"; _cf_contextpath=""; _cf_ajaxscriptsrc="/cfthorscripts/ajax"; _cf_jsonprefix='//'; _cf_websocket_port=8578; _cf_flash_policy_port=1244; _cf_clientid='81D815BF82896FE480B128A0ED78E8A3';/* ]]> */
| ||||||||||||||||||||||||||||||||||||||||||||
High-Vacuum CF Flange Viewports for Ø1" Windows![]()
VC224 Ø1" Flat Window Viewport, Front VGA10 Annealed Copper Gaskets, Back VMH6 Flange Mounting Hardware Pack VC22VO Viton O-Ring ![]() Please Wait
Features
Thorlabs' high-vacuum-compatible Ø2.75" (DN40) CF Flange Viewports for Ø1" Optics are offered with one of three uncoated window substrates: sapphire (150 nm - 4.5 µm), CaF2 (180 nm - 8.0 µm), or UVFS (185 nm - 2.1 µm). Please see the Graphs tab for transmission data. Additionally these viewports are compatible with our selection of stock Ø1" windows with thicknesses between 4.9 - 5.15 mm. These flanges are not compatible with wedged windows. Designed for use at high-vacuum (HV) pressures, Thorlabs' CF viewports utilize Viton O-Ring seals to create an air-tight metal/glass seal, allowing for pressures down to 10-8 Torr. The vacuum windows are interchangeable, enabling the user to swap out vacuum windows mounted in our HV CF flanges. Additionally, CF flanges (viewports without vacuum windows) are also available that are also compatible with our Ø1" windows. Before swapping and attempting to install additional windows, please review the procedure outlined in the Window Installation tab above. Copper gasket and mounting hardware sets for Ø2.75" CF flanges are also available below. Thorlabs also offers HV CF Flange Viewports for Ø1.5" windows and Ø1.5" wedged windows.
The graphs below show the transmission of light through uncoated sapphire, calcium fluoride (CaF2), and UV fused silica substrates. Raw data in the Excel format is available by clicking on the links below the graphs. ![]() Click to Enlarge Fig. 5: Order of faceplate screw tightening. ![]() Click to Enlarge Fig. 4: Viewport with faceplate aligned over screw holes. ![]() Click to Enlarge Fig. 3: Viewport with top O-ring placed on window. ![]() Click to Enlarge Fig. 2: Viewport with window placed on bottom O-ring. ![]() Click to Enlarge Fig. 1: Viewport with front face removed and O-ring inserted. Our high-vacuum viewports allow the user to install or swap out windows as they desire, or as experimental conditions demand. Installation of the windows is relatively quick and simple. The following steps describe how to install and change windows in our high-vacuum CF flanges. Step 1: Inspect the O-ring and seat for pits, scratches, or contamination. Remove any loose debris from the seat using compressed air and then install the O-ring in the seat (see Fig. 1). If necessary, clean the window by following our optics cleaning tutorial. Step 2: Place the window on top of the O-ring (see Fig. 2) and then place and center the second O-ring on top of the window (see Fig. 3). Step 3: Set the faceplate on top of the window, lining up the O-ring with the faceplate groove and the six holes in the faceplate with the threaded holes in the flange (see Fig. 4). Do not slide the part across the window surface. Step 4: Place the six screws in the faceplate holes and use a 5/64" (2.0 mm) hex key to thread them so that they are just making contact with the faceplate. Step 5: In the order illustrated in Fig. 5, turn each screw a quarter turn, repeating the pattern until the faceplate is tight against the flange.
![]() ![]() Click for Details Mechanical Drawing of VC22 Series Flanges
Thorlabs' Ø2.75" CF flange viewports allow for optical access into high-vacuum (HV) systems down to 10-8 Torr. These are fixed (non-rotating) flanges with Ø1" windows that provide a Ø0.71" (Ø18 mm) clear aperture (CA). Note that the CA is limited by the optic rather than the flange's internal diameter. These viewports have six 1/4" (M6) through holes for bolting onto any standard Ø2.75" CF flange. Please note that mounting hardware is not included. Our HV CF viewports can be purchased with one of three uncoated windows: sapphire, CaF2, or UVFS. Additionally, the provided window may be replaced with any of our Ø1" windows that are 4.9 - 5.15 mm thick. ![]()
Thorlabs' Ø2.75" CF flange does not include a window but is compatible with any Thorlabs Ø1" window that is 4.9 to 5.15 mm thick. When combined with the appropriate window, this flange allows for optical access into high-vacuum (HV) systems down to 10-8 Torr. This fixed (non-rotating) flange has six 1/4" (M6) through holes for bolting onto any standard Ø2.75" CF flange. Please note that mounting hardware is not included. The CF-style flange utilizes a knife-edge mechanism to create an airtight seal between mating pieces. To create the seal, a copper gasket (available below) is most often employed. As the bolts of the mating pair are tightened, the knife edge "bites" into the copper gasket, deforming it. The extruded metal fills any machining marks or surface defects, yielding a leak-tight seal. ![]()
Thorlabs offers mounting hardware and single-use copper gaskets for mating Ø2.75" CF flanges. These flanges utilize a knife-edge mechanism to create an airtight seal between mating pieces. To create the seal, a copper gasket is most often employed. As the bolts of the mating pair are tightened, the knife edge bites into the copper gasket, deforming it. The extruded metal fills all the machining marks and surface defects, which yields a leak-tight seal. 1/4-hard and annealed copper gaskets are sold in sets of 10. We recommend the 1/4-hard copper gaskets for most applications; for more delicate devices, such as viewports, we recommend using the softer annealed copper gaskets to lower the chance of deformation in the optic due to stress in the flange. The set of stainless steel mounting hardware includes six silver-plated bolts, six nuts, and twelve washers. The silver plating on the bolts acts as a lubricant to prevent galling between the stainless steel surfaces of the bolt and the nut. Instructions | ||||||||||||||||||||||||||||||||||||||||||||
|