DE1622117A1 - Device for increasing the intensity of an optically generated image - Google Patents

Description

PATENTANWÄLTE Άμ§ούΰί '_& ^^ _&& 1η £ βη ₃ the 2. 2. T968 DR. ING. E. LI E..BAU. .

DIPL. ING. G. L! EBAU 0r. Lb / p Az G 6992 1 R 7 J Λ 1 7

AUGSSURG-GÖGGINGEN ^{tyai4 /}

V. ElCHaNDORfF-SIB. 10 »TEI» 33M33 _t

Society for the Promotion of Research _ '-.'.

at the Eldg. "Techn. University ) Zurich (Switzerland)

Device for amplifying the intensity of an optical

generated image

The present invention relates to a device to "amplify the intensity of an optically generated image.

There are already devices that serve the same purpose known and for example in the German patents No. 934,313; 1,020,129 and 1,114,043. One further establishment of this genus' is also in the German Patent application G 44.070 has been proposed.

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Like the earlier devices mentioned, the device according to the present invention also has at least one zone illuminated by a light source, which is optically imaged on an associated diaphragm strip by reflection on a reflective surface which is present on and together with a deformable layer is deformable by electrostatic field forces. The _k image to be amplified is imaged in rasterized form on a light electrically conductive layer ⁷ which most evocative of electrostatic field affect a deformation of the reflecting surface - enced. There is also an optical system for observing. direction of the reflective surface past the edges of the aperture strip or between the: aperture strips, if there are several. The reflective surface is expediently displayed on a projection screen, on which an image of greater brightness corresponding to the image to be intensified can then be perceived.
"By German Patent No. 1,114-043 is

it became known to an institution of the type mentioned, the photoelectrically conductive layer has an electrode grid to be assigned, · which has a group of spaced apart, electrically conductive strips, whose. Longitudinal edges orthogonal to the longitudinal edges of the diaphragm strip run, and in alternating order to one and the other

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connected to the other pole of an electrical voltage source are. Furthermore, "in this known design is photoelectric An additional grid is placed in front of the conductive layer, which is impermeable to at least certain light frequencies Has parts whose geometric configuration and arrangement of that of the strips of the electrode grid are different-

The present invention relates to a further development of the last-mentioned means and aims to alleviate the requirements g, which must be provided to an optical imaging element as one of the means of observation of the reflecting surface. '

To better understand the meaning of the present • Invention is first referred to a known embodiment to Figures 1 through 4 of the accompanying drawings described * - '

Fig. 1 shows schematically in a perspective view the overall arrangement of a known device for ■ reinforcement an optically generated image; "

Fig. 2 illustrates a light control member of the device according to Fig. 1 on a larger scale and for clarity because of its partially separated arrangement Components;

Fig. 3 shows an ingot of the second Schlieren diaphragm and represent the diffraction patterns of an opening of the first Schlieren diaphragm occurring during operation of the device;

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ORIGINAL BATHROOM *

Pig. .4 is one to Pig. 3 analog representation, which illustrates the disadvantage of the known device which is intended to be remedied by the invention.

According to Pig. 1, the intense light emanating from a light source "1" is bundled by a condenser 2 and directed onto a first Schlieren diaphragm 3. To simplify the following discussion, it is intended as a simple perforated diaphragm with a circular opening / 3 of, for example, approx. 1 diameter. a lens 4 produces at infinity an image of the illuminated opening fl of the bezel 3. After a reflection in a light control member 5, which is further explained below with reference to FIG. 2, the light beams pass through a lens 6, a combination with the lens 4 Image / 3 ^{% of} the opening β is generated in the plane of a second Schlieren diaphragm 7. The latter has an opaque bar V , which is arranged in such a way that the circular disk-shaped image β · of the diaphragm opening / 3 comes to lie precisely on it a totally reflecting plane ABCD (Fig. 2) contained in the light controller 5, described in more detail below, on a plane in the direction of the arrow iles P lying, not shown projection screen.

