DE1300180B - Optical transmitter or amplifier - Google Patents

Description

1 2

The invention relates to an optical transmitter or cross section of a resonance light amplifier, which by Amplifier whose monochromatic radiation is excited by a discharge in the resonance cavity emanates from a gaseous, stimulable medium,

its atoms, ions or molecules by collisions F i g. 6 is a diagram of the energy levels of the

with other particles to the higher level of two 5 iodine molecule, which is used to explain an embodiment pair associated stimulable energy example of the invention is used at the coincidence of states are excited, which with regard to their energy spectral lines when exciting a working medium in a light amplifier is used by an amount corresponding to the light frequency, differ so that the atoms, ions or F i g. 7 is a diagram of some energy levels of

Molecules of light photons as a result of stimulated emission io zinc, which is used to describe an execution during the transition from the higher to the game of the invention serves and in which an inner one send out lower level of the two energy states. When discharging to excite the working medium takes place, the well-known optical transmitters or amplifiers ". ,. ,,. ,

the output power was limited by the fact that a non-resonating light amplifier

Finally, collisions between atoms, ions, or molecular i ₅ ^with discharge ^mnerer

cooling a gaseous stimulable medium and FIG. Figure 2 shows a non-resonating light modifier Particles to excite atoms, ions stronger, in the gaseous medium in the cavity or molecules to the higher level of two pairs directly by supplying high-frequency energy and related stimulable energy states is not stimulated by a light source (lower same were used. Simultaneously with the ao frequency energy or a direct current discharge like bumps found a certain emptying which could be used instead if desired), lower energy level of these atoms, ions or beMolecules as a result of spontaneous emission. This agreed advantages over the relatively simple spontaneous Emission, however, caused the emptying to be excited by resonance radiation, which was mentioned above lower energy level of these atoms, ions or 25 was written. In this way of working, a Molecules too slow for a considerable over-improvement of the intensity by collisions Shot of atoms, ions, or molecules on the second type used to "determine the intensity of a." higher energy level compared to the number of the special spectral line of a lamp, The same is done at the lower energy level. Extensive studies have been carried out to determine

would come. 30 to explore the phenomenon of secondary fluorescence.

The object of the present invention is that the atoms of a kind, which at a certain Elek-speed the emptying of the lower energetic trons are stimulated, can at level together of these atoms, ions or molecules is increased. collide with atoms of a second kind

According to the invention, this is achieved in that means transmit energy. It was designed experimentally and theoretically are, the other shocks (of a second type) 35 retically proven that the transfer process generate to the named atoms, ions or moles- is most likely when two conditions küle on the lower level of the two energies are fulfilled:

states to empty more quickly, and that the combination ( _a ) j _{e of} your is the energy difference between the ionization of the first collisions and the other collisions of such a state of the two types of atoms that of

are that a relatively higher population of the 40 mentioned are of interest, the greater the cross-acting atoms, ions or molecules of the gaseous stimulus _{for an exchange when}

Able medium m the higher level of the two encounter

States is generated (b) The total electronic torque of the two

In this way a considerable improvement is _{atoms Weibt dassdbe before and after to} _

the excess atoms ions or molecules 45 _sa mmenstoß (part selection rule of W ig η s). m the higher state compared to those in

reached the low energy state, so that also in connection with rule (a) the energy

the output power of the optical transmitter or the difference in or from the kinetic energy of the atoms is increased considerably. be converted when the energy difference

With reference to the drawing, the invention and 50 less than the thermal energy (<K ^ s 0.03 eV) should elucidate its features and special advantages and if rule (b) is met, the cross section can be refined. It shows more than a hundred times the cross section according to

F i g. 1 is a Grotrian diagram of the energy levels of kinetic theory. ^{In particular, 55 stable Hg (6 3} P ₀ ) atoms and sodium atoms in were of sodium, which serves to explain the light-intensifying collisions of the second type between metakende devices according to the invention

F i g. Figure 2 shows a cross section in partially schematic view of a mixed gas. From the diagram represented by a non-resonating light in Fig. 1 it can be seen that the Hg (6 ³ P ₀ ) level is amplified by an electrical discharge in between the Na (7S) and the Na (6P) level located in the amplifier cavity, and differs from both by <0.045 eV.

