Other

Societe Fontaine

Commissariat a L'energie Atomique

Biospace Instruments

Claude Hennion

Jacques Lewiner

Serge Maitrejean

Didier Perino

Eugeniusz Smycz

Didier Leonard

Pascal DeSaute

Jean-Louis Gerstenmayer

Irène Dorion

Gilbert Berthier

Bernhard Sandkamp

Two-dimensional detector of ionizing radiation and process for manufacturing this detector This detector comprises sheets () emitting particles by interaction with ionizing radiation, semiconducting layers () that alternate with the sheets and can be ionized by the particles, and groups of conducting tracks () in contact with the layers. Means () of creating an electric field are used to collect charge carriers generated in the layers due to interaction with particles, through the tracks. For example, the layer and the corresponding tracks are formed on each sheet and the sheets are then assembled together. For example, the invention is applicable to radiography and can achieve good X-ray detection efficiency and high spatial resolution at the same time.

Two-dimensional detector of ionizing radiation and method for making same

This is a method of generating a plurality of images of a substrate from radioactive radiation coming from a plurality of radioactive tracers contained in the substrate. To this end, data representing the different detection signals generated by a detector are memorised, individually for each radioactive emission detected during a certain observation period, then statistical processing of these data is carried out in such a way as to estimate the images of the different tracers which correspond best to the set of memorised data.

Method of processing autoradiography image

A device is provided for grounding a metal vehicle body or the like, comprising an arrangement for automatically creating at desired times, between the body (1) and the ground (3), ions which, under the effect of the electric field which may exist between the body and the ground, are driven towards the body or towards the ground depending on their polarity and thus equalize the potentials of the body and the ground.

Devices for grounding vehicle bodies or similar

The invention relates to an electronic circuit for remote interrogation of a receiver through a two wire line and to detect the response signals emitted by this receiver. The circuit comprises means for comparing with a reference voltage the actual voltage defining said response signals. This reference voltage is a weighted variable voltage obtained by low band-pass filtering, in a resistance-capacity circuit, of said actual voltage.

Electronic interrogation circuits

An installation for controlling and monitoring the different coded locks of an assembly embodying: An issuer for elaborating coded keys for controlling said locks and a reader associated with each lock, adapted for unlocking this lock on simple presentation thereto of a correctly coded key, this issuer and this reader being adapted so that detection by said reader of the code y recorded by said issuer on each new key of order p assigned to the lock associated with this reader results in the invalidation of the code x recorded on the key of order p-1 previously assigned to this lock, each code y being derived from code x by an algorithm y=f(x) stored at least in the issuer. At any time the reader is responsive simultaneously to a number m greater than 2 of a non invalidated codes of the succession x, f(x), f.sup.2 (x) . . . f.sup.n (x) and is adapted so that by reading any one of these codes it automatically invalidates all the lower rank codes of the succession considered.

Installation for controlling and monitoring the different coded locks of

A reader identifies coded electronic badges without contact with the latter, by simple inductive coupling of inductances, the electrical supply of the badge being ensured from a voltage at high frequency F generated by the reader. The code of the badge, composed of a sequence of bits following one another at a frequency f very much less than F, is used to modulate a voltage of intermediate frequency fi comprised between f and F and the thus modulated voltage controls an electronic switch adapted to short-circuit a resonant circuit of the badge.

Device for identification by proximity

In a coded locking device, unlocking of which is controlled by composing any one of two separate codes, namely a code in use known by entitled users and a responsible person or 'first code x' and a secret code or 'second code y', able to be derived from the first code x by a particular law known only to the responsible person, the first composition of the second code y automatically ensures unlocking of the device and, in a way sufficiently postponed for the users to become acquainted with it, the three following operations: invalidation of the first code x, adoption by the device of the second code y as new first code, sensitization of the device to a third code z derived from the preceding second code y by the above low, this third code z serving as the new second code.

