DE2036674A1 - Thin window image acquisition and recording tubes - Google Patents

Description

PATENT LAWYERS .2036674 Dipi.-chem. Dr. D. Thomsen oipi-mg. H. Tiedtke
Dipi.-chem. especially burning MUNICH 2
VAL 33
TEL. 0811/226894
235051
CABLES: THOPATENT
TELEX: TO FOLLOW Dipi.-ing. W.Weinkauff FRANKFURT (MAIN) 50
FUCHSHOHL 71
TEL, 0911/61 «63

Answer requested after «Please reply toi

8000 Munich 2 July 23, 1970 T 3753 / case PG25-7OO9

Matsushita Electric.Ind. Co., Ltd.

Osaka / Japan

Thin window image pickup and recording tube

The invention relates to a thin window image pickup and recording tube in which a through a image-bearing object modulated light beam is reflected by a reflector in such a way that it is in a substantially to eggs

.Center line of a split screen (slot-shaped target) vertical Direction is aligned and directed to photosensitive organs, which are located outside the bulb of the tube are »whereby-optical images not only in an ordinary But recorded using a single way

Unity to be absorbed in a new way.

006865/1369

Heretofore, a variety of cathode ray tubes have been used Recording purposes developed in which an electron beam is converted into a light beam using luminous materials will. The resulting light beam acts on a recording ne » medium without resorting to the use of a lens or other optical systems. A fiber optic cathode ray tube and. a thin window cathode ray tube are two of the representative ones Devices advantageously used to implement this scheme used in fiber optic cathode ray tubes Experiments carried out to make the recording and recording more optical To enable images in one and the same tube unit.

According to a practice used with the fiber optic tube it has been proposed to place a translucent reflector or semitransparent mirror between the ends of the optical fiber element set. Then · the light that comes from the one with an electron

ray-irradiated luminous material is sent through the P-.ichtransparent Reflector and is transmitted to an object bearing optical images. Then the light modulated by the object returns back into the fiber optic element. That once through the element Light that has passed through is aligned a second time perpendicular to the translucent reflector and then becomes more sensitive to light. Organs led. Another representative practice is to. ι to divert a part of the light to the light-sensitive organs, so that the neighborhood, the connection of the fiber optic element with the "! image-bearing object escapes. -

These known practical examples exist j 009885/1969 ί

however, there are problems in that the optical fiber element, which in turn is complex in structure, becomes more complicated by the use of the image pickup mechanism. This leads to a considerable reduction in the. Signal-to-noise ratio (ratio S / N of the signal S to the noise N) of the image transmitted with it. Further, the optical fiber element is extremely expensive and requires sophisticated techniques for manufacture.

The invention is therefore based on the object of a to create a new thin window arrangement for recording and It is used to record an optical image. This object is achieved

'»■■. · -
through a transparent thin window which is firmly adhered to the transparent part of an evacuated bulb of a cathode ray tube and has a screen (target) in the form of a slit, through a fluorescent layer which is formed on the inner surface of the thin window and which luminesces when it is irradiated by an electron beam, through light guide members arranged inside the transparent part to "guide a light reflected from an object arranged in firm contact with the outer surface of the thin window in a direction perpendicular to the center line of the split screen, and by light detectors arranged sideways from the transparent part in order to detect the guided light outside this arrangement.

The invention is illustrated below with reference to a schematic Drawing explained in more detail on several exemplary embodiments.

009885/1969. ·:. BAD OFNGiNAL

demonstrate:

Fig. 3 is a view showing the overall construction of an example of the existing thin window recording tube represents

Fig. 2 is a schematic illustration of the principle of the recording of the thin-window tube,

3 shows a schematic illustration of the principle the image recording of the thin-window tube,

Fig. M - a «longitudinal section of the split screen, wherein in

enlarged scale, a * thin window arrangement or a significant part of erfindungsgemä- \ _t 'SEN image recording and Aufzeichnungeröhre

is shown; !