F i g. 3 is a partially schematic representation of a 60. It was observed that the visible Na (7S -> 3P) resonance light amplifier, which is so intense under certain conditions due to incoherent light 4751 λ line radiation is excited and a triangular prism like the Na (3P -> 3S) -5983-Ä-Line became, which shows, with reflective surfaces, that the main amount of the energy is due to the Na (7S) -

F i g. 4 a partially schematic representation of a level has been transferred. The intensity improvement cross-section by an optional optical system 65 tion is about twenty times. It can be requested the facility in FIG. 3, in the z. B. only in the assumption that transitions from the 6 Ρΐ /., Level Paper plane polarized light is generated, are favored in the same way.

F i g. Figure 5 is a partially schematic representation of the exact mixture of Hg in Na amalgam in order to

Obtaining the necessary pressures of Na (~ 10 " ⁴ Torr) and Hg (~ 1.0 Torr) at working temperature can be taken from publications or approximately calculated from the law of R a ο u 11.

From the preceding explanation it can be seen that when using collisions the second kind with a different kind of atom the efficiency of the process by which a stronger occupation

and 3000 times as intense as the weak background created by spontaneous emission that it is is superimposed.

In addition, the non-resonating light amplifier exhibits short-term frequency fluctuations has a long-term average frequency that is very constant. Therefore, by means of the Frequency a light for a limited period of time

absorbed and converted to a large extent into usable work output. When an internal discharge is used to excite the atoms, a large amount of "pumping" power can enter the cavity 5 are coupled.

The usefulness of non-resonant light amplifiers is somewhat limited by the high noise level, which results from the output signal. There will be random fluctuations in the frequency or phase of the signal

a higher energy level generated by optical pumping io through spontaneous transitions. In particular is generated can be considerably increased and the usefulness of the non-resonant device an increase in the efficiency of the working as an amplifier (as opposed to an oscillator) wise the light-amplifying device leads. this background of random spontaneous emissions

According to FIG. 2 is a cavity 31 with a restricted, which gives the reason for a sound band opening 32 for the passage of the exiting light 15 width of approximately 1000 megahertz (the Doppler provided in the outer space of the cavity. A width of the spectral line). The approximately equi-rod 34 made of transparent material can be used to pass the light from the device on to the valente noise temperature of the non-resonant device. The light amplifier is in the center of the visible. Spectrum 30,000 ⁰ K. On the other hand, the interior 36 of the cavity is preferably * ° resonating light amplifier when it is filled as an oscillator with a gaseous medium, e.g. B. works with, an optical line that is up to 50 times narrower to a mixture of mercury and sodium vapor,
as mentioned above. The wall 37 of the
Vessel 31 is provided with a reflective surface 40
provided, the z. B. consists of magnesium oxide. A 35
Reservoir 38 is via a line 39 with the
Cavity 36 of the vessel 31 connected to give a gaseous atmosphere of the desired composition and the desired pressure in the cavity 36. For the reservoir 38, a heater 41 is provided to a degree of accuracy in a frequency normal manner which is obtained from one controlled similarly to the any temperature controller 42, which is one of a known frequency normal. Such a control of the vapor pressure in the cavity enables normal is not only advantageous for time measurements, light is. Excessive pressure fluctuations in the but also for distance measurements through the internal cavity 31 and a condensation in the cavity 35 ferometric method, which is later prevented in the cavity 36 by keeping the cavity 36 connected to a temperature controlled by the furnace 43 for this purpose .

In order to excite the atoms in the cavity 36, energy is supplied via a coil 44, which the 40 Surrounds cavity and is fed with high-frequency excitation energy, e.g. B. with a frequency of about 100 megahertz.

In the facility according to FIG. 2 follows a
Excitation of the atoms in cavity 36 is dependent on 45 measurements of the cavity in which the discharge and oscillation caused by high-frequency energy are generated.

not by light excitation. An optional embodiment of the lighting

Of course, the discharge in cavity 36 can be further described below, wherein can also be done in other ways, e.g. B. by a the resonance frequency of the device strongly from the DC or low frequency discharge depends between 50 dimensions of the cavity. The reso electrodes in the cavity or by capacitive nanzlichteamplifier differs also in others Coupling of high-frequency electrical energy in important features, but becomes the resonance indicator Cavity, instead of the one shown in FIG. 2 illustrated shaft of the device as a convenient way for inductive coupling. its differentiation from the one previously described

The advantage of generating a discharge within- 55 non-resonating light amplifier used
half of the cavity instead of the dependence on F i g. 3 shows an elongated cavity 51 which indicates

the absorption of energy from a light source is terminated by end pieces 52 and 53. readily understandable when one takes into account, as with the non-resonant device is a that only about 20% or less of the light energy, the reservoir 54 provided to the interior is passed into the cavity, for generating useful 60 zuzulicher the cavity a gaseous atmosphere Pump action is absorbed. In addition, lead. A heater 55, which acts as a heating coil

suitable facilities should be explained in more detail.

