A Low-Light CMOS Contact Imager With an Emission Filter for Biosensing Applications
In the article is described a fully functional low light 128 128
contact image sensor for cell detection in biosensing applications. 0.18micrometer CMOS technology is used to fabricate it. It has a low-noise operation by employing both a modified version
of the active reset (AR) technique. for
fluorescence imaging, we need High-sensitivity and low noise performance. These attributes are inegrated into this sensor. an emission filter is specially fabricated using PDMS and Sudan II Blue dye mix, spin-coated and
deposited in a class 1000 clean room and integrated into the sensor. The wavelength of excitation should be 340 nm and emission at 450 nm
and above.

INTRODUCTION
In the technique of contact imaging , the sample of interest
is directly placed over the top of a sensor array. The major difference and advantage of this technique over conventional imaging is that this technique do not require optical elements like lenses. This decreases the optical loss. But the minimum sample size is limited. Fluorescence imaging is a selective and quantitative method
that is widely used in areas such as cell analysis, diagnosis,
bioengineering, and pharmaceutical and genomic research. Photomultiplier tube or CCD are the generally used equipment for converting the light into electrical pulses. In state-of-the-art CMOS imagers, timing, exposure control, color processing, image enhancement,
image compression and analog-to-digital (ADC) conversion all can be integrated on the chip itself.

report pdf:
http://filesonicfile/22656149/Low-Light CMOS Contact Imager With an Emission Filter for Biosensing Applications.pdf