Spherical aberration measurement of a microscope objective by use of calibrated spherical particles.

The purpose of this paper is to characterize the spherical aberration of a microscope objective lens by using diffraction light from nanosphere particles. The experimental image of the diffraction spot of a nanosphere is fitted with the Nijboer-Zernike model to estimate the spherical aberration. The method can easily be extended to the measurement of other and higher-order aberrations.

Digital microscopic holography for micrometer particles in air.

The development of a specific holographic setup designed for providing three-dimensional imaging of micrometer particles in a very small volume inside a large air-flow facility is described. Study of a 1.5 mm(3) volume is made possible with the use of a microscope objective for magnification of the object field.