Figures 5a to 5d illustrate the image recording of modified forms of the invention Light guide organs or: devices where 5a shows an example in which the reflector has a uniplanar beveled surface, 5b shows an example in which the reflector has a biplanar beveled surface, Figure 5c shows an example in which the reflector has a parabolic surface and Figure 5d has a Example shows in which the reflector has an elliptical

has a ptical surface,
009885/1969

Fig. 6a to 6d different »arrangements, which for the fixed • position of the guided light beam can be used, 6a showing an example in which a light-sensitive material rests against the side end wall of the thin window arrangement, 6b is a sectional view of a thin window arrangement Figure 6 shows using a pair of lenses and a photomultiplier, Figure 6c is a bottom end view " Fig. 6 shows the thin window arrangement and Fig. 6d shows an example in which a combined lens and two photomultiplier units are provided on each side of the assembly to accommodate images to be able to record an object of greater width,

Fig. 7 is a block diagram of a preferred exemplary "■ approximate shape of an electric Schaltungsanord- (dung for the inventive thin-window recording or recording tube.

As shown in Fig. 1, has the conventional thin-window recording tube 10, as usual, an evacuated envelope, an electron gun 12, a thin window assembly 13, a base IU, focusing bodies 15 and deflector means 16 hit the Bezugezjjffer 17 is the Path of an electron beam sent by the electron gun.

ι ■ *

'j. ORIGINAL INSPECTED

If the beam 17 has a split screen (slit-shaped, Target) of the thin window arrangement 13 reached and in the external direction is scanned, the electron gun 17 emitted by the electron gun 12 is moved by the focusing and deflecting members 15 or 16 focused and deflected in a sufficiently small point beam. The electron beam bombarding the split screen brings a fluorescent material applied to the screen, for example phosphors, to glow. The light developed in this way then irradiates an object or a sensitized pane (nxcht shown), which is arranged in firm contact with the foremost end of the thin window assembly 13.

In Fig. 2 a longitudinal section of the screen ^ _n is an enlarged scale, the thin-window arrangement 13 illustrates the Aufzeichnungrröhre shown in FIG. 1. As shown there, the electron beam 17 guided into a river with the diameter d irradiates a fluorescent layer IS ₉ which is applied to the inner surface of a thin window 18 made of a suitable transparent material such as glass or mica, exists so that the fluorescent layer

19 is made to glow. Light rays 20 emitted in this way by the fluorescent layer pass through the thin window 18, as shown by arrows in solid lines. If then the angle OG (angle of incidence) of the direction of the light rays

20 with respect to the direction perpendicular to the surface of the thin window 13 line iat small, reach the light rays 20 through the -

, 009885/1069

-IJ-

thin window 18 and irradiate an object or a sensitized Disk or foil 21 with an intensity which corresponds to that of the initial electron beam 17.

If with η as. Refractive index of the material of the thin window 18 in relation to air or vacuum is now the value OO _q (/ Critiacher angle), which is derived from the equation:, f

was derived, the above-mentioned angle of incidence C \, over-

below, the rays of light 20 from the surface (the! outer surface is exposed to ambient air) of the thin FEN ι sters 18 totally reflected, the isti held in contact with the sensilibierten \ .Scheibe 21, the light rays are prevented from so die.Scheibe 21 to reach. It follows that only the part

009885/1969

of the rays 20, which are shown with the diameter D in Figure 2, the disc 21 can reach. If the thickness of the thin window 18 is now equal to t, we get:

D = d + 2t. tanöO _c , (2);

as in Fig. 2 emerges. Thus, the value D is determined exclusively by the values d and t and the value cL _c , which is inherent in the material forming ^{the window 18.}

