Abstract: A method for assessing the condition and improving the printing quality of printing nozzles in printheads of an inkjet printing machine includes printing a nozzle test chart formed of a specific number of horizontal rows of equidistant vertical lines printed periodically underneath one another, with only every nth printing nozzle contributing to the test chart in every row of the test chart and n corresponding to a different number between one and the specific number of horizontal rows, recording and digitizing the test chart and analyzing the test chart regarding the condition of the contributing nozzles by using a computer. The nozzles printing horizontal lines between the horizontal rows complementing the equidistant vertical lines to form quadrangular objects used by the computer to analyze the condition of the contributing nozzles. Measures are taken to improve the printing quality of the nozzles depending on the condition of the contributing nozzles.

Abstract: A method compensates for position-dependent density fluctuations of print nozzles in an inkjet printing machine by use of a computer. The computer produces compensation profiles for the position-dependent density fluctuations over all the print heads for all print substrates used, calculates an mean profile from these, and applies the mean profile to compensate for the position-dependent density fluctuations in the inkjet printing machine. When one or more print heads of the inkjet printing machine are replaced, the computer calculates a new compensation profile for only one print substrate. The computer derives a new mean profile from this, and the computer calculates and applies the new mean profile using the old compensation profiles for the remaining print substrates.

Abstract: A method for assessing the condition and improving the printing quality of printing nozzles in printheads of an inkjet printing machine includes printing a nozzle test chart formed of a specific number of horizontal rows of equidistant vertical lines printed periodically underneath one another, with only every nth printing nozzle contributing to the test chart in every row of the test chart and n corresponding to a different number between one and the specific number of horizontal rows, recording and digitizing the test chart and analyzing the test chart regarding the condition of the contributing nozzles by using a computer. The nozzles printing horizontal lines between the horizontal rows complementing the equidistant vertical lines to form quadrangular objects used by the computer to analyze the condition of the contributing nozzles. Measures are taken to improve the printing quality of the nozzles depending on the condition of the contributing nozzles.

Abstract: A method detects defective printing nozzles in an inkjet printing machine having a computer. The method includes printing a multi-row nozzle test chart for detection purposes, the test chart contains a number of horizontal rows of equidistant vertical lines printed periodically and disposed underneath one another. Wherein in every row of the nozzle test chart periodically only those respective printing nozzles of the print head contribute to the first element of the nozzle test chart that correspond to the specified number of the horizontal rows. An area coverage element geometrically associated with the nozzle test chart is printed. Both elements are recorded by an image sensor and both elements are evaluated by the computer. Defective printing nozzles are identified by evaluating the recorded nozzle test chart by the computer. Defects are allocated in the area coverage element to the printing nozzles in the nozzle test chart by the computer.

Abstract: A method for detecting defective printing nozzles in an inkjet printing machine includes printing a multi-row printing nozzle test chart formed of horizontal rows of equidistant vertical lines periodically underneath one another, with only printing nozzles in a print head contributing to every row of the test chart corresponding to the horizontal rows. An area coverage element geometrically associated with the test chart is printed, both elements are recorded by an image sensor and analyzed by the computer. The computer analyzes the recorded area coverage element to detect print defects and allocates defects to a region of geometrically close printing nozzles. An analysis of the test chart in the region identifies nozzles causing the defect. Defective printing nozzles are detected based on thresholds, the detected printing nozzles are then compensated, and in the analysis of the recorded area coverage element, influences of the sensor are eliminated by shading correction.

Abstract: A method compensates for position-dependent density fluctuations of print nozzles in an inkjet printing machine by use of a computer. The computer produces compensation profiles for the position-dependent density fluctuations over all the print heads for all print substrates used, calculates an mean profile from these, and applies the mean profile to compensate for the position-dependent density fluctuations in the inkjet printing machine. When one or more print heads of the inkjet printing machine are replaced, the computer calculates a new compensation profile for only one print substrate. The computer derives a new mean profile from this, and the computer calculates and applies the new mean profile using the old compensation profiles for the remaining print substrates.

Abstract: A method for detecting defective printing nozzles in an inkjet printing machine includes printing a multi-row printing nozzle test chart formed of horizontal rows of equidistant vertical lines periodically underneath one another, with only printing nozzles in a print head contributing to every row of the test chart corresponding to the horizontal rows. An area coverage element geometrically associated with the test chart is printed, both elements are recorded by an image sensor and analyzed by the computer. The computer analyzes the recorded area coverage element to detect print defects and allocates defects to a region of geometrically close printing nozzles. An analysis of the test chart in the region identifies nozzles causing the defect. Defective printing nozzles are detected based on thresholds, the detected printing nozzles are then compensated, and in the analysis of the recorded area coverage element, influences of the sensor are eliminated by shading correction.

