| 摘要 |
PURPOSE:To attain smooth and high speed automatic focusing by predicting a focusing point from the intersected point of two kinds of loci whose parameter setting points mutually differ and whose focus voltages are coincident or approximate in the focusing point. CONSTITUTION:Two loci whose parameter setting points mutually differ and whose focus voltages are coincident or approximate in the focusing point are obtained. Correction AMP 5 is inserted into an extraction part 1, and extracted high frequency components are amplified to an appropriate level. Only the signal of a prescribed view range passes through an area circuit 8 and it comes to focus information in an integrating circuit 9. AMP 5 corrects the level of a luminance signal, generates the second locus and it is used for predicting the focusing point. In a control part 2, the light of a subject is taken into a light-measurement element 10, is amplified in light measurement AMP 11 to the appropriate level and is transmitted to a micro computer 17 as luminance information. Then, the approximate expression of two loci is calculated and a lens is moved to a focus voltage corresponding position at high speed by a lens motor 16. Thus, smooth and high speed automatic focusing is attained. |
