Abstract: An acoustic testing apparatus for testing a laminate material comprising at least one layer of a first material having a first velocity for a first vibration mode and at least one layer, adjacent to said first layer, of a second material having a velocity for a second vibration mode, approximately equal to said first velocity, said acoustic testing apparatus comprising: a first transducer for projecting an acoustic test signal onto a first layer of said at least one layer of a first material disposed in a testing zone, wherein a second transducer for receiving said test signal from said testing zone, and in that said first transducer is adapted to project said test signal at an angle so as to generate in said first layer vibrations of at least said first vibration mode, wherein said vibrations of said first vibration mode are incident on an interface with said layer of said second material under an incidence angle so as to produce in said second layer vibrations of at least said second vibration mode, so that

Abstract: On the basis of a series of reflection measurements on a liquid, parameters are calculated which describe a particle size distribution of particles in the liquid. In each reflection measurement, a signal beam is generated in the liquid and a value of a property such as the amplitude of a reflection on a particle in the signal beam is measured. Using maximum likelihood estimation, the parameters of the particle size distribution are estimated, on the basis of an expression for a probability of the measured values as a function of the measured values. The expression used contains a first factor for the probability of a reflection measurement of which a reflection with the measured value forms part, corrected with a second factor for the probability that there is not also a reflection with a dominating value of the property, which would mask the measured values, forming part of the reflection measurement.

Abstract: In an immersion lithography apparatus, ultrasonic waves are used to atomize liquid on a surface of the substrate.

Abstract: A method for characterizing a suspension with particles floating therein, which method comprises the steps of generating an acoustic actuation signal and registering an acoustic reflected signal. Further, a first dataset is calculated on the basis of the reflected signal, the dataset containing information which represents an autocorrelation function as a function of time of the reflected signal. Thereupon, first datasets are combined into a second, cumulated dataset, which represents a sum of the autocorrelation functions which correspond with the first datasets. Finally, a representation of a particle size distribution is determined by solving this representation from an expression for the second, cumulated dataset in terms of the representation of a particle size distribution.