Table 1.
Fundamental performance of silicon image sensors (expressed by round numbers).
| Resolution | Dynamic Range | |||
|---|---|---|---|---|
| A Ultimate |
B State-of-the-Art |
B/A | ||
| Sensitivity | 1 photon (1 e−) * | 1 e− (0.3 e− rms) * | 1 | SN ratio |
| Spatial | 0.3 µm ** | 1 µm | 3 | Pixel Count |
| Temporal | 10 ps | 10 ns *** | 1000 | Frame Count |
* If the quantum efficiency is one, one photon generates one electron. To detect one electron at a sufficiently high confidence level, the readout noise level of about 0.3 e− rms is required [8]. ** The Rayleigh criterion for the wavelength of 550 nm. *** The achievement presented in this paper. Photon-counting-type image sensors, such as SPAD, have achieved 100 ps [9]. However, repetitive imaging is necessary to get an image with these sensors [4].