DE1807950U - ARRANGEMENT FOR THE ELIMINATION OF THE LINE STRUCTURE IN TELEVISION TUBES. - Google Patents

Description

RA. 765220 * 21151 DIPL. ING. HANS WESTPHAL

PATENT ADVOCATE

VILLINGEN / SCHW .. on December 17th, 1959

SEB. KNEIPPSTR. 14 - TEL. 2194

S A B A - Black Forest apparatus construction institute August Schwer Sons G.m.b.H. Yillingen - Black Forest

Arrangement for eliminating the line structure at

TV picture tubes »

The line structure is often disturbing in the television picture in appearance, especially when the viewer is sitting fairly close to the screen. The viewer is namely Experience has shown that he tries to enlarge his viewing angle to the screen as much as possible, since it is too small Viewing angle puts too much strain on the eyes. For this reason, today with the Televisions use the 53cm picture tubes compared to the 43cm tubes always more preferred * The larger the viewing angle for the viewer, the clearer they are Line structure and the so-called staircase effect visible, which occurs when oblique lines are transmitted.

To determine means for achieving optimal, vertical resolution have been around for some time, in particular von Schröter, Wheeler, Laughren, numerous investigations have been carried out. The results of this Investigations which essentially focus on the generation of a special shape of the light spot on the screen

Bank account; German Βλνκ Viuincen No. 21449 - Postal check: Karlsruhe No. 41702

can be summarized as follows according to Schröter:

The annoying line structure and the staircase effect are without loss of resolution in the horizontal then no longer visible when the electron beam on the screen The lighting effect created the shape of a standing rectangle

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"possesses at cos. -shaped distribution of brightness, such _y that adjacent rows overlap. This condition by a. electron beam with a rectangular cross-section to meet, is not in the current state of the electron optics at the wide angle tubes (110 °) is possible. The only realization of the The above-mentioned conditions have so far been achieved with high-quality control receivers in studios by means of the so-called line wobble with a very high frequency (20MHz). However, this method is very complex and also not always fully satisfactory

The! Inflation aims to be one compared to the known electrical arrangements simple, cheap and reliable arrangement for eliminating the line structure to create »She recognized that one can achieve the desired goal · with optical means without any intervention takes place in the circuit of the television set Arrangement can therefore be made afterwards on each. Attach TV set »

The arrangement according to the innovation to eliminate the line structure and the staircase effect in the television picture is that in a certain relatively small distance

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in front of the luminescent layer of the screen one made of transparent Material existing optical aperture is arranged such a structure or surface texture that it The light emitted by the screen scatters across the line direction in such a way that the viewer can see the cover adjacent image lines in the gaps

In part, it is made of transparent material optical diaphragm provided on at least one of its surfaces with parallel grooves in the line direction, the mutual The distance between these grooves is smaller than the distance between adjacent image lines - is .. In further development of the Innovation, the grooves of the optical diaphragm have such a shape and depth that the dispersion width transversely to The direction of the grooves is the same as the line spacing. Appropriately form the adjacent grooves in the Cross-section a wavy profile.

In order to avoid loss of light, the optical screen, which has the same refractive index as the screen glass, is adapted in their shape to the curvature of the screen, preferably in such a way that it rests directly on the screen »

To avoid air pockets between the television screen and the optical cover, these can be fixed with adhesive, Ganada balm, for example, whose refractive index matches that of the screen glass. To simplify the structure, the optical screen can also be used as a protective screen for the picture tube

to serve. It can be provided with contrast-enhancing color additives. Finally it is also possible to use the outer appropriately designed surface of the screen by. TV tubes themselves can be used as optical screens *

The effect of the optical aperture according to the innovation can be seen on the television set, for example, by placing a a few millimeters thick, made of transparent material with a. Refractive index n> 1 existing plate brings whose surface at least on one side with parallel Grooves each about 0.1 mm in diameter and about 0.1 mm mutual spacing is provided. If you hold this plate so immediately in front of the screen that their grooves run in the direction of the picture lines, then that is from the television screen light passing through the plate is scattered vertically in such a way that the line structure and the The staircase effect for the audience disappears. There is no loss of image resolution in the horizontal plane, the sharpness of the pixels in the line direction is therefore not impaired *