A deflecting mirror 9 and an objective 10 lead one of an object not drawn in the direction of arrow 0 incident light beam on a layer with photoelectric Conductivity. The latter is also a component part

00 0843/154 9

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Licbtsteuerorgaiis 5. The lens 10 is arranged so that on the layer mentioned a sharp image of the mentioned: Object creates »which can be a slide, a PiIm, an illuminated object, etc. ·. ■;

The light control element 5 has an isosceles glass prism 11 with an edge angle of 90 °. That of the. ^{: The} light coming from the lens 4 falls on the one - in FIG electrically conductive, translucent layer 13 (for example made of tin dioxide) is applied. A layer 14 of a soft medium (for example silicone rubber) rests on this layer 13, which serves as an electrode. Leaving an air gap 15 of, for example, 50 / U width, an element 16 is arranged opposite the layer 14, which element is described further below with reference to FIG g th 13 and 14 "after which it is totally reflected on the optically flat, free surface of the slice 14 designated by the letters AB CD due to the angle of incidence of 45 °. After passing through the layers 14 and 13 again, the glass plate 12 and the prism 11 the light beam continues to lens 6. "-.- .." V

In Pig. 2 the element 16 can be seen in its details «, The various components 17 to 21 are partially drawn in a separate arrangement for the sake of clarity, although in reality they are firmly bound together. The element 16 has a layer 17 approximately 1 / u thick composed of a photo-conductive substance such as antimony sulfide. An electrical grid consisting of two , in alternating sequence interlocking, comb-like grids 18a and 18b is on a plate-shaped carrier 19

L ·, ■ "■■■ -"

W arranged, the au3 insulating and transparent material

(Glass, quartz) and a thickness of 100 to 200 / u Has. The grids 18a and 18b have a family of parallel ^ electrically conductive strips on and are for example made of aluminum by vacuum evaporation. The grids 18a and 18b are in conductive contact with the photoelectric conductive layer 17. Finally, there follows an optically effective line grid 20, which consists of a series of equidistant * opaque and thin metal strip composed fc and attached to a transparent support plate 21 is. It is important that the longitudinal direction of the strips of the Grids 18a and 18b perpendicular to the longitudinal axis of the bar 7V stands. Finally, the longitudinal direction of the strips of the grid of lines 20 is opposite to that of the strips of FIG Grids 18a and 18b rotated 45 °. The two grids 18a and 18b and the grid 20 are greatly coarsened and in reality have a period of e.g.

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200 / rev. The grids 18a and 18b are attached to the two poles one electrical voltage source TI ™, such as a battery, connected. A second voltage source Uj is between the electrical conductive layer 13 and the eirjen electrode grid 18b switched on * The voltages of the sources U ^ and U ^ like

e.g. 100 volts. -. .

As has now been described in the German patent specification 1.114.043, the voltage source U ^ in the gap 15 generates an electrical PeId, the strength of which varies periodically in the direction parallel to the surface λ before ABCD and perpendicular to the longitudinal direction of the strips of the grids 18a and 18b, which Electrostatic force effects a wave-shaped deformation, called pre-deformation in the following, of the surface ABCD. The wave crests of this pre-deformation lie parallel to the longitudinal direction of the strips of the grids 18a and 18b. The additional use of the voltage source Ur increases the pre-deformation, but without its periodicity and orientation to influence.

The surface A BC D deformed in this way represents a due to " the above-mentioned total reflection is a specular diffraction grating. Thus appear in the plane of the Schlieren diaphragm 7 besides the with a flat surface A B "C D there is only a circular disk image

ß ^f their other images ß "of the same size, but different brightness. Their centers all lie on a straight line which is oriented perpendicular to the longitudinal direction of the strips of the grids 18a and 18b and with the longitudinal axis of the bar 7"

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coincides (see Pig. 1). Since the bar 7 'is not only the original picture ßV, but also all the new ones Picks up diffraction images ß ″, no light passes through the objective 8 and according to the arrow P to the projection screen. The pre-deformed surface ABCD thus remains on the projection screen invisible.

The situation is different if a bundle of light strikes in the direction of arrow 0. As in the German patent specification No. 1.114.043, the just described pre-deformation of the surface A BCD then also occurs Another deformation is added, the crests of which do not match the The longitudinal direction of the strips of the grids 18a and 18b coincide. The superposition of both deformations results in an oblique, fabric-like pattern. It shows up in those sub-areas of the area AB C D, the exposed sub-areas of the photoelectrically conductive layer 1? opposite. On the other hand show such parts of the area ABC D, the unexposed Parts of the photoelectrically conductive layer 17 are assigned, as before, only the pre-deformation.

