JPH0135511B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a pulse forming circuit network for the excitation circuit of a horizontally pumped TE type high-energy laser device excited by a capacitor discharge generated between opposing electrodes extending parallel to the laser optical axis. It relates to a device for adapting.

The TE type high energy laser device and its characteristics are known from Patent Application Publication No. 29387 of 1981. A preionization device suitable for this device is described in German Patent Application Nos. 3035730 and 3035702. It is assumed that the high-energy laser device to which this invention is applied is equipped with this type of pre-ionization device. Therefore, consideration of the effective construction of the pulse forming circuit and the design of switching elements in its excitation circuit will not be discussed here. What is referred to herein as the excitation circuit also includes a laser head outside the pulse forming network with a high voltage switch.

High-energy TE lasers have become necessary for opto-mechanical applications, especially in industrial fields, due to their low cost and high optical power.

For the operation of this laser, it is advantageous for the characteristic impedance of the pulse-forming network to be as low as possible even when the rate of current rise is sufficiently high. This is achieved by a suitable combination of the inductance of the excitation circuit and the capacitance of the pulse forming network. In addition, in many applications of TE lasers, a laser pulse as long as possible is desired. This requirement can be met by making the excitation pulse a rectangular pulse with a steep rising line, a flat top line as wide as possible, and a steep falling line. The object of the invention is to design the device mentioned at the outset in such a way that, within its pulse-forming network, excitation pulses are produced which satisfy the above-mentioned requirements to the greatest extent possible. It has already been proposed to use strip conductor capacitors in devices of this type and to provide a cut in the capacitor metal layer connected to the first electrode on the high-voltage side of the laser chamber, increasing the length of the current path several times. ing. However, there is a limit to the pulse length that can be achieved with this structure, and a fundamental objective of the present invention is to extend the pulse length beyond this limit. Furthermore, in the case of a capacitor using a capacitor metal layer and a liquid dielectric, especially water, it is a principal object of the present invention to simplify and inexpensively manufacture the electrode plates thereof.

This object is achieved by the configuration listed as the feature in claim 1. Advantageous embodiments of the invention are revealed in the subclaims. The main advantage obtained by this invention is that the transit time series with different pulse extensions can be changed according to a single plan, and parameters such as capacitor partial layers, gap widths, and the size, number, and connection points of coupling coils can be changed. It can be easily made by simply changing it.

The present invention will be described in more detail with reference to the drawings showing embodiments of the invention.

First, as shown in FIG. 5, the metal layer B of the strip capacitor of the pulse-forming network is divided into rectangular or approximately rectangular partial layers _{B 1} , B ₂ and B ₃ by the junction sections g ₁ , g 2 . and adjacent partial layers are connected through a connecting inductance L ₁ or L ₂ .
The height of each partial layer (on the diagram) is h _i (i=1, 2,
3,...), and its length is l _i (i=1, 2, 3,
). Depending on the length of the metal layer B or the length of the transit time sequence, there are n sublayers, n-1 coupling inductances and n-1 junction sections. Here, n≦2.

The coupling inductance L _i is made as a small coil as shown in the figure, the size of which is related to the desired pulse delay time. The coupling inductance may be a short piece of wire. In FIG. 5, a coupling inductance L _i is connected to the upper and lower ends and the center of the edge of the partial layer B _i so as to bridge the joint section.
You can change the connection points for each joint section and alternately connect the top and bottom ends to create a strong meander-shaped current path, or leave the center coil as is and create a weak meander-shaped current path by leaving every other coil above and below. It may also be used as a current path. The coupling inductance is connected to the respective partial layer by an intermediate metal bond such as soft soldering or hard soldering, or by welding. In principle, it is also possible to use mechanical coupling methods such as tightening, insertion, screwing, or wire wrapping. As can be seen from Fig. 5, the partial layer B _i and the joint section g _i
are of equal size. However, depending on the area of the partial layer B _i , the width of the junction section, the coupling impedance
It is also possible to make the LR values of L _i at least partially different. A is a bonding plate for connecting the metal layer B to the laser electrode or the electrode of the high voltage switch FK. The division method shown in FIG. This applies to metal layers 2 and 3 of one second strip conductor capacitor C _F , C _K .

When the pulse forming network PEN is the charge transfer circuit shown in Figures 3 and 4, the capacitor metal layer structure shown in Figure 5 is at least a strip conductor capacitor.
Applied to metal layers 2' and 3' of C _F ' and C _K '. These metal layers are commonly connected to the laser electrode E _L2 . In another embodiment, this structure is also adopted in the metal layer 4' of the first conductor capacitor C _F ' in addition to these metal layers 2' and 3'.

Figures 1 and 2 show the West German patent application publication numbers.
2932781 is shown, which consists in particular of the high voltage switch FK, the laser head LK, the connecting conductor and the inherent inductance of the strip conductor capacitors C _F and C _K. equivalent inductance L _F and L _K
is marked with a broken line.

