Frits Zernike (; 16 July 1888 – 10 March 1966) was a Dutch physicist and winner of the Nobel Prize in Physics in 1953 for his invention of the phase-contrast microscope.

Early life and education

Frits Zernike was born on 16 July 1888 in Amsterdam, Netherlands to Carl Friedrich August Zernike and Antje Dieperink. Both parents were teachers of mathematics, and he especially shared his father's passion for physics. He studied chemistry (his major), mathematics and physics at the University of Amsterdam.

Academic career

In 1912, he was awarded a prize for his work on opalescence in gases. In 1913, he became the assistant of Jacobus Kapteyn at the astronomical laboratory of Groningen University. In 1914, Zernike and Leonard Ornstein were jointly responsible for the derivation of the Ornstein–Zernike equation in critical-point theory. In 1915, he obtained a position in theoretical physics at the same university and in 1920 he was promoted to full professor of theoretical physics. In 1930, Zernike was conducting research into spectral lines when he discovered that the so-called ''ghost lines'' that occur to the left and right of each primary line in spectra created by means of a diffraction grating, have their phase shifted from that of the primary line by 90 degrees. It was at a Physical and Medical Congress in Wageningen in 1933, that Zernike first described his phase contrast technique in microscopy. He extended his method to test the figure of concave mirrors. His discovery lay at the base of the first phase contrast microscope, built during World War II. He also made another contribution in the field of optics, relating to the efficient description of the imaging defects or aberrations of optical imaging systems like microscopes and telescopes. The representation of aberrations was originally based on the theory developed by Ludwig Seidel in the middle of the nineteenth century. Seidel's representation was based on power series expansions and did not allow a clear separation between various types and orders of aberrations. Zernike's orthogonal circle polynomials provided a solution to the long-standing problem of the optimum 'balancing' of the various aberrations of an optical instrument. Since the 1960s, Zernike's circle polynomials are widely used in optical design, optical metrology and image analysis. Zernike's work helped awaken interest in coherence theory, the study of partially coherent light sources. In 1938 he published a simpler derivation of Van Cittert's 1934 theorem on the coherence of radiation from distant sources, now known as the Van Cittert–Zernike theorem.


He died in the hospital at Amersfoort, Netherlands in 1966 after suffering illness the last years of his life. His granddaughter is journalist Kate Zernike.

Honours and awards

In 1946, Zernike became member of the Royal Netherlands Academy of Arts and Sciences. In 1953, Zernike won the Nobel Prize in Physics, for his invention of the phase-contrast microscope, an instrument that permits the study of internal cell structure without the need to stain and thus kill the cells. In 1954, Zernike became an Honorary Member of The Optical Society (OSA). Zernike was elected a Foreign Member of the Royal Society (ForMemRS). The university complex to the north of the city of Groningen is named after him (Zernike park), as is the crater Zernike on the Moon. Zernike's great-nephew Gerard 't Hooft won the Nobel Prize in Physics in 1999. The Oz Enterprise, a Linux distribution, was named after Leonard Ornstein and Frederik Zernike.

See also

* Leonard Ornstein * Coherence theory * Fourier optics * Live cell imaging * Optical aberration * Phase-contrast X-ray imaging * Physical optics


External links

Frits Zernike Photo
* including his Nobel Lecture, December 11, 1953 ''How I discovered phase contrast''
Extended Nijboer–Zernike theory
* Museum Boerhaav
Negen Nederlandse Nobelprijswinnaars
* H. Brinkman
''Zernike, Frits (1888–1966)''
in Biografisch Woordenboek van Nederland. * Prominente Groningse hooglerare
''Frits Zernike (1888–1966)''

biography at the National library of the Netherlands.

Multilevel wavelet solver for the Ornstein-Zernike equation Abstract

Analytical solution of the Ornstein-Zernike equation for a multicomponent fluid
{{DEFAULTSORT:Zernike, Frits Category:1888 births Category:1966 deaths Category:20th-century physicists Category:Dutch inventors Category:Dutch Nobel laureates Category:Dutch physicists Category:Foreign Members of the Royal Society Category:Members of the Royal Netherlands Academy of Arts and Sciences Category:Microscopists Category:Nobel laureates in Physics Category:Scientists from Amsterdam Category:University of Amsterdam alumni Category:University of Groningen faculty