| 摘要 |
PURPOSE:To perform exact focusing detection over a wide defocusing range by disposing photoelectric transducer arrays on the respective photodetection surfaces at which the light past each slope of a micro critical angle array arrives and providing means for calculating the sum of the output from the selected photodetection region. CONSTITUTION:The angle theta between the slope of a critical angle prism 10 and photodetector arrays An.i, Bn.i (i=1, 2, n is a natural number) is made small and the photodetectors An, Bn are bisected to An.1, An.2 and Bn.1 and Bn.2. An evaluation value is calculated with the sum of the outputs of the photodetection region An.1 and An.2 as the output of the photodetector An and the sum of the outputs of Bn.1 and Bn.2 as the output of Bn for a lens having a small F number. An evaluation value is calculated only from the outputs of An.1, Bn.1 for the lens having a large F number. The quantity of a lateral deviation is controlled in accordance with the above-mentioned evaluation determined with transfer gates TAn.1, TAn.1, TBn.1, TBn.2 and an adder ADD, whereby the sure focusing detection is accomplished over a wide defocusing range. |
