| 摘要 |
PROBLEM TO BE SOLVED: To provide an image capturing optical system unit which features compactness, low cost, reduced color unevenness, and reduced generation of stray light caused by an infrared cut filter (IRCF), and to provide an image capturing device and digital device having the same.SOLUTION: An image capturing optical system unit 1 includes: an image capturing optical system 10; and an IRCF 16. The image capturing optical system 10 has a lens 15 which is located on the most image side and has an aspherical surface corresponding to an outline of a lens cross-section having at least one inflection point P. Distance h from an optical axis to the inflection point P and distance TL from a most object side surface to an imaging position satisfy 0.2<h/TL<0.4. IRCF 16 satisfies |λ(0,50)-λ(30,50)|≤15nm for a wavelengthλ(α,50), in a range of 600-700 nm, at which reflectance is 50% forα-degree incident light, and satisfies 0.3%/nm≤|▵R|≤8%/nm for▵R representing a slope of a reflectance difference over a wavelength difference between two wavelengths at which reflectance is 30% and 70%, respectively, for zero-degree incident light. |
