DE102013221772A1 - Multi-layer display and associated imaging method - Google Patents

Abstract

Multi-layer display with at least three light-transmitting imaging layers, namely a rear layer, a front layer and at least one middle layer, wherein - the rear, the light source facing layer as grayscale display - the middle layer as a color display, and - the front, a viewer facing position is designed as a color display with respect to the middle layer larger gamut.

Description

The invention relates to a multi-layer display, also referred to as multi-layer display, and is basically based on the in WO 2013/045103 described technology for volumetric imaging.

The object of the invention is to further develop this technology to the effect that even with comparatively few image layers and correspondingly low transmission losses, a high-quality 3D representation with true depth effect is realized with image objects extending perpendicular to the image plane in the viewing direction - and not just a quasi 3D-like image impression with objects lying one above the other in the different levels.

In this context, the present text in conjunction with the figures describes a configuration for a multilayer display, also referred to as a multilayer display, which is particularly suitable for realizing a combination of volumetric and autostereoscopic 3D display with flowing boundaries between the two extremes, and which even offers the possibility of representing all variations simultaneously in different places (spatially resolved) - and moreover, in all variants of the autostereoscopic display a quasi arbitrary number (only depending on resolution and control of the second layer) of different perspectives horizontally and vertically.

In addition, of course, normal 2D representation and classic 2 or 3-layer representations are possible even without stereoscopic portion.

• • Layer 1 (hinten) – ist ein pures Graustufen-Display
• • Layer 2 (Mitte) – ist ein Farbdisplay mit reduziertem Gamut – und damit verbesserter Transmissivität
• • Layer 3 (vorne) – ist ein klassisches Farbdisplay mit normalem Gamut

This approach is in principle possible with three identical or even identical (at least partially transparent) displays of different technologies; a clearly preferred for transmission reasons version is schematically in 1 and comprises the following components:

• • Layer 1 (back) - is a pure grayscale display
• • Layer 2 (center) - is a color display with reduced gamut - and thus improved transmissivity
• • Layer 3 (front) - is a classic color display with normal gamut

• a) Nur volumetrische Darstellung im sichtbaren Frequenzbereich zwischen 480 nm und 780 nm. Hierbei wird in jeder einzelnen der vorzugweise drei Bildlagen (das Prinzip ist nicht auf drei Lagen beschränkt und funktioniert entsprechend mit höherer Lagenanzahl) ein eigenständiger, für jede Bildlage einzeln erkennbarer Bildinhalt zugeordnet, der in der Überlagerung aller Bildlagen seine volumetrische Bilddarstellung erreicht, und/oder jede der vorzugweise drei Bildlagen erhält nur eine Teilinformation, die sich erst bei Überlagerung der Bildlagen durch additive und/oder subtraktive Farbmischung und/oder durch tatsächliche und/oder nur durch den menschlichen Wahrnehmungs-Apparat empfundene Interferenzen und /oder Intensitäts- und/oder Farbveränderungen als gesamte volumetrische Darstellung erkennen lässt. Dieses Prinzip lässt sich monochromatisch als auch polychromatisch mit einer Auflösung aller im sichtbaren Farbraum darstellbaren Farben umsetzen. Mittels geeigneter Auswahl der elektrooptischen Licht-Modulatoren und/oder Polarisatoren und/oder Lichtquellen lässt sich dieses Prinzip auch direkt für andere Wellenlängen unterhalb von 480 nm und/oder oberhalb von 780 nm einsetzen.
• b) Nur autostereoskopische Darstellung im sichtbaren Frequenzbereich zwischen 480 nm und 780 nm.

The image structure in such a display can basically take place in three different operating modes:

• a) Only volumetric representation in the visible frequency range between 480 nm and 780 nm. In each case, preferably three image layers (the principle is not limited to three layers and works accordingly with higher number of layers) an independent, individually identifiable image content for each image location assigned , which achieves its volumetric image representation in the overlay of all image layers, and / or each of the preferably three image layers receives only a partial information, which is only superimposed on the image layers by additive and / or subtractive color mixing and / or by actual and / or only by the human perceptual apparatus perceives perceived interference and / or intensity and / or color changes as a whole volumetric representation. This principle can be implemented monochromatically as well as polychromatically with a resolution of all colors that can be displayed in the visible color space. By means of a suitable selection of the electro-optical light modulators and / or polarizers and / or light sources, this principle can also be used directly for other wavelengths below 480 nm and / or above 780 nm.
• b) Only autostereoscopic display in the visible frequency range between 480 nm and 780 nm.

For this purpose, at least in one layer parallax barriers are generated to ensure that each perceived by the right and left eye image portion is different and with a defined crosstalk share (cross-talk) afflicted, and the fields from the right and left eye be perceived belong to a total image impression whose partial images are presented from different perspectives (autostereoscopic representation).

