fig1 schematically illustrates a laser processing apparatus 1 for processing an object 2 . the laser processing apparatus comprises a control device 3 , which controls firstly a pulsed laser 4 and secondly a beam guiding device 5 . the beam guiding device 5 guides a laser beam 6 of the pulsed laser 4 onto a position of the object 2 in a targeted manner . a processing or marking of the object 2 is performed in accordance with processing information 7 . in the example illustrated in a simplified fashion , the processing information represents a pixelated line , that is to say a line decomposed into pixels . in the example illustrated , the positions on the object 2 which are assigned to the pixels are intended either to remain unmarked , which is symbolized by a “−”, or to be blackened , which is identified by an “ s ”. if the object is processed at a position with a laser pulse having a pulse energy below a minimum energy threshold , then generally no material change occurs . in order to achieve blackening , a maximum pulse energy is required in accordance with the design of the pulsed laser described here . for the person skilled in the art , it goes without saying that pulsed lasers exist whose laser pulses can achieve sufficient desired blackening using a single laser pulse , even if the pulsed laser is not operated with the maximum possible pulse energy . hereinafter it is assumed in each case that the pulsed laser is chosen and dimensioned such that a maximum pulse energy brings about optimum blackening of the object , but does not cause disruption over and above that , or a marking of adjacent locations representing other pixels is impaired . in the optimum case , the laser pulses of the laser radiation which impinge on locations which are not intended to be marked have a pulse energy of 0 . this is tantamount to the fact that the laser emits no pulse . hereinafter , no distinction will be made in this respect as to whether no laser pulse or a laser pulse having an energy below the minimum energy threshold is generated . in both cases , mention will be made of laser pulses having a pulse energy of 0 . they are understood to mean laser pulses that are not really generated and such laser pulses which do not have a sufficient energy to effect a material change from the object . the pulsed laser 4 has an energy control input 8 to which can be applied an analog signal , the voltage of which controls a laser pulse energy . the greater the applied voltage , the greater the pulse energy output by the laser . in addition , the pulsed laser 4 has a retrieval input 9 for receiving a signal by means of which a retrieval of the laser pulses is controllable temporally . in order to perform this energy control , the control device 3 generates a pulse energy signal 10 on the basis of processing information 7 , the voltage profile of said pulse energy signal being graphically plotted schematically . the voltage 12 is plotted against the time 13 . the pulse energy signal 10 is generated in a manner temporally correlated with a clock signal 14 having short clock pulses 15 , which are often also designated as trigger pulses , at equidistant time intervals , as is indicated in the schematic graphical representation 16 . the voltage is again plotted against the time . the pulse energy signal 10 is connected to the energy control input and the clock signal 14 is connected to the retrieval input 9 of the pulsed laser 4 . the pulse energy signal 10 has a minimum voltage at times which correspond to clock pulses 15 - 1 , 15 - 4 to 15 - 6 , 15 - 8 and 15 - 9 of the clock signal 14 which retrieve laser pulses 19 - 1 , 19 - 4 to 19 - 6 , 19 - 8 and 19 - 9 which are passed via the beam guiding device 5 to locations of the object 2 which are not intended to be marked . correspondingly the pulse energy signal 10 has a maximum voltage at those times which correspond to clock pulses 15 - 2 , 15 - 3 , 15 - 7 , 15 - 10 to 15 - 14 of the clock signal 14 which retrieve laser pulses 19 - 2 , 19 - 3 , 19 - 7 , 19 - 10 to 19 - 14 , which are passed to locations at which the object 2 is intended to be marked , i . e . blackened . it is evident that the control of the beam guiding device 5 in a manner adapted to the clock signal 14 , i . e . in a manner temporally correlated with said clock signal , is effected by means of a control signal 17 generated by the control device 3 . the beam guiding device 5 preferably comprises a galvanometer 18 for bringing about the beam guiding of the laser beam 6 . since the pulsed laser 4 has a low - pass filter characteristic , the generated laser pulses 19 - 2 , 19 - 3 , 19 - 7 , 19 - 10 to 19 - 14 which are intended to bring about blackening do not all have the maximum laser energy required for this purpose . as is evident from the schematic graphical representation 20 , in which a pulse energy 21 is plotted against the time 13 . it can be discerned that the pulse energy of the individual laser pulses 19 after a change in the voltage of the pulse energy signal from 0 to the maximum value , for example , 10 v , increases only step by step . it is not until after approximately 3 to 5 temporally directly successive laser pulses 19 with a required maximum pulse energy that this maximum pulse energy is also actually achieved . as a result , this is manifested by the fact that a series of pixels 22 - 1 to 22 - 14 have different gray - scale values , but are not black . in particular , a pixel 22 - 7 whose adjacent pixels 22 - 6 , 22 - 8 are not marked ( and are not intended to be marked either ) has only a light gray shade . this is unsatisfactory since a contrast is