Abstract: An optical element comprises a planoconvex basic shape along an optical axis of the optical element; a third portion arranged between a first portion and a second portion. The first portion includes a plane side face for facing an object to be imaged. The second portion includes a convexly shaped side face for facing an image plane. The plane side face of the first portion is designed to collect and steer a radiation to be captured into the optical element, the optical element being designed to guide rays of the captured radiation in a beam path. The first, the second and the third portions are arranged directly adjacent to one another. A refractive index of the third portion is greater than a refractive index of the second portion, and the refractive index of the second portion is greater than a refractive index of the first portion.

Abstract: A finity-corrected microscope objective for scanning applications has a numerical aperture of at least and an object field diameter of at least 1 mm. The objective is apochromatically corrected over a spectral bandwidth of at least 200 nm. A distance between an object plane and an intermediate image plane conjugated thereto is not more than 250 mm.

Abstract: An infinity-corrected microscope objective for scanning applications has a relatively small number of lenses that are dependent on the etendue such that the objective has: i) a first etendue in the range of 0.8 mm2 to 1.8 mm2 and a maximum of nine lenses; or ii) a second etendue in the range of more than 1.8 mm2 and not more than 15 lenses.