Abstract: This sensor, which is connected to an attitude control system comprising a coarse attitude detector on a mobile craft, has an array of photodetectors (1) and a slit (3) interposed between the array and the sun. According to the invention, it comprises a sun sensor having a plurality of parallel slits (3, 4, 5), each slit detecting a sector (C.sub.1, A, C.sub.2) of the overall field of view for a first angular position of the sun to be measured, with a small overlap between adjacent sectors. Said sun sensor further comprises calculation means (31) which receive, on the one hand, information about the insolation of the array and, on the other hand, information originating from the attitude control system (inertial unit 32), in combination with the date, indicating in which sector of the field of view the sun is situated, and which derive from said information the angular position of the sun in said overall field of view.

Abstract: An image detector includes a surface sensitive to photon radiation which is protected from the external environment by a transport window with an internal diopter and an external diopter which is integral with a housing and is placed in front of the sensitive surface. In order to eliminate the phenomenum known as "blooming" due to parasitic reflections causes by intense radiation, the window is formed by a transparent, nondiffusing medium which attenuates photon radiation, with the internal diopter of the window being at a distance from the sensitive surface which is smaller than or at most equal to several times the resolution distance of the detector. Additionally, the external diopter is sufficiently far removed from the sensitive surface such that the first reflection of the radiation coming from a source of maximum radiation will have a level, on the sensitive surface, which is lower than that of the direct radiation coming from a source of minimum radiation which is to be detected.

Abstract: The detector is a charge transfer detection matrix and the measurement is effected by barycentric calculation. The stages of the method are as follows: Centering the measuring field (30) around the estimated position of the bright object (PI(1); selecting a first group of NS brightest pixels (31); selecting from these NS pixels the NA pixels clustered around the pixel having the maximum level (37); finally performing a barycentric calculation on the only clustered NA pixels (IE) of the measuring field.

Abstract: The device includes an objective (12) and a photosensitive detection matrix CCD (110) provided with a read register and an output stage. According to the invention, the device furthermore includes read means (13) for reading the matrix, in groups of 4 or 9 pixels arranged in a square, these groups being arranged in quincunx, and for determining the brightest square group.

Abstract: An arrangement (100) for determining the position of the energy center (o') of the image (S') of a luminous object by barycentric calculation within a window (122) surrounding said image (S') and covering p.sub.l .times.p.sub.c elements of a charge-transfer matrix (120). According to the invention, the arrangement has:a first mode of operation, during which on the one hand said matrix (120) is read by grouping the N.sub.l lines m-by-m (m<p.sub.l) in the output register (121), whereas on the other hand, the output register (121) is emptied by grouping, in the read arrangement (123) of the matrix (120), l (l<p.sub.c) consecutive elements from the output register (121), so as to determine the brightest zone m.times.l (124) of the matrix defining the approximate position of the image (S') on the matrix,a second mode of operation, during which the matrix (120) is first read, by grouping the lines n-by-n (n>p.sub.l), thereafter, line by line in a zone (125) of k lines (k>p.sub.