Coded locking device, more especially with keyboard

The invention relates to electronic badges equipping portable objects, such as plastified cards and capable of being identified at a distance by suitable readers in order to ensure operation such as the unlocking of a lock. These badges are of a passive type, that is to say supplied exclusively from the outside by inductive coupling and they are in addition of a type reprogrammable through channels, each comprising an inductive coupling (at the level of inductances) from a suitable apparatus. The circuitry for forming the binary coded identification signals of the badge comprise a dead memory, a life memory or buffer and a rapid reading and writing circuit which provides the connections between these two memories, as well as the connections between the dead memories and the reprogramming channels.

Coded objects identifiable by proximity and devices for changing the

The invention relates to devices for controlling accesses of the security chamber type which comprise at least two doors (2, 3). A single program selector (14, 15) with easy and instant control allows the security chamber operating program to be chosen at will from several predetermined programs.

Device for controlling accesses of the security chamber

An electronic assembly is provided associated with a capacitive keyboard for identifying the depressed keys of this keyboard, which keys are disposed at the intersection points of a checkerboard pattern formed of m lines and n columns, comprising means for successively applying to the inputs of the m lines trains of n successive identical pulses, means for successively collecting at the outputs of the n columns the signals created by these pulses and means for detecting and identifying, among the signals collected, the echoes which exceed a predetermined threshold and which correspond to depressed keys, which means comprise a comparator for comparing the amplitude of said signals with that of a reference voltage. At all times, the comparison reference is related to the average in time of the mean of the amplitudes of the signals received at least two of the column outputs.

Electronic identification assemblies of capacitive keyboards

To provide a remote control by means of coded signals, a portable transmitter case (3) is used comprising, on the one hand, a keyboard (5) with keys (6) for directly forming the coded signal on said case and, on the other hand, means for recording this coded signal, for storing it in the memory for a time t.sub.o at the end of which it is automatically erased, as well as a control button (10) ensuring the instantaneous transmission of the signal thus previously stored in the memory.

Remote control coded devices

For reading a coded sequence of magnetic signals recorded on a card, which sequence is formed of bits of identical duration the reading of which results, for the 0s, in a single change of level of an electric voltage, and for the 1s, in two such changes evenly spaced apart in time, the real duration of each bit read is measured, and the time of identification of each bit is adjusted depending on the real duration t.sub.0 of the preceding bit and on the nature of this preceding bit by giving to the time interval T which separates the end of reading of this preceding bit and the time of identifying the following bit, if the preceding bit is a 1, a value T.sub.1 equal to 5/8 of t.sub.0 or to 11/16 of t.sub.0 and if the preceding bit is a 0, a value t.sub.0 equal to 7/8 of t.sub.0, or else equal to 13/16 of t.sub.0 if the bit preceding the above 0 was again a 0 and to 15/16 of t.sub.0 in the opposite case.

Processes and devices for reading magnetic access control cards or

A portable case (2) is provided for emitting, in response to pressure on a push button (1), a control signal (S) coded in accordance with a code recorded in said case. Timing means (8) are provided for automatically neutralizing the code when a predetermined time has elapsed from a predetermined moment, which then makes the case inoperative.

Portable control code transmitter with delayed code neutralization

The invention relates to an electroacoustic piezoelectric transducer comprising a mechanically stretched vibrating membrane composed of a polymer sheet (10) jointly interposed between two metallic electrodes (9 and 11), one of them (11) being constituted by metallization of one of the faces of the polymer sheet (10). The other electrode (9) is constituted by an autonomous metallic sheet offering a high resistance to mechanical tension, adhering intimately against the other face of the polymer sheet.

Electroacoustic piezoelectric transducers

The invention provides a device for measuring ionizing radiations, comprising a Geiger-Muller tube (1) whose high supply voltage is obtained from pulses which are emitted (by 6,7) at a constant relatively low frequency as long as a predetermined threshold is not exceeded by the intensity of the radiation and (by 6,7,4 and 32) at an increasing frequency depending on the output of the tube, after said threshold has been exceeded. Thus, alarm dosimeters having very long independent operation may be formed.

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Paris, France

Claude Hennion