Tag Archives: interferometry

Improving Surface Measurements by Interferometers

The basic principles of interferometry date back to the seventeenth century. Interferometry uses the characteristics of electromagnetic waves to gather information about a sample. Interferometers have been employed to measure radiation from bodies in outer space as part of astronomical research. In the context of nanotechnology research, optical interferometers use light to gather information about the surface and … Continue reading

November 4, 2021 Blog, Herzan, Optomechanics

Measurements with a Laser Interferometer Made Easy!

To measure prisms and substrates with a laser interferometer, you are typically forced to paint or tape surfaces. Time is wasted, parts damaged, and accuracy degraded. Spectrally Controlled Interferometry (SCI) directly measures these parts down to 150 µm OPL ((or even 75 µm on special request). No taping, no painting…just measure. SCI is simply faster and more … Continue reading

April 28, 2021 Apre Instruments, Blog, Interferometers, Systems

Measuring Radius of Curvature of Optical Surfaces

An essay from Apre Instruments describes the multiple methods used today to measure an optical surface radius: Test plates Mechanical probe Interferometer “Cateye to Confocal” The essay then discusses the benefits of Apre’s Spectrally Controlled Interferometry (SCI) measurement method, including: Easy alignment in laser mode Electronically switch to white light mode to isolate fringes to … Continue reading

November 4, 2020 Apre Instruments, Blog, Interferometers, Systems

Measuring Material Homogeneity with SCI

Optical index homogeneity is an important material parameter influencing lens performance. Laser interferometers have painstakingly measured this parameter which requires four separate measurements.  Laser interferometers have either required the use of contact plates with oft times poisonous index matching fluids or polishing a wedge into the test part to isolate the front from the back … Continue reading

October 28, 2020 Apre Instruments, Blog, Interferometers, Systems

Massive Gravitational Wave Binary Discovered with Laser Interferometer

“On September 2nd the LIGO Scientific Collaboration and the Virgo Collaboration announced the discovery of GW190521. T, the most massive gravitational wave binary observed to date.” This was the statement released to the press by the scientific institutions, regarding a May 21st 2019 recorded event. This ripple across space-time has propagated for more than 7-billion … Continue reading

September 29, 2020 Access Laser, Blog, Lasers

SCI Measures Optical Domes Faster and More Accurately

Dome optics are the last component in a growing number of imaging and guidance applications. Domes protect the imaging optics from the surrounding environment without degrading optical performance. Therefore the dome’s transmitted wavefront quality is important to control since it directly influences the final image quality. Dome applications include: Underwater cameras Submersibles for robotic and manned … Continue reading

October 24, 2019 Apre Instruments, Blog, Interferometers, Systems