WORKSHOP PAPER
On the determination threshold of illumination-adaptive signal selection technology for multi-stage LOFIC CMOS image sensors
Yoshihito Hirai1,2, Kohei Takizawa1, Takezo Mawaki1, Rihito Kuroda1
1Graduate School of Engineering, 6-6-05, Aza-Aoba, Aramaki, Aoba-ku, Sendai, Miyagi, Japan 980-8579
2New Industry Creation Hatchery Center, Tohoku University

Abstract

This paper presents illumination-adaptive signal selection technology for multi-stage LOFIC CMOS image Sensor. The developed CMOS image sensor contains a comparator for determining the amount of overflow electrons. The concept of light intensity determination function is experimentally confirmed. The distribution of dark current at LOFIC and its temperature tendency is shown for the consideration of determination threshold. Furthermore, the activation energy of all pixels was extracted, showing that most pixels are dominated by generation-recombination current. Finally, the result of determination function when the determination threshold is optimized based on the amount of dark current is shown, demonstrating its usefulness.
Year: 2025
Workshop: IISW
URL: https://doi.org/10.60928/wjde-as5j
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Keywords

illumination-adaptive signal selection technology, LOFIC, CMOS image sensor, determination threshold, dark current, activation energy,

References

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