CCD vs CMOS Sensor Comparison
Compare CCD, sCMOS, phone CMOS and EMCCD pixels: SNR from photons × QE, saturation and dynamic range.
| Sensor | Read Noise | Dark | FWC | Pixel | QE | Signal | SNR | DR | FPS |
|---|---|---|---|---|---|---|---|---|---|
| CCD | 3 e⁻ | 0.001 e⁻/s | 100k | 15 µm | 95% | 950 e⁻ | 30.7 | 90.5 dB | 10 |
| sCMOS | 1.5 e⁻ | 0.01 e⁻/s | 50k | 6.5 µm | 90% | 900 e⁻ | 30.0 | 90.5 dB | 100 |
| Phone CMOS | 2 e⁻ | 5 e⁻/s | 6k | 1.2 µm | 65% | 650 e⁻ | 25.3 | 69.5 dB | 60 |
| EMCCD | 89 → 0.297 e⁻ | 0.00011 e⁻/s | 180k (reg. 800k) | 16 µm | 95% | 950 e⁻ | 21.9 | 79.1 dB | 56 |
S = QE·N_photons; SNR = S / √(F²·(S + D·t) + (σ_read/G)²)
CCD, CMOS: G = 1, F² = 1. EMCCD: F² = 2(G − 1)·G^(−(N+1)/N) + 1/G, N = 536 (CCD97)
DR = 20·log₁₀(S_max / (σ_read/G)); EMCCD S_max = min(pixel well, register well / G)
Model and references
Textbook approximation. A standard approximation from the literature (for example paraxial, plane-wave or Gaussian-beam), valid within the range the page states. About the tiers
Poisson signal (photons × QE) and dark charge plus Gaussian read noise; the EMCCD adds the Robbins–Hadwen excess noise of the CCD97's 536-stage register and divides the read noise by the gain. Its dynamic range uses the gain-register well, so for G ≳ 4.4 (= 800 000/180 000, register well limited) it stays near 20·log₁₀(800 000/89) = 79 dB, while G = 1 gives 66.1 dB. The sensor values are representative; the EMCCD follows the iXon Ultra 897 sheet. Clock-induced charge, fixed-pattern noise, sCMOS read-noise tails and dual-gain readout are left out.
- Janesick J. R. (2007). Photon Transfer: DN → λ. SPIE Press. Shot, dark and read noise of a sensor pixel; full well and dynamic range. doi:10.1117/3.725073
- Robbins M. S., Hadwen B. J. (2003). The noise performance of electron multiplying charge-coupled devices. IEEE Trans. Electron Devices 50, 1227–1232. F² = 2(G − 1)·G^(−(N+1)/N) + 1/G. doi:10.1109/TED.2003.813462
- Andor (Oxford Instruments). iXon Ultra EMCCD specifications. iXon Ultra 897: 180 000 e⁻ pixel well, 800 000 e⁻ gain-register well, 89 e⁻ read noise at 17 MHz without EM gain. andor.oxinst.com
- Teledyne e2v. CCD97-00 Back Illuminated 2-Phase IMO Series Electron Multiplying CCD Sensor, data sheet A1A-CCD97BI-2P-IMO v6 (2017), p. 5: 536 gain-register elements. teledyneimaging.com