Title
Real-Time Spot Detection and Ordering for a Shack–Hartmann Wavefront Sensor With a Low-Cost FPGA
Abstract
A novel approach for the real-time image processing of a Shack-Hartmann wavefront sensor (SHWFS) is presented. A prevalent problem of these sensors is that during its operation highly distorted wavefronts may lead to spots that leave the confined area of the subapertures. This unnecessarily limits the dynamic range of the SHWFS. When using an SHWFS in a highly dynamic control loop, additionally, customary image processing approaches may result in large latencies, which decisively reduce the closed-loop performance. For increasing the dynamic range of an SHWFS, we employ a single-pass connected-component labeling algorithm that enables a simultaneous calculation of spots and centroids. To reduce the latency, the image processing is implemented on an FPGA in view of fully exploiting its parallelizing features. Thus, the image processing may be done in real-time with considerably lower latency than with a conventional processor. The algorithm is implemented in VHDL on a Xilinx Spartan-6. Obtained results are compared with the established approaches.
Year
DOI
Venue
2014
10.1109/TIM.2014.2310616
Instrumentation and Measurement, IEEE Transactions
Keywords
Field
DocType
computerised instrumentation,field programmable gate arrays,hardware description languages,image processing,image sensors,wavefront sensors,FPGA,SHWFS,Shack-Hartmann wavefront sensor,VHDL,Xilinx Spartan-6,centroid calculation,closed-loop performance,dynamic control loop,image processing,real-time spot detection,single-pass connected-component labeling algorithm,spot calculation,wavefront distortion,Adaptive optics (AO),FPGA,Shack--Hartmann wavefront sensor (SHWFS),Shack??Hartmann wavefront sensor (SHWFS),blob detection,connected-component labeling (CCL),dynamic range extension,wavefront sensing,wavefront sensing.
Shack–Hartmann wavefront sensor,Wavefront,Dynamic range,Computer science,Image processing,Field-programmable gate array,Electronic engineering,Control system,VHDL,Wavefront sensor
Journal
Volume
Issue
ISSN
63
10
0018-9456
Citations 
PageRank 
References 
2
0.40
3
Authors
2
Name
Order
Citations
PageRank
Steffen Mauch120.40
Johann Reger24017.29