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In this paper, we present a family of large format CIS’s designed for dental x-ray applications. The CIS areas vary from small 31.5mm x 20.1mm, to medium 34.1mm x 26.3mm, to large 37.1mm x 26.3mm. Pixel size is 19.5um x 19.5um. The sensor family was fabricated in a 0.18um CIS process. Stitching is used in the CIS fabrication for the medium and large size sensors. We present the CIS and detector system design that includes pixel circuitry, readout circuitry, x-ray trigger mechanism, scintillator, and the camera electronics. We also present characterization results including the detector performances under both visible light and x-ray radiation.

As bio-technology transitions from research and development to high volume production, dramatic improvements in image sensor performance will be required to support the throughput and cost requirements of this market. This includes higher resolution, higher frame rates, higher quantum efficiencies, increased system integration, lower read-noise, and lower device costs. We present the performance of a recently developed low noise 2048(H) x 2048(V) CMOS image sensor optimized for scientific applications such as life science imaging, microscopy, as well as industrial inspection applications. The sensor architecture consists of two identical halves which can be operated independently and the imaging array consists of 4T pixels with pinned photodiodes on a 6.5μm pitch with integrated micro-lens. The operation of the sensor is programmable through a SPI interface. The measured peak quantum efficiency of the sensor is 73% at 600nm, and the read noise is about 1.1e- RMS at 100 fps data rate. The sensor features dual gain column parallel ouput amplifiers with 11-bit single slope ADCs. The full well capacity is greater than 36ke-, the dark current is less than 7pA/cm 2 at 20°C. The sensor achieves an intra-scene linear dynamic range of greater than 91dB (36000:1) at room temperature.

In this paper, we present a CMOS digital intra-oral sensor for x-ray radiography. The sensor system consists of a custom CMOS imager, custom scintillator/fiber optics plate, camera timing and digital control electronics, and direct USB communication. The CMOS imager contains 1700 x 1346 pixels. The pixel size is 19.5um x 19.5um. The imager was fabricated with a 0.18um CMOS imaging process. The sensor and CMOS imager design features chamfered corners for patient comfort. All camera functions were integrated within the sensor housing and a standard USB cable was used to directly connect the intra-oral sensor to the host computer. The sensor demonstrated wide dynamic range from 5uGy to 1300uGy and high image quality with a SNR of greater than 160 at 400uGy dose. The sensor has a spatial resolution more than 20 lp/mm.

We present the performance of a CMOS image sensor optimized for next generation fused day/night vision systems. The device features 5T pixels with pinned photodiodes on a 6.5μm pitch with integrated micro-lens. The 5T pixel architecture enables both correlated double sampling (CDS) to reduce noise for night time operation, and a lateral antiblooming drain for day time operation. The measured peak quantum efficiency of the sensor is above 55% at 600nm, and the median read noise is less than 1e- RMS at room temperature. The sensor features dual gain 11-bit data output ports and supports 30 fps and 60 fps. The full well capacity is greater than 30ke-, the dark current is less than 3.8pA/cm 2 at 20oC, and the MTF at 77 lp/mm is 0.4 at 550nm. The sensor also achieves an intra-scene linear dynamic range of greater than 90dB (30000:1) for night time operation, and an inter-scene linear dynamic range of greater than 150dB for complete day/night operability.

In this paper we describe a 5.5Mpixel 100 frames/sec wide-dynamic-range low-noise CMOS image sensor (CIS) designed for scientific applications. The sensor has 6.5μm pitch 5T pixels with pinned photodiodes and integrated microlenses. The 5T pixel architecture enables low noise rolling and global shutter operation. The measured peak quantum efficiency of the sensor is greater than 55% at 550nm, the Nyquist MTF is greater than 0.4 at 550nm, and the linear full well capacity is greater than 35ke-. The measured rolling and global shutter readout noise are 1.28e- RMS and 2.54e- RMS respectively at 30 f/s and 20°C. The pinned photodiode dark current is less than 3.8pA/cm2 at 20°C. The sensor achieves an intra-scene linear dynamic range in rolling shutter operation of greater than 86dB (20000:1) at room temperature. In global shutter readout the shutter efficiency is greater than 1000:1 with 500nm illumination.

In this paper we present a VNIR solid state sensor technology suitable for next generation fused night vision systems. This technology is based on a highly optimized low power 0.18um CMOS image sensor (CIS) process. We describe a 320(H) x 240(V) pixel prototype sensor based on this technology. The sensor features 5T pixels with pinned photodiodes on a 6.5μm pitch with integrated micro-lens. The 5T pixel architecture enables both correlated double sampling (CDS) and a lateral anti-blooming drain. The measured peak quantum efficiency of the sensor is greater than 50% at 600nm, and the read noise is less than 1e- RMS at room temperature. The sensor does not have any multiplicative noise. The full well capacity is greater than 40ke-, the dark current is less than 3.8pA/cm2 at 20oC, and the MTF at 77 lp/mm is 0.4 at 600nm. The sensor also achieves an intra-scene linear dynamic range of greater than 90dB (30000:1) at room temperature.

We present the design and test results of a prototype 4T CMOS image sensor fabricated in 0.18-µm technology featuring 20 different 6.5 µm pixel pitch designs. We review the measured data which clearly show the impact of the pixel topologies on sensor performance parameters such as conversion gain, read noise, dark current, full well capacity, non-linearity, PRNU, DSNU, image lag, QE and MTF. Read noise of less than 1.5e- rms and peak QE greater than 70%, with microlens, are reported.

We present a CCD / CMOS hybrid focal plane array (FPA) for low light level imaging applications. The hybrid approach combines the best of CCD imaging characteristics (e.g. high quantum efficiency, low dark current, excellent uniformity, and low pixel cross talk) with the high speed, low power and ultra-low read noise of CMOS readout technology. The FPA is comprised of two CMOS readout integrated circuits (ROIC) that are bump bonded to a CCD imaging substrate. Each ROIC is an array of Capacitive Transimpedence Amplifiers (CTIA) that connect to the CCD columns via indium bumps. The proposed column parallel readout architecture eliminates the slow speed, high noise, and high power limitations of a conventional CCD. This results in a compact, low power, ultra-sensitive solid-state FPA that can be used in low light level applications such as live-cell microscopy and security cameras at room temperature operation. The prototype FPA has a 1280 x 1024 format with 12-um square pixels. Measured dark current is less than 5.8 pA/cm 2 at room temperature and the overall read noise is as low as 2.9e at 30 frames/sec.