The surface AB CD, which is deformed twice in this way and resembles an oblique, reflective cross grating, now changes the distribution of the diffraction images in the plane of the Schlieren diaphragm 7 in two ways: On the one hand, new diffraction images β ^f 'appear on both sides of the bar 7' (cf. Fig. 3, which shows the relationships in the plane of the Schlieren diaphragm 7

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on the other hand, the brightness of the images β 'and β "already present during the pre-deformation is reduced, since the light is partly ^{shifted to the newly added diffraction images} ß lfI. Since the light appears on both sides of the bar 7 ^r , turn Diffraction images β ″ ^{f can} now run to the objective 8 without being hindered by the bar, those parts of the surface ABCD which show the cross-grating pattern, ie opposite exposed parts of the photoelectrically conductive layer 17, are also shown as bright on the projection screen " ä surfaces appear.

The impetus for the present invention is now. in following difficulty:

If the light signal incident according to arrow 0 has a relatively low intensity, one will nevertheless try to obtain a bright image on the projection screen; this succeeds if the voltages IL and U ^ are made sufficiently large. According to calculations and experiments, however, the result is such a strong pre-deformation of the layer 14 * that precisely the light-r strongest diffraction images β '· and β; ^{111 have} a considerable distance (for example 5 cm) from the undiffracted diaphragm image ß ¹ . This is illustrated in FIG. 4, in which, in comparison to FIG. 5, the zone of high brightness is shifted into the diffraction images f ¹¹ , β ¹ · 'which are further away from the central image β'. Some of the diffraction patterns ß ^M, ß ^{1 '1} are already outside the opening of the objective

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If this light for the picture on your projection screen as well is to be used, so the lens must be 8 ~ have a significantly larger diameter, which can make the optical effort very expensive. The present invention now allows the striving apart of the powerful Diffraction patterns by only reducing the pre-deformation to reduce and to use a lens 8 smaller aperture without reducing the brightness of the image on the projection P screen to reduce significantly.

The device geraäss the invention has the initially mentioned structural features of the known devices to increase the intensity of an optically generated image as well. In a well-known way, it is photoelectrically conductive Layer an electrode grid assigned to which a group of spaced apart, electrically conductive Has strips, the longitudinal edges of which are orthogonal to the longitudinal edges of the aperture strip and which in alternating fe Follow to one and the other pole of an electrical voltage source are connected. The photoelectrically conductive layer is also provided with an additional grid, which has at least for certain light frequencies impermeable parts, the geometric configuration and arrangement of that of the strips of the electrode grid is different.

The novelty according to the invention consists essentially in that a second electrode grid with a bevy of

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arranged at intervals next to one another, the electrically conductive strip is provided, the number, length, orientation and mutual distances of their Irängsmittellinien like are the same in the first mentioned electrode grid and also connected in alternating sequence in the one and the other pole of a second voltage source slnd _s and that the second electrode grid is arranged at a distance from the reflective surface in such a way that it at least approximately compensates for the pre-deformation of the reflective surface caused by the first electrode grid through the effect of electrostatic field forces.

Further features and details of embodiments of the invention emerge from the subclaims from which now the following description and from the accompanying drawings, which in the Pig. 5 to 7 purely by way of example and schematically illustrate two different embodiments of the subject invention.

Fig. 5 shows in perspective and for the sake of clarity partly pulled apart the components of a light control organs which the known power control organ shown in FIG to replace the device according to Fig. 1;

Fig. 6 schematically shows the overall arrangement of a second embodiment of the device for amplifying the Intensity of an optically generated image;

Fig. 7 illustrates the light control member on a larger scale the device according to FIG. 6.

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That in Pig. 5 illustrated light control member 5a is with respect to of parts 11, 12, 14 and I7 to 21, as well as the column

tes 15 exactly, the same design as the above-described known, embodiment according to Fig. 1 and 2. However, the following differences are essential: Instead of the electrically conductive electrode layer 13 of the known embodiment, a second electrode grid is present, which consists of two cainm-shaped, _ interlocking There are electrode grids 13a and 13b which are arranged on the transparent, electrically insulating plate 12. The electrode grid 13a, 13b has a group of electrically conductive strips arranged at intervals next to one another, which alternate one and the other caramel-shaped grid The orientation, ie the longitudinal direction of the strips of the electrode grid 13a, 13b is the same as that of the electrode grid 18a, 18b. Furthermore, the number and length of the strips, as well as the mutual spacing of the longitudinal center lines of the strip windows of both electrode grids, are correct 13a, 13b and 18a, 18b exactly match. The two Git ter 13a and 13b are produced, for example, by vacuum evaporation of aluminum and connected to one and the other pole of an electrical potential _{source U "K} , for example a battery. One of the grids 13a and 13b is also connected to one pole of the potential source U ^, the other pole of which is connected to one of the grids 18a and 18b.

