Test & Measurement Articles

Except for direct illumination from the sun, laser, or other light source, everything we see or detect is ultimately scattered light. Light can be scattered or rescattered during its propagation to...

When evaluating the surface of a component, surface roughness can be assessed by eye or by rubbing it with a fingertip. Common expressions include “shiny,” “lusterless and...

Given the pace at which technology advances, there always seems to be a learning curve. With the abundance of consumer electronics available, there typically is no right or wrong way to use these...

An interferometer is an instrument that compares the position or surface structure of two objects. The basic two-beam division of amplitude interferometer components consists of a light source, a...

All optical spectrometry techniques rely on the measurement of radiant power. The configuration of the instrument varies based on the measurement technique: absorption, emission, luminescence, or...

Measuring pulsed-beam lasers has generally required the use of a CCD array profiler. This is a reasonable solution for low-power lasers in the UV and visible wavelength range, but these require...

Conditions on the factory floor and in industrial cleanrooms with high-capacity air filtration systems can hamper the use of interferometry. Another problem is the testing of large-aperture mirrors...

Particle image velocimetry (PIV) is an experimental tool in fluid mechanics and aerodynamics. The basic principle involves photographic recording of the motion of microscopic particles that follow...