MIR, IOO, MIF, VAC, CRY, VIS...

Scope

This subsystem provides the optical viewports to pass through the optical beams from the vacuum chambers in which LCGT main interferometer is stored. The optical beams include...

The viewport subsystems that will be applied to the cryo-vacuum chambers for ITMs/ETMs of the future LCGT are NOT included in the scope of this subsystem so far.

Applicable Documents

• Spec. for vacuum chambers
• Optical Layout Drawing of the LCGT interferometer
• Length Sensing doc
• Alignment Sensing doc
• Optical lever doc
• CCD Monitor doc
• Any...

General Description

We can extract optical beams at the viewports from the interferometer inside the vacuum chamber. The optical beams are for length control scheme of the interferometer, alignment control scheme of the mirrors, optical levers for LCGT-SUS, and other monitoring devices (CCD or equivalent video cameras).

Damping stray lights?

• AR coating for 1064 nm and 532 nm
• Wedge angle

Details are described in Characteristics section.

Functions

• Optical Lever
• Video camera
• Illumination
• Diagnostic
• Squeeze
• (Spare)

Naming Conventions

Locations

• BS chamber

Requirements

Characteristics

Inspection plans

Links

• LIGO-T1000746-v1, Viewports Subsystem Final Design Document

• LIGO-T1000022-v4, Viewports Subsystem Requirements Document

• LIGO-T1000334-v1, Review Report Interferometer Sensing and Control Final Design