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Although FIG. 5 shows, for the sake of clarity, the soft, deformable layer 14 at some distance from the plate 12 and the electrode grid 13a, 13b, in reality it is in direct contact with the electrode grid 13a, 13b. Likewise, the plate 21 carrying the line grid 20 is actually directly connected to the plate 19 carrying the electrode grid 18a, 18b bound. Only between the deformable layer 14 and the photoelectrically conductive layer 17 is a gap 15, as in the known embodiment of the light control element. Between the two electrode grids 13a, 13b and 18a, 18b are so deformable splints 14, the gap 15 d ± _e light electrically conductive layer 17, while the electrode grid 18a '18b is arranged in direct Eontakt with the light-electrically conductive layer 17 and in this maintains an electrical field> the second electrode grid 13a _f 13b is arranged on the side of the reflective surface AB CD facing away from the photoelectrically conductive layer 17

The mode of operation of the light control device described, that in the device according to FIG. 1 instead of the known Organ 5 is used, let as follows i

As long as the voltage sources U ^ ,, tl. ^ And Ü _{K are} switched off , the free surface adjacent to the gap 15 is

ABCD of the deformable layer 14 even. If only the both voltage sources TJ- and Uj are switched on the surface AB 0 D is deformed like a wave, as in the Preformation is the case in the known Licbtsteuerorgan and has been described with reference to FIGS. If only the voltage source U ^ - is switched on, there is

™ in the interior of the layer 14 an electrical field distribution determined by the electrode grid 13a, 13b, which also leads to a wave-like deformation of the previously flat surface ABCD of the layer 14 due to the effect of electrostatic field forces. In general, this deformation is different from the aforementioned pre-deformation, what their amplitude sawn ² encounters. On the other hand, the distance between two neighboring wave crests, ie the period of the deformation, is the same as in the case of the pre-deformation, which is a consequence of the correspondence of the

fc mutual spacing of the longitudinal center lines of the electrode strips both grids 13a, 13b and 18a, 18b is *

When all three voltage sources Um, Uj- and Uj, are switched on are, the result is a superposition of the two described deformations of the area ABC D. The resulting total · ^ deformation is generally again wave-like, with your Amplitude can be larger or smaller than the amplitude of each of the partial deformations. If you move the plate, for example

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with the electrode grid 13a, 13b arranged thereon in the plane of the plate 12 and in a direction perpendicular to the longitudinal direction of the strips of the grid 13a, 13b, the resulting overall deformation of the surface ABCD is reduced to a minimum and maximum, calculation and experiment show. that a shift by half a period is necessary to get from a maximum to a minimum total deformation or vice versa. The position of the plate 12 is now chosen so that the total deformation of the area A BC H is minimal - afterwards, by suitable choice of the ratio of the electrical voltages of the two voltage sources U _n , and U ^ the size of the total deformation can be "further" The remaining deformation consists of weak wave-like bending of the surface AB CD, which has a · .- ■ - ■ - .- "" .- "■■. - '.... "- ■' ■ .. -

half as large a period as the partial deformations show and, what is decisive, only have a low amplitude.

Thus, the one produced by the electrode grid 18a »18b Predefarmation of area A BC D by the action the electrostatic field forces of the second, electrode grid ™ 13a, 13b at least approximately compensate. . "

By the above-described far-imparting Kompensation.der predeformation of the reflecting surface ABCD is achieved that the diffraction designated β · 'in Figs. 3 and 4

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images ,, which arise with im-exposed layer 17, ^{remain in the vicinity of the image ß 1 of} the aperture β. When light falls through the lens 10 onto the photoelectrically conductive layer 1.7, a new electrical field distribution results in the gap 15, which is superimposed over the two fields which are generated by means of the electrode grids 18a, ISb and 13a, 13b and

k of the 'associated voltage sources IL ₁ and tLr are caused. The wave-like residual deformation of the surface ABCD is then superimposed on the line grid 20 by a further deformation. In this way, diffraction images β '"falling next to the bars 7 * arise, which cause an illumination of the projection screen. These diffraction images β' ¹¹ , which are decisive for the image generation on the projection screen, remain, unlike in FIGS. 3 and 4, in the vicinity of the figure. ß 'because the pre-formation of the

* Area ABC D is largely compensated: So the " Objective 8 (Fig. 1, ^ 3 and 4) no longer have a large opening in order to capture the last-mentioned diffraction images β ″ V can. You can therefore use an expensive lens with a large Foregoing diameter, without affecting the brightness the image on the screen is affected. the

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Control of the image brightness according to the local light distribution and the intensity of the image to be intensified which is thrown on the layer 17 is determined by the compensation described the pre-deformation of the reflecting surface A BC H does not impaired. .