It goes without saying that it is with the means in accordance with the innovation possible to achieve a scattering effect also in the horizontal, if for example the individual pixels should appear a little more covered in the horizontal to the human eye. To do this, the grooves need to be of the optical diaphragm run vertically, the one desired here versus that of the line structure

less scattering effect can be achieved, for example, by means of a correspondingly smaller groove depth in the panel » In other words, an optical shutter to eliminate the line structure and at the same time provide greater coverage the image points should have a groove pattern with stronger parallel grooves in the horizontal and weaker ones Carry parallel grooves in the vertical, so that the G-anze looks and acts like a latticework. Of course Care must be taken that the diverging edges of the diaphragm are sufficiently small compared to the Line spacing are so that no interference phenomena occur »

The following is an example of inflation based on the Drawing described and explained in more detail. In this show

Fig. 1 shows a picture tube in section and

Pig, 2 a greatly enlarged partial section with graphic Representations of the brightness distribution »

The picture tube 1, which is customary in television receivers, is known to have a luminous layer on the inside of the screen 2 3, the gate of the picture tube 1 is usually also a protective screen 4 · According to the hiring is immediately in front of it an optical screen 5 is attached to the screen 2. As in Fig. 2 is shown in more detail, the attached to the screen 2 optical shutter 5 has a certain, relatively small distance from the luminous layer 5, in the exemplary embodiment is to avoid air inclusions

Aperture 5 on screen 2 with a clear one Glued on cement 6, which has the same refractive index as glass.

The aperture 5 is also made of a transparent material with the to avoid reflections. same refractive index as glass. She is on hers Provide the outer surface with small grooves perpendicular to the plane of the drawing, which appear as a wavy line in the section. 7 are visible.

Now, the luminescent layer in line shape scanned by the electron beam of the picture tube, as in FIG · 2 greatly enlarged ^f each written lines and row spaces of the light-emitting layer 3 as hell.e rectangles 8, 8 '', 8 * * * (vertical section by the light-controlled line) and dark rectangles 9 ', 9 ^lf , 9 ^ttf (line space not scanned by the electron beam). If the brightness values of the luminous rectangles 8 ·, 8 ^tl; , 8 ^tt! and the non-luminous rectangles 9 ', 9 ¹ ', 9 ' ^tr , a rectangular curve 11 with the rectangles 11', 11 ", 11 ' ^rt , which corresponds to the luminous rectangles 8', 8 ^{! f} , 8 »' ^r correspond. These; The illustration therefore shows the brightness distribution on the luminous area perpendicular to the luminous area and perpendicular to the direction of the line *

The influence of the optical diaphragm 5 according to the innovation is shown in the diagram with the axis 12. The brightness of the luminous rectangles 8 ^f , 8 '", 8 ·" is

len 7 distributed on the surface of the diaphragm 5 in the form of curves 13 ', 13 ", 13 *' *. The overall impression of the brightness resulting from these curves therefore leaves the dark rectangles 9 '? In between for the human eye. 9 ^tf , 9 * * * no longer recognize. You only need to add up the overlapping curves 13 ', 13'S, 13' ^M and then you get a line of approximately constant brightness indicated by the dashed line 14 over the entire section shown *

Claims (1)

SABA P.Ä. 765 220 * 21.1259 17.12.1959 ύ S c h u t ζ a η s ρ r ü c h e 1 ♦ Arrangement for eliminating the line structure (Line space) in television picture tubes, characterized in that in a certain, relatively low Distance in front of the luminescent layer of the screen, an optical screen made of transparent material Structure or surface texture is arranged that it transversely the light emitted by the screen to the line direction in such a way that the adjacent image lines are in the spaces for the viewer cover, 2 »Arrangement according to claim 1, characterized in that that the optical diaphragm made of transparent material is parallel on at least one surface Has grooves in the line direction, the mutual spacing of which is smaller than the spacing of adjacent image lines is. 3 · Arrangement according to claim 2, characterized in, that the grooves of the optical shutter have such a shape, and Have a depth that the spread across the direction of the grooves is the same size as the line spacing » 4. Arrangement according to claim 3, characterized in that that the grooves lying next to each other form wavy lines in the cross-section * 5 * arrangement according to claims 2 to 4 _? characterized in that the optical diaphragm has the same light refractive index as the screen glass "has, its shape is adapted to the curvature of the screen and preferably rests directly on the screen. 6. Arrangement according to claims 2 to 5, characterized in that characterized in that to avoid air pockets, the screen and the screen by adhesive, for example Ganada balm, which have a refractive index that corresponds to that of the screen glass, 7. Arrangement according to claim 6, characterized in that that the optical aperture also serves as a protective screen for the picture tube and with contrast-enhancing Color additives is provided » 8. Arrangement according to claims 2 and 3 _? characterized in that the outer, correspondingly designed surface of the screen itself forms the optical shutter.