Abstract: A method detects defective printing nozzles in an inkjet printing machine having a computer. The method includes printing a multi-row nozzle test chart for detection purposes, the test chart contains a number of horizontal rows of equidistant vertical lines printed periodically and disposed underneath one another. Wherein in every row of the nozzle test chart periodically only those respective printing nozzles of the print head contribute to the first element of the nozzle test chart that correspond to the specified number of the horizontal rows. An area coverage element geometrically associated with the nozzle test chart is printed. Both elements are recorded by an image sensor and both elements are evaluated by the computer. Defective printing nozzles are identified by evaluating the recorded nozzle test chart by the computer. Defects are allocated in the area coverage element to the printing nozzles in the nozzle test chart by the computer.

Abstract: A method for detecting and compensating for failed printing nozzles in an inkjet printing machine by using a computer, includes printing a current print image, recording the printed print image by using an image sensor and digitizing the recorded print image by using the computer, adding digitized color values of the recorded print image of every column over the entire print image height and dividing the added-up color values by the number of pixels to obtain a column profile, subtracting an optimized column profile without failed printing nozzles from the original column profile to obtain a differential column profile, setting a maximum value threshold defining a failed printing nozzle when exceeded, applying that maximum value threshold to the differential column profile to obtain a resultant column profile every maximum of which marks a failed printing nozzle. The marked printing nozzles are compensated in a subsequent printing operation.

Abstract: A method for compensating for failed printing nozzles in an inkjet printing machine uses a computer to provide an increased ink drop volume of adjacent nozzles. All existing printing nozzles are measured regarding print failure and deviation of a printed dot beyond a specific threshold, so that the printing nozzles are marked either as functioning, failed, or printing a dot deviating in a direction transverse to the printing direction, and the results are saved on the computer. The computer hides all functioning printing nozzles and marks all remaining isolated printing nozzles as failed nozzles. The computer groups adjacent remaining printing nozzles by marking nozzles printing a dot deviating in a direction transverse to the printing direction as functioning printing nozzles contributing to the compensation or as failed printing nozzles in accordance with a rule, and the computer compensates for all printing nozzles having been marked as failed.

Abstract: A method for detecting and compensating for failed printing nozzles in an inkjet printing machine by using a computer, includes printing a current print image, recording the printed print image by using an image sensor and digitizing the recorded print image by using the computer, adding digitized color values of the recorded print image of every column over the entire print image height and dividing the added-up color values by the number of pixels to obtain a column profile, subtracting an optimized column profile without failed printing nozzles from the original column profile to obtain a differential column profile, setting a maximum value threshold defining a failed printing nozzle when exceeded, applying that maximum value threshold to the differential column profile to obtain a resultant column profile every maximum of which marks a failed printing nozzle. The marked printing nozzles are compensated in a subsequent printing operation.

Abstract: A method for compensating for failed printing nozzles in an inkjet printing machine uses a computer to provide an increased ink drop volume of adjacent nozzles. All existing printing nozzles are measured regarding print failure and deviation of a printed dot beyond a specific threshold, so that the printing nozzles are marked either as functioning, failed, or printing a dot deviating in a direction transverse to the printing direction, and the results are saved on the computer. The computer hides all functioning printing nozzles and marks all remaining isolated printing nozzles as failed nozzles. The computer groups adjacent remaining printing nozzles by marking nozzles printing a dot deviating in a direction transverse to the printing direction as functioning printing nozzles contributing to the compensation or as failed printing nozzles in accordance with a rule, and the computer compensates for all printing nozzles having been marked as failed.

Abstract: A method for automated detection of failed printing nozzles in an inkjet printing machine includes the following steps: carrying out a printing process to produce a first printed image with print image data, scanning and digitizing the first printed image produced in the printing process by using at least one image sensor, digitally offsetting the first printed image in the control unit by at least one printing nozzle in a direction transverse to the printing direction, carrying out a further printing process to produce a second printed image based on the digitally offset first printed image, scanning and digitizing the second printed image by using the at least one image sensor, comparing the first and second scanned printed images in the control unit. Failed printing nozzles are identified by using the control unit based on the result of the comparison.

