Vortrag, gehalten am 8.3.2005, University of California, Irvine

Jens Schröter

The volumetric display and the localization of the Other.


Talking about ‘defense’ means talking about space. Defending yourself, your body, your people, your so-called nation or whatever means drawing a distinction, constructing a border which separates you from the – then defined – hostile Other. You may try, perhaps, to make this barrier as impenetrable as possible to prevent every movement across the line. But in reality this strategy might fail. In the moment the border is crossed by the Other you have to defend yourself, for example by trying to destroy the invader with weapons or with pharmaceuticals.
This is even true for the seemingly immaterial realm of cyberspace – as it is revealingly named – in which you have to erect ‘firewalls’ that defend your digital domain against the hacking invader. Although this usage of the term ‘space’ may be somewhat metaphorical, I think it is plausible to state a fundamental connection between defense and space.


So if you want to be successful in defending your proper realm, you need to control space. To control space simply means – of course – to know that space. You need information about where the Other is, how fast he can move through the territory, how fast you can move, whether there are for example natural phenomena such as storms which complicate the situation and so on. That is: you need representations which give you information about the terrain. Traditionally – think of Lessings’ Laokoon images are the type of media which are associated with space. There is – of course – the map as a kind of image/text-hybrid which had an enormous role in the history of the representation of space (Abb. 1, Vermeer) – indeed Farinelli spoke of the ‘cartographical reason’ of modernity. The map is a fascinating topic, which I do not address here and now.
It suffices to say that as the wars became bigger and faster the static map alone wasn’t satisfactory any longer. Gathering information faster and faster became vital. As already noted by Lev Manovich, radar was invented during the Second World War to retrieve real time information about the structure of spaces in which the enemy presumably moves (Abb. 2, Radar): „Detected objects appear as bright spots on the display watched by [a] radar operator. [...] All it sees and all it shows are the positions of objects, 3-D coordinates of points in space, points which correspond to submarines, aircrafts, birds, or missiles.“ The radar screen shows 3D coordinates of points in space – but it often shows them using a two-dimensional screen. This became problematic under specific circumstances, insofar as the spatial structure of the observed territory would be much easier to understand and therefore to control if the spatial relations could be grasped intuitively. So some of the early developments in spatial imagery took place in relation to radar. I’ll return to that later.

But first I’d like to state the problem in somewhat more general terms. I said that images are the preferred medium for representing spatial relations. This is completely obvious when one is concerned with two dimensions. But the representation of the third dimension on the picture plane is traditionally accomplished by techniques of projection of which the most important is of course perspective in painting (Abb. 3 Perspective). Since the 19th century perspective can be automatically rendered by a lens or systems of lenses (as in photography, cinema, video and even in photorealistic computer graphics, where one can find ‘virtual cameras’ with virtual lenses). The perspectival system of representation reigned for centuries and continues until today. But in modernity – the decomposition of perspectival representation in modernist painting set aside – perspective comes more and more into conflict with the needs of modern warfare, modern science and modern medicine. The problem simply is that perspective, although it may not be a conventional, but a mathematically based and in so far objective system of projection, is not isomorphic. That means: You can’t reconstruct the spatial layout of a three-dimensional scene from a two-dimensional perspectival representation of that scene. Many other configurations of objects would fit the same pattern on the image-plane. It’s not difficult to imagine that perspective's non-isomorphism is a big problem for e.g. aerial reconnaissance, the analysis of bubble chamber volumes in particle physics, the visualization of weather phenomena, the correct mapping of the interior of the body in medicine and so forth.
So it comes as no surprise that in modernity different types of post- or trans-perspectival images were developed. These trans-plane images give more and more precise spatial information. One example is – of course – stereoscopy. It was originally invented in 1838 by Charles Wheatstone to prove his arguments about the binocularity of vision and then became, roughly until the 1890s, a popular entertainment medium (Abb. 4 Wheatstone Stereoskop/Nutzung). As Jonathan Crary argues in his influential study Techniques of the Observer, stereoscopy disrupts the perspective paradigm by functionalising the binocularity of the observer, even when the single images are still perspectival. His argument on why stereoscopy disappeared at the end of the 19th century rests exactly on that point. He argues that stereoscopy destabilizes the – so called – ‘paradigm of the camera obscura’, which he sometimes seems to identify with the perspectival order (p. 118), whilst on other occasions he clearly differentiates both fields (p. 34). This destabilization was – so Crary – somewhat too obvious and therefore stereoscopy lost the fight against photography which reconstituted the monocular, disembodied, perspectival gaze.
There are surely many problems in this argumentation but my main point of critique is that stereoscopy simply didn’t disappear at the beginning of the 20th century. Even if it vanished as a popular entertainment medium and left that field to cinema, the post card, the Kodak-self-made-photography and so on, it continued to operate more and more in aerial reconnaissance, especially in the First World War. It is downright impossible to discriminate between a valley and a mountain range on a photo made from a very high altitude – unless you use stereoscopy. It was and is also utilized in photogrammetry or in the analysis of bubble chamber volumes in particle physics and so forth (Abb. 5). It was used in these discursive practices to provide the necessary spatial information. Considering this, the all-to-popular conviction that modernity witnesses an ‘annihilation of space’, as for example Virilio teaches us, has to be differentiated. Of course telecommunications shrank the world, or better: the richer countries, into the the global village. But in other, especially pictorial contexts, space didn't shrink – it literally expanded.