Resonance light amplifier

The above-described light amplifier according to FIG. 2 was used as a non-resonating light amplifier because the frequency of the light at the exit, although it is relatively constant, is not in to any substantial extent from the Ab

only a limited amount of "pumping" light can be introduced through a small opening. As the opening is made larger, the loss of light from the cavity becomes considerable. If the discharge takes place inside the cavity to excite the atoms, practically all of them will be in the Energy introduced into the cavity in the working medium

is controlled by a temperature controller 56 to regulate the pressure in the cavity 51 to ensure.

65 As in the case of the light amplifier according to FIG. 2, a furnace 57 can be provided, which is a part the device and keeps it at a temperature higher than that of the stock

5 6

holder 54 is, whereby a condensation in the requirements that must be avoided on its good flat and parallel cavity 58 and a better regulation training are preferred,
the pressure of a gas atmosphere is made possible. That is why the use of prisms is great

From the previous explanation it can be seen of practical importance. The cross sections of the prisms that the interior 58 of the cavity vessel 51 according to 5, 69 and 71 are right-angled threes according to the figure Embodiment of the invention with a corner. The surfaces 73 of the prism 71 run like that gaseous medium is filled, the pressure of which with surfaces 72 of the prism 69 (one of the surfaces 72 is Using the temperature controller 56 can be regulated. not visible because of the position of the prism 69) right-that gaseous medium in the cavity 58 at an angle to each other. Such 90 ° prisms can F i g. 3 is sodium in this example, although io can also be ground with great precision. if other media can be used, as the prisms are already ground in this way, light has been explained. radiate into the surfaces 75 or 74 of the prism 71 The excitation of the medium occurs in the cavity 58 or 69, as is well known, almost exactly in the takes place with the help of a hollow cylindrical gas thrown back direction from which they came. the Charge lamp 59 which surrounds the cavity vessel 51. 15 Reflection takes place within a considerable scope Gas discharge lamp 59 is preferably one of the angles of incidence of the diagonal surface (e.g. 75 Sodium vapor lamp using a suitable gas of the prism 71). In addition, the effective way is or a combination of gases, such as sodium, or the length of the rays passing through the diagonal surface 75 Argon, is filled. pass through, practically the same along the upper The outer wall 61 of the lamp 59 can with an ao surface of the diagonal surface, although the angle, below reflective surface, e.g. B. from magnesium oxide the blasting impinge on the diagonal surface 75, be provided to hold back light while it is not exactly 90 °. The prisms 69 and 71 are Inner wall 62 of the lamp 59 preferably for the preferably arranged so that their parallel desired spectral components of the edges of the lamp form an angle of 90 ° to each other, generated light is well transmissive. 25 This means that in FIG. 3 the edges of the prism 69 The wall of the cavity 58 is preferably flat-vertical, while the edges of the prism 71 if well permeable to this light. Of course, it can run horizontally.

if desired, a single wall between the

Interior 60 of lamp 59 and interior 58 right to the direction of the incident light rays of the vessel 51 by running these two 30, the prism 71 can be several degrees around Parts of the device as a coherent vessel are rotated along a horizontal axis, which is be formed. The wall 62 can extend from a perpendicular to the plane of the drawing without a Material consist, if desired, as an optically noticeable change in the direction of the reflection Filter is used, whereby certain undesirable compo takes place. Correspondingly, the prism 69 can increase by several nenten of the light of the lamp 59 excreted can be rotated 35 degrees around a vertical axis without can. The lamp 59 can also with a benefit that a noticeable change in the direction of the storage tank 63, a heater 64 and a reflected radiation takes place. Hence the situation is the Temperature controller 65 in a manner similar to that of the two prisms 69 and 71 is not critical in terms of respect Void vessel 51 may be provided so that the pressure in on a rotation about each of the mutually orthogoder Discharge lamp independently with the help of the temperature- 40 nal axes which are parallel to the refracting edges raturreglers 65 can be regulated. The prisms can be seen. Therefore the prisms 69 nen that the furnace 57 also the interior of the discharge and 71, if they are within the required tolerance charge lamp 59 holds at a higher temperature, limits for the level training and the angular position than corresponds to the temperature of the storage container 63. the different surfaces are sanded, in which The lamp 59 is provided with electrodes 66, the 45 cavity 58 without particularly critical requirements fed by an energy source 67 via lines 68 with regard to the parallelism of the end faces 74 and 75 will. The type of electrical excitation the lamp will be used for.

