Systems and methods for color correcting radiation by alternately focusing a first radiation spectrum on a first radiation spectrum detector, and then focusing at least one additional radiation spectrum on at least one additional radiation spectrum detector. The optical system is arranged so that a distal side of the fingertip portion is tilted at a predetermined angle, farther away from the optical system thank an opposite sides with reference to a position at which a ventral side of the fingertip portion contacts a face orthogonal to an optical axis of the optical system. A cladding having a refractive index that is higher than the second refractive index and lower than the first refractive index is formed on outer circumference of the outer core. The first resistance-to-displacement value is greater than the second resistance-to-displacement value.