Abstract: An IGBT includes two trenches extending from an emitter terminal toward a first side of a substrate of a first conductivity material. A collector layer of a second conductivity material is disposed on a second side of the substrate. The trenches each have a gate and a insulator within them. On the outside of the trenches, bulk regions of a second conductivity type are disposed on the first side of the substrate. On top of the bulk regions are bulk connection regions of a second conductivity type and source regions of a first conductivity type. The emitter couples the bulk and source regions. A material of either conductivity type, an insulator, or two MOSFETS are placed between the trenches. With multiple IGBTs, the trenches can be arranged in striped, island-like, or lattice format.

Abstract: In a stationary wave interpolator for detecting very rapid movements of objects with high resolution in real-time operation, the mode distance frequency of a laser is fed to a first conductive path and the mode distance frequency plus/minus the Doppler shift is fed to a second conductive path. The two conductive paths are connected by double balanced mixers which are connected in parallel, whose reference inputs are connected to the first conductive path and whose measurement inputs are connected to the second conductive path. The outputs of the double balanced mixers are connected to a digital discriminator for decoupling a phase-shifted Doppler frequency.

Abstract: Symmetrical carrier frequency interferometer for length, distance and speed measurements with beam-deflecting and beam-splitting elements, as well as a fixed reference mirror and a movable measurement mirror. The optically active surfaces positioned downstream of a first polarization-splitting layer are arranged in mirror-symmetrical manner with respect to the latter. Upstream of a second polarization-splitting layer inclined by 45.degree. a .lambda./2 plate is located in one of the two beam paths and in the passage direction behind said layer are located the .lambda./4 plate, the fixed reference mirror and the movable measurement mirror. There is at least one reversing element in the reflection direction.