Zero Length Viewport, Fused Quartz, 2.69 Inch Clear Aperture, CF 4.5 Inch, 304 Stainless Steel Flange, Pfeiffer

Zero length ConFlat (CF) viewports are used for light transmission in ultra-high vacuum applications. The front face of the window sits flush or just below the flange, introducing zero additional length beyond the typical thickness of a conflat flange. The window is brazed or fused to a thin, folded metal ring. The brazed connection is compatible with ultra-high vacuum and the folded metal ring introduces enough flexibility that the windows do not crack during dissimilar thermal expansion between the window and flange. The brazed connection between window and metal allows these viewports to handle higher bakeout temperatures than viewports that contain O-rings. The outer conflat flange uses a copper gasket and knife-edges to achieve a high vacuum seal and can operate down to 10^-13 torr.

Fused quartz is a high quality optics material used in a wide range of optical applications. It is highly transparent in the ultraviolet (UV), visible, and near infrared (NIR) regions, has high strength and scratch resistance, and resists most chemicals. Fused quartz typically has improved transparency in the NIR region and reduced transparency in the UV compared to fused silica.

This viewport is from Pfeiffer Vacuum.