insufficient . fig2 schematically illustrates an embodiment of a laser processing apparatus 31 with which a marking of an object 2 configured as a document is performed on the basis of the same processing information 7 . identical or identically acting technical features are identified by the same reference signs in all of the figures . as in the case of the laser processing apparatus 1 according to the prior art , shown in fig1 , the pulsed laser 4 having the energy control input 8 and the retrieval input 9 generates a laser beam 6 composed of individual laser pulses 19 . the laser beam 6 is guided by the beam guiding device 5 , which preferably comprises a galvanometer 18 for this purpose . as in the case of the embodiment according to the prior art , the control device 31 generates a pulse energy signal 10 on the basis of the processing information , the voltage profile 11 of said pulse energy signal being identical to that generated by the control device 3 according to the prior art . in the case of the embodiment of a laser processing apparatus 30 according to fig2 , the pulse energy signal 10 and the clock signal 11 are not passed directly to the energy control input 8 and the retrieval input 9 of the pulsed laser 4 . however , a filter device 32 is provided between the control device 31 and the laser 4 . the filter device 32 comprises a pulse energy input 33 for receiving the pulse energy signal 10 . in addition , the filter device 32 comprises a clock signal input 34 for receiving the clock signal 14 . a voltage of the pulse energy signal 10 is compared with a threshold value condition 36 in a comparator device 35 . the result of the comparison is represented by means of a logic result signal 37 . by means of a graphical representation 43 , the comparison result is plotted against the time 13 , by way of example . in one embodiment , the result signal 37 assumes the logic value true if the threshold value condition is met , and otherwise the value false . since a threshold value condition can also be formulated in a logically negated manner , the choice can be oppositely made in other embodiments . a threshold value condition can be formulated for example as follows : “ is the voltage of the pulse energy signal greater than a lower limit threshold value ?”. alternatively , the threshold value condition could be formulated as follows : “ does the voltage of the pulse energy signal fall below the lower limit threshold value ?”. depending on the choice of threshold value condition , the latter would therefore be met or not met for a given voltage value of the pulse energy signal . it is assumed hereinafter , however , that the logic result signal 37 assumes the value true if the threshold value condition 36 is met , and otherwise the value false . in general , the logic signal true is associated with one voltage level and the value false is associated with another voltage level , for example 0 v . the clock signal 14 is passed to a gate 38 , which is controlled by the logic result signal 37 . if the logic result signal has the value true , then the clock signal 14 is conducted through the gate 38 and a retrieval signal 39 is thus generated , which comprises retrieval pulses 45 corresponding to those of the clock signal . if the logic result signal has the value false , the gate effects blocking and the retrieval signal 39 has a predefined value , for example a voltage of 0 v . the gate 38 can be realized by a gate circuit designed , for example , as an and circuit . the retrieval signal 39 is output at a retrieval signal output 48 . it should be noted at this juncture that an optical signal can also be used as the clock signal 14 . the clock pulses 15 then correspond to light pulses , for example . it is important to emphasize that the retrieval signal 39 comprises retrieval pulses 45 - 2 , 45 - 3 , 45 - 7 , 45 - 10 to 45 - 14 , which correspond to those clock pulses 15 - 2 , 15 - 3 , 15 - 7 , 15 - 10 to 15 - 14 which are in turn temporally assigned to a voltage of the pulse energy signal which meets the threshold value condition . the remaining clock pulses 15 - 1 , 15 - 4 to 15 - 6 , 15 - 8 , 15 - 9 of the clock signal 14 are as it were “ removed ” and are not contained in the retrieval signal 19 , as is indicated graphically . clock pulses 15 - 1 , 15 - 4 to 15 - 6 , 15 - 8 , 15 - 9 which are to be assigned to voltage values of the pulse energy signal 10 which do not meet the threshold value condition are therefore blocked by the gate 38 and not forwarded . for these clock pulses 15 - 1 , 15 - 4 to 15 - 6 , 15 - 8 , 15 - 9 there are no counterparts in the retrieval signal 39 . furthermore , the filter device 32 has a voltage source 40 , which generates an energy control signal 41 that is stabilized with regard to the voltage . preferably , the voltage source is adjustable , such that the voltage of the energy control signal 41 is generated in accordance with a predefinition for a control voltage . via an interface 42 the filter device 31 can receive the predefinition for the control voltage . likewise , the latter can alternatively or additionally be adjustable by means of a mechanical actuator ( not illustrated ) at the filter device 32 . in one embodiment , the threshold value condition 36 can also be detectable via the interface 42 . in one embodiment the comparator device 35 is designed to evaluate threshold value conditions which comprises a lower limit threshold value . for this purpose , the comparator device 35 has to have a comparison circuit that compares the voltage with the lower limit threshold value and generates a result signal having the value true