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Image Processing|4 Article(s)
Experimental investigation of ghost imaging of reflective objects with different surface roughness
Suqin Nan, Yanfeng Bai, Xiaohui Shi, Qian Shen, Lijie Qu, Hengxing Li, and Xiquan Fu
We present an experimental demonstration of ghost imaging of reflective objects with different surface roughness. The influence of the surface roughness, the transverse size of the test detector, and the reflective angle on the signal-to-noise ratio (SNR) is analyzed by measuring the second-order correlation of the light field based on classical statistical optics. It is shown that the SNR decreases with an increment of the surface roughness and the detector’s transverse size or a decrease of the reflective angle. Additionally, the comparative studies between the rough object and the smooth one under the same conditions are also discussed. We present an experimental demonstration of ghost imaging of reflective objects with different surface roughness. The influence of the surface roughness, the transverse size of the test detector, and the reflective angle on the signal-to-noise ratio (SNR) is analyzed by measuring the second-order correlation of the light field based on classical statistical optics. It is shown that the SNR decreases with an increment of the surface roughness and the detector’s transverse size or a decrease of the reflective angle. Additionally, the comparative studies between the rough object and the smooth one under the same conditions are also discussed.
Photonics Research
- Publication Date: Jul. 26, 2017
- Vol. 5, Issue 4, 04000372 (2017)
High-resolution pseudo-inverse ghost imaging
Wenlin Gong
We present a pseudo-inverse ghost imaging (PGI) technique which can dramatically enhance the spatial transverse resolution of pseudo-thermal ghost imaging (GI). In comparison with conventional GI, PGI can break the limitation on the imaging resolution imposed by the speckle’s transverse size on the object plane and also enables the reconstruction of an N-pixel image from much less than N measurements. This feature also allows high-resolution imaging of gray-scale objects. Experimental and numerical data assessing the performance of the technique are presented. We present a pseudo-inverse ghost imaging (PGI) technique which can dramatically enhance the spatial transverse resolution of pseudo-thermal ghost imaging (GI). In comparison with conventional GI, PGI can break the limitation on the imaging resolution imposed by the speckle’s transverse size on the object plane and also enables the reconstruction of an N-pixel image from much less than N measurements. This feature also allows high-resolution imaging of gray-scale objects. Experimental and numerical data assessing the performance of the technique are presented.
Photonics Research
- Publication Date: Aug. 21, 2015
- Vol. 3, Issue 5, 05000234 (2015)
Enhanced depth resolution in optical scanning holography using a configurable pupil
Haiyan Ou, Ting-Chung Poon, Kenneth K. Y. Wong, and and Edmund Y. Lam
The optical scanning holography (OSH) technique can capture all the three-dimensional volume information of an object in a hologram via a single raster scan. The digital hologram can then be processed to reconstruct individual sectional images of the object. In this paper, we present a scheme to reconstruct sectional images in OSH with enhanced depth resolution, where a spatial light modulator (SLM) is adopted as a configurable point pupil. By switching the SLM between two states, different Fresnel zone plates (FZPs) are generated based on the same optical system. With extra information provided by different FZPs, a depth resolution at 0.7 μm can be achieved. The optical scanning holography (OSH) technique can capture all the three-dimensional volume information of an object in a hologram via a single raster scan. The digital hologram can then be processed to reconstruct individual sectional images of the object. In this paper, we present a scheme to reconstruct sectional images in OSH with enhanced depth resolution, where a spatial light modulator (SLM) is adopted as a configurable point pupil. By switching the SLM between two states, different Fresnel zone plates (FZPs) are generated based on the same optical system. With extra information provided by different FZPs, a depth resolution at 0.7 μm can be achieved.
Photonics Research
- Publication Date: Nov. 05, 2014
- Vol. 2, Issue 2, 02000064 (2014)
Method for enhancing visibility of hazy images based on polarimetric imaging
Jian Liang, Liyong Ren, Enshi Qu, Bingliang Hu, and Yingli Wang
A novel polarimetric dehazing method is proposed based on three linear polarization images (0°, 45°, and 90°). The polarization orientation angle of the light scattered by the haze particles is introduced in the algorithm. No additional image-processing algorithm is needed in the postprocessing. It is found that the dehazed image suffers from little noise and the details of the objects close to the observer can be preserved well. In addition, this algorithm is also proved to be useful for preserving image colors. Experimental results demonstrate that such an algorithm has some universality in handling all kinds of haze. We think that this robust algorithm might be very suitable for real-time dehazing. A novel polarimetric dehazing method is proposed based on three linear polarization images (0°, 45°, and 90°). The polarization orientation angle of the light scattered by the haze particles is introduced in the algorithm. No additional image-processing algorithm is needed in the postprocessing. It is found that the dehazed image suffers from little noise and the details of the objects close to the observer can be preserved well. In addition, this algorithm is also proved to be useful for preserving image colors. Experimental results demonstrate that such an algorithm has some universality in handling all kinds of haze. We think that this robust algorithm might be very suitable for real-time dehazing.
Photonics Research
- Publication Date: Mar. 03, 2014
- Vol. 2, Issue 1, 01000038 (2014)
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