DE2056543C - Optical transmitter for giant impulses from a gaseous stimulable medium - Google Patents

Description

The present invention relates to an optical transmitter for giant pulses from a gaseous stinnable medium, the excitation of which is transverse to the optical (longitudinal) axis by means of a high current charge takes place in such a way that the grounded U-rail-shaped base electrode the discharge channel, which also represents the optical resonator, over its entire length enclosing three sides, their side walls being covered with insulation, on which as a conclusion of the discharge channel rests on top of the anode, which in turn consists of a symmetrical over its length Discharge circuit connected to a high voltage source via a storage capacitor is fed, as well as a circuit for such an optical transmitter.

ίο With known electrical nitrogen and neon pulse lasers the laser beam is triggered by a pulsed electric field. In the discharge circuit used inductances limit the discharge current, with failures at the High-voltage lines belonging to the discharge circuit are common phenomena. The discharge current has been limited to a value which is considerably below the value at the time of limitation only by the discharge resistance> "of the discharge space iag.

In a known cross-field laser, the electrical energy flows from a conventional high-voltage source charged capacitor through several low inductance transmission cables an upper electrode that runs along the active Zone or the discharge space occupying the optical resonator extends. A U-shaped one Channel serves both as a structural support for the device and as a counter electrode. The discharge takes place between the dielectric side walls. Given the short time scale required, the Power distribution initially controlled essentially by the existing inductances. In normal Operation when there are no arcs and failures due to local overload, especially when one or more of the high-voltage cable traps connected in parallel cannot be reached via extremely uniform discharges along the entire length of the channel.

Due to the inductance dependence of the current distribution, however, there is an extremely low inductance to strive for Hochspan.vjngskabei. This contributes to the failure of the cables, especially at high Impulse follower a '. \ Conversely, a reduced pulse train rate increases the likelihood of cable failures at least proportionally back. In addition, the Hochsrunnungskabel must take into account the high voltage used (usually 20 kV) can be exposed undesirably, a not inconsiderable one High voltage stray radiation occurs because each cable acts as an antenna.

Accordingly, the aim of the present invention is to to create an optical transmitter of the type mentioned, which these disadvantages of known gas lasers avoids and which works reliably with high efficiency with a simple design.

According to the invention this is achieved in that the one piece covering the discharge space The anode carries the storage capacitor that further 60 a series of charging capacitors connected electrically in parallel to the discharge path along the Anode are arranged evenly distributed within a flat, electrically conductive box, the rests on the U-rail and is directly connected to it 65 also electrically to ground.

The inventive optical transmitter results in a Light generation at a high output level, whereby to generate the pulse-like electrical

Field in the Gasentladungsnicdium a discharge circuit is provided. Advantageous embodiments of such a discharge dial are based on claims 2 to 4.

In the following the invention is intended to hand an exemplary embodiment is described. reference being made to the drawing. It shows F i iZ. 1 is a perspective view of an embodiment of the invention to show partially cut details. S. 2 a circuit diagram of the export .ui ^ sform F i g. 1 and

. . £. 3 shows a circuit diagram for FIG. 2 kür / after you Zi: 'Young of the Thyratron.

ii α. 1 shows a laser 10, the centers of B; ims Π "Λ a housing (not shown) attached w -Jen can.

he base 11 is a U-shaped part, from geii tem. Good conductive material, such as Alun um, made with two sides, IK / and lift ν ■ an intermediate i'.inbuchti'n 'or ν. πι Boden Mr. In the base 11. uic auDen.le; r, which serves as ι Λ death, there are two '"■ itenwinde 12 <j and

Line cover 22 and right-angled sockets - extend the entire length of the base . A cylindrical part 24 is eetra-en from the cover 22 and is connected to this via a flange -

connected. The parts 22, 23 and 24 wearι unu -chut / en the uw-eordnine components and miucn therein the reverse for the charge current. The Miiizteil 23 is inter alia with the base II by means of screws Irish and mechanical connected and can

The maintenance tasks can be easily removed.

