Image Sensors on VLSI Circuits Symposium

This year VLSI Circuits Symposium has an image sensor session to be held on June 17 in Kyoto, Japan. The session features a couple of papers on very low voltage and low power sensors and also TI-sponsored research papers on WRGB and HDR sensors:

A Color-Independent Saturation, Linear Response, Wide Dynamic Range CMOS Image Sensor With Retinal Rod-and Cone-Like Color Pixels
S. Kawada, S. Sakai, N. Akahane, K. Mizobuchi and S. Sugawa
Tohoku University and Texas Instruments, Japan

A CMOS image sensor densely and uniformly placed the retinal rod- and cones-like WRGB pixels with lateral overflow integration capacitors having the different sizes in each color has been demonstrated. A 1/3.3-inch, 4.2-um effective pitch, 1280(H) x 480(V) checker-pattern pixels CMOS image sensor was fabricated and has achieved color-independent saturation and about twice the effective sensitivity compared with conventional Bayer-RGB color filter image sensor made at the same time.

A CMOS Image Sensor With 2.5-e– Random Noise and 110-ke– Full Well Capacity Using Column Source Follower Readout Circuits
T. Kohara, W. Lee, N. Akahane, K. Mizobuchi and S. Sugawa
Tohoku University and Texas Instruments, Japan

A low noise CMOS image sensor without degradation of saturation performance has been developed by using column amplifiers of the gains of about 1.0 in a lateral overflow integration capacitor technology. The 1/4-inch, 4.5-um pitch, 800(H) x 600(V) pixels CMOS image sensor fabricated by a 0.18-um 2P3M technology has achieved fully linear response, 0.98 column readout gain, 100-uV/e- conversion gain, 2.5-e- random noise, 110,000-e- full well capacity and 93-dB dynamic range in one exposure.