In addition to the prior art, different configurations can be statically and / or dynamically and / or spatially resolved in this approach and / or spatially resolved as desired.

In addition, the typical disadvantage of the autostereoscopic display - namely the reduction of the image resolution - can be avoided since the pixels (pixels and subpixels) of the imaging display layer available for image display are split between the right and left eyes and are further assigned to additional perspectives To equip usable viewing position with at least some spatial freedom.

In the preferred approach described here, the superficial resolution of the imaging electrooptically modulatable layer is not split between the right and left eyes and the parallax barriers are generated in a further electrooptically modulatable layer; in addition, a further electrooptically modulatable layer is additionally inserted between these two layers. their resolution is static and / or dynamically the same or preferably 1.2 to n times larger than that of the first (front) layer. The resolution of the back layer is statically and / or dynamically the same and / or preferably 1.2 to n times smaller than that of the first layer. This is schematically in 2 to recognize.

This approach is preferred because here, main information by means of the front imaging layer and the intensity control of the parallax barriers on the back layer - directly on the light source - and thus the best actual and / or perceived image sharpness can be represented - technically all combinations and / or variations of the individual imaging and image-influencing layers buildable and functional.

Thus, for the preferred approach, each light beam from a specific perspective view passes through three electro-optic modulators whose functions are statically and / or dynamically freely variable and / or whose distance from each other is static and / or dynamic in the z-axis are parallel and / or not parallel to each other and / or whose Ansteuerfrequenzen are statically equal and / or unequal to each other and / or dynamic, any dependencies following, are different from each other.

In this preferred approach, the parallax barriers are not necessarily line-shaped as usual, but in a first example, checkerboard patterns or diagonals. This provides a better spatial representation for the vertical resolution. It should be noted that this embodiment is exemplary only and the design of the parallax barriers static and / or dynamic can be done completely free, according to the assignment resulting from the image task to be displayed and the resulting static and / or dynamic assignments gives the front image-influencing layers.

The interleaving of the two image components in the front imaging plane, which is typical in the prior art, does not take place here, and the halving of the simultaneously displayable different image pixels by the parallax barriers is effected by the intermediate layer with a significantly higher resolution than the barrier pattern Representation of spatially and / or temporally resolved perspectives, clearly overcompensated.

For example, in an arrangement where a main information image pixel on the first layer is assigned a matrix on the interlayer of 10x10 (or with sub-pixel level control, even 30x30 individually controllable subpixels), and at one Parallax barrier matrix of, for example, twice the x and y size of the main image information pixels achieves a resulting overall image detail wealth of up to 225x the resolution of the main information image pixels (with the maximum achievable maximum resolution only at the physically and physically achievable maximum resolution / or resulting resolution of the intermediate layer and for the currently announced ultra-high-definition resolutions can easily assume values well over 1000). That is, for example, with a perspective resolution matrix of 6 positions horizontally and 6 positions vertically per beam (viewing angle ranges for each right or left eye), they still allow the "eye-box" - the spatial area of the from one or more observers can get a spatial image impression - to increase so far that more than 6 people at the same time an independent spatial impression of each full horizontal and vertical perspective resolution while maintaining the original main information image pixel resolution (= static and or dynamic resolution of the first imaging layer).

At the same time, this massive increase in the total image pixels that can be displayed also makes it possible to actively reduce crosstalk between left and right eye information (cross-talk) by, for example, setting the number of displayable perspective resolutions and / or the maximum number of simultaneously visible full independence of viewers so far reduced that you get the opportunity in the rear and / or middle position the respective beam relevant information areas with a contour of one and / or more subpixels and / or pixels with static and / or dynamic, the actual Image content decoupling, to surround electro-optical modulation value. This reduces the available number of displayable image information, for example, in the following ratio: In the example given above, placing an outline consisting of 3 subpixels around the perspective matrix results in a maximum overall image detail wealth of up to 144 times the resolution of the main information pixels , That is, with still full perspective resolution, the ability to simultaneously render this full perspective and image resolution for more than 6 people at a time, but now only for up to 4 people, is reduced. However, the reproducible and / or perceived image sharpness and brilliance increase by more than 55% by reducing the cross-talk.

The control of the cross-talk can be done statically and / or dynamically. In static mode, individual pixels and / or pixel groups are included a fixed intensity value per representable base color (typically R, G, B - but can also use other regimes such as R, G, B, W and / or R, G, B, yellow, etc.) and subpixels driven.

• c) Gleichzeitige volumetrische und autostereoskopische Darstellung im sichtbaren Frequenzbereich zwischen 480 nm und 780 nm, in gradueller Abstufung überlagert und/oder räumlich und/oder zeitlich aufgelöst.