The electrode 13 is connected to an energy storage device

capacitor 26. a plurality of secondary capacitors 27 and a resistor 28 in connection. The secondary capacitors 27 are located within the cover 22 and the support -J. ^ Secondary capacitors in anmcr se ^ way up a screw 29 for Aulnahm ". a screw 31 and two threaded pins 32 on -iscn. nsosoo one (preferably the innert, the »other connection hildel» / bor the C.cwind ^ U J- are the capacitors, on part 23 it. urn electrically conductive! mat 33 deck d, .U 13 from and .st with the upper, lAnschhß29 dr capacitors 27 via screws 31 t \ Λ nscη anu

, 5

Bas.s des

rode serves,
h are present that consist of specific isolation, e.g.

stand. The outermost section] of Seiten.ande la and 12ft have a relatively thin, directed flange, tine electrode 13. be, -

ielswcisc made of aluminum, but the sides • Worn and located between the

.ch upward flanges of the rope, α ande

2, and I2ft. In addition, the electrode 13 is used. To keep the partition walls separate, one that avoids arcing on the parts Ua and Ub , the electrode 13 and the base 11. To maintain the distance between the lower files of the partition walls, several punching pieces 14 or a gradation can be provided in the base. The space thus formed between the side walls represents a relay, 0 narrow, elongated discharge canal. They secure one to the other end of the laser

'Enticing 16 uad 17, m floor, 1, the Bases 11 serve as inlet and outlet for the (, as through the floor lic. So that this through the ent- ■ loading space 15 can flow.

Two transparent windows 18. 19 close the
Discharge space on both of its ends. This
Windows and 19 are for light from the wave 5,
length of the radiation generated in the discharge space
permeable _E. They can be made from quartz or one
other known material mn the required ^ j ^ ^ ^

Properties exist. ί,, in ι, ηπ a common C'.limmer

During the operation of the laser 1 "is in the Ent- 55 condensa or 26" nn c η L JJjmc ^ ^

Charge space 15 a pressure of 15 to 25 Torr on-condenser ^ J ^ Jj J ™ _{tf) rcn 27 crford} cr-

keep right. The discharge space 15 must therefore 4c Stku, darkonjtn «"".

be sealed pressure-tight. The various hdu ^ " ^l ^ f ^ ⁿ ^ ^s ^, ^" _{er Ladcsc} haliung with

Contact surfaces between the side walls of the condenser or 26 w.rd ν η c .κr _{ül 38 gc} .

Base 11, electrode 13 and windows 18 and 60 a ^ «. Rshind 37 _mi; Ts to a high

19 are therefore loaded with a suitable putty or. ^Dlt _λ ^ ,, ^ 39 for kV

a sealing material sealed so that the En, - SpannunpanschIuB 3Mur

Cargo space 15 at least relatively gas-tight *, approx. ges Mo c, D ^ L de.c fc

According to Fi ^. 1 is on the translucent shoot of the laser "».

Window »an adjustable mirror 21 arranged 6 ₅ e, ne r follower o 1.

preferably coated with aluminum and on more. ? " ^Λι - ^{Γΐ iIl} ". "

known lines perpendicular to the longitudinal axis of the duck, a 38,. «i m«

cargo space 15 adjustable. "" ^

mechanically connected. Liulang the stretches see emc spring ^^ Sc ^ binds de plate 33 electrically m, t the LI Hin in the trade .eher ^l ^ ^r sator 26 with Cil.mmerd, Jek.nkum ^

Screw connection on one land η.cht over the latter with the plat u 33 fts tb ndc the storage capacitor 26

medium 3 *. _ f ^ ;;; gp \ Vasserstoitth> ra mn S. (lg "« ^ _Un . capacitor and Γ>;<»« J den sk ^ ^ ^

dnsehen U - ⁴ D ' ¹ , ¹ , ¹ ' _e running fin connection of the and the Abd.cku "<- ^ ^r ^, screwed on switch 1 tm UeIs 3s is π η tm _wüh .

closing of the memory o ^ Uη ^ν ^ ^r \ ^ _{allmittds mll dcr} rend der am ^ ^ l ^ ^d ^ *; ^h ^ _{ndling stchl} .