59 Can Be Chosen To Get The Best Results There are several alternative ways to get around

can be achieved in a specific use. For the critical character of the angular position of the Reflek example can reduce excitation by direct current, 50 gates. For example, the prism 71

Alternating current or high frequency. through a corner reflector with three mutually perpendicular

It has already been pointed out that there are right flat surfaces (which also have a prism It is worth seeing to provide a device around which can be) and the prism 69 through a plane mirror Limit light energy in the cavity and be replaced. The mirror can be multilayered

withhold so as to be a number of emissions of 55 reflector with little loss, the only light of the Light energy is excited and the intensity of the desired wavelength is selectively reflected.

Light is increased, whereby an amplification It is probable that a limit of the effect

in a roughly analogous way as with an electron multiplication of the system the tolerances are with which

subject tube due to the avalanche effect. flat optical surfaces can be produced.

The device according to FIG. 3 differs from 60 Practically speaking, it may not be possible to find a

from the above-described non-resonating light surface with narrower tolerance limits with regard to amplifier in FIG. 2 in that the reflectors of the flat training as with about a fiftieth!

reflecting specularly and not diffusely as in the case of a wavelength. This of course limits

of the non-resonant cavity. the efficiency of resonance light amplifiers

The reflectors in the cavity vessel 51 contain 65 prisms and also resonance light amplifiers

Prisms 69 and 71. In the cavity 58 can be plane mirrors. In the case of mirrors, however, it would be

Mirrors are used as reflectors, but in many also necessary, the mirrors in concerned

Cases are prisms to the mirrors due to the high ends of the cavity, for example in a

7 8

Embodiment 30 cm separated from each other, those angles at which one is parallel to the plane of incidence to be arranged and held parallel, and that with a polarized wave being completely transmitted (without

Tolerance of about a fiftieth of a wavelength. This reflection) and one perpendicular to the plane of incidence

can probably be achieved, although polarized wave is practically totally reflected,

of course a very extraordinary precision 5 The prism 83 is preferably designed so that

and an expensive operation would be required. on the surface 85b at the angle of polarization

In addition, the finished device would be very (indicated by the angle Θ β in FIG. 4) on the

sensitive to disturbances and vibrations of all surface 85b incident rays are refracted so that

Types, including physical accelerations, that they are approximately perpendicular to the surface 85 of the prism 83 a

Temperature changes etc. io run (or, if the parts 83 α and 83 b from a

The prisms 69 and 71 are preferably made of light-uniform pieces of transparent material,

reflective coatings on their faces 74 to the plane separating these parts),

A second prism 86 is located on the other

Light is normally lost as it is out of phase at the end of the cavity 82. The prism 86 is a right-

or something is misdirected and not related to the 15 angled triangular prism that is so arranged

main standing wave in the cavity is that a triangular area in FIG. 4 is visible.

coherently added. The edges of the three prism faces 86 are shown in FIG. 4th

The surfaces 73 of the prism 71 reflect normally visible. They are those of the reflective surfaces

wise practically one hundred percent. An output from 87 0 and 81b and the end face 88.

the cavity (or in the case of operating as 20 The face 88 is also at an angle

Amplifier also an input) can be arranged through or to the longitudinal axis of the cavity 82, the

both of the surfaces 72 of the prism 69 may be provided. equals the polarization angle for the material,

The surface 72 can be made partially transparent from which the prism 86 is made. That angle

by placing a material on or near the surface indicated by Θ β.

is applied which has an index of refraction, 25 The prism 86 is preferably cut so that it does not differ from the index of refraction of the prism on the surface 88 with the angle of polarization sufficiently to be refracted total reflection on incident light rays so that they are the inside to surrender. A desired one can thus impinge on the reflective surfaces 87 ″ and 87 b with a part of the angle of approximately 45 ° that strikes one or both surfaces 72. Light to the outside of the cavity due to the angle of incidence of the rays on which it is admitted. If the device, however, as surfaces 85 b and 88 of the prism 83 and 86 in F i g. 4 amplifier is to be used, whereby an input serves the optical system in FIG. 4 not only to make the passage necessary, the same path or a closed path can be used for light rays, similar path as an input for the light amplifier but also to reflect the light that is used. 35 has other than a certain polarization.

