SNR1s

What's SNR1s ?

Sony is introducing SNR1s [lx] as an index used to quantitatively evaluate picture quality at low illumination. SNR1s [lx] is a proprietary index advocated by Sony, and is limited to CMOS image sensors for security camera applications.
A smaller value indicates better picture quality at low illumination.
SNR1s [lx] is an acronym consisting of "SNR" (Signal-to-Noise Ratio), "1" (represents that the signal level when noise = 1 is 1), and "s" (for Security).

SNR1s [lx] Prescribed Conditions
Application Security Camera
Light Source 3200 [K]
Target Object 18% Grey
F number 1.4
Exposure time 1/60 [s]
Linear Matrix without
Signal G [e-] (Sensor Raw Output)
Noise Shot Noise[e-] 2 + Dark Noise[e-] 2
Signal : Noise 1 : 1

Note:
SNR1s is a new index proposed by Sony for picture quality at low illumination, and is limited to CMOS image sensors for security applications.

Schematic of SNR1s Measurement Method

Figure 1 shows a schematic of SNR1s measurement.
Two 3200 [K] light sources illuminate an 18% gray chart from different directions, and dimming is performed to 100 [lx]. A camera is placed so that the distance from the gray chart to the imaging surface of the image sensor is 1 m, the sensitivity [e-] and dark noise [e-] are measured, and SNR1s [lx] is calculated using the relational equation (1). The luminance when equation (1) equals 1 is SNR1s [lx].
For further details, contact your local Sony sales company.

Numerical formula

Figure1
Fig.1 Schematic of SNR1s Measurement

SNR1s Values of CMOS Image Sensors for Security Applications

  • SNR1s [lx] : A smaller value indicates better picture quality at low illumination.
  • The applicable types are showed as [Surveillance] application in products page in this website.
SNR1s Values of CMOS Image Sensors for Security Applications
Resolution Image size Products SNR1s value
From 8M 1/2
IMX226
STARVIS
0.95 lx
IMX172
STARVIS
1.33 lx
5M to 6M 1/2
IMX178
STARVIS
0.46 lx
3M 1/3
IMX123
STARVIS
0.45 lx
2M to 2.4M 1/2
IMX185
0.20 lx
1/3
IMX290
STARVIS
0.23 lx
IMX323
0.60 lx
1M to 1.3M 1/3
IMX224
0.13 lx

Note:
SNR1s is a new index proposed by Sony for picture quality at low illumination, and is limited to CMOS image sensors for security applications.
Sony reserves the right to change SNR1s values without prior notice.
Sony cannot assume responsibility for any phenomena occurring as a result of using released SNR1s values.