A storage vessel is provided to reduce evaporation of volatile substances such as matrix solution used for preparing samples originating from electrophoresis gel slabs for mass spectrometry. Characteristic to the method in accordance with the invention is the fact that a digital image formedproduced with a camera andor a display device is corrected by means of a database formed from the spectrum information of colour references. The reflecting layer provides reflecting means for the light emitting elements, improving utilization of the light emitting from the light emitting elements, and thus increasing the luminance of the illumination module of light emitting elements. Thus, information exchange and fostering of human relations are supported in the real world through the virtual world. The anvil is serrated to provide sloping supporting surfaces and buttress surfaces against which the yarn is pressed by the yarns as the horn passes over each yarn. Thus, the image processing device of the invention increases the speed of generating coded data, and enhances the total throughput.