Signal-to-Noise Ratio Improvement of EMCCD Cameras

Over the past years, the EMCCD has had a profound influence on photon starved imaging applications relying on its unique multiplication register based on the impact ionization effect in the silicon. High signal-to-noise ratio (SNR) means high image quality. Thus, SNR improvement is important for the EMCCD. This work analyzes the SNR performance of an EMCCD with gain off and on. In each mode, simplified SNR models are established for different integration times. The SNR curves are divided into readout noise (or CIC) region and shot noise region by integration time. Theoretical SNR values comparing long frame integration and frame adding in each region are presented and discussed to figure out which method is more effective. In order to further improve the SNR performance, pixel binning is introduced into the EMCCD. The results show that pixel binning does obviously improve the SNR performance, but at the expensive of the spatial resolution.

Authors:

• Wen W. Zhang
• Qian Chen
• Bei B. Zhou
• Wei J. He

Keywords:

• EMCCD
• SNR improvement
• pixel binning

References:

[1] A. O-Grady, "A comparison of EMCCD, CCD and emerging
technologies optimized for low light spectroscopy applications" , in Proc.
SPIE Biomedical Vibrational Spectroscopy III: Advances in Research and
Industry, 2006, pp. 60930S1-9.
[2] P. JERRAM, P. POOL, R. BELL, et al.. "The LLLCCD: low -light
imaging without the need for an intensifier," in Proc. SPIE Sensors and
Camera Systems for Scientific, Industrial, and Digital Photography
Applications II, 2001, vol. 4306, pp. 178-186.
[3] Digital Camera Fundamentals. Andor Technology.
http://www.andor.com/pdfs/Digital%20Camera%20Fundamentals.pdf
[4] P. A. Jerram, P. J. Pool, D. J. Burt, et al., "Electron Multiplying CCDs", in
Proc. SNIC Symposium , 2006, pp. 1-6.
[5] P. J. Pool, D. G. Morris, D. J. Burt, R. T. Bell, A. D. Holland, et al.,
"Application of electron multiplying CCD technology in space
instrumentation", in Proc. SPIE Focal Plane Arrays for Space Telescopes
II, 2005, pp. 59020A1-6.
[6] N. Smith, C. Coates, A. Giltinan, J. Howard, A. O'Connor, et al.,
"EMCCD Technology and its Impact on Rapid Low-Light Photometry",
in Proc. SPIE Optical and Infrared Detectors for Astronomy, 2004, pp.
162-172.
[7] S. Tulloch, "Modelling the suitability of EMCCDs for spectroscopic
applications", in Proc. SPIE High Energy, Optical, and Infrared
Detectors for Astronomy III Marseille, 2008, pp. 70212C1-10.
[8] T. C. Soesbe, M.A. Lewis, E. Richer, et al., "Development and Evaluation
of an EMCCD Based Gamma Camera for Preclinical SPECT Imaging",
IEEE Trans. Nuclear Science, vol. 50, pp. 1227-1232, May. 2003.
[9] Wen W. Zhang, Qian Chen. Optimum Signal-to-noise Ratio Performance
of Electron Multiplying Charge Coupled Devices. World Academy of
Science, Engineering and Technology, vol. 54, pp. 264-268, June. 2009.
[10] Pixel Binning. http://www.ccd.com/ccd103.html