AMETEK, Inc. Logo
Products 3D Optical Profilers Laser Interferometers Position Metrology Systems Custom Metrology Solutions Trade-in & Upgrade Program

Laser Interferometers Verifire™ Verifire™ HD Verifire™ HDX  New! DynaFiz® Interferometer Accessories

Special Applications Verifire™ MST Verifire™ XL Large Aperture Systems UV and IR Interferometers Upgrades

Verifire™ MST Interferometer System for Multiple Surface Testing

Verifire MST Interferometer System
Verifire™ MST laser interferometer enables precise optical metrology of multiple surfaces simultaneously, including plane parallel components with multiple reflections.

The Verifire™ MST starts with the classical interferometer applications. These applications all measure the wavefront variations between two surfaces, a two-surface cavity. However, measuring an uncoated parallel plate gives two layered interferograms (a three-surface cavity) that confuse standard Phase Shift Interferometry algorithms.

ZYGO has solved this problem using wavelength shifting of phase, and ZYGO's patented Fourier Transform Phase Shifting Interferometry (FTPSI). The Verifire™ MST can measure two-surface, three- and even four-surface cavities. Show all of the surfaces, or only the surfaces of interest, all within ZYGO's Mx™ software. Artifacts are naturally suppressed using FTPSI, eliminating the need for an extended source.

Key Features:

• Simultaneously measures two-surface, three- and even four-surface cavities.

• Measures front surface map, optical thickness variation, and the back surface approximation.

• Available in: 633 nm, 1.053 µm, 1.064 µm, and 1.55 µm wavelengths.

• Greatly simplifies homogeneity metrology.

Verifire MST Multi Surface Test Measurement Maps

Measuring Thin Optics

The Verifire™ MST system is able to reliably measure glass thinner than 1 mm.

Thin glass is very susceptible to environmental influences, so even small changes in vibration or air turbulence can adversely affect the data. Therefore it is very advantageous to be able to measure the front and back surfaces simultaneously. If the surfaces were measured separately, the environment could change between measurements, and there would be no way to correct for it.

The measurability of thin glass is determined by its optical thickness, which is affected by the material of which it is made. Optical thickness is calculated as the physical thickness multiplied by the index of refraction. Therefore, parts with a higher index can be physically thinner and still be measured by the Verifire MST system.

Near IR and Short-Wave IR Testing

Testing at an optical system's design wavelength is critical for final alignment and qualification. Night vision, IR and thermal imaging systems for aerospace and defense, lithography subsystems, remote sensing telescopes, and exotic material qualification all require testing at design wavelength.

To meet this need, the Verifire™ MST interferometer system is available at 1.053 µm, 1.064 µm, and 1.55 µm wavelengths, in addition to the 633 nm model. This allows for measurements of homogeneity and TTV (total thickness variation) of materials that are not transmissive in the visible spectrum, such as Silicon. It also allows for testing at the operating wavelength for optics used in high-energy laser and free-space communication applications.

Optical Homogeneity and Total Thickness Variation

An important property of an optical component is the homogeneity of the refractive index of the material from which it is made. Variations in the material's refractive index will affect the wavefront passing through it, thus affecting the performance of the optic in critical applications. Similarly, variations in the thickness of the optic changes the length of the optical path which, affects the wavefront passing through it.

The capability to measure optical homogeneity and total thickness variation (TTV) is a standard feature of the Verifire™ MST system. A simple, two-measurement process is all it takes. The traditional methods of using oil-on plates, or requiring the optic to have a degree of wedge, are no longer necessary.

Measurement calculations are accomplished with sophisticated proprietary software algorithms, developed by ZYGO engineers and implemented in the Mx™ software package. The algorithms accurately differentiate between all four surfaces in the cavity to provide simultaneous measurements of the optic's front and back surfaces, physical and optical thickness variation, nonlinear homogeneity, and linear homogeneity.

Inquiry Form
Please use the form below to contact us with any questions you have regarding ZYGO's Verifire MST interferometer system, or interferometry in general.

First Name * Last Name *
Phone Number E-mail Address *
Company or Organization * Job Title or Function *
Street Address City
State/Province * Zip/Postal Code
Country/Region *
  Check this box to provide consent for ZYGO to contact you in the future. **
Please indicate your level of interest... *
 Current Need      Upcoming Need      Possible Need      Gathering Data
Please type your inquiry below:
* Required entries  

If you experience any difficulty submitting this form, contact:

** You may withdraw this consent at any time using the "unsubscribe" link at the bottom of any page on this web site.

By continuing to use this site, you agree to our Privacy and Cookie Policy. OK

Brochures Application Notes Manuals Technical Papers

Note: Login Required to download Application Notes; Click for details.

Contact ZYGO Today

Social Media Icons LinkedIn Twitter Facebook Google+ YouTube
  Privacy and Cookie Policy        Privacy Policy Inquiry Form        Unsubscribe
× Enter the email address you would like to unsubscribe from future contact...


Or, if you have a question, please use our Privacy Policy Inquiry form.