AU - Shahbazi, Amir Hossein AU - MadaniPour, Khosro AU - Koohian Mohammad Abadi, Ataollah AU - Pazouki, Ehsan TI - Investigating the Defocusing Phenomenon in CCD MTF Measurement Based On PSF Technique PT - JOURNAL ARTICLE TA - opsi JN - opsi VO - 20 VI - 0 IP - 0 4099 - http://opsi.ir/article-1-270-en.html 4100 - http://opsi.ir/article-1-270-en.pdf SO - opsi 0 ABĀ  - In this paper we tried to investigate the Defocusing role in CCD modulation transfer function measurement. To calculating the MTF, point spread function was measured. In experiment, we used a 3W LED with warm white spectra as the broadband source. Finally the effect of the lens relocation on CCD MTF and its cut-off frequencies studied. CP - IRAN IN - LG - eng PB - opsi PG - 585 PT - Research YR - 2014