From the preceding analysis it follows: although the light rays 20 in conventional thin-window tubes are diffuse light rays is the deterioration in the resolution of the sensed shit. be 21 saved images within a certain area limited. Furthermore, experiments have shown that the coefficient of optical contact of the fluorescent layer 19 with the inner surface of the thin window 18 is smaller than approximately °, 1; this means that the fluorescent layer 19 is less optical Contact with the thin window 18 is located. This also means that the light rays 20 come from an optically less dense environment (Vacuum or air) get into a dense material (which can for example be glass) and that the light rays 20 from the inner surface of the thin window 18 are also not totally- ^ reflected · - · · ,, <. Therefore, if a major part of the light rays within the range of D can reach the sensitized disk 21, can use the entrance light with increased effectiveness compared to the existing ones Tubes are used in which a Lins.e od / the like. is used.

009885/1969

As stated above, the invention brings about an improvement in the customary thin-window external oil rotors and achieves high resolving power and excellent light transmission efficiency, so that the recording becomes clear not only for storage but also for image acquisition can be used. The thin window tube according to the invention brings an increased signal to noise ratio or S / N ratio, since the part of the unnecessary light is totally reflected and prevented from doing so will get to the sensitized disc.

In FIG. 3, which is used to explain the principle of image recording work of the thin-window tube according to the invention; on an enlarged scale, a sectional view of a thin window assembly 13, which is substantially the same as that shown in FIG. In Fig. 3, the reference numeral denotes an object provided instead of the sensitized layer 21 according to FIG. 2 or an exne manuscript copy which carries optical images. One Area 22a of copy 22 corresponds to area D of the sensitized Disk onto which light rays 20 reach, as shown in FIG. 2. The surface 22a of the copy can therefore be regarded as a source of diffuse light.

In detail, an electron beam of a certain intensity irradiates the surface 22a during the image recording session, so that light rays 23 emanating from the source or surface 22a of diffuse light have an intensity which is determined by the strength or blackness of the pattern of the image on the surface 22a . It follows that only the part of the light rays

009885/1969

2035674

- ίο -

23 from the surface 22a, which is represented by the reference number H in FIG is, can get through the flenne window 18, as is results from the preceding explanation with reference to FIG.

Because the copy 22 and the thin window 18 from each other can be optically isolated, v / ground those reflected from the surface 22a and intensity-modulated light rays 23 are not totally reflected.

If a suitable photosensitive element (not shown is provided within the area H, could therefore from a purely theoretical point of view, the images on surface 22a are simple by finding the rays. 23 are absorbed. The Be However, rich H is so small that it is practically impossible to remove the fluorescent layer 19 and the photoelectric element therein to accommodate special area. The range H is expressed mathematically with the following equation:

H = d + Ut · tan CKf ', . ... . C3>

- similar to area D of equation (2). _{If then Q is} substituted for the variables'd, t and CL .'d = 10Ou, t = 100 and cLt _c - ^ ^j (for the case that the thin window is made of glass), H results with only

According to the invention, therefore, the part of the light rays becomes 23, who has returned to Area II, through a suitable one Reflector aligned in a direction that is essentially

00988S / 1969

. ■ 203S67A

to the direction of the initially emitted electron beam. That Light aligned in this way is transmitted to light-sensitive organs, which are arranged outside the piston of the tube to convert optical signals into electrical signals, the at the common thin window tubes encountered difficulties overcome can be.

Fig. H. shows a further enlarged sectional view • an advantageous embodiment of the thin window arrangement 13 of the thin window tube according to the invention. Reference numeral 24 in FIG. 4 denotes a metal screen (support metal) which consists of a metal such as Al, Au or Ni, which has been applied to the inner surface of the evacuated piston 11 by vacuum evaporation. The metal screen 24, which has a reflective surface, is intended to prevent the light emitted by the irradiation with electron beams from the fluorescent layer 19 from reaching the photosensitive organs without being modulated by the images on the copy 22 a and from reducing the S / N ratio. The metal screen 24 also serves to intercept the light rays emitted by such an impermissibly shaped layer 19 if too much luminous materials are applied to part or parts of the inner surface of the bulb during the manufacture of the thin-window tube 10. If necessary, the reflection can also be obtained in other ways, for example by taking advantage of the total reflection on the inner surface of the piston or by forming a dielectric film. .