At the same time, the problem of partial reflection of the

Amplifier with polarization _{angle prisms Light practically passes through from the} face of the prism

Another embodiment of a resonance light - the orientation of these surfaces is switched off. Amplifier is shown in FIG. It has a window89 in the cavity vessel81

Lumen vessel 81 which is seen with a working medium 82 40 in order to allow light to pass through, which is filled of the type already described. In the vessel surface 88 of the prism 86 is reflected. From the above 81, a prism 83 is provided. This prism consists of explanation, it can be seen that normally no two parts 83 a and 83 b. Reflection of light generated in the cavity from the

The part 83 a of the prism 83 is a triangular surface 88 takes place because there is a closed path 90 ° prism, the triangular surfaces of which in FIG. 4 not 45 (and amplification) only visible for light of certain polaris are. A reflective surface 84 of the prism results and this light completely through the mas 83 is shown in FIG. 4 shown. The other reflective surface 88 is allowed through. However, to one The animal face lies on the rear side of the prism to provide exit from the cavity 82, the and is not visible. One edge of the end face surface 88, for example, by adding an over 85 « of prism 83 is also shown in FIG. 4 shown. 50 trains can be made partially reflective. A

In practice it may be desirable, the output can also be provided in that Prism 83 from a solid piece of transparent the prism 86 is used with an angle that produce rentem material, in a soft case none differs slightly from the polarization angle Area 85cr, which is shown in the figure, and thereby a low reflection of the polarized were. However, the overall effect would be the same. 55 caused light that is generated in the cavity 82.

A second part 83 b of the prism 83 is also designed as In some cases it may be desirable to form the red triangle-shaped prism. In this case, the flexibility of the surface 88 is to be controlled, which is a triangular surface in FIG. 4 visible. Although the output of the hollow part 83b of the prism 83 would be controlled as a right-angled triangular space 82, among other effects. This can be done by a rotating prism in FIG. 4, it is not necessary to secure the prism 86 in such a way that the right-angled corner of the prism is exactly formed so that the angle of incidence of the rays is formed with the forehead, since this angle is actually not a right surface 88 by turning of the prism 86 must be an angle about an axis. can be controlled perpendicular to the plane of the drawing.

The end face 85b of the prism 83 is in a

Angle to the longitudinal axis of the cavity 82 assumes that F i g. Figure 4 shows a preferred embodiment of one arranges which angle approximately equals the polar optical system shown in the light versation angle (according to Brewster's law) restorative device according to FIG. 3 or other of prism 83 is. The polarization angle is the resonance light amplifier can be used and

909 531/282

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At least one of the surfaces 135 can be provided with a desired reflection from the end face of the prism coating of a medium which gives one and at the same time provides a polarized output refractive index between that of the prism 134 and the signal passing through has a filtering effect within the atmosphere in which it is placed, whereupon cavity 82 is obtained. Such a filter effect avoided by a total reflection on the surface 135 within the closed path within and a passage of the cavity created in the cavity 121 is made possible for the output light to be filtered through the prism 134. The signal of the light amplifier can now be seen on the basis of the fact that the prism 134 has passed through the fact that the approximately 50 ° / ₀ power loss, emerging light through Reder results from a polarization outside, io flexion and refraction are divided can. In practically avoided. The optical system in some cases may be desirable. If there is F i g. 4 also makes it possible, although the reflectivity is desired, to constantly control practically the entire output of the surface 88 and thus to guide the beam in one direction. Prisms can be provided in order to amplify the various. In addition to the advantageous usability in reso- 15 output bundles by reflection or refraction, the optical system can combine according to and practically in the same direction as shown in FIG. 4 lead advantageously for other purposes.

be used when a light resonator such. B. An optical filter 137 can be in the light path

is used in a Fabry-Perot interferometer. are brought between the prisms 131 and 134,

20 µm light of a different frequency than that for that

Resonance light amplifier with internal discharge mode of operation of the light amplifier selected from-The Process to excite the atoms within to separate. Especially if such a Verdes Cavity can be operated more strongly than an oscillator on resonance light amplifiers, an atomic one can be applied as shown in FIG. 5 is shown. A transition more likely than that elongated cavity vessel 121 is provided, which is present 25, which generates the desired light frequency, has closed ends 122 and 123. Purpose- Such a transition would cause an oscillation moderately, at least one of the ends is, as with- lower input power than that for the desired one for example 123, translucent to light of the frequency, generate oscillation required. Such parafor which the amplifier is designed. In the case of the sitic vibrations must be suppressed. The side walls need not pass through cavity 124, with the exception of Clear be like in the cavities described above, vibrations in different vibration spaces, because here there is no need to form at the same time and would not be in everyone Carry out light energy through the walls, since fall is undesirable. Consequently, it can be desirable other facilities may be used for suggestion. be an optical filter such as 137, in The interior 124 of the cavity vessel 121 is to be attached to the cavity 124, whereby with Ausmit filled with a gaseous atmosphere, which would take off the desired frequency of light Reservoir 125 can be supplied, strengthening for all frequencies below the point over one controlled by a temperature controller 127 is reduced, which is responsible for maintaining a Heating coil is heated. As is already required in connection with vibration.

