Abstract: The invention relates to a method for encoding items of information and to a device and method for evaluating the encoded information. A prior art method for marking and providing objects with items of information and data involves the creation and use of bar code. With the inventive method, it is now possible to provide objects with a more sophisticated and higher data density than that provided by prior art methods. By using fluorescent dyes, an additional encoding word is added to the coding language, this coding language having been available up to now and being composed of a sequence consisting of black and white bars, thereby increasing the depictable data density. The inventive device enables the decryption of encrypted and compressed items of information, which have a higher data density than that of prior art encoding methods. To this end, an opto-electrical reading unit is equipped with means that control the emission of light.

Abstract: A method and probe for detecting the concentration of a substance in a measurement region in a subsurface exploration wherein the electromagnetic energy is delivered to this region and picked up from this region via an optical fiber and the measurement is taken or the electromagnetic energy is supplied at a number of locations within the region.

Abstract: A method and probe for subterranean determination of the concentration of a substance has a light-conducting optical fiber running from above the ground to a measurement cell below the ground. The system can be used effectively for fluorescent markers to track the ground water flow.