Contact Us

Wymke Ockenga

Wymke Ockenga

Wymke Ockenga studied Human Biology at the Philipps-Universität in Marburg. Her main subjects were cell biology and biological chemistry. She did her diploma thesis at the Institute for Cytobiology and Cytopathologie and is currently working as a PhD student at the Justus-Liebig-Universität in Gießen.

Image of a tartaric-acid crystal taken with polarization microscopy. Tartaric acid, a diprotic, aldaric carboxylic acid, is a naturally occurring organic compound notably found in grapes.

The Polarization Microscopy Principle

Polarization microscopy is routinely used in the material and earth sciences to identify materials and minerals on the basis of their characteristic refractive properties and colors. In biology,…
Fluorescence microscope image of a life-science specimen

An Introduction to Fluorescence

This article gives an introduction to fluorescence and photoluminescence, which includes phosphorescence, explains the basic theory behind them, and how fluorescence is used for microscopy.
Neurons imaged with DIC contrast.

Differential Interference Contrast (DIC) Microscopy

This article demonstrates how differential interference contrast (DIC) can be actually better than brightfield illumination when using microscopy to image unstained biological specimens.
Image of MDCK (Madin-Darby canine kidney) cells taken with phase contrast.

Phase Contrast and Microscopy

This article explains phase contrast, an optical microscopy technique, which reveals fine details of unstained, transparent specimens that are difficult to see with common brightfield illumination.
A 17th-century compound microscope (© Golub Collection – University of California, Berkeley/Steven Ruzin, Curator)

A Brief History of Light Microscopy

The history of microscopy begins in the Middle Ages. As far back as the 11th century, plano-convex lenses made of polished beryl were used in the Arab world as reading stones to magnify manuscripts.…
Cleaning microscope optics

How to Clean Microscope Optics

Clean microscope optics are essential for obtaining good microscope images. If they are dirty, the microscope should be cleaned to avoid a loss of quality. If you decide to do this yourself, you…
TIRF Image of Tubulin, YFP, penetration depth: 120 mm

Applications of TIRF Microscopy in Life Science Research

The special feature of TIRF microscopy is the employment of an evanescent field for fluorophore excitation. Unlike standard widefield fluorescence illumination procedures with arc lamps, LEDs or…
TIRF image of brest carcinoma tumor cells expressing GFP tagged cell adhesion Molecule CD44 that is expressed on the cell membrane, imagined in TIRF.

Total Internal Reflection Fluorescence (TIRF) Microscopy

Total internal reflection fluorescence (TIRF) is a special technique in fluorescence microscopy developed by Daniel Axelrod at the University of Michigan, Ann Arbor in the early 1980s. TIRF microscopy…
Section taste buds rabbit, differential interference contrast microscope

Optical Contrast Methods

Optical contrast methods give the potential to easily examine living and colorless specimens. Different microscopic techniques aim to change phase shifts caused by the interaction of light with the…
Transgenic Mouse Embryo, GFP

Fluorescence in Microscopy

Fluorescence microscopy is a special form of light microscopy. It uses the ability of fluorochromes to emit light after being excited with light of a certain wavelength. Proteins of interest can be…
Scroll to top