Abstract: A method for automated detection of failed printing nozzles in an inkjet printing machine includes the following steps: carrying out a printing process to produce a first printed image with print image data, scanning and digitizing the first printed image produced in the printing process by using at least one image sensor, digitally offsetting the first printed image in the control unit by at least one printing nozzle in a direction transverse to the printing direction, carrying out a further printing process to produce a second printed image based on the digitally offset first printed image, scanning and digitizing the second printed image by using the at least one image sensor, comparing the first and second scanned printed images in the control unit. Failed printing nozzles are identified by using the control unit based on the result of the comparison.

Abstract: A method for compensating failed printing nozzles in inkjet printing machines using a control computer, includes printing a test form for a material combination, evaluating the print and creating a look-up table having compensation probabilities for local surface density, detecting a failed nozzle, reading the size of the intended droplet to be compensated at the failed nozzle, calculating local surface density at the failed nozzle, reading a compensation probability from the table with the calculated local surface density, calculating a pseudo-random number for adjacent pixels right and left of the pixel to be compensated, increasing the droplet size for adjacent pixels if the pseudo-random number therefor is lower than the compensation probability from the table, calculating adjacent droplet sizes for all intended droplets at the failed nozzle and using the changed droplet sizes in printing data. The print job is carried out with changed printing data.

Abstract: A method for compensating failed printing nozzles in inkjet printing machines using a control computer, includes printing a test form for a material combination, evaluating the print and creating a look-up table having compensation probabilities for local surface density, detecting a failed nozzle, reading the size of the intended droplet to be compensated at the failed nozzle, calculating local surface density at the failed nozzle, reading a compensation probability from the table with the calculated local surface density, calculating a pseudo-random number for adjacent pixels right and left of the pixel to be compensated, increasing the droplet size for adjacent pixels if the pseudo-random number therefor is lower than the compensation probability from the table, calculating adjacent droplet sizes for all intended droplets at the failed nozzle and using the changed droplet sizes in printing data. The print job is carried out with changed printing data.

Abstract: The invention relates to a device for measuring at least one parameter of an arterial blood sample, including a flow sensor having standardized connecting elements which are connected to the inlet and the outlet side of a measuring cell of the flow sensor, the measuring cell having at least one optochemical sensor element which can be brought in contact with the blood sample. A connector is removably placed on the flow sensor and includes at least one light source for exciting the optochemical sensor element and at least one photodetector for receiving the measurement radiation of the optochemical sensor element. An electronic module has an electric connecting line to the connector and contacts the at least one light source and the at least one photodetector, the flow sensor being connectible to the standardized connection of an arterial catheter via the connecting element on the inlet side and to the standardized connection of an arterial infusion set via the connection on the outlet side.

Abstract: Measuring devices are disclosed for determination of at least one parameter of a blood sample. The measuring device includes a flow-through measuring cell, in which is disposed luminescence-optical sensor elements, which can be brought into contact with the blood sample, and at least one light source for excitation of the luminescence-optical sensor element and at least one photodetector for receiving the luminescence radiation emitted by the luminescence-optical sensor element. The light source and the photodetector are located on opposite sides of the flow-through measuring cell. The sensor elements are placed on an excitation side of the flow-through measuring cell, which faces the light source, and the light source emits excitation radiation of wavelength less than 600 nm, while the luminescence radiation of the sensor elements lies in a wavelength range greater than 600 nm, thus exposing the excitation radiation to stronger absorption by the blood sample than the luminescence radiation.

Abstract: A device for monitoring a parameter of a fluidic sample by microdialysis, the device comprising a permeable membrane, wherein the permeable membrane has a first surface to be brought in contact with the fluidic sample to traverse the permeable membrane (300), wherein the permeable membrane has a second surface to be brought in contact with a dialysis fluid, and wherein the first surface is smoother than the second surface.

Abstract: Measuring devices are disclosed for determination of at least one parameter of a blood sample. The measuring device includes a flow-through measuring cell, in which is disposed luminescence-optical sensor elements, which can be brought into contact with the blood sample, and at least one light source for excitation of the luminescence-optical sensor element and at least one photodetector for receiving the luminescence radiation emitted by the luminescence-optical sensor element. The light source and the photodetector are located on opposite sides of the flow-through measuring cell. The sensor elements are placed on an excitation side of the flow-through measuring cell, which faces the light source, and the light source emits excitation radiation of wavelength less than 600 nm, while the luminescence radiation of the sensor elements lies in a wavelength range greater than 600 nm, thus exposing the excitation radiation to stronger absorption by the blood sample than the luminescence radiation.