The above description of the mode of operation of the light control element provided with the second electrode grid 13a, 13b still needs to be supplemented. If the light of the light source successively the parts 2, 3, 4 and 12 of the device according to Pig. 1 and 5, it hits the electrode grid 13a, 13b before it passes through the deformable layer 14 and is reflected on its surface ABCD. After the reflection, the light again passes through the layer 14 and the electrode grid; 13a ,. 13b. The double passage of light through Easter, 13a ,. 13b is associated with an additional diffraction effect, which may interfere with the functioning of the light control element. To keep this disruption as low as possible, e _; It is advisable to make the width of the individual strips of the electrode grid 13a, 13b small so that the optical transparency of this grid is as high as possible. For the same purpose, it is advantageous to produce the grid 13a, 13b from a material with similar optical properties as the plate 12 has. So is suitable, for example. Tin oxide better than a metal *

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Finally, it must be examined whether the second electrode grid 13a, 15b does not give rise to a brightening of the projection screen due to diffraction effects. This is not the pail, because the strips of the two electrode grids 13a, 13b and 18a, 18b run parallel to one another and orthogonally to the edges of the bar 7 * of the second Schlieren diaphragm 7, so that the diffraction images produced by the second electrode grid 13a, 13b of the aperture / 3 also fall on the bar 7 ¹ , as do the diffraction images / 3 ^fr caused by the pre-deformation as a result of the electrode grid 18ä _f 18b. Thus, the second electrode grid 13a, 13b does not produce any diffraction images of the aperture : / 3 lying to the side of the bar 7 '. Thus, even if the electrode grid 13a, 13b is present, light only appears on the projection screen when the photoelectrically conductive layer 17 is exposed by signal light incident in the direction of arrow 0, the brightness distribution on the projection screen corresponding to that on the photoelectrically conductive layer 17. -. '

The second exemplary embodiment, which will now be explained The device according to the invention has the overall structure known per se shown in Fig. 6: A strong light source 1, for example an electric arc, is a condenser 2, which bundles the light and throws it onto a Schlieren diaphragm 23 via a deflecting mirror 22. The latter consists of several parallel, opaque ones

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bad original;

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Ingots-23 ^Γ in the form of strips that are spaced apart, next to each other and have two functions. The first object 'of the bars 23' ■ is to form strip Örmige zones that are illuminated brightly by the issuing of the light source 1 Lieht and functionally the aperture fl of the Schlieren aperture 3 (Fig. L) of the. Corresponding to the above-described first embodiment . To this. Purpose is that in Fig. 6 facing, upward side of the bars 23 'reflective. The second task of the bars 23 'is the formation of diaphragm strips which functionally correspond to the bar 7 ^{1 of} the streak diaphragm 7 (FIG. 1) of the example explained first. ;.

On the illuminated side of the bars 23 'are located a lens 4 and a Licbtsteuerorgan 5b, its training is explained below with reference to Pig-7. The light control organ 5b contains a reflective surface, which the from Lens 4 reflecting light coming into said lens means of the objective 4 and f through which the light passes twice the mentioned reflective surface of the light control member 5b are the illuminated bars 23 * back on the -now as; Aperture strips acting ingot 23 'shown. A projection lens 8 and a deflecting mirror 24 are on the unilluminated Side of the bars 23 'arranged so that they; diirch the column between the bars 23 'through the reflective surface of the Light control element 5b in the direction of the arrow P on a not

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shown projection screen. The. 23V bars work in this figure only as aperture strips that are not shown on the projection screen.

Another deflection mirror 9 and a lens 10 are used, in addition, by light rays according to the arrow 0 on a light · electrically conductive layer of the light control member 5b optically generate an image su that with the described device should be reinforced and can come from a slide, a mim or a real object, for example.