With.de * reference number 25 is another metal screen,

909186/1364.

2035674

.der usually also arranged in a conventional cathode ray tube and through which an electron beam passes, but light rays. 20 (Fig.2) can be prevented in the Piston to arrive. The reflective surface 24 is as shown, inclined at an angle θ from the direction perpendicular to the surface of the thin window 18; this angle 0 is determined such that the light 23 is directed in a direction which is substantially perpendicular to that Direction of the center line of the split screen and in which the

ο The electron beam was initially sent out (preferably 45th).

The evacuated flask and the thin window 18 can be kept optically without contact with each other, as can be seen from the space 26, the flask and thin fensf ^ r.18 separates, so that the outer or; ^ _O pi _es eitenfläche of the thin window 18 because of the low optical contact between the fluorescent layer 19 and the thin window 18 total, reflected light is possibly further totally reflected on the inner surface of the thin window 18, whereby the S / N ratio improves can be. It should be noted, however, that there would be virtually no measurable deterioration in the S / N ratio even if the space 26 between the thin window 18 and the fluorescent layer 19 were filled with glass or a suitable adhesive filler.

This can be explained by the fact that the fluorescent layer 19 and the thin window 18 are only in 10% optical contact with one another, as stated above, and that, only one small part of the light on the outer surface of the thin window

009885/1969

ORIGINAL INSPECTED

2035674

18 is totally reflected and directed back into the tube.

The principle of the image recording of the thin-window tube according to the invention is explained below with reference to FIG. As stated above, the electron beam radiates with a. essentially constant intensity during image acquisition, so that the fixed on the side surface of the thin ferister arrangement Light contributes most to the light rays 23, the intensity of which is intensity-modulated by the images on the surface 22a would. * ■> ·.? ■ The in Fig. 4 at an angle of incidence,

which is smaller than qL> , light rays 23 going upwards are through the gap 26 into the bulb. reach. Therefore, the loss of the light rays 23 caused by the total reflection is practically negligible if the thin window 18 and the piston are evacuated. - are optically isolated from each other. The resulting .Lichtstrahl 23 are then reflected by the reflector 24 or light guide members and in the lateral direction. device in Fig. 4 deflected. Therefore, if one or more suitable photosensitive members are arranged in the lateral direction, \ the light beams can be Richtung.festgestellt this: wherein DIE photosensitive bodies, if desired, be easily handled by I the outside (outside the evacuated envelope ') kön- i nen. ■!

From the foregoing detailed description, it can be seen that with the thin-window image pickup recording tube according to the invention, the following advantages can be achieved: no irregular configurations of the optical fiber elements and no

009885/1969

2035674

-Ik-

Surface noise, a satisfactory S / N ratio that is fully sufficient for all practical purposes, and an increased efficiency, with which the luminescent light is used.

Figures 5a to 5d. illustrate examples

of light guide organs that can be used in the thin-window tube 10 according to the invention. The light guide member shown in Fig. 5a is formed in such a way that part of the metal screen or reflective surface 2k is beveled in a uniplanar manner. The slit part of the reflective surface 2k may also be beveled slightly in order to guide the main part of the electron beam through the slit screen, even if the slit part is made quite rough. This measure is taken because the width of the slit screen is only 100 yu and often cuts off a substantial part of the incoming electron beam. The thickness t (for example 100u) of the thin window 18 is so small compared to the thickness (for example 10 mm) of the bulb wall that it can be assumed that the light rays 23 mentioned come approximately from a light source 0 in FIG. 5a. The rays of light are assumed to run in the direction of the arrows,; as is the case with a conventional reflector if it is assumed i that an imaginary light source 0 is located at the position shown. *:

In Fig. 5b is another form of the light guide member £. shown that it has biplane beveled reflective surfaces, with part of the reflective surface at suitable angles. . .. double '«- - - * - · is double beveled because

009885/1969

2025674

the light rays emitted from point 0 are larger the angle of incidence will be distributed in a smaller amount. The function of the light guide member shown here is essential same as the one described with reference to the example shown in Fig. 5a, so that repeated explanation is not necessary.