^ - each other Lgs of whoever em ^ irn spaced ^. and h, the ^ P _den .

-rstand ¹ S The secondary capacitors e stood'- «^ * _Cnügcnd energy for

de Inversion im J "" ¹ ^ the switch compartment 1 ^ ^^^ ° ^ ^α ^ _{Γ cine} , rigger- nun, b / »das Ih ^ ratain 35 ^ ^

cherishes

_{38 gc}

a Hochise 20 kV to- _{| I |} ^ _{n Bc} .

_n , second or 37 and the In _{on dic} highest

and inductance 38 also act as an Isn- a minimum. F i g. 3 shows the equivalent circuit between the high voltage source 39 and during the commutation of the thyratron 42 of the rest of the circuit. Heim Alis guide example (Fig. 2). In Fig. 3 represents a direct current source V had the resistor 37 250 k. '.' and inductance is the charge on the Spcichcr-38 KM) M designated _{as C 1.} ^s condenser 26. The time-dependent voltage V Hei known Ouerfddlasern are in a waste represents the anode voltage drop of the thyratron 42 deckiing mounted loehspannungsbuchscn 1 represents a. The inductance L ₁ represents the equivalent series of coaxial high voltage cable. The series inductance of the thyratron 42 and the linden tree are these parallel-connected cables storage capacitor C ₁ . The inductance L., rcover the mentioned sockets at equal intervals io presents the equivalent series inductance of that connected to the upper electrode, while its secondary capacitors C ₄ . An equivalent series of other linde via a triggered spark gap inductance of the laser arrangement is through L ₃ darodcr a thyratron with a storage capacitor. placed. A variable resistor r represents the resistance, generally of a bank of capacitors, in relation to the gaseous medium in the charge space. The energy supply to the capacitors 15 15 represents.

bank takes place via a high-voltage direct current- Immediately after commutation of the Thyra-

source that applies with a current limiting resistor irons /, = -. I ₂ 0, the voltage across the

is in series. The high-voltage cables are connected to the capacitorcn is 0, and the resistance is r des

Cover part to ground and close the gas circuit is practically infinite. Then it rises

Via the cover part and the bast part to the gas 20 charge on the secondary capacitors C ₂ , while

shaped medium in the discharge space. the current / ₂ remains approximately at the value 0, since the

From Fig. 2 in connection with F i g. 1 detects the resistance of the gaseous medium in the

one that several secondary capacitors 27 approximately charge space 15 is very large until the

at the same distance across the discharge space 15 parallel voltage across the secondary capacitor C _{t has} a value

are switched. They lie, as shown in FIG. 2 shows, also reached 95, which is sufficient for breakthrough in the gas,

like the resistor 28 parallel to the electrode 13.

and to base 11. The secondary charge space 15, which is held in parallel, discharges from the secondary condenser

Capacitors 27 are connected to the storage capacitor C ₂ via the equivalent inductances L ₁

sator26 with the anode 41 of a thyratron 42 in and L., "in the gaseous medium. By correct

Connection. The control grid 43 of the thyratron 42 30 choice of the secondary condenser ₈ and by the

The construction of the laser channel shown on a normal trigger circuit 36 can be used

closed, while the cathode 44 of the thyratron significantly increased the equivalent inductances L _t and L ₃

is grounded via the base 11. Make the anode 41 of the smaller than the equivalent inductance L ₁

Thyratron is connected to the series connection of the thyratron and storage capacitor. At the other

Resistance 37 and the inductance 38 at the given implementation of the circuit inductance

