The Verifire™ MST interferometer system from ZYGO is designed for multiple surface testing, and the system provides unmatched results and measurement capabilities. It starts with classical interferometer applications; all of these applications measure the wavefront variations between two surfaces, a two-surface cavity.
However, when an uncoated parallel plate is measured, it provides two layered interferograms (a three-surface cavity) that only confuse standard Phase Shift Interferometry algorithms.
ZYGO has resolved this issue by using wavelength shifting of phase and the company’s patented Fourier Transform Phase Shifting Interferometry (FTPSI). The Verifire™ MST can measure two-, three- and even four-surface cavities. It reveals all of the surfaces, or only the surfaces of interest, within MetroPro® software. FTPSI is used to suppress the artifacts naturally, which removes the need for an extended source.
The key features of the Verifire™ MST interferometer system are as follows:
- Significantly simplifies homogeneity metrology
- Capable of measuring two-surface, three-surface and even four-surface cavities simultaneously
- Measures optical thickness variation, front surface map, and the back surface approximation