with other embodiments of the device 40. Another and diverse use for a filter (such as the filter 137 in the vessel 121, which is shown in FIG ken all parts 125, 127 together with the furnace 130 F i g. 5 is shown) is made for the purpose of Hermit adjustable temperature, which gives the cavity 121 rearrangement of polarized light at the output of the light, that the pressure of the stimulable medium in the amplifier. Obviously, the introduction of a Cavity is kept at a suitable value. 45 polarizing filter in the closed path in the Preferably, the interior 124 is provided with a gas-light amplifying device with the occurrence shaped atmosphere filled with a mixture of losses for light except for those Contains sodium and mercury or is associated with a polarity to which the filter is permeable. other mixture of elements with the help of which these losses largely prevent the gain Efficiency of the stimulation of the affected atoms 50 light other than that of the desired polarity, to a desired energy level with the help of and in an oscillator, the generation becomes itself Clashes of the second kind are favored. The sustaining vibrations with the exception of general theory according to which an advantageous loading prevents light of the desired polarity. Settlement distribution of the energy levels of an element It can be seen that in the device in FIG. 5 no separate gas discharge lamp is provided due to collisions of the second type with a 55, other element can be generated, has already been mentioned about a light excitation of the medium in the hollow and will not be repeated here. That space to create. Instead it becomes an entoptic The system of the establishment in FIG. 5 is similarly charged directly in the vessel 121 with the help of Elekdem already described by generating two prisms 131 trode 127 which are connected to an energy source 123 and 134 are connected to 60 extending at right angles to one another via lines 129. Cathet surfaces 132 and 135 as well as potential forehead electrodes 127 in FIG. 5 are within the area 133 and 136, where the breaking vessel 121 is arranged and can be fed Edges are perpendicular to each other. As has already been mentioned for either a direct current or a low frequency, the end faces 133 and 136 are to result in pre-discharge. However, it is not necessary preferably with a coating to reduce the 65 that the electrodes are arranged in the cavity, Reflection coated so that practically all of it to create a discharge in the cavity. Reflection by internal reflection from the surfaces 132 For example, electrodes outside the hollow and 135 takes place. space can be used, which is made possible by aluminum foil

11

Od. The like. Are formed in order to cause a high-frequency electrical discharge in the cavity 121.

Other atomic energy levels that can be excited by a discharge

In addition to the excitation of the Na (6 P and 7S) levels by collisions of the second type with metastable Hg (6 ³ P ₀ ) in a discharge in the light amplifier tube, there are a number of metastable levels that are likely to be levels of nearly the same energy stimulated in other atoms by collisions of the second kind, listed in Table I. These levels are long-lived because the electrical dipole selection rules forbid a transition via this rapid radiation process to a lower level. Metastable energy states are only given for atoms that normally form a monatomic gas - which therefore do not combine to form molecules - although others could also be used if necessary. Table I is not exhaustive, but contains the states that are most likely of practical interest. The alkaline earths zinc and cadmium cannot easily be vaporized.

Table I.

element

Sn

Pb

Be ₅ Mg, Ca, Sr, (Ba).

Zn

CD

Ed

Hey

No

A.

Kr

Xe

Marg

Tl

It appears that at least in some cases a pure He discharge is suitable for use in a light amplifier according to the invention is desirable. A similar condition in terms of captured Photons exist for the transition Na (7S - »- 3P).

