A satellite interference location system using differential time and phase measurement techniques

1991 ◽  
Vol 6 (3) ◽  
pp. 3-7 ◽  
Author(s):  
W.W. Smith ◽  
P.G. Steffes
Keyword(s):  
Phase Measurement ◽  
Measurement Techniques ◽  
Location System

scholarly journals Single image geometry inspection using inverse endoscopic fringe projection

ACTA IMEKO ◽  
2015 ◽  
Vol 4 (2) ◽  
pp. 4 ◽  
Author(s):  
Steffen Matthias ◽  
Christoph Ohrt ◽  
Andreas Pösch ◽  
Markus Kästner ◽  
Eduard Reithmeier
Keyword(s):  
Phase Measurement ◽  
Measurement Techniques ◽  
Measuring Method ◽  
Pattern Generation ◽  
Fringe Projection ◽  
Free Form ◽  
Projection System ◽  
New Device ◽  
Early Results ◽  
Geometry Inspection

Fringe projection is an important technology for the measurement of free form elements in several application fields. It can be applied for geometry elements smaller than one millimeter. In combination with deviation analysis algorithms, errors in fabrication lines can be found promptly to minimize rejections. However, some fields cannot be covered by the classical fringe projection approach. Due to shadowing, filigree form elements on narrow or internal carrier geometries cannot be captured. To overcome this limitation, a fiberscopic micro fringe projection sensor was developed. The new device is capable of resolutions of less than 15 µm with uncertainties of about 35 µm in a workspace of 3 × 3 × 3 mm³.<br />Using standard phase measurement techniques, such as Gray-code and cos²-patterns, measurement times of over a second are too high for in-situ operation. The following work will introduce a new approach of applying a new one image measuring method to the fiberscopic system, based on inverse fringe projection. The fiberscopic fringe projection system employs a laser light source in combination with a digital micro-mirror device (DMD) to generate fringe patterns. Fiber optical image bundles (FOIB) are used in combination with gradient-index lenses to project these patterns on the specimen. This advanced optical system creates high demands on the pattern generation algorithms to generate exact inverse patterns for arbitrary CAD-modelled geometries. Approaches of the optical simulations in the context of the complex beam path, together the drawbacks of the limited resolutions of the FOIBs shall be discussed. Early results of inverse pattern simulations using a ray tracing approach of a pinhole system model are presented.<br />

scholarly journals Wavefront measurement techniques used in high power lasers

2014 ◽  
Vol 2 ◽  
Author(s):  
Haiyan Wang ◽  
Cheng Liu ◽  
Xiaoliang He ◽  
Xingchen Pan ◽  
Shenlei Zhou ◽  
...  
Keyword(s):  
High Power ◽  
Phase Measurement ◽  
Measurement Techniques ◽  
Wavefront Sensor ◽  
Power Laser ◽  
Laser Applications ◽  
High Power Lasers ◽  
Coherent Diffraction Imaging ◽  
Wavefront Measurement ◽  
Diffraction Imaging

AbstractThe properties of a series of phase measurement techniques, including interferometry, the Hartmann–Shack wavefront sensor, the knife-edge technique, and coherent diffraction imaging, are summarized and their performance in high power laser applications is compared. The advantages, disadvantages, and application ranges of each technique are discussed.

Research of Phase Measurement Techniques for Fracture Analysis of Nuclear Graphite

2018 ◽  
Vol 55 (3) ◽  
pp. 031203
Author(s):  
王琳霖 Wang Linlin ◽  
曹国强 Cao Guoqiang ◽  
王亚杰 Wang Yajie ◽  
李正强 Li Zhengqiang ◽  
王路平 Wang Luping ◽  
...  
Keyword(s):  
Phase Measurement ◽  
Measurement Techniques ◽  
Fracture Analysis ◽  
Nuclear Graphite

Interferometric phase measurement techniques for coherent beam combining

2015 ◽  
Author(s):  
Marie Antier ◽  
Jérôme Bourderionnet ◽  
Christian Larat ◽  
Eric Lallier ◽  
Jérôme Primot ◽  
...  
Keyword(s):  
Phase Measurement ◽  
Measurement Techniques ◽  
Coherent Beam ◽  
Coherent Beam Combining ◽  
Beam Combining ◽  
Interferometric Phase
Sign in / Sign up

Export Citation Format

Share Document