Stereoscopy (here including so-called integral photography or lenticular imagery) is not the only type of trans-plane imagery. There are – I think – two further basic types: One is holography, basically developed around 1948, which as the only lenseless type of image technology in the strict sense, based on an ontology of light as wave, that is: on wave optics, again underscores the break with the perspectival regime of light-as-lines in modernity.
The third type, with which I’m concerned today, is the volumetric display (into which I include so called ‘varifocal mirror’ techniques). Volumetric displays were developed in the 20th century – intimately connected with the topic of defense. Only three years after the Second World War the P.R. Wallis and E. Parker published the paper Three-Dimensional Cathode Ray Tube Displays. The aim is to optimize the already mentioned display of radar signals: „The three-dimensional displays are used to display the positions of the reflected ‘signals’ with respect to the three coordinates of the volume, in order that the radar can be used as an object-detecting and -locating system in three dimensions. [...] The physiological and psychological problems of the human operator peculiar to three-dimensional displays are discussed [...].” They describe different 3D-displays which may be useful to optimize the performance of the human operator and hence the control over space. Parker and Wallis analyze stereoscopic displays as well, but this, as they call it’, „pseudo-3D”, has some limitations. Therefore they propose first steps towards what they name „truly three dimensional displays”. These are the first volumetric displays „in which the echoes appear as bright spots in an actual volume of light.” That’s the central point: Volumetric displays represent the image not on a plane, but in a volume.
In their very early paper Parker and Wallis suggest different types of display for different „aerial scanning patterns” – that is different ways for the radar system to scan the territory in which the enemy is suspected . The aim is to represent the radar-scanning of space in the most direct way. I’ll show you one example (Abb. 6, pattern+apparat) of a so called ‘spiral’ scan pattern and the adequate display arrangement. To the left you see how the radar beam moves through the volume of space, the third dimension is – so to say – into the page. On the right you see the somewhat primitive apparatus, which is used to produce a seemingly three dimensional image representing the scan movements. At that time, only analog computation was available to Parker and Wallis (although digital computers already existed) and so their goal was to map the radar scan directly into the image volume. The Cathode Ray Tubes paint the elevation and the bearing scans on the rotating mirror, where they fuse and represent the radar volume.
Before adressing more advanced volumetric displays, I’d like to turn your attention to a weird coincidence (Abb. 7, Pattern+Rotorelief; 2 Abb). Please compare the spiral scan pattern to the image on the right, which is – as you surely know – one Marcel Duchamps’ Rotoreliefs from 1935 (this one is called Corolle). Rosalind Krauss writes in her book The Optical Unconscious on these discs by dada- and proto-conceptualist-artist Duchamp: „Mounted on a record player's turntable, the disks revolved soundlessly, the product of their turning a series of optical illusions, the most gripping of which was that rotation transformed their two-dimensionality into an illusory volumetric fullness [...].“ Perhaps this is only a superficial coincidence – yet Duchamp was interested in mathematics and you can see the spiral radar scan and his rotorelief as so-called Lissajous-figures... But more important: The similarity may be a symptom for a kind of – via Krauss – optical unconscious generated by or connected with the need to control space in modernity. I think that there is a comparable knowledge implied in both the volumetric radar display and the volumetric art of Duchamp, namely a knowledge about the perceptual production of an image-volume by rotation. It is – this time in a line with Jonathan Crary – a knowledge about specific attributes of human vision. And indeed Duchamp was very interested in the psycho-physiological foundations of vision and in trans-planar images as his experiments with stereoscopy show (Abb. 8). And of course military experiments in the effectiveness of radar operators imply that knowledge too. This is obvious in the development of volumetric display technology.
In the years after 1948 a lot of different volumetric display technologies were proposed. Some of them are still difficult to realize up to now, but some of them became really important. Unfortunately we haven't got the time today to discuss their various archaeologies and effects, especially the basic distinction between solid state- and moving parts-types of display. I'll concentrate on the currently established forms which belong to the moving parts category. In this type of volumetric display the image, or to be precise, the image-volume is based on the rotational movement of a planar or helical mirror screen (Abb. 9) (so in a sense the old paragone of painting and sculpture is resolved in an image-volume, which is produced on a flat screen itself moving in space). An optical or laser beam system synchronized with the movement of the screen writes the image in points or lines or parts (dependent on the design) onto the spinning screen. It is obvious: The knowledge on persistence of vision found in the 19th century does not only lead to the movement- or time-images of cinema, but also to trans-planar space images.
The two most important advantages of volumetric displays are first, that the representation of the spatial object is itself spatial and insofar very intuitively understandable and second that the representation is better suited to collective reception and therefore teamwork. Up to now one central disadvantage is that the images are transparent and so exclude one important clue for the reception of space, that is occlusion (although there is at the moment a lot of research in ‘opacity descriptors’, which admittedly can only be realized in static volumetric displays).
But the advantages seem to prevail – so it’s not surprising that the military already works with such display technologies.
I’d like to show you an unclassified paper from the United States Navy, dated 1994. In this paper a relatively advanced helical volumetric display-technology (Abb. 10) is discussed. Especially interesting is the part of the paper in which potential usages of the display – to be precise: of a future volumetric display – are sketched out. Two examples: First the potentials of the new display technology for Command and Control (C2)-Applications is described (Abb. 11). Men are standing around a volumetric display which presumably shows the intrusion of the enemy or the work of the defending forces (please note the absence of women). Another representation of the potentials of volumetric display technology includes a woman (Abb. 12), but there you have – not surprisingly – the idea of bodily control, of the transparency of the body. Here defense doesn't lie so much in the localization of the outer enemy, but in the control of the female body which is rendered transparent to be controllable – to allow an optimized birth.