Other cases of stimulation by collisions of the second kind

In addition to the optional excitation of Na (7S or 6P) through collisions with metastable

Metastable energy Ioni 21,559 energy above
Orund station 15.75 conditions State potential 13,996 2v 7.3v 12,127 4th 7.4 10.746 H ³ P ₂ , W ³ P ₀ 6.1 H ³ P ₂ , H ³ P ₀ 4th 9.39 H ³ P ₂ , M ³ P ₀ 3.73 9.00 6 ³ P ₂ 5.4 I -1 / \ A'IA 6 ³ P ₀ 4,642 2'S ₁ 20.55 ι \ 24.581 2 ³ S ₁ 19.77 J 2 ³ P ₂ " 16.53 2 ³ P ₂ " 11.49 2 ³ P ₂ " 9.8 2 ³ P ₃ " 8.30 2 ³ P ₂ " 6 ² P _3/2 0.97

Hg (6 ³ P ₀ atoms in a discharge are given in Table II other atomic metals that can be excited by colliding with metastable atoms. In any case, higher levels of the working element will fall near metastable levels of a possible carrier gas. In some cases such secondary fluorescence has already been observed by experimenters.

Table II Some clashes of the second kind

^^^ •• ■ "1 / VA ** tfVfl Ct Metastable state [ 5 ³ P _a (9.84) 1 6 ³ P ₂ Initial state Excited state Ne (2'S ₀ ) 8'D, 8 ³ D iragcrgas of the wearer of the work atom of the work atom Ed 6 ³ P ₀ (4,642v) _{T1 (6} 3p _{3/2) 1/0} different Kr (4'S ₀ ) Ed 6 ³ P ₀ (4,642v) In (5 ² P ₃ - i /) different Hg (6'S ₀ ) Ed 6 ³ P ₀ (4,642v) Hg6 ³ P ₀ "->"8'S ₀ (9.2Ov) (ZlE = 0.08v) 6'P ₁ -
I. - 4916 Ä photon Xe (5'S ₀ ) 6'S ₀ + 1899 Ä photon Ed He / 2'S ₀ (20.55v) 2 »Si (19.77v) A. 4 ³ P ₂ (11.49) Kr Xe

Claims (9)

