Untersuchung eines bionischen Infrarot-Detektors nach dem Vorbild der infrarotempfindlichen Sensillen des Schwarzen Kiefernprachtkaefers Melanophila acuminata

摘要

The larvae of the beetle Melanophila acuminata need freshly burnt wood for their development. For the location of forest fires the beetle uses a pair of metathoracic pit organs. About 70 dome-shaped infrared-sensitive sensilla are located in each pit measuring IR radiation in the wavelength interval of 2 – 4 μm. A single sensillum consists of a massive hollow sphere consisting of hard exocuticle, which encloses a microfluidic core. The pressure - sensitive tip of a mechanosensitive neuron is connected to this inner compartment. Incoming IR radiation heats up the sphere which causes an increase in temperature and hence in internal pressure increase. This increase in pressure is measured by the mechanoreceptor. A system of small nanopores extends through the outer wall of the hollow sphere. Most probably these canals serve for the compensation of occasional changes in ambient temperature. The well-known Golay cell is a first approach to describe the working principle of the sensillum, if the gas of the Golay cell is replaced by a fluid. As a read-out the deflection of the bottom of the cell is used. The influence of different fluids on the deflection of the bottom and the design of the nanocanals are presented.