There surely is an – if you like – Defense-Unconscious in volumetric display technology. See for example the actual advertisements for the Perspecta 3D-Display, which is currently the best volumetric display commercially available – it renders the image volume in 768 x 768 x 198 Voxels, which is the spatial equivalent of the pixel, in 8 colors at a refresh rate of 24 hz onto a disc rotating with 730 rpm (Abb. 13).
The advertisement is highly symptomatic. In one case the volumetric display is used to present the flight of an airplane over a landscape; and in the other it presents a three-dimensional representation of – HIV. In the first case it might be the defense of the territory against an airplane; in the second it is the defense of bodily integrity against the deadly virus. Again we find the territory and the body as the central sites of defense, which have to mapped and analysed.
I think that in modernity space became an important problem (whilst dissappearing in other fields). In modern warfare space is not any longer an always already fixed territory on which troops meet each other and fight – space itself has to be controlled. Modern medicine – as part of what Foucault called the regime of biopolitics – has not just to observe the symptoms which show up on the surface, but has to map the body in more and more detailed depth to control, optimize and mobilize the wordly flesh. These two types of defense – against the internal and external enemies – result, among other things, in the development of three-dimensional trans-planar images; or at least in certain applications of those image-types.
It’s not surprising that in twentieth-century art one can also find traces of that 3D/efense-unconscious – and in a sense already in Vermeers representation of Map. I already mentioned the weird visual analogies between one of Duchamps’ Rotoreliefs and one specific radar scan pattern.
Now, in my concluding remarks I’d like to direct your attention to Jenny Holzers Installation Sex Murder (Lustmord, 1994). One specific realization of her Installation is especially interesting, becauses there she uses volumetric display technology (Abb. 14) in a highly revealing context, in which one can find again the uncanny connection between the two central topics of defense – control over the territory and control of bodily integrity – and space. First the work is itself an installation which fills space. It maps out a territory which symbolizes in very different ways and in very different materials (Bones, Tables, Media Technologies, Photography and Holzers’ famous neon writings) the Bosnian warzone – and thematizes very decidedly the violating assault on female bodies.
The volumetric display used here resembles a kind of shrine in which texts circulate. Texts, which describe in a poetic and condensed way the horrors when the defense breaks down and the Other – in rape literally – intrudes into the private realm. We can read: “She asks me to sleep in the house but I will not with her body and it’s noises and wetness/She is narrow and flat in the blue sack and I stand when they lift her.” That is: she’s first in the house and then she is flat – this spatial metaphors might be a further hint.
Much more could be said about this complex installation, but I’ll have to stop here.


Today I could only adumbrate that there seems to be an intricate network connecting military and biopolitical defense, strategies for controlling space and the development and application of trans-planar imagery. This network implies special forms of knowledge which circulate through different fields and can also be found in art. There is a lot of research left to be done until this discursive network can be itself mapped out in more detail. Today I just tried to turn your attention to this aspect of the media of defense.

Thank you