2, 4, 6, and 8 inch Models



   Other Fizeau 

   4-inch Horizontal

   Grazing Incidence

   How Phase Works


   Graham Product Line


   Model 4VPS

   Model 6VPS

   Model 8VPS


Graham Optical Systems offers a new series of vertical Phase Interferometer configured for Plano or spherical work.  Note that for spherical work, an appropriate transmission sphere is required.

For Plano work the vertical format is usually preferred since there is no need to mount the test piece in a fixture.  The operator merely places it on the integral tip/tilt table and makes the required adjustment utilizing the Two-Spot alignment feature.  It is recommended at the time of purchase, that customer select the length of the vertical rails to accommodate the thickest test pieces to be measured . The sturdy tip/tilt table has been designed to support substantial mass.  Its height is adjustable in order to decrease the air gap between the reference surface and the test piece to minimize the effect of air currents.

Standard equipment provides remote control of  focus, zoom and intensity. In the VPS series, Durango Universal Interferometry Software interacts with Graham's EndoPhazeTM system to control Phase-Shifting.  Durango Software is installed and configured in a 2.2 GHz All-in-One Computer. 

Durango provides a wide selection of data outputs and colorful graphics and offers a live interferogram on the computer monitor so no separate video monitor is required. The operator can select the features that he wishes to display on the screen from among an assortment of graphics and data reports. Durango permits the QC manager to set the criteria for the pass/fail feature, thus permitting the routine measurement of test pieces by less skilled personnel. 

These rugged instruments are equally at home in the QC lab or in the optical fabrication shop. With excellent repeatability and reproducibility, this precision instrument provides the metrology required for all of your plano measurements.

Durango Software installed in an All-in-One Computer is provided with all Graham Phase Interferometers. 
A sample of Durango's colorful graphics  is shown atr the right.

The software also provides a Quality Control window which permits the user to enter Pass / Fail citeria.

A fitting window is available to display Zernike and Seidel coefficients.

An animated 3-D plot greatly facilitates interpretation of surface irregularities.

1/20 wave fused silica reference surface High accuracy
Rugged construction High mechanical stability
Vertical Orientation No special mount needed for test piece.
Two spot alignment For quick setup on each new part tested
Zoom Optics Standard
Adjustable height Tip/Tilt Table for thick test pieces Sturdy construction accommodates heavy test pieces
CCD Camera 768(H) x 494(V) pixels High resolution
2.2 GHz All-in-One Computer For high speed data reduction and phase shift control
Tip/Tilt plate with bayonet mount available to accommodate Transmission Flat. 1/20 wave Silica Transmission Flat Available
Interferometer can be removed from vertical rails for use in Horizontal format. Horizontal mode preferred for spherical measurements.
Reproducibility Excellent
Data reduction time  ~3 seconds (typical) Fast !
Weight Model 2VPS  60 pounds
Weight Model 4VPS 120 pounds
Weight Model 6VPS 140 pounds
Weight Model 8VPS 160 pounds
Solidly built for high stability
Manual Illustrated Operator's Manual

Graham Optical Systems,   9530 Topanga Canyon Blvd., Chatsworth,   California 91311
Phone (818) 700-1263        FAX  (818) 700-1627         E-mail:   techinfo@grahamoptical.com 
For Further Information today, call Gordon Graham today at (818) 700-1263 

Copyright © 2014 Graham Optical Systems     All Rights Reserved    Durango is a trademark of Diffraction International
This page last updated February 18, 2014