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Journal ArticleDOI

High dynamic range scanning technique

01 Mar 2009-Optical Engineering (International Society for Optics and Photonics)-Vol. 48, Iss: 3, pp 033604
TL;DR: This paper addresses a high dynamic range scanning technique that can measure this type of object by taking advantage of one merit of a phase-shifting algorithm: pixel-by-pixel phase retrieval.
Abstract: Measuring objects with a high variation range of surface reflectivity is challenging for any optical method: This paper addresses a high dynamic range scanning technique that can measure this type of object. It takes advantage of one merit of a phase-shifting algorithm: pixel-by-pixel phase retrieval. For each measurement, a sequence of fringe images with different exposures are taken: the brightest ones have good fringe quality in the darkest areas while the darkest ones have good fringe quality in the brightest areas. They are arranged from brighter to darker (i.e., from higher exposure to lower exposure). The final fringe images, used for phase retrieval, are produced pixel-by-pixel by choosing the brightest but unsaturated corresponding pixel from one exposure. A phase-shifting algorithm is employed to compute the phase, which can be further converted to coordinates. Our experiments demonstrate that the proposed technique can successfully measure objects with high dynamic range of surface reflectivity variation.
Citations
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Journal ArticleDOI
Song Zhang1
TL;DR: The principles of the real-time 3D shape measurement techniques that were developed are presented, the most recent progresses that have been made in this field are summarized, and the challenges for advancing this technology further are discussed.

926 citations


Cites background from "High dynamic range scanning techniq..."

  • ...Zhang and Yau proposed a technique, that is called high dynamic range scanning technique, to deal with this time of objects [62]....

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Journal ArticleDOI
TL;DR: An overview of state-of-the-art phase shifting algorithms for implementing 3D surface profilometry is presented to provide a useful guide to the selection of the most appropriate phase shifting technique for a particular application.

611 citations

Journal ArticleDOI
TL;DR: An overview of these state-of-the-art MFPP works is presented by analyzing and comparing the measurement principles, systems structures, and key performance indexes such as the accuracy, field of view (FOV), and speed.

158 citations

Journal ArticleDOI
TL;DR: Wang et al. as mentioned in this paper presented a novel 3D scanning technique for high-reflective surfaces based on phase-shifting fringe projection method, which is developed to process the fringe images reflected from the shiny surfaces, and generates a synthetic fringe image by fusing the raw fringe patterns, acquired with different camera exposure time and the illumination fringe intensity from the projector.

136 citations

Journal ArticleDOI
TL;DR: Experimental results show that the first technique can effectively improve the measurement accuracy of diffuse objects with LRR, the second one is capable of measuring object with weak specular reflection (WSR: e.g. shiny plastic surface) and the third can inspect surface with strong specular reflections precisely.

128 citations

References
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BookDOI
TL;DR: In this paper, a completely rewritten chapter was added to cover wavefront fitting and evaluation as well as holographic and Moire methods, and an appendix was added suggesting appropriate tests for typical optical surfaces.
Abstract: Fringe scanning techniques, now renamed heterodyning or phase shift interferometry, are covered in a completely rewritten chapter. New chapters have been added to cover wavefront fitting and evaluation as well as holographic and Moire methods. The chapter on parameter measurements has been completely rewritten and an appendix added suggesting appropriate tests for typical optical surfaces.

2,372 citations

Journal ArticleDOI
TL;DR: A novel systematic method is proposed for accurate and quick calibration of a 3-D shape measurement system based on a structured light technique to enable the projector to "capture" images like a camera, thus making the calibration ofA projector the same as that of a camera.
Abstract: System calibration, which usually involves complicated and time-consuming procedures, is crucial for any 3-D shape measurement system. In this work, a novel systematic method is proposed for accurate and quick calibration of a 3-D shape measurement system we developed based on a structured light technique. The key concept is to enable the projector to "capture" images like a camera, thus making the calibration of a projector the same as that of a camera. With this new concept, the calibration of structured light systems becomes essentially the same as the calibration of traditional stereovision systems, which is well estab- lished. The calibration method is fast, robust, and accurate. It signifi- cantly simplifies the calibration and recalibration procedures of struc- tured light systems. This work describes the principle of the proposed method and presents some experimental results that demonstrate its performance. © 2006 Society of Photo-Optical Instrumentation Engineers.

687 citations

Journal ArticleDOI
TL;DR: A multilevel quality-guided phase unwrapping algorithm for real-time 3D shape measurement is presented and it is demonstrated that this algorithm improves the previous scan-line phase unwrap algorithm significantly although it reduces its processing speed slightly.
Abstract: A multilevel quality-guided phase unwrapping algorithm for real-time 3D shape measurement is presented. The quality map is generated from the gradient of the phase map. Multilevel thresholds are used to unwrap the phase level by level. Within the data points in each level, a fast scan-line algorithm is employed. The processing time of this algorithm is approximately 18.3 ms for an image size of 640x480 pixels in an ordinary computer. We demonstrate that this algorithm can be implemented into our real-time 3D shape measurement system for real-time 3D reconstruction. Experiments show that this algorithm improves the previous scan-line phase unwrapping algorithm significantly although it reduces its processing speed slightly.

201 citations

Proceedings ArticleDOI
07 Nov 2005
TL;DR: A new method to totally eliminate double bounced light is presented, which is more efficient than the traditional solution that uses polarizers and multiple cameras are used to measure different areas.
Abstract: In manufacturing, inspection and measurement systems have long been desired to be able to measure as many kinds of parts as possible without treating the surface. Specifically, measuring shiny parts has been a big challenge for optical metrology because of double-bounced light -- a phenomenon that light can be reflected from an area to another on the surface. The unwanted light will result in higher noise and can even make the measured results unacceptable. Traditionally, a polarizer is placed in front of both the light sources and the camera. After properly adjusting the polarizer in front of the camera, the double bounced reflected light can be blocked to some degree while the normally reflected light can go through. By this way, the extra reflections can be reduced but not totally eliminated. This paper presents a new method to totally eliminate double bounced light. Here, color light sources are used to illuminate the part and multiple cameras are used to measure different areas. Each camera views through an appropriate color filter so that only a certain color light is seen. The measured results from all cameras are then merged together to create the complete image. This method is more efficient than the traditional solution that uses polarizers. Both measurement principle and some results are given.

47 citations