Recurrence rate controller.

1. Technical area of the invention the available invention concerns the regulation of the recurrence rate of a laser light pulse. 2. Associated conditions of the technology a system, which keeps a difference in the recurrence rate between two lasers constant by independent regulating of the recurrence rates of the two lasers, are generally admit (e.g. see Fig. 18 and a patent document 1 (JP 456,198)). SUMMARY of the INVENTION it is to be changed a task of the available invention a difference in the recurrence rate between two lasers. A recurrence rate controller in accordance with the available invention covers: a master laser, which spends a master laser light pulse, whose recurrence rate is regulated to a before specified value; a Slave laser, which spends a Slave Laserlichtpuls; a reference comparator, which compares a tension of an electrical reference signal and a before specified tension with one another, whereby the recurrence rate of the electrical reference signal is the before specified value, and a result of the comparison spends; a measuring comparator, which compares a tension with one another based on a light intensity of the Slave Laserlichtpulses and the before specified tension and spends a result of the comparison; a phase difference detector, which detects a phase difference between the expenditure of the reference comparator and the expenditure of the measuring comparator; a loop filter, which removes a high frequency component of an expenditure of the phase difference detector; and an adder, which adds a recurrence rate rule signal to an expenditure of the loop filter, how: the recurrence rate rule signal a constant Widerholungszyklus possesses; and the recurrence rate of the Slave Laserlichtpulses in accordance with the expenditure of the adder changes. A master laser in accordance with in such a way developed recurrence rate controller spends a matte laser light pulse, whose recurrence rate is regulated to a before specified value. A Slave laser spends a Slave Laserlichtpuls. A reference comparator compares a tension of an electrical reference signal and a before specified tension with one another, whereby the recurrence rate of the electrical reference signal is the before specified value, and spends a result of the comparison. A measuring comparator compares a tension based on a light intensity of the Slave Laserlichtpulses and the before specified tension with one another and spends a result of the comparison. A phase difference detector detects a phase difference between the expenditure of the reference comparator and the expenditure of the measuring comparator. A loop filter removes a high frequency component of an expenditure of the phase difference detector. An adder adds a recurrence rate rule signal to an expenditure of the loop filter. The recurrence rate rule signal possesses a constant repetition cycle. The recurrence rate of the Slave Laserlichtpulses changes in accordance with the expenditure of the adder. The before specified tension in accordance with the recurrence rate controller of the available invention can be an electrical grounding potential. The resonator length of the Slave laser in accordance with the recurrence rate controller of the available invention can change in accordance with the expenditure of the adder. The Slave laser in accordance with the recurrence rate controller of the available invention can cover an Piezo element; the expenditure of the adder can be supplied to the Piezo element; and the resonator length of the Slave laser can be changed by expansion and contraction of the Piezo element. The recurrence rate controller in accordance with the available invention can cover: photoelectric conversion unit, which receives the Slave Laserlichtpuls; and a low-pass filter, which removes a high frequency component of the expenditure of the photoelectric conversion unit. The recurrence rate rule signal in accordance with the recurrence rate controller of the available invention can be spent by a user defining wave generator (arbitrary wave generator). The recurrence rate controller in accordance with the available invention can cover: a master-lateral reference comparator, which compares the tension of the electrical reference signal and the before specified tension with one another, whereby the frequency of the electrical reference signal is the before specified value, and a signal of the comparison spends; a master-lateral measuring comparator, which a tension of an electrical master-lateral measuring signal, which possesses a tension based on a light intensity of the master laser light pulse and a frequency of the before specified value, and which compare fixed tension with one another before and spend a result of the comparison; a master-lateral phase difference detector, which detects a phase difference between the expenditure of the master-lateral reference comparator and the expenditure of the master-lateral measuring comparator; and a master-lateral loop filter, which removes a high frequency component of an expenditure of the master-lateral phase difference detector, whereby the recurrence rate of the master laser light pulse changes in accordance with an expenditure of the master-lateral loop filter. SHORT DESCRIPTION of the FIGURES Fig. 1 is a functional module diagram, which shows a configuration of a recurrence rate controller I in accordance with the execution form of the available invention; Fig. a diagram, which shows a wave shape of an expenditure tension of a measuring comparator 115, covers 2 (Fig. 2 (A)) and a diagram, which a wave shape of an expenditure tension of a reference comparator 122 (Fig. 2 (B)) in accordance with the execution form of the available invention shows; Fig. the expenditure of the recurrence rate rule signal source 238 (Fig shows 3. 