Abstract: In the field of optic instruments comprising at least one optical architecture, a photoreception assembly and means for acquisition and analysis of the images arising from the said photoreception assembly, the acquisition and analysis means comprising an algorithm of phase diversity type, an optical architecture comprises an optical plate of low or zero optical power arranged in the vicinity of the photoreception assembly and disposed so as to form on all or part of the said assembly a first focused image and a second image defocused by a first predetermined value and shifted by a second predetermined value with respect to the first image. The optic instrument can advantageously be a space telescope.

Abstract: A deployable reflector (RP), for a space observation instrument is disclosed. The deployable reflector has a chosen number of deployable reflecting elements (E1a-E3b) suitable, once deployed in a first position, for together defining a reflecting area in the form of a so-called Reuleaux triangle (RD) with closed convex curve whose width is constant as a function of direction.

Abstract: A device (D) is devoted to supporting a first (M1) and a second (M2) element of a piece of space equipment, such as a telescope for example. This device (D) comprises at least two deployable flexible arms (O11 to O32) each comprising a first end (EX1) and a second end (EX2) which ends are secured respectively to the first (M1) and second (M2) elements and each designed to adopt at least one initial position folded in curves and an unfolded final position, in which positions they hold the first element (M1) away from the second element (M2) by first and second chosen distances respectively, the second distance being greater than the first.

Abstract: A device (D) for compressing digital image data by wavelet transform, the device including a processor (PM) having i) a module (M1) for transforming image data into wavelet coefficients distributed in sub-bands, ii) a module (M2) for estimating for each coefficient, first and second sets of prediction parameters, associated respectively with so-called north-south and west-east directions, based on values of wavelet coefficients of its north or south neighbors, iii) a module (M3) for quantifying the wavelet coefficients, and iv) an entropy coding module (M4) for determining for each coefficient prediction values of expectation and of the width of a Laplace function representing its probability density, based on the first and/or second sets of prediction parameters and on the wavelet coefficient quantified by its north neighbor or its west neighbor, and for entropy coding of the wavelet coefficients quantified via specific associated expectations and widths.

Abstract: A remote sensing instrument using optical aperture synthesis comprises at least two independent remote sensing devices each comprising at least two light collecting means delivering light beams and having a selected field of view and a selected resolution and further comprising recombination means adapted to recombine interferometrically the light beams delivered by said devices so as to deliver a final light beam associated with a resolution better than or equivalent to the lowest resolution of said devices and/or a field of view less than or equal to the largest field of view of said devices.

Abstract: The invention concerns a method of compressing and transmitting digital data, in particular images, at a constant bit rate, the method comprising the following steps:

Abstract: The invention concerns a method for compressing data, in particular images, by transform, in which method this data is projected onto a base of localized orthogonal or biorthogonal functions, such as wavelets.