In dynamic operation, the individual pixels and / or pixel groups with a gradually varying intensity value per representable base color (typically R, G, B - but can also be other regimes such as R, G, B, W and / or R, G , B, yellow and / or use any combination of colors resulting from mixing and / or interference from primary colors) and subpixels and / or an intensity value changed in the time pulse-pause ratio per representable base color and subpixel (in the temporal sequence) the respective subpixels at each clock and / or every second and / or every nth and / or a certain rhythm and / or a temporal sequence generated from any dependencies), and / or certain pixels and / or subpixel groups are driven in a fixed and / or dynamically changeable pattern summarized and / or with a gradually changing over time intensity value per representable base color and Mus and / or an intensity value, which can be represented in the time-pulse-pause ratio, per representable base color and pattern (in the temporal sequence, the respective patterns are at each bar and / or every second and / or every nth and / or a certain rhythm and / or a temporal sequence generated from any dependencies).

• c) Simultaneous volumetric and autostereoscopic display in the visible frequency range between 480 nm and 780 nm, superimposed in a gradual graduation and / or spatially and / or temporally resolved.

The two operating modes and examples listed above can be combined as a particularly preferred variant in a wide variety of ways, so that, for example, a permanent 2- or 3-layer representation (in particular according to the existing application WO 2013/045103 ), such as a moving-picture sequence, for example, in the analysis of medical tomography images, with direct activation of the autostereoscopic overlay for certain image shares, for example, deposited patterns to find and / or over several layers (and thus 3D) distributed geometries show takes place. In this case, the relevant area is superimposed autostereoscopically on the volumetric representation - and at the same time for several people viewing without further aids quasi 3-dimensional representation. And depending on the information density of the available image material can also for the detailed 3D analysis in reducing the number of simultaneous viewers to 1 (a single eye-box), the interesting image areas with z. B. more than 200 perspectives views are displayed while all other image areas are still simultaneously for several observers volumetrically and / or volumetrically and autostereoscopically superimposed and / or can only be displayed autostereoscopic. Other applications, for example in the field of computer-assisted simulations and / or computer games, open up this type of dynamically configurable spatial image display incalculable new possibilities and an order of magnitude improved, more natural spatial representation while significantly reduced resource consumption compared to holographic representation.

The overlay is achieved by the fact that the at least three layers are freely controllable for each individual cell - so the information on the first layer can be completed with information from the second and / or the other layers that - depending on the types used imaging layers - this opens up a different characteristic from cell to neighboring cell - and these then give the overlay in the overall image - and / or actually results in a specific characteristic in the form of the direct overlay, in which the representation of individual cell groups and / or the entire layer behind the first imaging layer is calculated so that the data for the volumetric and the autostereoscopic display are combined and, for example, in temporal order and / or calculated form at the same time on this intermediate layer (in three layers - or distributed on layers at more Layers) and combined with a suitable static and / or dynamic design of the parallax barriers in the backmost layer. This results in a harmonious 3D space impression that can be easily processed by the human perception apparatus.

• – Hinterste Schicht (vor der Hauptlichtquelle): Keine Farbdarstellung, sondern nur Schwarz/Weiß und Graustufen – damit ergibt sich eine sehr gute Transmissivität. Als weiteren Freiheitsgrad kann man hier die Auflösung reduzieren, wenn die Bildaufgabe das zulässt, und erhält damit größere einzeln ansteuerbare Zellen – mit weiter verbesserter Transmissivität.
• – Mittlere Schicht: Da hier die Perspektiven-Modulation stattfindet, benötigt man volle Farbdarstellung – bei bevorzugter additiver Farbdarstellung in der Gesamtübertragungsfunktion kann man hier mit einer sogenannten Low-Gamut (also geringere maximal erreichbare Farbsättigung) Version arbeiten und damit die Transmissivität im Vergleich zu einem Standard-Display deutlich erhöhen.
• – Vordere Schicht: Hier wird die Haupt-Bildinformation dargestellt, das heißt hier benötigt man volle Farbdarstellung und High-Gamut (also möglichst gute maximal erreichbare Farbsättigung), und damit resultiert hier die geringste Transmissivität.

