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GC1TP Glass Threaded Optical Port with KF25100C Flange to Compression Fitting Adapter and GC1 End Cap Holding a WG31050-D Sapphire Window

Features

• 60 mm Long Glass Port for Coupling beams into and out of Vacuum Systems
• Ø20 mm Clear Aperture through the Length of the Port
• One End Features  Ø28 mm GL-32 Threading Allowing Installation of Interchangeable Ø1" Windows
• Compatible with KF25C100 Flange to Compression Fitting Adapter for Ø1" or Ø25 mm Pipes
• Suitable for Use at Pressures from 10^-7 Torr to 5 psi at 25°C
• Custom Design and Manufacturing Services Available (Contact Tech Support)

Thorlabs' GC1TP Glass Threaded Optical Port provides a solution for coupling beams into or observing processes inside of a vacuum chamber. The GC1TP threaded optical port features one end with an external Ø28 mm GL-32 glass threading, which allows users to secure Ø1" flat or wedged windows (3 - 5 mm thick) using a GC1 Threaded End Cap. The other end has an OD of Ø1" and is compatible with the KF25C100 Flange to Compression Fitting Adapter for Ø1" or Ø25 mm pipes. A glass rib, made from heating the ports and pushing them onto themselves, circles the ports and ensures that there is no movement under vacuum when the ports are installed in compression fittings. See the Application tab for instructions on creating a vacuum seal with a KF flange. 

The overall length of the port is 60 mm for ease when installing/uninstalling the compression fitting as well as allowing the GC1 cap to thread fully on the port. The clear aperture of Ø20 mm is maintained with the GC1 end cap attached for optimal optical access through the port.

The GC1TP threaded optical port is made from borosilicate glass, a rugged material known to resist chipping and cracking, and has high transmission from 350 nm to 2200 nm. It can hold a vacuum below 10^-7 Torr and withstand pressures up to 5 psi when properly assembled. The post-production cleaning process consists of an ultrasonic cleaning followed by a methanol rinse. The port is then connected to a vacuum system and leak tested. The port is not vacuum sealed when shipped; before using the port in a vacuum setup, we advise users to follow a similar cleaning process.

Creating a Vacuum Seal with a KF Flange

Thorlabs' KF25C100 can be used to manage gas flow in and out of the optical port. Thorlabs' GC1TP Glass Threaded Optical Port is terminated on one end with a Ø1" tube that can be inserted into the KF25C100 flange-to-compression-fitting adapter.

To input the glass cell into a KF25 vacuum system, follow the instructions below.

1. Coat a cleaned and inspected KF25CR-F Centering O-Ring in vacuum grease and place it on a base post or pipe.
2. Place the KF25C100 flange-to-compression-fitting adapter on top of the KF25CR-F Centering O-Ring and secure them with the KF25WNC wing nut clamp.
3. Loosen and remove the knurled locking knob, O-ring, and seal sing of the flange-to-compression-fitting adapter so its mating surface can be inspected and the included O-ring can be coated in vacuum grease. This will create a vacuum seal when the cell is inserted into the system.
4. Slide the Ø1" tube end of the glass optical port through the top (side with the Thorlabs engraving) of the knurled locking knob, seal ring (with the counterbore seat for the O-ring facing the adapter body), and O-ring (in that order) of the flange-to-compression-fitting adapter.
5. Slide the glass tube into the flange adapter body and then slide the O-ring, seal ring, and knurled locking knob down the tube onto the flange adapter body. Tighten the knurled locking knob by hand.

It is not recommended to insert the glass tube into a fully assembled KF Flange-to-compression-fitting adapter. The sharp edges of the glass tube may damage the O-ring thus causing the seal to fail.