GPI™ Family of Interferometers

ZYGO's GPI™ family of interferometers are the industry standard for noncontact measurement of flat or spherical surfaces, and transmitted wavefront measurement of optical components and assemblies. When combined with ZYGO's proprietary MetroPro® software, the GPI™ systems offer a wide range of operational features and data analysis tools for unmatched measurement capability.

The GPI™ family provides a solution for most metrology applications from the basic visual fringe inspection configuration, to a phase-modulated high-resolution measurement system, or a vibration-insensitive acquisition technique featuring ZYGO's FlashPhase™ software. Custom GPI™ solutions, for operation at a specific wavelength, or with special metrology features, are also available as part of the total metrology solution from ZYGO.

Measure glass or plastic optical components like flats, lenses, and prisms - precision metal components like computer disks, bearing and sealing surfaces - polished ceramics, and contact lens molds, too. Whatever your measurement needs, there's a GPI™ that's right for you. And, they're designed and manufactured by ZYGO; for over 30 years, our interferometers have been the metrology instruments of choice around the world.

Always the Right Choice

Each member of the GPI™ interferometer family is designed to address a specific level of measurement needs. While all GPI™ models have essentially the same purpose, they differ in operational features and data analysis capabilities.

Choosing the right GPI™ model is easy; but regardless of which system you decide on now, rest easy knowing it can be upgraded to a more advanced model, if required, in the future. The GPI's modular product structure and ZYGO's ongoing commitment to interferometry ensure that your investment is protected.

GPI™ LC - The GPI™ LC is the foundation of the GPI™ family. It allows you to perform visual fringe analysis on a high-quality 9" monochrome video monitor. The video monitor also displays ZYGO's QFAS (Quick Fringe Acquisition System) two-spot alignment. Fast and reliable electronic switching (using a hand-held remote) alternates between the "align" and "view" images on the video monitor, making fringe display a snap. Its fixed-focus optical system ensures that parts are always in focus when placed in the measurement region.

GPI™ FlashPhase™ - Take a significant step up to the GPI™ FlashPhase™ system and enjoy the benefits of a high-speed, high-resolution digital CCD camera and ZYGO's powerful MetroPro® software for data acquisition and analysis, eliminating the subjectivity of operator fringe interpretation, at a very economical price. MetroPro® provides a variety of quantitative measurement results, simultaneously, with vivid 3D rotatable color plots, sliced cross sections, and numeric displays.

The GPI™ FlashPhase™ uses unique phase-acquisition technology, which minimizes vibration sensitivity by acquiring surface information from a single frame of data. FlashPhase™ acquisition is also available for existing ZYGO and non-ZYGO interferometer systems.

The system's 6X zoom can fill the aperture with parts as small as 2/3-inch diameter, enabling you to maximize resolution for best possible measurement of your parts. And its variable focus provides a wider range of working distances by imaging the part at the camera plane, eliminating fringe distortion induced by diffraction.

GPI™ PE - The GPI™ PE represents ZYGO's newest Fizeau interferometer designed for uncompromised production metrology. A true laser Fizeau design, the GPI™ PE utilizes proprietary algorithms to ensure reliable "ripple-free" phase measurements in vibration prone environments. Compatible with all standard ZYGO accessories the GPI™ PE is the one interferometric solution that can be trusted to provide accurate surface metrology in both production and QC environments – without compromise.

• True Fizeau configuration ensures accurate metrology
• Innovative algorithms provide reliable measurements in vibration prone environments
• Easy to use production friendly GUI
• Industry preferred MetroPro® software

GPI™ XP/D - The GPI™ XP/D uses the precision of phase modulation to show fine measurement detail on your parts with excellent accuracy and repeatability. During a measurement, the interferometric cavity length is precisely modulated while a 640 x 480 CCD camera captures several fringe images, which are analyzed by MetroPro® to create a highly detailed measurement of the part being tested. For applications with parts that have large slope angles, the XP/D can be easily upgraded to include a 1k x 1k camera.

Expanded Wavelength Capabilities

Do you need a GPI™, but not at 633 nm? Perhaps you need to test in the ultraviolet range for high-precision measurements on small lenses. Maybe you need an infrared interferometer to test surfaces with large departures, or to test optics that do not transmit well in the visible range. Perhaps your optics need to be tested in transmission at the specific design wavelength. For all of these situations, and others, ZYGO's precise phase-shifting interferometer family has expanded to include several additional wavelengths. [More info...] What's more, all GPI™ systems in our expanded range are made to the same quality and reliability levels you've come to expect from ZYGO.

MetroCell™

MetroCell is a vertical measurement solution for use with ZYGO GPI™ and VeriFire™ interferometer systems. It includes an integrated vibration isolation platform and an environmentally-isolated measurement chamber. With MetroCell, there's no need to transport in-process parts to a separate test area; you have a self-contained "lab" that can be installed right on your production floor.

In addition to form characteristics of both flat and spherical components, optional accessories allow you to measure radius of curvature with unequaled precision and speed. MetroCell is available in both upward-looking and downward-looking configurations.

Flexible, Cost-Effective Configurations

All GPI™ models can be used with a three-rod mounting system. In most environments, this integrated design eliminates the need for a vibration isolation table, which saves you money and valuable floor space.

Three of the many possible configurations are shown in the illustration. Each provides a distinct advantage for the type of measurement you need to make. If you need something special, we will provide you with the components necessary to construct your own configuration, or ZYGO's Customer Service and Support department can assist you.

Every model in the GPI™ family can be used in either the horizontal or vertical configuration, and changed from one to the other at will. Use it on the production line, or in the development lab, wherever it's needed.

Custom Solutions for GPI™

Every measurement application is unique; but sometimes an application is so unique that even the highly-flexible GPI™ needs a particular configuration to handle it. This is why we developed ZYGO Custom Solutions for the GPI™. We can modify an existing system, design and build special fixturing, customize a MetroPro® software application, or engineer a completely unique system just for you. Some "typical" Custom Solutions for GPI™ are: a special wavelength, wavelength-shifting interferometers, and large vertical workstations. Just contact your local ZygoLOT sales/service office or send us a message to be on your way to a Custom GPI™ Solution.

GPI™ Accessories

A wide variety of accessories are available to expand the capabilities of the GPI™ interferometer system, allowing it to measure larger plano surfaces, and a variety of spherical surfaces. Other accessories enhance the GPI™ installation with options for vibration isolation, vertical orientation, and a beam-path switch to permit multiple simultaneous test setups. Click here for information about GPI™ accessories.

As an alternative, you can download a 10-page document (in PDF format) that describes all the GPI™ accessories. It contains the same information that is provided on the GPI™ Interferometer Accessories web pages. Just click the link below.

PDF	GPI™ Accessories (699 k)

Brochure, Specification Sheets, & Selection Guide

To download a brochure, specification sheets, or the Transmission Sphere Selection Guide for the GPI™ family of interferometers, click on the appropriate links below. The documents are in PDF format.

PDF	GPI™ LC Spec Sheet (68 k)
PDF	GPI™ FlashPhase™ Spec Sheet (188 k)
PDF	GPI™ PE Spec Sheet (72 k)
PDF	GPI™ XP/D Spec Sheet (192 k)
PDF	Transmission Sphere Selection Guide (304 k)
	Note: Adobe Acrobat Reader software is required to view and print PDF files. It is available for most computer platforms, and it's free!  You can download it now by clicking the PDF icon at left.

ZYGO's Guide to Typical Interferometer Setups

This 16-page booklet illustrates and discusses a number of the most common measurement setups for use with a ZYGO interferometer system. Download it now, or fill out a simple form to request your free copy of this informative guide!