The light control member 5b has the in Flg. Aufrbäu shown 7, -welcher of known designs partially deviates Nebe ^ reitistimmung-with geinäss the LiehtsteueTOrgan "Figure 5 is with respect to the carrier plate 12 of the, electrode grid, 15a, 13V. ₁ - the light-electrically 'conductive Schicht.17, the Elektrodenrästers 18a, 18b, the carrier plate 19V of the line grid 20 and the carrier plate 21. -Auch die.Anordnung the parts mentioned in; .relation to one another is the same. Lieh did your organ according to Fig. ..5. - In contrast to that one, however, - the one is missing. Licbtsteuer-, organrgemäss Figi-7 -the prism 11 and -are between-the Elektr.odengltter 13a, 13b "and the light-conducting layer electrically ^ '.. 17 Awei electrical-insulating, elastically def ormierbare ..Sc.hichten .24: and 25 as well as a S, pi, e ^ ^ elschleht; 26 present. The ·, strength, of each, defo, nj ^ able, ..... / · SQbiicht «24, or ^ 5 _i; is .about .10O ₁ Mioron, utid, the. Layer _. even can be made of a silicone polymer with _. .,.

aiii ': ·· - "■■" ■' ■■ 'j f "

"" Si * / j: .-. Vi ---! Ι - ^ - ■■ * =

8 4 3 / ΛΛ4Λ,.

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Plasticizers, e.g. silicone rubber with plasticizers, exist and should have a modulus of elasticity between 10 and 10 dynes / cm. The mirror layer 26 has a thickness of 10% 60 Micron and consists of an in-service condition of the facility liquid substance, e.g. a metal or a metal -alloy. If the facility is at normal room temperature is to work, the mirror layer 26 can expediently from Mercury or an amalgam with a small amount, say 1% by weight of indium. All of the plates and layers mentioned The lights of the light control element are on top of each other without any space between them although in Fig. 7 some of the parts are shown separated from one another for the sake of clarity *.

The two grids 18a and 18b of the electrode grid 18a, 18b are connected to one and the other pole of a DC voltage source Um. In an analogous manner, the two grids 15a and 13b of the second electrode grid 13a, 13b are connected to a DC voltage source UV. One pole of an alternating voltage source U _T is connected to the electrically conductive mirror layer 26 and its other pole to one of the electrode grids 18a or 18b. A second AC voltage source ÜV V is connected on the one hand to the mirror layer 26 and on the other hand to the electrode grid 13a or 13b. The alternating voltages of the sources U ^ and Fr 'have the same frequency and phase position, while their amplitudes know to be different. . "■ -.-.

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The mode of operation of the device according to the I ¹ Ig. 6 and 7 is essentially as follows:

- To make it easier to understand, it is initially assumed that the voltage sources U ^ - and Uj * are not connected and the voltage of the source U ^ is zero. If no light falls on the photoelectrically conductive layer 17 according to the arrow 0, the electrostatic field between the .Elektrodenraster 18a, 18b and the κ "" mirror layer 26, which also serves as an electrode, is essentially homogeneous, if one of the band effects and the Stripe forta of the grid 18a, 18b disregards. The electrostatic forces acting on the interface I between the mirror layer 26 and the deformable layer 25 are thus the same at all points on the surface I, which is why the latter does not experience any deformation and remains flat. The fact that the voltage source U ₁ emits an alternating voltage does not change anything in this respect, either. When the DC voltage

^{w of} the voltage source Um is not zero, a locally varying j is superimposed on the described time-varying electric field, with the result that the distribution of the field forces acting on the interface I becomes inhomogeneous and the interface I of the mirror layer 26 receives a wave-shaped pre-deformation, with the Wave crests and wave troughs run parallel to the strips of the electrode grid 18a, 18b and orthogonally to the bars 23 * of the Schlieren diaphragm 23.

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During the building of the mentioned. Yordeformatipn required period of time, i.e. before the acting on the surface X Field forces due to the elastic reaction forces, the Shifts 25 to be kept in equilibrium, plant yourself Pressure waves and displacement waves from the surface I-transverse

■ away through the liquid mirror layer Z £ /. At. the arrival of these pressure waves and displacement waves, they cause a pressure distribution at the opposite interface II _; .the point ,, j for the point of the electrostatic field force distribution .at the -. Area I is analogous. As a result, the interface .11 is deformed in a wave shape in the same way as the. Interface ^ I, .the. . relatively large internal friction of defprjnierharen layers 2-4 ^ 5 Urid ensures au, _sreicbende: .Dämpfung of gegebeneEifalls occurring mechanical resonances of said layers and the mirror layer fliissigen-SSS, The. in-. _{: as} described _; dBformed: boundary surface ₁ .II of the Spier · ge! layer- 2,6 acts. as a diffraction grating for the “von. the; iicbtquelle 1 originating and ajn .der_Fläche.II -reflected light, rays ^ this. _: en, t, st, e.henden, diffraction patterns of M.euchtr & ten bar- ,. Ren .2,3 * are shifted in the longitudinal direction of the bars. no. Jlufbellen, the projection screen, ..