High-voltage supply 39. The high-voltage one reaches a laser peak current, which is

supply39 and the trigger circuit 36 are borrowed above the peak current of the thyratron,

one terminal connected to ground. In addition, the laser peak current has a bc-

The considerably steeper current rise connected via the discharge space 15 than that

Resistor 28 has a larger resistance 40 thyratron and the equivalent inductance L ₁

allow yourself worth than the resistance of the gas discharge path.

and is small compared to resistor 37. If only resistor 37 is present, the energy storage capacitor 26 should about an in-works the circuit when operating with a single inductance of about 5 nH or less and a pulse or lower pulse repetition rate of about 12 have nF at 20 kV. Placing at 45. If, on the other hand, only the inductance 38 of these values is seen, the stored charge is sufficient. before. so the circuit can only work with one pulse around the suitably dimensioned, discharge sequence rate, and the required high space 15 secondary capacitors 27 voltage is reduced to about half the load and thus a uniform discharge in the correct combination of Create resistance and entrapped gas. If at 50 ductivity results in a charging circuit that has a circuit according to FIG. 2, the capacity of the condenser drive with individual pulses or high follow-up rates27 at the discharge space 15 is equal to zero, (100 pulses per second) and with solid cutting, the laser device does not work satisfactorily or over- r · mgsquelle does not allow the combination of the contradictions. Are umg- ^v; hrt these capacitors ru residues and inductances of the charging circuit becomes large, so it does not reach a breakthrough in the gas 55 in combination with the energy storage capacitor of the discharge space 15, as preferably selected during each pulse so that a critically damped not sufficiently high voltage is being built. The circuit is created. "Critically damped" means the optimal size ratio between the secondary capacitors 27 and the storage capacitor 26 are selected so that the circuit parameters are that the storage capacitor is around 0.8. 60 interpulse interval at least approximately to the The circuit according to FIG. 2 reduces the current that charges when the supply voltage is full, practically without known lasers, current limitation to overshoots and without attenuation.

1 sheet of drawings

Claims (4)

Patent claims: 1. Optical transmitter for giant pulses from a gaseous stimulable medium, the excitation of which takes place transversely to the optical (longitudinal) axis by means of high-current discharge in such a way that the grounded U-rail-shaped base electrode forms the discharge channel, which also represents the optical resonator, via ι encloses its entire length on three sides, its side walls being covered with an insulation on which the anode rests at the top as the end of the discharge channel, ü ^; e in turn is fed symmetrically over its length from a discharge current circuit connected to a high voltage source via a storage capacitor, characterized in that the anode (13) covering the discharge space in one piece carries the storage capacitor (26), and furthermore a series of electrically parallel the anode is distributed evenly arranged within a flat, electrically conductive box (22, 23} ntladungsstrecke geschaltften charging capacitors (27) along which rests on the U-Sehiene (11a Il b) and directly with it electrically ^with: for I.. Ground is connected 2. Circuitry for an optical transmitter Claim 1, characterized in that a bleeder resistor is parallel to the LaJekoncensatoren (27) (28) is connected to ground and the charging capacitors are connected to the inner pole of a storage capacitor (26) are connected directly to the anode (13), which in turn is connected to his other pole with a high voltage source (39) is connected via an inductance (38) and a larger ohmic charging resistor (37), being parallel to the storage capacitor (2o) together with its bleeder resistor (28) Thviatron (42) connected in parallel to ground is. whose grid (43) is controlled by a pulse generator (36) and whose anode (41) mi ', the capacitor (26) is connected. 3. A circuit according to claim 2, characterized in that the ratio of the capacitances of the totality of the charging capacitors (27) to that of the storage capacitor (26) approximately Is 0.8. 4. A circuit according to claim 2, characterized in that the value of the to the Ladekoncjensatoren (27) lying side by side and a bleeder resistor connected to its two electrodes (28) is large compared to the resistance of the gas (15) after ignition and is small compared to the charging resistance (37).