| 摘要 |
PROBLEM TO BE SOLVED: To improve focusing accuracy in a phase difference detection focus detector by reducing the lowering of the symmetric property of the parallel displacement of phase waveform caused by a guided output signal from a photoelectric conversion element in the lowering of light quantity caused at the peripheral parts of respective two images obtained by forming the image in a secondary image formation system on the photoelectric conversion element. SOLUTION: By providing a field lens 12 for condensing an incident light beam, a 1st diaphragm mask 15 for separating the light beam and forming it into an image again, and image re-forming lenses 16a and 16b, providing the photoelectric conversion means 17 for outputting the phase waveform by receiving the two separated images, and disposing a 2nd diaphragm mask 14 selecting the light beam necessary for focus detection from the light beam primarily formed into the image by an objective lens 11 by separating it in an optical axis direction, the symmetric property of the output phase waveform of two images in each photoelectric conversion element 17 is excellently corrected. |
