FR2720211A1 - Device consisting of at least two side-by-side screens, respectively having a distinct display mode and method of implementation. - Google Patents

Abstract

a) Device composed of at least two screens side by side, having respectively a separate display mode and method of implementation. b) Device characterized in that at least one neighboring screen (I) operates in an interlaced mode synchronized with the scanning frequency of the screens of the screen in stereo mode (II).

Description

"Device consisting of two or more screens side by side,

  having respectively a distinct and

  The invention relates to a device consisting of at least two side-by-side screens, each having a distinct display mode and a method of implementing this device. photogrammetric workstations in the form of equipment called digital stereographers, in the process

  to replace the well-known analytical tracers. These pos-

  These workstations usually include at least two screens side by side. A first screen is provided for a mode

  stereo display and another screen is used from the

  classic way. The stereoscopic representation of the couple of aerial shots to be exploited is made on the screen in

Stereo display mode.

  The user observes this screen through a pair of liquid crystal display glasses. The pairs of pictures are displayed alternately with a frequency which must be high enough to avoid flickering. The images are transmitted in turn to

  the right eye, then to the observer's left eye,

  to the viewing glasses, whose glasses stopped

  alternately transmit and transmit the images at the rate of the scan frequency of the frames. The observer has a stereoscopic perception of aerial images. An example

  representative of such equipment is described in the

  applicant's claim W0-92 / 02337 or US patent

4,967,268.

  On the other hand, the neighboring screen is generally used

  graphical interface for the operating program used

  in other words, this screen is used first to

  computer-assisted exploitation of couples of

kets.

  When viewing glasses work

  are in stereo mode and the user is watching

  the screen in stereo mode, it can capture in the peripheral areas

  of its visual field, the screen next door that does not

  not work in stereo mode and this disturbs considerably

  its perception. This results in the scrolling of black bands high half-height of screen, on the conventional screen, in other words on the screen which does not

not work in stereo mode.

  The object of the invention is to create a team

  and a method avoiding such disadvantages when side-by-side use of screens operating with

  different display modes which are particularly suitable for

  for use on a photo workstation.

  grammetric. For this purpose the invention relates to a method of

  type above, characterized in that at least one screen

  sin operates in an interlaced mode synchronized with the

  frequency of scanning screen frames in stereo mode.

  The invention also relates to a device

  for the implementation of the method, this device being

  characterized by a synchronization connection for transmitting a synchronization signal between at least one

  two screens, to operate at least one screen

  sin following an interlaced scanning mode synchronized with

  the frequency of the frames of the stereo screen.

  According to the invention, the operation of the two screens installed side by side, in display mode

  different, is synchronized through a

  synchronization nexion. The implementation of the synchro-

  according to the invention, in more or less complex forms, but which exploit all the

  respective display possibilities of the two screens.

  Advantageously, the two display modes of the screens are mutually adapted so that the screen which does not operate in stereo mode is synchronized to the frame frequency of the stereo screen, according to the well-known mode of scanning two interlaced frames. In this interlaced mode, the entire screen is described by the alternation of two frames, the first constituted by the scanning of the even lines and the second frame constituted

  by scanning odd lines.

  To allow the stereoscopic vision of the whole, the pair of viewing glasses worn by the observer must also be synchronized to the scanning frequency of the frames of the stereo screen and by

  therefore, when it captures the periphery of its

  On the images displayed on the neighboring screen, the observer no longer suffers the disturbance mentioned above, since this screen is also synchronized to the same

frequency.

  Obviously, the process according to the invention can

  be used for a number of screens greater than two,

  side by side and working with modes

different display.

  The invention will be described hereinafter with the aid of a

  process and an installation according to examples of

  shown in the drawings in which:

  FIG. 1 is a diagram of a first example

  FIG. 2 is a diagram of a second exemplary embodiment of the device, FIG. 3 is a diagram of the sequences of synchronized images on the screens operating in different modes of operation. FIG. different displays. Figure 1 shows schematically a first embodiment of the device according to the invention. This arrangement is found for example on a photogrammetric workstation and more specifically on a digital stereo plotter. We can see in Figure 1 the two screens

  installed side by side I, II with different display mode.

  For this we alternately display a pair of aerial photographs alternating at a frequency at least

  sufficient to prevent flickering.

  According to an advantageous embodiment,

  the frequency is greater than 120 Hz.

  The correct attribution of the shots to each eye is ensured by a pair of glasses of visualization

  liquid crystal, that the observer - not shown -

  door on the nose and is synchronized with the scan frequency of the frames. The synchronization of the pair of viewing glasses 1 with the scanning frequency

  frames is ensured by data transmission between

  be a synchronization unit 2 and the pair of viewing glasses 1. The data transmission can be

  realized by a signal transmission line 3, appro-

  as shown in the example, or by a wireless data transmission between the pair of viewing glasses 1 and the synchronization unit 2 using a known type of infrared transmission system. At this

  By way of reference, reference is made to US Pat. No. 4,967,268.

  An appropriate device for the stereoscopic observation of aerial photographs under the

  described form made for example the subject of a description

  in international application WO-92/02337 of the application

  ress. In the direct vicinity of the screen in stereo mode II, there is another screen I. In the example shown, it operates in monoscopic mode and serves as a graphical interface between the user and the operating program.

  photogrammetric. Normally, both screens function

  are completely independent of each other.

  In the example cited, in accordance with

  the invention, via a sync connection

  chronization, we synchronize the two screens I, II by the synchronization unit 2. In addition to the synchronization

  of the pair of viewing glasses 1, the unit of

  chronization 2 synchronizes the two screens I, II, according to

  to the invention. An alternative would be to use a fully separate synchronization unit, which would be exclusively responsible for synchronizing the display modes.

