Abstract: A flow system, preferably a micro fluidic system, having a base part (4) with at least one flow path formed therein and a lid part (5) being attached to the base part (4) in such a manner that it covers the flow path(s). The flow path(s) comprise(s) a flow restrictor (1) and a flow channel comprising an inlet section positioned immediately upstream relatively to the flow restrictor (1). At least the inlet section of the flow channel has a cross section defining at least two distinct depths of the flow channel. This may be achieved by defining a centre section (3) and at least one peripheral section (2), the centre section (3) having a depth and a width which are substantially larger than the depth(s) and width(s) of the peripheral section(s) (2). If air bubbles are formed in the system this design of the inlet section will allow a flow of liquid to enter the shallower parts of the flow channel, while the air bubbles are confined to the deeper parts of the flow channel.

Abstract: A flow system (1) comprising a first part (2) and a second part (3), the parts (2, 3) being made from materials having different coefficients of thermal expansion. The first (2) and second (3) parts are positioned relatively to each other in such a way that when the ambient temperature changes corresponding changes are caused in a flow channel (4) formed in the first part (2), thereby changing the flow resistance of the flow channel (4). Thereby a change in flow resistance caused by a change in viscosity of a fluid being transported by the flow system (1) can be counteracted. The resulting flow resistance of the flow system (1) is thereby at least substantially independent of the ambient temperature. Furthermore, a micro fluidic system comprising the flow system (1). The micro fluidic system may be or form part of a medical device, a fluid analysis system, e.g. a device for measuring blood glucose levels of blood samples, or an infusion device.

Abstract: A method and device are provided for the determination of the concentration of compounds in body tissue. The method utilises optical methods based on the interaction of light with compounds, whereby the concentration of the compound under analysis is determined. The method is especially suited for analysis for the concentration of glucose in blood or tissue of diabetic patients, a device being implanted underneath the skin of the patient and the method being carried out by using the implanted device. The device contains photo detectors at different levels connected by wires to an electronic circuit device. A differential analysis is performed on the signals from the detectors to reduce the effect of skin on the analysis.