3 (A)), the expenditure of the adder 235 (Fig. 3 (B)), the recurrence rate of the Slave laser 212 (Fig. 3 (C)) and the recurrence rate of the master laser 112 (Fig. 3 (D)); and Fig. a modification shows and shows 4 in the expenditure of the recurrence rate rule signal the expenditure of the recurrence rate rule signal source 238 (Fig. 4 (A)), the expenditure of the adder 235 (Fig. 4 (B)), the recurrence rate of the Slave laser 212 (Fig. 4 (C)) and the recurrence rate of the master laser 112 (Fig. 4 (D)). PREFERENTIAL EXECUTION FORMS now a description of an execution form of the available invention given with reference to the figures. Fig. 1 is a functional module diagram, which shows a configuration of a recurrence rate controller 1 in accordance with the execution form of the available invention. Fig. a diagram, which a wave shape of an expenditure tension of a measuring comparator, covers 2 115 (Fig. ) and a diagram, which shows a wave shape of an expenditure tension of a reference comparator 122, shows 2 (A) (Fig. 2 (B)) in accordance with the execution form of the available invention. A recurrence rate controller 1 in accordance with the execution form of the available invention covers a master laser 112, an optical coupler 114, the measuring comparator (master-lateral measuring comparator) 115, a photodiode (master-lateral photoelectric conversion unit) 116, a low-pass filter 117, an amplifier 118, an electrical reference signal source 121, the reference comparator (master-lateral reference comparator) 122, a phase comparator (master-lateral phase difference detector) 132, a loop filter (master-lateral loop filter) 134, a Piezo driver 136, a Slave laser 212, an optical coupler 214, a measuring comparator 215, a photodiode (photoelectric conversion unit) 216, a low-pass filter 217, an amplifier 218, a reference comparator 222, a phase comparator (phase difference detector) 232, a loop filter 234, an adder 235, a Piezo driver 236 and a recurrence rate rule signal source 238. The master laser 112 spends a master light pulse. It is to be marked that the recurrence rate of the master laser light pulse is regular to a before specified value. The before specified value is equal to the frequency (e.g. 50 MHz) of an electrical reference signal, which by the electrical reference signal source 121 one spends. The master laser 112 covers an Piezo element 112p. The Piezo element 112p expands and contracts in a X-direction (horizontal direction in Fig. 1) as a result of a creation of a tension of an expenditure of the loop filter 134 after a reinforcement by the Piezo driver 136. The expansion/contraction in the X-direction of the Piezo element 112p changes a laser resonator length of the master laser 112. The change of the laser resonator length changes the recurrence rate of the master laser light pulse. The optical coupler 114 receives the master laser light pulse, which by the master laser 112 one spent and to the photodiode gives the master laser light pulse to 116 and the environment in an energy relationship of e.g. 1:9 off. The optical energy of the master laser light pulse is supplied to the photodiode 116 and is from there e.g. 10% of the optical energy of the master laser light pulse, which by the master laser 112 one spent. The photodiode (master-lateral photoelectric conversion unit) 116 receives the master laser light pulse from the optical coupler 114 and converts the master laser light pulse into an electrical signal. It is to be marked that the recurrence rate of the master laser light pulse on 50 MHz is regulated. As a result the electrical signal possesses a component of the frequency 50 MHz (component of the frequency of the electrical reference signal) and a high frequency component (frequency clearly more highly than 50 MHz). The low-pass filter 117 removes the high frequency component of the expenditure of the photodiode 116. The critical frequency of the low-pass filter 117 is e.g. 70 MHz. Therefore the high frequency component is removed, if the low-pass filter 117 receives the expenditure of the photodiode 116 and the component to the frequency to 50 MHz (component of the frequency of the electrical reference signal) passes. An expression “remove” implied not necessarily only the complete distance and a case, in which the high frequency component remains in small mass, is likewise in the expression “remove” contained. In the following section the expression possesses “removes” the same meaning. The amplifier 118 strengthens the expenditure of the low-pass filter 117. An expenditure of the amplifier 118 is called electrical measuring signal. Attaining the electrical measuring signal corresponds to a measurement of the light intensity of the matte laser light pulse. The master-lateral electrical measuring signal is attained by strengthening the expenditure of the photodiode 116 by the amplifier 118 and possesses from there a tension based on the light intensity of the master laser light pulse. Additionally the master-lateral electrical measuring signal passed and possesses the low-pass filter 117 from there a frequency of the before specified value (frequency of the electrical reference signal). It