상세정보
학술지
Fast Focus Estimation Using Frequency Analysis in Digital Holography
- 발행일
- 201411
- 출처
- Optics Express, v.22 no.23, pp.28926-28933
- ISSN
- 1094-4087
- 출판사
- Optical Society of America(OSA)
- 초록
- A novel fast frequency-based method to estimate the focus distance of digital hologram for a single object is proposed. The focus distance is computed by analyzing the distribution of intersections of smoothed-rays. The smoothed-rays are determined by the directions of energy flow which are computed from local spatial frequency spectrum based on the windowed Fourier transform. So our method uses only the intrinsic frequency information of the optical field on the hologram and therefore does not require any sequential numerical reconstructions and focus detection techniques of conventional photography, both of which are the essential parts in previous methods. To show the effectiveness of our method, numerical results and analysis are presented as well.
- KSP 제안 키워드
- Digital hologram, Focus detection, Frequency information, Frequency spectrum, Intrinsic frequency, Numerical results, Optical field, Spatial Frequency, detection techniques, digital holography, energy flow