If through, light ray _; You will love the ..- Pileil. D to _{% of} the photoelectrically conductive layer, .l _; 7, _. An image to be intensified is generated, the exposed parts of the layer 17 cause a local change in the electrostatic field distribution

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-.24

between the electrode grid 18a, 18b and the mirror layer 26, so that another deformation is superimposed on the aforementioned pre-deformation of the two boundary surfaces of the mirror layer. The latter results in diffraction images of the illuminated bars 23 ^f , which fall laterally next to the bars and cause the projection screen to be illuminated at those points which correspond to the exposed parts of the photoelectrically conductive layer 17. Because of the pre-deformation of the mirror layer 26 described above, the centers of the useful diffraction images have a relatively large distance from the centers of the bars 23 ', which is why the objective 8 would have to have a large diameter in order to be able to fully capture the light of these diffraction images and transmit it to the projection screen . This = Kachteil can be through the second electrode grid ^"15a: 13b- avoid using the voltage sources U ^ and Ur * ■.

The effect of the electrode grid 13a, 13b and the voltage sources Bß- uffd Ilr 'on the mirror layer 26 agrees with the above-described effect of the electrode grid 18a., 18b and the voltage sources Um' and Uj- in the case of the most unpopular photoelectrically conductive layer 1? basically agree. The position of the second electrode grid 13a, 13b is selected in such a way and the ratio of the amplitudes of the ^; Weehseisspannungen the sources IL- and U, - 'set such, - dasS "-du # e ¹ ii - dl; e'^{; i} e ^? Iiektrostatasche field forces - effect ■ dasi.Elfekt'Töden-Fasiiers- 13a; ' ^: ] t31d = · the from the other Eljektrodenr-

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raster 18a, 18b caused pre-deformation of the mirror layer 26 is compensated as well as possible. Apart from the remaining deformation that does not compensate for each other leaves, then the mirror layer 26 is essentially only still deformed by the field changes caused by the; Exposure of the photoelectrically conductive Schiebt.-17 are caused. The centers of the resulting, next to the Bars 23 'falling diffraction patterns of the illuminated surfaces (| the bars are then at a shorter distance from the centers the ingot than in the case of the presence of a pre-deformation the mirror layer 26. The opening of the lens 8 doesn’t need to be so big to get the light of the capture high-intensity diffraction images and display them on the projection screen to be able to throw, which is why a cheaper lens is sufficient. ', ■

It is perhaps useful to mention that the two voltage sources IL- and Uj. ¹ therefore AC voltage sources | because the mirror layer 26 is formed by a liquid which reproduces only time-variable deformations of the interface I in a control- dependent manner from the photoelectrically conductive layer 17 also at the opposite interface II point by point. The mirror layer must therefore be kept in pulsing motion all the time. The brightness intensity of the illuminated areas on the projection screen changes periodically between zero and a maximum

BAD ORIQfWL
009943 / TiW

worth in the rhythm of the movement of the surface II. If this The rhythm is fast enough and e.g. 20 changes per second exceeds the human eye because of the inertia of the Retina no fluctuations in the intensity of the amplified Perceive the image on the screen. More details of a similar light control organ with a liquid one Leveling layer can be found in the German patent application mentioned at the beginning G 44.070 can be taken.