is conceivable to interconnect the low-pass filter 117 and the amplifier 118 and to supply the expenditure of the photodiode 116 by way of the amplifier 118 the low-pass filter 117. In this case the master-lateral electrical measuring signal is the expenditure of the low-pass filter 117. In each case the master-lateral electrical measuring signal the signal remains based on the expenditure of the low-pass filter 117. The electrical reference signal source 121 spends the electrical reference signal, which possesses a frequency of the before specified value (e.g. 50 MHz). The reference comparator (master-lateral reference comparator) 122 compares the tension of the electrical reference signal and the before specified tension with one another and spends thereby a result of the comparison. It is to be marked that the before specified tension is e.g. the electrical grounding potential. Referring to Fig. 1 possesses the reference comparator 122 two entrance poles: one is connected with the expenditure of the electrical reference signal source 121 and the other one is grounded. The signal output of the reference comparator 122 is determined in accordance with a value difference between the tensions, which rest to entrance Poland of the reference comparator 122 against both. If the tension of the expenditure of the electrical reference signal source is larger 121 than the electrical grounding potential (= o V) takes the tension of the signal, which by the reference comparator 122 one spends e.g. a before specified positive value in accordance with Fig. 2 (B) on. If the tension of the expenditure of the electrical reference signal source 122 lower or equal the electrical grounding potential (= 0 V) is, takes the tension of the signal, which will spend from the reference comparator 122, o V on. The measuring comparator (master-lateral measuring comparator) 115 compares the tension of the master-lateral electrical measuring signal and the before specified tension (like e.g. the electrical grounding potential) with one another and spends a result of the comparison. In other words, the measuring comparator 115 receives the expenditure of the amplifier 118 and the before specified tension, compares both with one another and spends a result of this comparison. If the tension of the expenditure of the amplifier is larger 118 than the electrical grounding potential (=oV), the tension of the signal, which by the measuring comparator 115 one spends, takes e.g. a before specified positive value in accordance with Fig. 2 (A) on. If the tension of the expenditure of the amplifier 118 lower or equal to the electrical grounding potential (- 6V) is, the tension of the signal, which by the measuring comparator 115 one spends, takes the value oV. The phase comparator (master-lateral phase difference detector 132) detects a phase difference between the expenditure of the reference comparator 122 and the expenditure of the measuring comparator 115 and spends this phase difference. The loop filter (master-lateral loop filter) 114 removes a high frequency component of an expenditure of the phase comparator 132. The Piezo driver 136 is e.g. an achievement amplifier and strengthens the expenditure of the loop filter 134. The expenditure of the Piezo driver 136 is supplied to the Piezo element 112p. As a result expanded/the Piezo element 112p in the X-direction contracts. It is to be marked the fact that the Piezo element 112p is expanded in such a way/contracted that the phase difference, which by the phase comparator 132 is detected is a constant value (like e.g. o degrees, 90 degrees or -90 degrees). As a result the recurrence rate of the master laser light pulse can be stopped precisely to the frequency (e.g. 50 MHz) of the electrical reference signal. The Slave laser 212 spends a Slave Laserlichtpuls. The Slave laser 212 covers an Piezo element 212p. The Piezo element 212p expanded/contracts in the XRichtung (horizontal direction in Fig. 1) by the tension of the expenditure of the adder 235, which is strengthened and by the Piezo driver 236 is put on. The expansion/contraction of the Piezo element 212 in the X-direction changes the laser resonator length of the Slave laser 212. The change in the laser resonator length changes the recurrence rate of the Slave Laserlichtpulses. The optical KoppIer 214 is a similar component to the optical coupler 114, receives the Slave Laserlichtpuls, which by the Slave laser 212 one spends, and spends the Slave Laserlichtpuls to the photodiode 216 and the environment in an energy relationship of 1:9. The photodiode (photoelectric conversion unit) 216 is similar a component to the photodiode 116, receives the Slave Laserlichtpuls from the optical coupler 214 and converts the Slave Laserlichtpuls into an electrical signal. The recurrence rate of the Slave Laserlichtpulses is regulated to a value (it is angedacht that this value close is because of 50 MHz), which is attained by adding a value according to the recurrence rate rule signal to 50 MHz (frequency of the electrical reference signal) (see Fig. 3 (C)). As a result the electrical signal possesses a component close of the frequency 50 MHz and a high frequency component (frequency clearly more highly than 50 MHz). The low-pass filter 217 is similar a component to the low-pass filter 117 and removes the high frequency component of an expenditure of the photodiode 216. The critical frequency of the low-pass filter 217 is e.g. 70 MHz. Therefore the high frequency component is removed, if