In Fig. 5c, a further light guide member with a parabolic reflective surface is shown, in which f the focal point F of the parabolic surface 24 is so arranged is that the rays of light traveling in the lateral direction can be focused. In Figure 5d. is the reflective surface 2Kl · elliptically shaped, so that the same result as with of the reflective surface of Fig. 5c can be obtained if the focal point F is appropriately arranged.

• ·

The in the thin-window tube according to the invention .10 ver ' reversible light guide element is not limited to those shown and j limited cases, but includes every amendment so far the light beams 23 in one to the direction of the electron beam perpendicular direction can be effectively aligned.

Figures 6a to 6d illustrate examples of the method of detecting the guided light rays. In Fig.6a a photoconductor material acting as a light detector lies on the outer side surface of the bulb '', whereby the intensity-modulated Light rays are converted into electrical signals. The photoconductor material 27 can either be placed directly on the piston

009885/1969

ORIGINAL INSPECTED

20 356 74

or rest over a third layer (not shown) which is covered on its outer surface with the photoconductor material, so that this "matth layer together with the photoconductor material is complete can be removed from the piston for repair purposes.

Figure "6b and 6c show v / urther examples of _T" method for detecting the guided light rays by convex lenses through which the light beams are focused while they are guided; Fig. ' Figure 6b is a sectional view and 6c is a bottom end view of the thin window assembly of Figure 6b. As. As shown, the light detectors can have a pair of lenses 28 and a pair of photomultipliers 29. The lenses are preferably Fresnel lenses 2 8, · providing an increased focusing effect, because the gap portion of the evacuated envelope is long, for example, about 20cm, as shown in Fig. 6c ersieht lent *. If further, a pair of photocopiers 29 on either side of the piston. is arranged, the electron beam can be controlled so that it is aligned with the center line of the slit screen, as will be explained in detail with reference to FIG.

The evacuated piston and thin window 18 of Fig. 6b can be arranged in the manner described below be. As mentioned above, it is important that 'the piston. and the thin window 18 is hermetically sealed, are. In order to practically meet this requirement, there may be, for example 180μ thick spacer in the split screen, the thin one

00988 S / 1969

.2035674

window arrangement 13 be used, so that the width of the split screen is firmly maintained; an adhesive fritted glass 30 may be attached to the marginal edge of the end surface of the evacuated piston; the edge can be at a suitable angle, as in Fig. 6 b, notched or. be graded.-. ' .

The thin window: 18 is then placed on the fritted glass under pressure. · "

there is practically no difficulty in meeting Settlement of the thin window arrangement 13 with the piston in this way as a result of which the production of thin-window tubes with improved Efficiency is enabled.

6d illustrates a method for separating Focusing the guided light beams using a combined Fresnel lens 28 and two photomultipliers 29 placed on either side of the envelope; this procedure is especially suitable in the event that. an evacuated flask with | an unusually long slit screen is to be used.

Fig. 7 shows a block diagram ₉ showing an advantageous electrical circuit arrangement suitable for use in a facsimile apparatus employing the detection device, high-speed monitor image pickup and recording tube. The circuit arrangement - ·· has a receiving unit, transmission unit, and balance unit 31, which are used for automatic regulation of the. precise adjustment of the electron beam perpendicular

