OSA's Digital Library

Applied Optics

Applied Optics


  • Editor: Joseph N. Mait
  • Vol. 48, Iss. 32 — Nov. 10, 2009
  • pp: 6195–6201

Improved differential confocal microscopy with ultrahigh signal-to-noise ratio and reflectance disturbance resistibility

Jian Liu, Jiubin Tan, Hu Bin, and Yuhang Wang  »View Author Affiliations

Applied Optics, Vol. 48, Issue 32, pp. 6195-6201 (2009)

View Full Text Article

Enhanced HTML    Acrobat PDF (1010 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



Improved differential confocal microscopy is proposed to improve axial resolution and to enhance disturbance resistibility of confocal microscopy. The subtraction and sum values of the two defocusing detected signals are divided as the response function. Both ultrahigh signal-to-noise ratio (SNR) and wide range can be selectively obtained by controlling the defocusing amount of the two differential detectors more tightly with the reflectance disturbance resistibility. Since the detecting sensitivity of the proposed confocal microscopy is unrelated to the energy loss of the reflected beam, the multiplicative mode disturbance can be used to measure microstructures made of hybrid materials and overcome the power drift of a laser source during long scanning. In the case of ultrahigh SNR, the axial resolution reaches 1 nm when NA = 0.75 and λ = 632.8 nm .

© 2009 Optical Society of America

OCIS Codes
(180.1790) Microscopy : Confocal microscopy
(180.3170) Microscopy : Interference microscopy
(180.5810) Microscopy : Scanning microscopy

ToC Category:

Original Manuscript: June 3, 2009
Revised Manuscript: October 2, 2009
Manuscript Accepted: October 16, 2009
Published: November 3, 2009

Virtual Issues
Vol. 4, Iss. 13 Virtual Journal for Biomedical Optics

Jian Liu, Jiubin Tan, Hu Bin, and Yuhang Wang, "Improved differential confocal microscopy with ultrahigh signal-to-noise ratio and reflectance disturbance resistibility," Appl. Opt. 48, 6195-6201 (2009)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. B. V. R. Tata and B. Raj, “Confocal laser scanning microscopy: Applications in material science and technology,” Bull. Mater. Sci. 21, 263-278 (1998). [CrossRef]
  2. S. G. Li, Z. G. Xu, I. Reading, S. F. Yoon, Z. P. Fang, and J. Zhao, “Three dimensional sidewall measurements by laser fluorescent confocal microscopy,” Opt. Express 16, 4001-4014 (2008). [CrossRef] [PubMed]
  3. F. H. Köklü, J. I. Quesnel, and A. N. Vamivakas, “Widefield subsurface microscopy of integrated circuits,” Opt. Express 16, 9501-9506 (2008). [CrossRef] [PubMed]
  4. W. C. Warger and C. A. DiMarzio, “Dual-wedge scanning confocal reflectance microscope,” Opt. Lett. 32, 2140-2142(2007). [CrossRef] [PubMed]
  5. B. J. Davis, W. C. Karl, A. K. Swan, M. Ünlü, and B. Goldberg, “Capabilities and limitations of pupil-plane filters for superresolution and image enhancement,” Opt. Express 12, 4150-4156 (2004). [CrossRef] [PubMed]
  6. C. J. R. Sheppard, “Fundamentals of superresolution,” Micron 38, 165-169 (2007). [CrossRef]
  7. T. Wilson, R. Juškaitis, M. A. A. Neil, and M. Kozubek, “Confocal microscopy by aperture correlation,” Opt. Lett. 21, 1879-1881 (1996). [CrossRef] [PubMed]
  8. J. Tan and F. Wang, “Theoretical analysis and property study of optical focus detection based on differential confocal microscopy,” Meas. Sci. Technol. 13, 1289-1293 (2002). [CrossRef]
  9. W. Q. Zhao, J. B. Tan, and L. R. Qiu, “Bipolar absolute differential confocal approach to higher spatial resolution,” Opt. Express 12, 5013-5021 (2004). [CrossRef] [PubMed]
  10. W. Q. Zhao, J. B. Tan, and L. R. Qiu, “Tri-heterodyne confocal microscope with axial superresolution and higher SNR,” Opt. Express 12, 5191-5197 (2004). [CrossRef] [PubMed]
  11. K. H. Kwon, B. S. Kim, and K. Cho, “A new scanning heterodyne interferometer scheme for mapping both surface structure and effective local reflection coefficient,” Opt. Express 16, 13456-13464 (2008). [CrossRef] [PubMed]
  12. D. Lin, Z. Liu, R. Zhang, J. Yan, C. Yin, and Y. Xu, “Step-height measurement by means of a dual-frequency interferometric confocal microscope,” Appl. Opt. 43, 1472-1479(2004). [CrossRef] [PubMed]
  13. T. Wilson and A. R. Carlini, “Effect of detector displacement in confocal imaging system,” Appl. Opt. 27, 3791-3799(1988). [CrossRef] [PubMed]
  14. http://www.pi-china.cn/pdf/pdf/PI_Piezo_NanoPositioners_Section.pdf.

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited