New-Tech Magazine - Europe | January Digital edition

developed to a point where they cap-ture near-perfect imagery. Their advantage compared to the older CCD imagers is that they can be narrowly tailored to their specific application fields. In addition, CMOS sensors, by virtue of their opera-tional principle and established manufacturing processes as CMOS semiconductor devices, integrate on the same chip image capture with multiple support functions. Such support functions include image processing for high dynamic range (HDR), on-chip noise suppression, flexible channel multiplexing, windowing and subsampling, and high-speed LVDS interfacing. All this leads to more compact camera designs, better system interconnect and compatibility, and ease of use. High data throughput is very much in demand for industrial vision, es- pecially in production and inspection tasks. Users want to get as much data off their imagers as possible, asking for the highest possible frame rate for their specific applications. Throughput rates have increased over the past few years from 30 to 60 to about 120

resolution and detail richness in its dedicated field of optical tomogra- phy. It enables in-vivo inspection of human tissue down to the cell level as well as fast ex-vivo microscopy. The CSI2100 wafers are fabricated by the wafer foundry Tower Jazz in Migdal Haemek, Israel. Besides its high full-well capacity the CSI2100 achieves high frame rates up to 700fps by integrating 35 LVDS (Low voltage Differential Signaling) outputs. Dark noise, mainly caused by ADC quantization noise, is held to 945e. Dynamic range is 66dB. The chip, housed in a small µBGA package with 173 pins, has a power consumption of just 2 watts (Figure 3). The new sensor was conceived within the EU-funded FFP7-ICT project "CAReIOCA" (Non-Invasive Optical Biopsy for Cancer Assessment Using Ultra-high Resolution Full-Field Optical Coherence Tomography) started in 2013. The program is continuing at a fast pace developing and eval-uating high-resolution/high-speed medical imaging devices for perform-ing non- invasive optical biopsy procedures by building volumetric imag-es through a Linnik interferometer analysis of the interference patterns of light reflected by the examined tissue and a reference light source via an oscillating mirror. This way, living cells of 5µm in diameter can be captured and examined. A major scientific goal of the CAReIOCA program is to establish atlases of specific FFOCT histology imagery for clinical use, foremost in the di-agnostics and post-surgical evaluation of cancer. This part is carried out by Leiden University, The Netherlands, and Gustave Roussy Institute in Villejuif (Paris). Optical

Figure 1: Sensor CSI2100

biopsy is meant to ease the burden on cancer patients by avoiding the destructive removal of tissue probes for tradi-tional biopsy and histological analysis procedures. By the end of 2014 CAReIOCA had progressed to demonstrating proto-types of a handheld FFOCT endoscope containing the compact 2-MP camera Q-2A750/CXP with CoaXPress interface, integrating the CMOSIS sensor CSI2100. This new diagnostic prototype system shows a 5 times higher processing speed and a 3 times higher sensitivity compared to existing designs. CMOS Sensor Trends CMOS sensors and cameras have

Figure 2: Image sensors are essential for a broad range of digital systems and products

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