  The synchronization unit 2 provides the

  necessary for synchronization to function

  screen I which does not work in stereo, ie its graphics card, via the connection of

  synchronization, in a synchronous interleaved scanning mode.

  timed at the scan rate of screen frames

stereo II.

  The synchronization connection can be

  in different forms, that is to say a cable of

  signal transmission, wireless transmission, or

  very. The screen that does not work in stereo I, that is to say its graphics card, is then synchronized to the

  frequency of display of aerial photographs. Following the

  yielded an interwoven analysis of images, a first

  layage parses even lines while odd lines are parsed in a second scan. The

  two frames on the non-stereoscopic screen I are thus

  laden with a frequency of recurrence identical to the frequency

  the display of the two stereoscopic frames on

the stereo screen II.

  When the user observes the screen in stereo mode II through the viewing glasses and he sometimes manages to capture the periphery of his visual field, the screen next door that does not work in stereo mode I, he no longer impeded by the appearance, for example, of

  substantially continuous black, thanks to the synchronous operation

  chronized two neighboring screens I, II.

  The synchronization process of the two screens

  according to the invention is quite independent of the frequen-

  these scan selected, that is to say, image frequencies. It allows to synchronize mono screens

  with interlace frequencies of 50 Hz / 60 Hz or

  very, with the display frequencies of the pair of stereoscopic snapshots corresponding, that is to say 100 Hz: 120 Hz / 144 Hz. Moreover, it is possible to work from now on with high resolution screens whose number

  of lines is equal to or greater than 1024.

  FIG. 2 diagrammatically represents another embodiment of the device according to

  the invention implement the method of the invention.

  We find side by side the two screens I, II of Figure 1 operating in different display modes as described above. observation

  screen II which operates in stereo mode is also

  Through a pair of viewing glasses 1 synchronized with the scanning frequency of the two stereoscopic frames by means of the synchronization unit 2 '. In this example, the synchronization signals are transmitted to the pair of viewing glasses 1 by a control system.

  3 'infrared wireless transmission.

  Unlike the first example of

  the synchronization of the two screens I, II side by side

  is done here without a separate synchronization unit. The

  The synchronization signal is received directly at the input of the screen in mono I mode and addressed by a synchronization link to the synchronization input of the other screen II, that is to say to its card. graphic, which works in stereo mode. In this particularly simple example of the device according to the invention, the screen I operating in

  interlaced itself directly provides the signal of syn-

  chronization and, via the connection of

  synchronization, it synchronizes the neighboring screen which

  in stereo mode II. For this purpose, it is sufficient to

  to capture the synchronization signal, preferably the

  General C-Sync, upstream of screen I that does not work in stereo mode and have a sync input

  on the graphics card of the other screen.

  For the rest, the device and the method se-

  this embodiment of the invention have the same

  advantages than the example described above.

  The process according to the invention will be described below.

  again with the help of Figure 3 schematically showing the sequences of synchronized images on

both screens.

  The upper part of Figure 3 shows the

  sequence of images of the screen operating in monos-

  stitch, the axis pointing to the right representing time.

  The even and odd lines of the monoscopic screen are scanned in interlaced mode with a frequency of, for example, 120 Hz. The images of which only the even lines are scanned bearing the letter E in FIG. 3; images scanned exclusively by odd lines are marked with the letter O. Clues assigned to letters

indicate the number of the image.

  The lower part of Figure 3 represents synchronized stereoscopic reconstitution of on-screen images in stereo mode. The couple of shots left L, then

  the couple of right shots R are represented consecutively

  on the screen, with a frequency of 120 Hz.

  indicate the number of the couple of shots.

  As already mentioned, the Hz frequency indicated in FIG. 3 is not to be considered in a restrictive manner, in other words the process according to FIG.

  the invention works similarly with other frequen-

  these, for example with 100 Hz, but also with 144 Hz, or others.

Claims (8)

R E V E N D I C A T I ONS   1) A method of implementing screens having different display modes and installed side by side, at least one of these screens operating in stereo mode with a well-defined frame scan frequency, characterized in that at least one neighboring screen (I) operates in an interlaced mode synchronized with the scanning frequency   screen frames in stereo mode (II).   2) Process according to claim 1, characterized   in that the screen scanning frequency of the screen operating in stereo mode (II) is 120 Hz and the neighbor screen (I) also displays with this frequency the frames interleaved with even lines and odd lines.   3) Process according to claim 1, characterized   rised in that the scanning frequencies of the two screens   neighbors (I, II) are controlled by a synchronization unit. separate sation (2).   4) Process according to claim 1, characterized   in that the synchronization signal for the screen operating in stereo mode (II) is provided by another   screen (I) operating with a different display mode.    Method according to claim 1, characterized in that the observation of the stereo screen (II) is carried out   through a pair of viewing glasses (1) syn-   timed with the scan frequency of the frames.   6) Method according to one of the preceding claims   cedentes, characterized by the use of a workstation   photogrammetric work for the reproduction of photographs aerial, computer assisted.   7) Arrangement for implementing the procedure   consisting of at least two screens installed side by side and having different display modes, at least one of which operates in stereo mode with a frequency defined for frame scanning, characterized by a connection of   synchronization for transmitting a sync signal   chronization between at least two screens (I, II), to operate at least one neighboring screen (I) according to an interlaced scanning mode synchronized with the frame frequency of the stereo screen (II).   8) Equipment according to claim 7, characterized   in that the connection of a synchronization unit   separate arrangement (2) provides the synchronization signals.   9) Equipment according to claim 7, characterized   by the synchronization connection provided between the input of the screen (I) operating in interleaved mode and a synchronization input on the other screen (II) in Stereo display mode.