serves to Abfcaetweg. As shown, the electrical switching gear occupies

009885/1969 originally inspected

2035674

arrangement _t 'is usually an image intensifier 32 _s an amplifier 33 for the deflection coil, an amplifier 34 für'die Fokussie = · loading coil, a Detektore.mhe.it 35 ₈ a receiver amplifier 36 _s amplifier 37 and 38, for reinforcement, the power supplied from the light detectors Input signals _s for example a pair of the two photomultiplier units s> a comparator unit 39 ₉ a transmitter amplifier 40, a _{mixer unit 4I 3} a synchronization unit 42 and a modulator unit 43. The amplifiers 37 and 38 and the comparator unit 39 represent the balance unit 31 in cooperation with the two light detectors are "On the other hand, the receiver unit from the video image amplifier 32 _s the deflection" more 36, while the transmission amplifier by the transmitter amplifier '4Oj 41, the synchronizing unit _t, and the mixer unit 42, the modulator unit 43 formed amplifier 33, the detector unit 35 and the Empfängerve3? »

The circuit arrangement shown in FIG. 7 operates in the manner described below.

When receiving the electrical signals for recording, the receiver amplifier 36 amplifies the received signals in different ways Intensity, and the signals thus amplified are then sent to the video image intensifier 32 via the detector unit 35 created. The output signals of the image intensifier 32 control the Intensity of the electron beam emitted from the electron gun 12. The electron beam is through the focusing organs 15 merged into a sufficiently thin point beam that

0Q983S / 1963

203 & 674

after is deflected by the deflecting members 16 and the slit screen of the thin window arrangement 13 is scanned. This scanning signal is through the detector unit 35 to the amplifier 33 synchronously with supplied to the signal supplied by the unit 39.

In the transmission of image signals for image recording, on the other hand, an electron beam regulated to a constant intensity by the image intensifier 32 is emitted from the electron gun 12. Then the light reflected from an object bearing optical images and modulated in intensity by the strength or blackness of the images is introduced into the photomultiplier 29 or other similar light-sensitive organs. The "electrical signals" supplied by the photo managers are passed through the amplifiers 37 and 38 for amplification. The output signals of these amplifiers are then transmitted via the comparator unit 39 to the transmitter amplifier 40. As shown, two light-sensitive elements are used; However, only one can be used, in which case the position of the electron beam cannot be automatically controlled. The electrical signals amplified by the transmitter amplifier HO are then fed to the mixing unit 41, where they are mixed with or mixed with the signals which are supplied from the synchronizing unit 42; <{Le resulting superimposed signals are converted by the modulator unit 43 into a transmission wave.

The balance unit 31 works in such a way that the comparator input for both image recording and image recording

0 0 9 8 8 5/1969

2025674

39 compares the signal voltages supplied by the amplifiers 37 and 38- to which the electrical signals from Photo multipliers 29 are fed, and the 'voltage difference to the deflection members 16 via the deflection amplifier 33, whereby the 'electron beam is automatically controlled to the Center line of the slit screen as in the thin window arrangement 13 to be scanned exactly. ".

It is to be noted that the thin window image capture according to the invention because of their und.Aufzeichnungsröhre verinfachter construction, its satisfactory S / N ratio, improved resolution and increased percentage of the light used for practical [diagrammatic purposes is advantageous.

■ 009886/1909

Claims (15)