if the voltage of the pulse energy signal 10 exceeds the lower limit threshold value . in another embodiment the comparator device is designed such that it can evaluate threshold value conditions comprising a predefined voltage range . the latter can be specified by a lower limit threshold value and by an upper limit threshold value . further configurations that specify a limit threshold value and an interval voltage are also possible . in this other embodiment , the comparator device 35 comprises for example two comparator circuits that compare the voltage of the pulse energy signal with the limit threshold values . the result signal 37 is set to the value true if the voltage lies above the lower limit threshold value and below the upper limit threshold value and is otherwise set to the value false . this embodiment makes it possible to perform processing steps with a predefined pulse energy which , in accordance with the processing information , should be performed with pulse energies lying in the range represented by the predefined voltage range . in order nevertheless to be able to perform processing steps with variable pulse energies , for example to mark ( to produce ) a gray - scale image , the filter device 31 according to fig2 has a changeover device 44 . in one switching state , designated as a filter state , the pulse energy signal is fed to the comparator device and the clock signal is fed to the gate 38 and the energy control signal 41 is generated by the voltage source 40 and output . consequently , the voltage source is connected to the energy control signal output 46 . in this state , high - contrast ( black - and - white ) information , for example a microscript , can be marked ( produced ). in a further switching state , called bypass state , the pulse energy signal 10 is connected to the energy control signal output 46 , such that the energy control signal 41 is supplied by the pulse energy signal . furthermore , the clock signal 14 is passed directly as the retrieval signal 39 to a retrieval signal output 48 or the gate 38 is put into that state such that each clock pulse 15 generates a retrieval pulse 45 . it is possible for the pulse energy signal 10 and / or the clock signal 14 to be passed via a delay circuit 47 in order to obtain a temporal adaptation to the signal processing durations which occur in the filter state , in order to maintain an adaptation to the beam guiding by the beam guiding device 5 . in one embodiment , the control device 31 has an information filter device 51 , which subjects the processing information to high - pass filtering and thus generates edge processing information 52 . for each processing location of the object to be processed , there is now processing information specifying a pulse energy for a processing step at this location , and edge processing information containing an indication about the extent to which the pulse energy , in accordance with the processing information , deviates from the pulse energy of the preceding adjacent location to be processed on the object . if the pulse energy increases from one location to the next , then the latter has a high value in the edge processing information . the edge processing information contains information as to how a “ contrast edge ”, a change from light to dark in the generated information , can be reworked . if the processing information 7 is then used to mark the object in the bypass state of the changeover device 44 in the filter device 31 , then a gray - scale imaging is marked , for example , the edges of which are washed out and have low contrast on account of the low - pass filter property of the pulsed laser 4 , as explained in connection with the embodiment according to fig1 . afterward , with identical renewed driving of the beam guiding device 5 , renewed processing of the object is performed wherein the edge processing information 52 is used for generating the pulse energy signal 10 and the filter device 31 with the changeover device 44 is operated in the filter state . the threshold value condition 36 is set such that only locations are marked at which an abrupt change in the processing energy occurs in the processing information , and the edge processing information thus has high values . the voltage of the energy control signal 41 generated by the voltage source 40 can be chosen to be moderate in many cases , since a partial blackening was already effected in the first processing step . the marking or processing in accordance with the edge processing information is thus effected congruently with the processing in accordance with the processing information 7 and provides for contrast improvement . it goes without saying that this post - processing can be restricted to a portion of the processing information , representing for example a historical image . likewise , a changeover between the filter state and the bypass state can also be effected without post - processing during the processing of the processing information , in order to mark different portions of the processing information in accordance with the different advantages of the changeover states . gray shades can be generated in the bypass state ; high - contrast and locally highly resolved fine structures can be marked in the filter state . for the person skilled in the art it goes without saying that only exemplary embodiments have been described . in particular , the described processing method and the laser processing apparatus and the filter device are particularly suitable for marking individualizing and / or personalizing information into an object embodied as a security document .