Title :
A CMOS active-pixel image sharpness sensor
Author :
Rayankula, Aditya ; Furth, Paul M.
Author_Institution :
Klipsch Sch. of Electr. & Comput. Eng., New Mexico State Univ., Las Cruces, NM, USA
Abstract :
The technique of maximizing image sharpness is a powerful means of adaptively correcting phase aberrations in wavefronts. Crucial to this correction is a sensor that provides an accurate real-time estimate of image sharpness. In this paper, we introduce a novel image sharpness sensor using CMOS active pixel technology that computes image sharpness at a sample rate of 7.8 kHz. The sharpness sensor contains a 40×40 pixel array and is fabricated in a 0.5-μm CMOS process through MOSIS. Power consumption is 12 mW. Each pixel is 24.5 × 24.5 μm2 with a fill factor of 20%. Experimental results obtained under open-loop static conditions show that the output value changes by 87.5% when the sensor is moved 1 cm away from the 50-cm focal point. This sensor finds potential applications in closed-loop adaptive optics systems.
Keywords :
CMOS image sensors; power consumption; CMOS active-pixel image sharpness sensor; MOSIS; fill factor; frequency 7.8 kHz; open-loop static conditions; phase aberrations; power 12 mW; power consumption; size 0.5 mum; wavefronts; Adaptive optics; CMOS integrated circuits; Laser beams; Lenses; Measurement; Threshold voltage; Transistors; CMOS image sensor; Image sharpness; active-pixel; adaptive optics; image quality metric; wavefront sensor;
Conference_Titel :
Circuits and Systems (MWSCAS), 2014 IEEE 57th International Midwest Symposium on
Conference_Location :
College Station, TX
Print_ISBN :
978-1-4799-4134-6
DOI :
10.1109/MWSCAS.2014.6908569
