Endoscopy 2018; 50(04): S133
DOI: 10.1055/s-0038-1637428
ESGE Days 2018 ePoster Podium presentations
21.04.2018 – New imaging technology
Georg Thieme Verlag KG Stuttgart · New York

DISTORTION-FREE IMAGING THROUGH WAVEFRONT SENSING TECHNIQUE IN GASTROINTESTINAL ENDOSCOPE: IN VITRO STUDY

JM Lee
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
G Min
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
W Kim
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
SJ Choi
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
JM Lee
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
SH Kim
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
HS Choi
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
ES Kim
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
B Keum
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
YT Jeen
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
HJ Chun
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
HS Lee
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
,
CD Kim
1   Division of Gastroenterology and Hepatology, Department of Internal Medicine, Korea University College of Medicine, Seoul, Korea, Republic of
› Author Affiliations
Further Information

Publication History

Publication Date:
27 March 2018 (online)

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Aims:

Precise measurement of lesion is important in the endoscopic examination. An endoscope is usually equipped with a wide-angle lens (Fish eye lens) which create hidden distortion of image by creating a relative compression of points in its periphery.. In this study, we aims to compare difference between lens applied wavefront sensing technique and conventional lens.

Methods:

We employ wavefront measurement technique for compensation of the distortion of an imaging lens attached to a capsule-type endoscope to obtain a high-resolution and high-contrast image. As a pre-calibration step, the characteristics of the aberration of the endoscope imaging lens were measured using a digital holographic method based on interferometry with a laser light source. And the distortion of the imaging lens was removed by the numerical image processing with the prior information from the pre-calibration.

Results:

We successfully restore the distortion-free image from the unusually stretched image while maintaining the field of view. And, we obtained high degree of contrast compared with LED image and corrected distortion in edges of LED image. In addition, we reconstructed some part of a sample located on the edge, compared with an uncorrected image using LED as light source. The correlation factors of imaging which indicate similarity to the original image, closing to 1 are 0.4918 (Conventional lens), 0.7475 (reconstructed image). These results means that our reconstructed images are 1.5 times closer to original image than conventional lens. We also analyzed the image through line profiling method which can calculate intensity of image. There results means that reconstructed image have a better contrast than conventional lens image.

Conclusions:

We obtained the distortion-free image with wavefront sensing technique, which are closer to original image. Novel wavefront sensing technique is helpful for obtaining corrected image in an endoscope.