2, 4, and 6 inch Models


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Graham Optical Systems offers a new series of vertical Phase Interferometer configured for Plano work.  The 1/20 wave reference surface is included and forms an integral part of the collimator, thus eliminating the need to purchase a separate transmission flat.

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 focus, zoom and intensity controls directly on the instrument body.  A remote control option is offered. In the VPS series, Durango Universal Interferometry Software interacts with Graham's EndoPhazeTM system to control Phase-Shifting.  The software, Image Acquisition Board, and Data Acquisition Board are installed in a 3 GHz computer.  A 22-inch TFT flat screen monitor is included.  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

2-inch aperture (50.8 mm )
4-inch aperture (101.6 mm)
6-inch aperture (152.4 mm)
Select the Model that best suits your purpose 
1/20 wave fused silica reference surface High accuracy
Proprietary Optics for superior performance Highest contrast and cleanest interferogram of any interferometer available today.  No bull's-eye aliases!
Rugged construction High mechanical stability
A Turnkey System User Friendly and ready to go
Vertical Orientation No special mount needed for test piece.
Your choice of rail length Select from 24, 30, 36, 42, or 48 inch rails at purchase
Two spot alignment For quick setup on each new part tested
Single Mode Diode Laser source (635 nm) Dithered for Sharp, speckle-free images
Zoom Optics Standard
Zoom, Focus, Iris, Intensity and Remote Control Standard 
Adjustable height Tip/Tilt Table for thick test pieces Sturdy construction accommodates heavy test pieces
EndoPhazeTM for hysteresis-free phase shifting For extra accuracy, repeatability and reproducibility!
CCD Camera 768(H) x 494(V) pixels High resolution
Durango Universal Interferometry Software* Windows environment
PV and rms in users choice of units
High level of repeatability
Excellent reproducibility
Large choice of graphic displays
Dynamic Sections
3-D OPD Plot
Reference Subtraction
MTF and PSF graphics and plots
Zernike Polynomials available for all measurements
Seidel Coefficients available
Pass/Fail Feature
Selection of colorful, printable reports
3.02 GHz computer with INTEL® Core™ i-3 540 processor For high speed data reduction and phase shift control
22-inch TFT Flat Screen Monitor For easy viewing
Live interferogram on computer monitor For quick inspection without extra video monitor
Reference surface is an integral part of the interferometer and always aligned to collimated beam. No need to purchase a separate Transmission Fat.
No need to adjust Tip/Tilt of a Transmission Flat
High Accuracy  1/20 wave (uncalibrated) 
1/300 wave (calibrated)
Repeatability 1/100 wave PV   1/1000 wave rms
Reproducibility Excellent
Data Acquisition time 30 milliseconds (typical) Fast
Data reduction time  ~3 seconds (typical) Fast
Footprint Model 2VPS (W x D) 12 x 12 inches
Footprint Model 4VPS (W x D) 18 x 20 inches
Footprint Model 6VPS (W x D) 20 x 24 inches
Small footprint -- you choose the height!
Weight Model 2VPS   75 pounds
Weight Model 4VPS 120 pounds
Weight Model 6VPS 140 pounds
Solidly built for high stability
Power 117 V 60 Hz 2 A (or 240 V 50 Hz 2A) Wired with plug to suit the customer's power source
Manual Illustrated Operator's Manual
Warranty Standard one-year limited warranty against defective components or workmanship. Extended warranty available.
Graham Optical Systems, 9530 Topanga Canyon Blvd., Chatsworth, California 91311     
For Further Information today, call Gordon Graham today at (818) 700-1263  E-mail: techinfo@grahamoptical.com 
Copyright © 2011 Graham Optical Systems  All Rights Reserved   * Durango is a trademark of Diffraction International
EndoPhazeTM is a trademark of Graham Optical Systems

 This page last updated November 25, 2011