Since in all imaging layers all physically existing electro-optically image-forming cells (subpixels) are individually and independently addressable and controllable and the absolute position in the forming x, y, z matrix of a different number (preferably 3) stacked imaging layers and In general, the more cells are available, the more and / or more accurate and / or more complex the total can be in the forming x, y, z matrix For example, the number of layers may exist as a constraint since the transmissivity per layer is not 100%, and thus a significant reduction in overall image brightness takes place. In order to keep this overall image brightness as high as possible, the preferred combination of the individual layers, as already mentioned, is as follows (for operation in combination mode):

• - Backmost layer (in front of the main light source): No color representation, only black and white and grayscale - this results in a very good transmissivity. As a further degree of freedom one can reduce the resolution here, if the image task permits this, and thus obtains larger individually controllable cells - with further improved transmissivity.
• - Middle layer: Since here the perspective modulation takes place, one needs full color representation - with preferential additive color representation in the total transfer function one can work here with a so-called low-Gamut (thus lower maximally achievable color saturation) version and thus the Transmissivität in comparison to a Significantly increase standard display.
• - Front layer: Here, the main image information is displayed, ie here you need full color representation and high-gamut (ie, the best possible maximum achievable color saturation), and thus results in the lowest transmissivity.

With a suitable selection of the currently available and suitable flat displays of various technologies such as LCD, OLED, plasma, EL and / or other flat display technologies, with which it is possible to build electro-optically modulatable cells that have at least a proportion of transparency in these cells, succeeded in achieving a total transmissivity of approx. 1% in a three-layered sample structure. As the flat-panel technologies continue to evolve, this value will continue to improve.

This results in an additional important feature, because it is possible - and sometimes even desired - to use different pixel resolutions per layer and / or even different pixel geometries, however, the electro-optical total transfer function must be based on the respective configuration of the existing x, y, z-matrix can be adjusted. In order to realize the complex overall transfer function, it requires a powerful arithmetic unit (which, however, are quite easily available from the hardware) together with appropriate software that can use such hardware, the required total transfer function also - preferably in real time - calculate and implement.

Depending on the performance of hardware and software, it is also possible to calibrate the resulting multi-layer display by using suitable image pattern representations on the new x, y, z matrix and the comparison of high-resolution images of these image pattern representations corresponding correction factors for each individual cell of the x, y, z matrix calculated and deposited and thus largely tolerances and / or artifacts can be calculated from the resulting representation out.

• a) Durch dunkel (graduelle Graustufen) gesteuerte Bereiche um die eigentlichen Perspektivenzonen für gerade und ungerade Beams (Blickwinkel-Bereiche für jeweils rechtes oder linkes Auge) auf dem hintersten Layer ergibt sich die Möglichkeit, volumetrische und autostereoskopische Darstellung für bestimmte Blickwinkelbereiche zu überlagern (3).
• b) Durch dunkel (graduelle Graustufen) gesteuerte Bereiche um die eigentlichen Perspektivenzonen für gerade und ungerade Beams (Blickwinkel-Bereiche für jeweils rechtes oder linkes Auge) auf dem mittleren Layer lässt sich ein ähnlicher Effekt erreichen, jedoch ergibt sich ein geringerer Auflösungsverlust (4).

In 3 and 4 In summary, two basically different ways of realizing a controlled crosstalk (cross-talk) are illustrated:

• a) By dark (gradual gray scale) controlled areas around the actual perspective zones for even and odd beams (viewing angle areas for each right or left eye) on the backmost layer results in the ability to superimpose volumetric and autostereoscopic view for certain viewing angle areas ( 3 ).
• b) Areas around the actual perspective zones for even and odd beams (viewing angle areas for each right or left eye) on the middle layer controlled by dark (gradual gray scale) can achieve a similar effect, but there is a lower loss of resolution ( 4 ).

The preferred distance between the layers depends on the depth to be achieved in volumetric operation and the pixels or beam origins to be displayed per unit area in autostereoscopic operation (→ number of different perspectives minus the desired number of pixels for controlling the cross-talk). In the examples given here, it is symmetrical 3 mm - but the value can be selected independently for each distance between two imaging layers - depending on the transfer task, the distance between each two adjacent imaging layers is more than 0.2 mm and less than 10 mm - preferably between 1 mm and 5 mm.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2013/045103 [0001, 0019]

Claims (4)

Multi-layer display with at least three illuminated by a light source imaging layers, namely a rear layer, a front layer and at least one middle layer, wherein - The rear, the light source facing layer as a gray scale display - the middle layer as a color display, and - The front, a viewer facing position as a color display with respect to the middle layer larger gamut is trained. A multi-layer display according to claim 1, wherein the size of the individually driven pixels of the middle layer is smaller than the size of the individually driven pixels of the front layer. The multi-layer display according to claim 1 or 2, wherein the size of the individually driven pixels of the back layer is larger than the size of the individually driven pixels of the front layer. A method of operating a multi-layer display according to any one of claims 1 to 3, wherein the backsheet is effective as a parallax barrier with respect to the image content of the front layer, and wherein the central layer is a modulation of the perceivable by a viewer depth content of the overall image is made.

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