the low-pass filter 217 receives the expenditure of the photodiode 216 and the frequency component passes close 50 MHz. The amplifier 218 is similar a component to the amplifier 118 and strengthens an expenditure of the low-pass filter 217. An expenditure of the amplifier 218 is called electrical measuring signal. Attaining the electrical measuring signal corresponds to a measurement of the light intensity of the Slave Laserlichtpulses. The electrical measuring signal is attained by strengthening the expenditure of the photodiode 216 by the amplifier 218 and possesses from there a tension based on the light intensity of the Slave Laserlichtpulses. The moreover one the electrical measuring signal passed and possesses the low-pass filter 217 from there a frequency close of the frequency of the before specified value of 50 MHz. The low-pass filter 217 and the amplifier 218 can be able to be interconnected in such a way to be interconnected like the low-pass filter 117 and the amplifier 118. In each case the electrical measuring signal the signal remains based on the expenditure of the low-pass filter 217. The reference comparator 222 is the same as the reference comparator 122 and therefore without a description of the same is done. The measuring comparator 215 is similar a component to the measuring comparator 115, which compares the tension of the electrical measuring signal (tension based on the light intensity of the Slave Laserlichtpulses) and a before specified value (like e.g. the electrical grounding potential) with one another and spends a result of the comparison. In other words, the measuring comparator 215 receives the expenditure of the amplifier 218 and the before specified tension, compares both with one another and spends a result of the comparison. The phase comparator (phase difference detector) 232 is similar a component to the phase comparator 132, detects the phase difference between the expenditure of the reference comparator 222 and the expenditure of the measuring comparator 215 and spends the phase difference. The loop filter 234 is similar a component to the loop filter 134 and removes a high frequency component of the expenditure of the phase comparator 232. The Piezo driver 236 is similar a component to the Piezo driver 136 and strengthens the expenditure of the adder 235. The expenditure of the Piezo driver 236 is supplied to the Piezo element 212p. As a result expanded/the Piezo element 212p in the X-direction contracts. It should be marked the fact that the Piezo element 212p is expanded in such a way/contracted that the phase difference, which by the phase comparator 232 is detected is a constant value (like e.g. 0°, 900 or -900). As a result the recurrence rate of the Slave Laserlichtpulses can be brought with the value in agreement (it is angedacht that this value close is because of 50 MHz), which is attained by adding the value according to the recurrence rate rule signal to 50 MHz (frequency of the electrical reference signal). The adder 235 adds the recurrence rate rule signal to an expenditure of the loop filter 234 and spends a result of the addition. The recurrence rate rule signal source 238 is e.g. a user defining waveform generator (arbitrary waveform generator) and spends the recurrence rate rule signal. The recurrence rate rule signal has a constant repetition cycle. The recurrence rate rule signal can e.g. as a sinusoidal wave (see Fig. ) to be represented or a linear rise and dropping can repeat 3 (A) (see Fig. 4 (A)), if the time is assigned to the horizontal axle. It is to be marked that the recurrence rate rule signal is a signal, which possesses a recurrence rate of approximately 250 cycles per second. In the following a description of the enterprise is given to the execution form of the available invention. (1) before the expenditure of the recurrence rate rule signal in this case are similar the function of the recurrence rate controller 1 to the enterprise of a usual PLL circle. In other words, the recurrence rates of the master laser light pulse and the Slave Laserlichtpulses reach MHz. Now a description of an enterprise is given, if the recurrence rate of the master laser light pulse reaches MHz. The same is valid for the recurrence rate of the Slave Laserlichtpulses. Regarding Fig. 2 (B) the electrical reference signal, which possesses a before specified frequency (e.g. 50 MHz), is spent by the electrical reference signal source 121. The moreover one the result of comparison between the tension of the electrical reference signal and the electrical grounding potential becomes (= 0 V) of the reference comparator 122 spent. As a result the pulse possesses the recurrence rate 50 MHz, which by the reference comparator 122 one spends. Therefore becomes regarding Fig. 2 (A) accepted that the recurrence rate of the master laser light pulse is shifted by MHz and the phase of the spent wave shape of the amplifier 118 is shifted of the wave shape of the electrical reference signal source 121 spent by the phase. In this case becomes regarding Fig. 1 the master laser light pulse, which from the master laser 112 it will spend partly the photodiode 116 of the optical coupler 114 supplied, experiences photoelectric conversion and passes the low-pass filter 117, from which the distance of the high frequency component results. The expenditure of the low-pass filter 117 is continued to strengthen by the amplifier 118 and compared by the measuring comparator 115 with the tension of the phase rule