Abstract: The invention relates to the fabrication of optical microsystems for miniature cameras or miniature matrix displays. It is proposed that N dot matrix arrays and associated circuits should be collectively fabricated, on the front of a semiconductor wafer, to produce N identical chips, with on the side of each array, external connection lands; a plate, used to collectively form N identical optical image-forming structures, each optical image-forming structure covering a respective chip and being designed to form an overall image corresponding with the whole of the matrix array of the respective chip, is fabricated collectively and placed in close contact with the front of the semiconductor wafer; through the thickness of the wafer, conductive vias extending to the contact lands are opened, and, only after these various operations, the wafer is divided into N individual optical microsystems comprising an electronic chip covered by an optical structure.

Abstract: The invention relates to the making of color image sensors for miniature cameras. The method of fabrication includes the formation on the front face of a semi-conductive wafer of a series of active zones comprising image detection circuits, each corresponding to a respective image sensor. Each active zone is surrounded by input/output pads. The wafer is transferred by its front fact against the front face of a supporting substrate. The major part of the thickness of the semiconductor wafer is eliminated, leaving a very fine semi-conductive layer including the image detection circuits on the substrate. This method is characterized in that firstly, layers of color filters are deposited and then etched on the semi-conductive layer thus thinned.

Abstract: The invention relates to method for making a color image sensor. The method comprises: the formation, on the front face of a semiconductive wafer (10), of a series of active zones (ZA) comprising image detection circuits and each corresponding to a respective image sensor, each active zone being surrounded by input/output pads (22), the transfer of the wafer by its front face against the front face of a temporary supporting substrate (20), the elimination of the major part of the thickness of the silicon wafer, leaving a fine silicon layer (30) on the substrate, this fine silicon layer comprising the image detection circuits.

Abstract: The invention relates to wavelength selective optical components for transmitting the light in a narrow spectral band, which is centered around a wavelength, and for reflecting the wavelengths lying outside this band. The component includes an input guide (2) conducting light radiation (3) to a tunable filter (1), an input guide (2) conducting the radiation (3) to the filter (1) in order to perform a first pass through it. The component includes means (6) for returning a first part (4) of the radiation (3) reflected by the filter (1) during the first pass in order to perform a second pass through it.

Abstract: The invention concerns a color image sensor that can be used to make a miniature camera, and a corresponding method for making this sensor. The image sensor comprises a transparent substrate (40) on the upper part of which are superimposed, successively, a mosaic of color filters (18), a very thin silicon layer (30) comprising photosensitive zones, and a stack of conductive layers (14) and insulating layers (16) defining image detection circuits enabling the collection of the electrical charges generated by the illumination of the photosensitive zones through the transparent substrate. The manufacturing method consists in producing the photosensitive circuits on a silicon wafer, transferring said wafer on to a temporary substrate, thinning the wafer down to a thickness of about three to 30 micrometers, depositing color filters on the surface of the remaining silicon layer and transferring the structure to a permanent transparent substrate and eliminating the temporary substrate.

Abstract: An embodiment of the present invention related to fingerprint sensors is described. The sensor comprises an integrated-circuit chip having a sensitive surface, a substrate provided with electrical connections and wire-bonding wires connecting the chip to the electrical connections. The sensor further includes a molded protective resin at least partly covering the substrate and the chip and completely encapsulating the wire-bonding wires. The resin forms, on at least one side of the chip and at most three sides, a bump rising to at least 500 microns above the sensitive surface, this bump encapsulating the wire-bonding wires and constituting a guide for a finger, the fingerprint of which it is desired to detect.

Abstract: A chainable adder receives bits (A, B, C) to give complementary sum outputs (SO, SO*) and carry outputs (CO, CO*). A first stage has differential pairs (P1, P2, P3) receiving bits (A, B, C), respectively, and complements (A*, B*, C*), respectively. The pairs have common output arms and are powered by an identical current (I). First and second output arms include resistors (R1, R2, R3) and (R4, R5, R6), respectively, connected-in-series to a reference potential (M). The resistors define intermediate nodes (A1, A2, A3) in the first arm, (B1, B2, B3) in the second arm. Carry outputs are taken at nodes (A2, B2). A second stage has differential pairs (P4, P5, P6) whose inputs are connected to nodes (A1, B3) for pair (P4), (A2, B2) for pair (P5), and (A3, B1) for pair (P6). Pairs (P4, P6) each have a common arm with the pair (P5) and a non-common arm.

Abstract: In digital signal demodulation and detection circuits, especially digital radio signal reception and processing circuits, the signals are received in analog form and have to be converted into logic levels. This is done in practice by comparing the level of the signal with its mean level. The mean level is established by an RC lowpass filter which introduces an inconvenient delay into the preparation of the mean level. The mean level of the signal, established by an RC filter is compared and applied to an input B of a comparator COMP, at the level of the analog signal delayed by a phase-shifter and applied to another input A of the comparator. In order that the delay introduced by the phase-shifter into the analog signal may be substantially the same as the delay given to the mean value by the RC circuit, the phase-shifter is made with the same RC circuit and an amplifier mounted so as to set up a phase shift transfer function of the (1−RCp)/(1+RCp) type where p is the Laplace variable.

Abstract: A signal aliasing circuit that can be used especially to make a series interpolation cell of an interpolation analog-digital converter comprises two pairs of differential arms powered by one and the same current source connected to a first power supply terminal, each pair comprising two transistors, the transistors of one pair being parallel-connected with the transistors of the other pair. Each group of two parallel-connected transistors is connected by a respective common resistor to a second power supply terminal, the two outputs of the aliasing circuit being the combined collectors of the two groups of parallel-connected transistors. The disclosed device can be applied especially to converters whose architecture comprises what is known as a series interpolation part requiring high precision.

Abstract: A sample-and-hold device comprises a sampling transistor (Qech) and a sampling capacitor (Cech), the sampling transistor being off in hold mode in order to prevent the discharging of the sampling capacitor and conductive in sampling mode to apply a voltage to the capacitor that is substantially equal to the voltage (Vech) at its base.