Correspondingly, a known laser excitation circuit is shown in FIGS. 3 and 4, which includes a pulse-forming network PFN as a charge transfer circuit. Here, too, the equivalent inductances L _F ′ and L _K ′ are drawn in broken lines. In Figs. 1 to 4, LK is a laser head or a laser chamber, inside which at least two laser electrodes E _L1 and E _L2 are opposed with a distance maintained between them, and a uniform gap is formed between these electrodes. An arc capacitor discharge is excited by high voltage pulses produced by a pulse forming network. FK is the high speed high voltage switch mentioned earlier, for example with electrode E _F1.
Configured as a spark discharge chamber with E _F2 . It may also be configured as a thyratron or plasma switchgear. R _K is an impedance connected in parallel to the laser discharge interval, and has a high resistance value compared to the laser internal resistance. HV represents a high voltage or high voltage terminal, and the horizontal line s represents the capacitance unit C _F ,
It represents the plane of symmetry of a capacitor stack consisting of K or C _F ', K'. Instead of the mirror-image arrangement of the capacitor units shown in the figure, an asymmetrical arrangement can also be used. d is the capacitor dielectric, solid, liquid or gas, particularly highlighted with crosshatching, and o is the optical axis of the laser chamber LK.

In FIGS. 3 and 4, the strip conductor capacitor, the capacitor metal layer, and the equivalent inductance are each given a prime sign ('), but the other parts are the same as in FIGS. 1 and 2. Figures 1 to 4
The figure shows two embodiments of the pulse forming network PFN, but other configurations such as an expanded type or one using chemically purified water as a derivative may also be used. When determining the size of the coupling inductance, it is necessary to consider the equivalent inductance L _F , L _K or L _F ′, L _K ′. C _K ′ or LK
−L _K ′ The impedance of the high resistance compared to the laser discharge gap connected in parallel to the series connection is shown in Fig. 3.
It is shown as R _F in Figure 4.

[Brief explanation of drawings]

Figures 1 and 2 are wiring diagrams and configuration layout diagrams, respectively, of a laser excitation circuit as a Briumline circuit, and Figures 3 and 4 are wiring diagrams and configuration layout diagrams, respectively, of a laser excitation circuit as a charge transfer circuit. , FIG. 5 shows a configuration diagram of an example of a divided structure of a capacitor metal layer. FK...High voltage switch, LK...Laser head, EL ₁ , EL ₂ ...Laser electrode, PFN...Pulse forming network, C _K and C _F ...Strip conductor capacitor,
L _F , L _K ...Equivalent inductance.

Claims (1)

[Scope of Claims] 1. A laser head LK with electrodes extending parallel to the optical axis within the laser chamber; a high-speed high-voltage switch FK for applying high-voltage pulses to the laser electrodes EL1, EL2 through a pulse-forming network; A device for adapting the pulse-forming network to the excitation circuit of a high-energy laser device, consisting of a high-voltage switch and a pulse-forming network PFN that includes two strip conductor capacitors C _F and C _K assigned to the laser head. In, the pulse forming network
When the PFN is a Bryum line circuit, the metal layers 1, 2, 3 of the two strip conductor capacitors C _F , C _K ,
The metal layer 4 connected to the laser electrode of at least the second strip conductor capacitor C _K in 4 is (n-1)
It is divided into n partial metal layers B _{1 ,} B ₂ , ...B _o with joint sections g 1 , g ₂ ... _go-1 , and the adjacent partial metal layers B have connection inductances L ₁ , L, respectively. ₂ ...
conductively coupled to each other through L _o-1 , and common to at least one laser electrode in the metal layer of the two strip conductor capacitors C′ _F , C′ _K when the pulse forming network is a charge transfer circuit. One partial surface of metal layers ₂ ', _{3 '} connected to 2. The interference generated between at least two opposing laser electrodes in the gas space of the laser chamber, characterized in that the partial metal layers B are electrically conductively coupled to each other through coupling inductances L ₁ , L ₂ . . . L _o-1 , respectively. A device for adapting a pulse forming network to the excitation circuit of a TE type high energy laser device excited by an arc capacitor discharge. 2. Device according to claim 1, characterized in that in the case of rectangular parallelepiped capacitor deposits, each partial metal layer B has a rectangular base of height h _i and length l _i . 3. Device according to claim 1 or 2, characterized in that the coupling inductance L _i is made as a small coil. 4. The device according to claim 1 or 2, characterized in that the coupling inductance L _i is a small piece of wire. 5. A patent claim characterized in that the connection points of the coupling inductance L _i are placed at discrete points on the boundary edge of the partial metal layer B _i or are continuously distributed on the height side of the partial metal layer B _i Apparatus according to one of the ranges 1 to 4. 6. The coupling inductance L _i is connected to the partial metal layer B _i by an intermediate metal bond such as soft brazing or hard brazing, or by a mechanical method such as welding, insertion, tightening, screwing, or wire wrapping. Device according to one of the claims 1 to 5, characterized in that: 7. Device according to one of claims 1 to 6, characterized in that the area of the partial metal layer B _i and the length of the connection section g _i are each approximately equal. 8. Claims 1 to 8, characterized in that the area of the partial metal layer B _i , the width of the coupling section g _i , and the L and R values of the coupling inductance L _i are at least partially different from each other. Device according to one of paragraphs 6.