signal, which is identical to the electrical grounding potential (= 0 V). The phase comparator 132 compares the phase of the expenditure of the measuring comparator 115 and the phase of the expenditure of the reference comparator 122, detects the phase difference between the expenditures and spends this phase difference. The high frequency component is removed from the expenditure of the phase comparator 132 by the loop filter 134, the resulting expenditure is strengthened by the Piezo driver 136 and supplied to the Piezo element 112p. The Piezo element 112p contracted/expands in such a way the fact that the phase difference, which by the phase comparator 132 is detected possesses a constant value (e.g. 0°, 900 or -900). As a result it is possible to bring the recurrence rate of the master laser light pulse precisely in outvoting with the frequency to 50 MHz of the electrical reference signal. If a regulation is made available, so that the phase difference, which by the phase comparator 132 one detects, is o°, the spent wave shape of the measuring comparator 115 is shifted to the left and overlaps the spent wave shape of the reference comparator 122 in Fig. 2. Then the spent wave shape of the amplifier 118 coincides with the spent wave shape of the electrical reference signal source 121. Like that it is possible to bring the recurrence rate of the matte laser light pulse precisely with the frequency to 50 MHz of the electrical reference signal in agreement. After the recurrence rates of the matte laser light pulse and the Slave Laserlichtpulses agree with the before specified value fo (=50 MHz), if no interference is present and if the tensions, to which against that Piezo elements 112p and 212p rest, remain constant, the recurrence rates of the master laser light pulse and the Slave Laserlichtpulses can be held to the before specified value. Fig. the expenditure of the recurrence rate rule signal source 238 (Fig shows 3. 3 (A)), the expenditure of the adder 235 (Fig. 3 (B)), the recurrence rate of the Slave laser 212 (Fig. 3 (C)) and the recurrence rate of the master laser 112 (Fig. 3 (D)). Fig. 3 illustrates a case, in which the expenditure of the adder 235 to the value Vo is held and which are held for recurrence rate of the Slave Laserlichtpulses to the before specified value fo in one period of 0 ton (see Fig. 3 (B) and Fig. 3 (C)). The moreover one a case is shown, in which the recurrence rate of the master laser light pulse is held to the before specified value fo in the period of 0 ton (see Fig. 3 (D)). The expenditure of the recurrence rate rule signal is started in this case at the time ton. (2) after the expenditure of the recurrence rate rule signal it are accepted that the recurrence rate rule signal is represented e.g. by a sinusoidal wave, if the time is assigned to the horizontal axle (see Fig. 3 (A)). The expenditure of the adder 235 fluctuates then likewise upward and down with reference to Vo (see Fig. 3 (B)). If the expenditure of the adder 235 rises (drops), then rises the tension, which against the Piezo element 212p rests, likewise on (the tension, which against the Piezo element 212p rests, falls likewise off) and the PiezoElement 212p expanded (contracts). It is accepted that such is available a Design that the laser resonator length of the Slave laser 212 shortens (extended), if the Piezo element 212p expanded (contracts). Then the recurrence rate of the Slave laser 212 rises on (the recurrence rate of the Slave laser 212 drops). The recurrence rate of the Slave laser 212 fluctuates from there upward and down like the expenditure of the adder 235 (see Fig. 3 (C)). The value of the recurrence rate of the Slave laser 212, which fluctuates upward and down, is a value, which corresponds with the recurrence rate rule signal. On the other side the recurrence rate of the matte laser light pulse does not fluctuate in a special way (see Fig. 3 (D)). Fig. a modification shows and shows 4 in the expenditure of the recurrence rate rule signal the expenditure of the recurrence rate rule signal source 238 (Fig. 4 (A)), whereby the expenditure of the adder 235 (see Fig. 4 (B)), the recurrence rate of the Slave laser 212 (see Fig. 4 (C)) and the recurrence rate of the maser laser light pulse (see Fig. 4 (D)) in this case is likewise similar. While the recurrence rate of the Slave laser 212 fluctuates upward and down, the recurrence rate of the master laser 112 is constant in accordance with the execution form of the available invention and it is possible to bring the difference between the recurrence rates of the two lasers to fluctuating. It is to be marked the fact that the master laser light pulse and the Slave Laserlichtpuls for measuring instruments can be used which THz light uses. E.G. the master laser light pulse is supplied to a THz Lichtgenerator (like e.g. a light-conducting switch), whereby THz light is produced and the THz light on an inspection item irradiates. The THz light, which became to transfer by the inspection item through or by the inspection item was reflected, is supplied to a THz Lichtdetektor (like e.g. a light-conducting switch). So the THz light can be detected by supplying the Slave Laserlichtpulses to the THz light detector. There is a difference in the recurrence rate of the master laser light pulse and the Slave Laserlichtpulses and it can several points on a wave shape of the THz light be observed, which became to transfer by the inspection item through or by the inspection item was reflected.