From Optical Shop Testing

Over the last 25 years, driven by both the development of new technologies such as
fast computers and solid state devices and the necessity to precisely inspect these
increasingly tiny engineering surfaces, the field of surface metrology has exploded in
both its technological sophistication and its range of application. Advances in
illumination sources, such as lasers, and in solid state detectors and optoelectronic
devices in general have fueled the development of a wide range of instruments that
can not only map surface topography but also determine other features such as
displacement or dispersion. Innovative techniques and technologies have greatly
increased the range of measurable objects, so now even difficult surfaces with high
slopes or steps and narrow, deep trenches can be measured. Many of these surface
profiling techniques were developed from distance measuring or focus detection
techniques, and they often require scanning to obtain the surface profile. This chapter
describes instruments such as the stylus profiler, scanning probe microscope, confocal
microscope and the interferometric optical profiler that are most often used to
determine surface topographies of not only very small, typically engineering
surfaces, but also smooth and large surfaces such as aspheres and glass...

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Products & Services
Optical Prisms
Optical prisms are blocks of optical material with flat, polished sides that are arranged at precisely controlled angles to one another. They are used in optical systems to deflect or redirect beams of light. They can invert or rotate images, disperse light into component wavelengths, and separate states of polarization.
Optical Lenses
Optical lenses are transparent components made from optical-quality materials and curved to converge or diverge transmitted rays from an object. These rays then form a real or virtual image of the object.  This area includes micro lenses.
Cylindrical Lenses
Cylindrical lens have at least one surface that is formed in the shape of a cylinder. Cylindrical lenses are used to correct astigmatism in the eye, and, in rangefinders, to produce astigmatism, stretching a point of light into a line.  This area includes micro cylindrical lenses as well.
Gradient Index Lenses
Gradient index (GRIN) lenses focus light through a precisely controlled radial variation of the lens material's index of refraction from the optical axis to the edge of the lens.

Topics of Interest

This chapter discusses moire, fringe projection, structured illumination, holographic interferometry, digital holography, and speckle interferometry techniques for testing diffuse surfaces. Diffuse...

The chromatic confocal measuring technique uses a white light source. The white light is delivered from the control unit to the probe via an optical fibre. With no moving parts or electronics, the...

4.0 MICROSCOPY This section discusses both optical and electron microscopes. Both microscopes have their particular limitations and advantages. While there are a wide variety of optical microscopes,...

Chapter List Chapter 13: Optical Microscopy Chapter 14: Wide-Field Autofluorescence Microscopy for the Imaging of Living Cells Chapter 15: Scanning Probe Microscopy Chapter 16: Confocal and...

Three-dimensional imaging interferometric microscopes have outstanding accuracy, provided of course that the test objects are sufficiently smooth and continuous. The present study shows that a...