Abstract: A process for mixing a liquid sample to be analyzed with periodic air movements includes the steps of placing the sample in a sample container and alternately directing air jets onto different regions of the surface of the sample, wherein the air jets displace the surface regions and produce turbulence in the sample. An apparatus is provided for practicing the process.

Abstract: The invention relates to a device for producing images of a layer of a three-dimensional object, with radiation sources arranged in a radiation source plane, for irradiating the object with beams of rays from different directions, and with several planar recording layers, arranged parallel to one another, of recording all said shadow images, wherein before each recording layer there is arranged a diaphragm arrangement that has been allocated to it for (stepwise) masking of the beams of rays, and wherein the diaphragm apertures of each diaphragm arrangement are so much the smaller, the greater the distance the diaphragm arrangement is from the radiation sources.

Abstract: A device for imaging layers of the interior of a three-dimensional object. The object is irradiated from a large number of radiation source positions which are distributed in one plane from this, a coded image of the object which coded image consists of separate perspective images is produced. The coded image is illuminated and imaged by means of an imaging matrix whose imaging elements are distributed in the matrix plane according to the flat distribution of the radiation source positions. Layer images of the object are formed on a photosensitive element by the superposition of the perspective images. For forming different layer images of the object, the imaging elements are positioned in different distributions of changed scale with respect to the distribution of the radiation source positions.

Abstract: For the formation of layer images of a three-dimensional object, the object is irradiated from a large number of radiation source positions which are situated in one plane. Thus, a coded image of the object, consisting of individual perspective images, is formed. Subsequently, the coded image is illuminated and the perspective images thereof are superposed for the reconstruction of the object by means of a lens matrix which extends parallel to the plane of the coded image and whose flat lens distribution corresponds to the distribution of the radiation source positions. In the superposition zone of the perspective images, a photosensitive element is introduced in order to form individual layer images of the object. For the formation of the different layer images on the photosensitive element, the lens matrix is displaced in the direction of the optical axis, and the photosensitive element is positioned each time within the depth of focus range of the lenses of the lens matrix.