OTTAWA–Sony has introduced a new 4/3-inch CMOS sensor for 4K surveillance that also enables HDR.
The IMX294 image sensor is optimized to be used in security cameras and industrial applications. The back-illuminated CMOS Starvis sensor achieves a 4K resolution with 10.7 megapixels at a high frame rate of 120 fps. Available from the global imaging specialist FRAMOS, IMX294 has an excellent SNR1s value (a Sony proprietary index limited to CMOS sensors for security applications), and enables HDR shots with minimal movement artifacts thanks to the Quad Bayer pixel structure.
The image sensor adopts the standardized 4/3-inch optical format, offering various combinations of output formats: 10 megapixels (3,704 x 2,778) for 4:3 ratio, UHD (3,840 x 2,160) for 16:9 and 4,096 x 2,160 pixels for the 17:9 image format. Depending on the application’s requirements, it is possible to select a color depth of 10, 12 or 14 bits. The extraordinary low-illumination performance of 0.14lx for SNR1s is achieved by the large 4.63 μm pixel size. This makes IMX294 ideal for applications with low incident light, eliminating the need of additional illumination.
Figure 1 IMX294 Quad Bayer CFA pixel structure
FRAMOS Sony sensor expert Anna Neschitsch explains the advantages of the new 4K sensor: “With a frame rate of 120 fps at 10 bits and a 4K resolution, the IMX294 is ideal for high-speed video applications. For applications with higher sensitivity requirements, the new sensor still achieves an excellent frame rate of 60 fps in HDR mode, making it perfect for surveillance applications. Its high sensitivity of 1,700 mV and high saturation of 970 mV values ensure very high quality for image analysis and evaluation, particularly in low light conditions. In addition, the proprietary high-speed SLVS-EC interface enables image transmission over fewer signal lines. This sensor is additionally equipped with a universal MIPI (CSI-2) interface and supports the connection to an all-purpose ISP (image signal processor) for direct preprocessing of data.”
The IMX294 uses a Quad Bayer structure which outputs 2×2 binned pixels in normal mode. In HDR mode, two pixels of the quad array are used for a short exposure and the other two for a long one (Fig. 1). This eliminates the temporal delay between short and long exposures seen in common two image HDR implementations, resulting in HDR images with minimal artifacts when imaging moving objects. (Fig. 2).
The industry and product experts at FRAMOS have specialized knowledge ranging from sensor to full imaging system, and provide complete support for the integration of new sensors into their applications. The Sony IMX294 works well with lenses such as the LMXC series from Kowa, as well as the Computar MPY series. FRAMOS also offers additional services such as development support, cover glass removal, as well as storage and logistics services.