13 14 Light amplifier transitions from the metastable probability of a good coincidence. At least three coincidences that are fairly close to the ground state are known, as Ta-In all the examples discussed so far, the belle III shows, the spontaneous decay rate of the excited state is greater than Table III than 10 "see- ¹ which is characteristic of allowed electrical 5 _{)" Kdnzidente "(} Since the excitation rate is of the order of 10 ⁵ sec- ¹ , He (3 ³ P- »2 ³ S) 3889 A ^ Cs (8 ³ P ^ ₂ <-> 6 ³ S _1/2 ) 3889 Ä it is obvious that even when using the effective 2n 3303.7A ^ Na (4 ² P _V ^ <-> 3 ² S., ₂ ) 3303 Ä seed and selective method of collisions _{Δ c; i1} -ι _Γί , S _2n " _ ^ ₂ Q 'nqc-h ο ä of the second kind the occupation of the excited to- * °' - 'state is not made stronger than that of the ground state. However, in none of these cases the overlap can be made an effect as light - good enough for a high efficiency of the amplification or emission through mutually induced excitation Illustrious examples of transitions occurring only to an intermediate state, excitation of molecules by coincident spectral whose occupation is observed at an even greater rate of the 15 lines of atomic spectra, spontaneous decay is kept lower. Every electronic energy state in a two-Es is also possible, the occupation of a long-atom molecule is split into about 50 vibrational states of livelier lower states by collisions and each vibrational state is reduced in about the second kind, to the same result 200 rotational states. to reach. 20 That is why one can consider more than 100,000 absorption. Zinc is an example. The meta- transitions from occupied states in each molecule of stable 4 ³ P levels are expected to be more than 4 electron volts on average. As expected, there is above ground state, as in FIG. 7 is shown. In general, at least one coincidence of a strong These levels do not lie in the vicinity of any spectral line of an atomic spectrum with a resonance of other metastable levels and so cannot be the transition of a given molecule. For the same reason directly by collisions of the second kind, the emission is excited by a discharge. However, higher non-metastable levels of zinc in a molecular gas can be broken down into many faint line levels through collisions with meta-. These can be excited by an external lamp made of stable krypton and xenon. The zinc atoms disintegrate very quickly from these states which are not stimulated in a simple manner. From the above explanation it follows that the states that are metastable as well as the basic combinations of monatomic substances that state. bordering on a coincidence, not very promising The rate of decay of zinc (4 ³ P ₁ ->4'S ₀ ) by Emis- are, although a light amplifier according to the invention sion of the ultraviolet photon λ - 3076 Å can be made so that it has light energy a A = 1 · 10 ^B see- ¹ . It has already been mentioned that substance can be used to stimulate another substance rates of excitation by collisions which are somewhat greater to excite with a coincident spectral line can be attainable. Therefore, on the other hand, the coincidences of a spectral should be possible to achieve light amplifier transitions directly to the line of an atomic spectrum with a resonance over ground state of zinc. It has to be: a molecule often moves in such a way that it becomes very high £ g _π 4o amount of coincidence that is necessary to use Nhigh - low «* Nhigh> - ^ z, - '· in an excitation process in a light ^amplifier Ιλ ² / (ϊο) Λ is suitable according to the invention. Substitution of the values results in Nzn (3P ₁ )> 5-10 ¹¹ Cm ³ . An example of such coincidence, as if the atoms is usable by collisions on the three excitation process is the coincidence metastable states are distributed, which require 45 of the first member countries sodium Elementary Set is with / l = 5893 A ₅ derliche zinc only 2 x 10 ~ ⁵ Torr. This is the one that coincides very closely with one of the absorption lines of the iodine vapor pressure at around 200 ° C. In the case of thallium most atoms may The construction of a light amplifier with Ausin more durable the lot 6 ² parity, metastable state Use of this kind of excitation is the same in general by a similar indirect mechanism overall 50 as that described above, with the exception are brought: either collisions of the second that the excitation lamp would be a sodium vapor type with metastable Hg or absorption of the reso lamp and the working medium in the cavity iodine radiation with 3776 Å with the following decay would be vaporized. 6 ² Pa ₂ . It should be noted that the various In this case, because of 55th types of excitation, such as excitation by reso- . _ _x nance radiation (excitation by discharge in the A (ö tt _{/ 2} -> 6 F> / ₂ ) as M see cavity) etc., in general both on the non- the density can be very high: N «a 10 ¹⁴ atoms / cm ³ or resonating as well as the resonating execution P "3 × 10 ^-3 Torr at a temperature T" A 600 ⁰ C. Toggle approximate shape of a light-amplifying means The possibility of the coincidence of two suitable 60 reversible, just like the various discussed atomic spectral lines is low. In visible and working media, near ultraviolet region of the spectrum is space claims for some three hundred thousand spectral lines of double width with only slight overlap. There are 1. Optical transmitter or amplifier, its a maximum of a thousand usable resonance transitions 65 monochromatic radiation from a gas with suitable atoms and about thirty strong atomic stimulable medium, its mare spectral lines with which they are excited by colliding with atoms, ions or molecules can. Therefore, there is about a 10 ° / ₀ sodium probability other particles to the higher level of two pairs wise related stimulable energy states are excited, the energy corresponding to one of the light frequency Amount differ so that the atoms, ions or molecules mentioned are light photons as a result of stimulated Emission during the transition from the higher to the lower level of the two energy states emit, characterized in that means are provided which generate other shocks (of a second type) to the called atoms, ions or molecules faster at the lower level of the two energy states to be emptied, and that the combination of the first bursts and the other bursts are such that a relatively higher population of said atoms, ions or molecules of the gaseous stimulable medium is generated in the higher level of the two states. 2. Optical transmitter or amplifier according to claim 1, characterized in that the other Collisions are inelastic collisions with other atoms, ions or molecules. 3. Optical transmitter or amplifier according to one of claims 1 and 2, characterized in that that the stimulable medium is such that its higher level of the two energy states is a metastable state. 4. Optical transmitter or amplifier according to one of claims 1 to 3, characterized in that that the stimulable medium is such that its lower level of the two energy states is a ground state. 5. Optical transmitter or amplifier according to one of claims 1 to 3, characterized in that that the stimulable medium is of such a nature that its two stages of the pair-wise belong together Energy states are the two lowest electronic states of atoms, ions, or molecules. 6. Optical transmitter or amplifier according to one of claims 1 to 5, characterized in that that the stimulable medium is such that the transition between the stages of Energy states an electrical dipole transition partially forbidden by the electrical dipole selection rules is. 7. Optical transmitter or amplifier according to claim 1 or 2, characterized in that the stimulable medium contains indium or thallium or a mixture thereof. 8. Optical transmitter or amplifier according to claim 1 or 2, characterized in that the other particles are atoms, ions or molecules that are in a metastable state with higher levels Energy than the electronic state and which come from another medium, the Sn, Pb, Be, Mg, Ca, Sb, Ba, Cd, A, Kr, Xe, Rn or Tl or a mixture of two or more of these contains. 9. Optical transmitter or amplifier according to one of claims 1 to 6, characterized in that that the stimulable medium is a molecular gas, the molecules of which are a halogen, preferably Iodine. 1 sheet of drawings 909 531/282