We introduce a procedure to calibrate an inexpensive, commercial camera for optical power measurements. This allows the use of the camera as a very sensitive optical power meter that is able to measure powers down to the femtowatt level. A windowing technique, based on the selection of a region of interest from the total sensor area, is used to maintain a good signal-to-noise ratio over a large range of the measured optical powers. The increase of the exposure time of the camera shifts its detection limit to lower powers. Using this calibration procedure and the windowing technique, we measured 25 fW of optical power with a common complementary metal-oxide-semiconductor camera.
© 2014 Optical Society of America
Original Manuscript: June 19, 2014
Revised Manuscript: July 14, 2014
Manuscript Accepted: July 18, 2014
Published: August 15, 2014
Silviu T. Popescu, Petronela S. Gheorghe, and Adrian Petris, "Measuring very low optical powers with a common camera," Appl. Opt. 53, 5460-5464 (2014)