2025674 Pat ent claims [ 1.) Thin window arrangement for recording and recording an optical image, characterized by a transparent thin window (18) which is firmly adhered to .einem transparent part of an evacuated bulb of a cathode ray tube (10) and a target in the form of a slit or slit screen , possesses, furthermore by a light-emitting organ ^ ClS), which on the inner surface of the target is formed and..luminescent when it is from an electron beam (17) is irradiated, continue through light guide f organs (11) which are arranged on the inside of the transparent part and guide the emitted light in a direction perpendicular to the scanning direction of the electron beam, and finally , zustellent by light detectors which are arranged sideways of the transparent portion to the guided light outside the assembly firmly 2. Arrangement according to claim 1, characterized in that a pair of the light guide members (11) and a pair of light detectors are arranged on both sides of the screen. 009385/1969 2025674 3. Arrangement according to claim 1, characterized in that that the thin window (18) and the transparent part of the piston are kept optically isolated from each other. 4. Arrangement according to claim 1, characterized in that that the light guide elements (11) have a light-reflecting surface have a metal screen (24). 5. Arrangement according to claim 4, characterized in that, that part of the reflective surface is slightly beveled so that the; main part of the electron beam passes through the Target is guided, even if it is relatively rough. 6. Arrangement according to claim 4, characterized in that part of the reflective surface is uniplanar or biplanar is beveled. 7. An arrangement according to claim k _t wherein "that a part 'of the reflecting surface is formed parabolic or elliptic, and that the focal point of the parabolic surface is _s that the emitted light can be focused set to when it perpendicular to the scanning of the electron beam (17 ) runs. 8. Arrangement according to claim 2, characterized. that different light detectors have a pair of photoconductive layers j which bear against the outer side surfaces of the piston, whereby 00988S / 1989 ■ '. the guided light is converted into electrical signals. 9. Arrangement according to claim 8, characterized in that the photosensitive layers directly on the piston rest. 10. Arrangement according to claim 8, characterized in that the photoconductive layers over other layers on the piston the latter, together with the photoconductive layers, completely removed from the piston for repair purposes can be. ll.Arrangement according to claim 2, characterized in that j the light detectors a pair of convex lenses (28) and a pair of photo I have multipliers (29) on both sides of the piston. 12. The arrangement according to claim 11, characterized in that the convex lenses (28) are Fresnel lenses, the one have increased focusing effect. 13. Arrangement according to claim 3, characterized by .ein between the thin window (18) and the edge of the foremost Frit glass (30) placed at the end of the piston, the edge previously notched at a suitable angle. 14. Thin window recording and image acquisition 009885/1969 ' tube, characterized by an evacuated flask with .at least
a transparent part, through an electron gun (12) which can emit an electron beam (17), through focus s.ierungsorgane (15) for focusing the electron beam, through deflection.
organs (16) for deflecting the focused electron beam
a thin window arrangement (13) attached to the transparent part
has adhering transparent-thin window (18) and a
Has target in the form of a gap, through a light emitting one
Organ formed on the inner surface of the target 'and
luminesces when irradiated by the electron beam,
by a pair of light-guiding organs (11) which are arranged inside the transparent part and the emitted light in one
Lead direction perpendicular to the scanning direction of the electron beam,
and by a pair of light detectors arranged sideways from the transparent part and the guided light outside j determine this arrangement. : .- f , ι 15. Facsimile machine with a thin-window recording ί and image pickup tube according to claim 14, characterized in that j an electrical arrangement is provided, the reception, balance! and transmission units that -furthermore, the receiving unit! a receiver amplifier (36) for amplifying the received ■ has electrical signals, a detector unit (35) for i Determination of the signals present at this from the receiver amplifier, a video image intensifier (32) for amplifying the detector signals and for applying them to the electron gun (12) and
a deflection amplifier (33) for amplifying the detector signals and
to apply them to the deflection members (16) that the balance unit continues to have a pair of amplifiers (37, 38), each with 009685/1969 a pair of the light detectors is connected to the applied electrical To amplify signals independently of each other, and a comparator unit C39? For comparing the signals thereon from a pair signal voltages applied to the last-mentioned amplifier and for feeding back the voltage difference to the deflection amplifier, that the transmission unit continues to have a transmitter amplifier (HO) for amplifying the signals applied thereto by the comparator unit has »a synchronization unit (42) for generating a synchronized electrical signal, a mixer unit (Hl) for Mixing the electrical signal applied by the transmitter amplifier with the electrical signal applied by the synchronizing unit Signal and a modulator unit (H3) for converting the mixed electrical signal into a transmission wave, and that finally the electron beam for accurate scanning of the Center line of the target of the thin window arrangement is controlled automatically will" · tf9ME / .1 $ e »