My research interest is in instrumentation for gravitational wave detectors, and how these complex machines can be made more sensitive and reliable. Interferometric gravitational wave detectors embody phyiscs and engineering from many disciplines, like mechanics, optics, control systems, electronics, computing, solid state physics, and vacuum technology. Examples of my particular interests are: Improving the readout methods with which gravitational wave information is obtained from the optical output of what we call the main interferometer, understanding and improving the complex alignment system of gravitational wave detectors that hold all optics at their correct angles at all times, and researching ways to reduce the quantum noise in interferometers. I also have an interest in the application of precision interferometry techniques to other fundamental physics questions, like the measurement of birefringence of the vacuum, the search for new particles beyond the standard model, and more exotic questions. One of them is the question wether we can observe signatures of quantization of space-time with laser interferometry. We are constructing a table-top interferometer in our group, that will search for quantization of space-time, for scalar field dark matter and for ultra-high frequency gravitational waves.