BAt> ORIGINAL
009843/1549

Claims (9)

- 21 -: P a t e η t a "η s ρ r ü c h e 1. Device for intensifying the intensity / of an optically generated image j in which "at least -.- one zone illuminated by a light source (I) on an associated diaphragm strip (7 ¹ or 23 ') by reflection on a reflective surface ( ABCI) or II) is optically imaged, which is present on a deformable layer (14 or 26) and is deformable together with this by electrostatic field forces, with a photoelectrically conductive layer (17) on which the image to be reinforced is in rasterized form and which influences an electrostatic field causing the deformation of the reflective surface (ABCD or II), with an optical system (8) for observing the reflective surface (A BC D or II) at the edges of the diaphragm strip (7 ¹ or (| 25 ') over, with an electrode grid (18a, 18b) assigned to the photoelectrically conductive layer (17), which contains a group of electrically conductive St has tires, the longitudinal edges of which run orthogonally to the longitudinal edges of the cover strip and which are connected in alternating sequence to one and the other pole of an electrical voltage source (U ™), and with a 9843/154 BATH additional grid (20), which of the photoelectrically conductive Layer (17) is provided. and at least for certain light frequencies impermeable parts, their geometric The configuration and arrangement are different from that of the strips of the electrode grid (18a, 18b), characterized in that that a second electrode grid (13a, 13b) with a Flock of electrically conductive strips arranged at intervals next to one another is present, their number, length, orientation and mutual distances between their longitudinal center lines are the same as in the first-mentioned electrode grid (18a, 18b) and the also in alternating order at one and the other pole a second voltage source (Ug-) are connected, and that the second electrode grid (13a, 13b) is arranged at a distance from the reflective surface (A B C D or II) in such a way that he through the action of electrostatic field forces that of the first Electrode grid (I8a, 18b) caused pre-formation of the reflective surface (A BG D or '. II) at least approximately compensated. . 2. Device according to claim 1, characterized in that that the second electrode grid (13a, 13b) on the from the first Electrode grid (18a, 18b) facing away from the reflective surface (A B C D or II) is arranged, 3; Device according to claims 1 and 2 * characterized in that that between the first and the second electrode grid <18av 18b or 13a, 13b) the photoelectrically conductive one 009843/154 9
BAD ÖäfGfNAL Layer (1.7), the deformable layer (14) with the reflective Area (A B G D) and a between the photoelectrically conductive Between the layer and the reflective surface (15) are arranged. · 4 * device according to claims 1 to 3, characterized in that that the first electrode grid (18a, 18b) and the photoelectrically conductive layer (17) in conductive contact with one another on a first transparent plate (19) from electrically insulating material · are arranged, while the second electrode grid (I3a, 13b) and the deformable layer (14) on one second transparent plate (-12) made of electrically insulating material are attached, wherein the two electrode grid (18a, 18b * and 13a, ■■ 13b) are located directly on the facing sides of the two plates (19 and 12), which in the Are spaced from each other. . 5. Device according to claims 1 to 4, i marked thereby characterized, that a third voltage source (U ^) on the one hand to a pole of the first-mentioned voltage source (GL ₁₎ and ■ the other hand aer to one pole of ₀ second voltage source (Up / · ) connected is. . 6. Device according to claims 1 to 5, characterized in that that the reflective surface (II) in a manner known per se on one made of electrically conductive material 009843/154 3 Layer (26) is formed * which is deformable together with the deformable layer (24 or 25), and that a third electrical voltage source (Ut) is connected on the one hand to a pole of the first-mentioned voltage source (U _T ) and on the other hand to the mirror layer (26) is while a fourth electrical span. voltage source (Ut- ') on the one hand with a pole of the second voltage source (Ug) and on the other hand with the mirror layer (26) in connection (Fig. 7) - - . ': ■■'., '■' ..: '■ :: ■' ■■ 7. Device according to claims 1 to G, characterized in that the mirror layer (26) is formed by a substance that is liquid in the operating state of the device and is located between two electrically insulating, elastically deformable layers (24 and 25), and that the Third and fourth voltage sources (Ut and ÜV ¹ ) are alternating voltage sources whose alternating voltages have the same frequency and phase position. 8. Device according to claims 1 to 7, characterized thereby " shows that the first electrode grid (18a, 18b) and the ■ photo-electrically conductive layer (17) in conductive contact with one another are arranged on a first transparent plate (19) made of electrically insulating material, during the second electrode grid (13a, 13b) on a second translucent Plate (12) made of electrically insulating material is attached, the two electrode grids (18a, 18b and 13a, 13b) directly on the facing sides of the two 0098Λ3 / 154 BATH Plates (19 and 12) are located, which are spaced from each other are, and that the mirror sheet (26) and the two deformable Slid (24 and 25) between the photoelectrically conductive Layer (17) and the second electrode grid (13a, 13b) lie. . . ^ 9. Device according to claims 1 to 8, characterized in that the second electrode grid (J3a, 1 ^s 3b) is at least partially transparent. ^