Abstract:
An imaging system (50) for providing vehicle security and convenience features that employs face recognition software to identify and track a person. The system (50) employs infrared emitters (30) that emit an infrared signal along a predetermined field-of-view, and an infrared sensor (34), such as a CMOS sensor used as a video signal array, that receives reflected infrared illumination from objects in the field-of-view. A processor (52) including the face recognition software, is employed to detect human faces to identify and track the person. Once a face is detected, it can be compared to a data base to identify the person. Various applications for the imaging system (50) to provide driver convenience and security include determining driver identification as the driver approaches the vehicle, determining if a potential thief is in the vehicle by face recognition, providing driver seat adjustment, rear and side mirror adjustment and steering wheel adjustment, providing vehicle speed control, automatically starting the vehicle, etc.
Abstract:
A vehicle occupant airbag deployment system (50) that detects, identifies and tracks a person (16) in the passenger seat (18) of a vehicle (12), and provides a signal for no fire, soft fire or hard fire of the airbag (20) depending on the location of the person (16) in a crash event. The airbag deployment system (50) employs infrared emitters (30) that emit an infrared signal towards the passenger seat (18) of the vehicle (12) and an infrared detector (34) that receive reflected radiation from objects in the seat (18). Processing circuitry (52), including face recognition software, is employed to detect human face features to provide the necessary detection and tracking of the person (16). In this manner, the system (50) prevents the airbag (20) from firing if the seat (18) is not occupied by a person (16), prevents the airbag (20) from firing if a person (16) is detected, but is too close to the airbag (20), and provides a soft fire if a person (16) is detected, but is within a soft fire range of the airbag (20).
Abstract:
A system for providing recognition of an approaching object located in a distant no-light environment includes an illumination source for transmitting light to the distant object and an imaging device for detecting the light radiation reflected from the distant object to generate an image of the distant object corresponding thereto. The system also includes an independent digital signal processor for calculating a desired optical magnification of a lens of the imaging device as a function of a distance between the imaging device and the distant object and generates a voltage corresponding thereto. The digital signal processor applies the voltage to the digital zoom circuitry of the imaging device to adjust the magnification of the lens so that the image of the distant object is held in a fixed dimension.
Abstract:
An imaging system (50) for providing vehicle safety features that employs face recognition software to identify and track a person. The system (50) employs infrared emitters (30) that emit an infrared signal along a predetermined field-of-view, and an infrared sensor (34), such as a CMOS sensor used as a video signal array, that receives reflected infrared illumination from objects in the field-of-view. A processor (52) including the face recognition software, is employed to detect human faces to identify and track the person. Once a face is detected, it can be compared to a data base to identify the person. Various applications for the imaging system (50) for providing vehicle safety features include identifying the driver or passenger for personalizing the vehicle's airbags, providing pre-crash collision avoidance, providing blind spot detection, providing vehicle crash recording, and providing a warning signal if the driver appears drowsy.
Abstract:
A human presence detection system (50) that employs a frame differencing technique for subtracting out background interference from images generated by the system. The system (50) includes an infrared source (28) that generates a beam of infrared radiation, and an infrared detector (72) that receives infrared radiation reflected from objects in the path of the beam. Face recognition software is employed to determine the presence of a person (16) from the reflected radiation. The infrared source (28) is pulsed on and off and the detector (72) is synchronously shuttered to the pulses so that image frames are generated at different times, where one frame includes reflected radiation and background radiation and another frame includes only background radiation. The frames are subtracted to separate out the background radiation. In one embodiment, the detector (72) includes a pixel array of photodiodes (90) and first and second capacitor storage sites (94, 98) for storing the image frames on a single CMOS chip (70). The storage sites (94, 98) are subtracted in a summation device (102) that is also on the CMOS chip (70). In an alternate embodiment, the frames are stored and subtracted at an off-chip site.
Abstract:
A field-effect transistor in which the gate and source are positioned on opposite faces of a substrate, and a method for its fabrication. In the method, a stop-etch buffer layer and an active semiconductor layer are successively formed by molecular beam epitaxy on a first face of a substrate of semi-insulating material, such as gallium arsenide. A source via hole is etched from the opposite face of the substrate, using a first etchant that does not react with the buffer layer, and extended through the buffer layer with a second etchant that does not react with the active layer. After metalization of the source via hole, electron beam lithography techniques are used to determine its location as viewed from the first face of the substrate. Then a mesa area is formed from the active layer, and drain and gate areas are defined in precise relation to the source via hole, and are metalized.
Abstract:
A method for helping to control a vehicle occupant protection device (22) includes taking an image of the vehicle interior with a digital imager (50) having an array of pixels (53). A contiguous portion of the image less than the entire image is selected. At least one image enhancement technique is applied to the selected image portion. The enhanced image portion is combined with the other portions of the image to make an enhanced image. The enhanced image is analyzed to detect at least one of features and characteristics of the enhanced image. Alternatively, a selected non-contiguous group of the pixels (53) of the imager (50) are read out, as representative of the entire image, to estimate the illumination levels across the entire array of pixels. In one aspect, the imager shutter (56) speed may be controlled to enhance the image.
Abstract:
An RF switch formed as a micro electro-mechanical switch (MEMS) which can be configured in an array forming a micro electro-mechanical switch array (MEMSA). The MEMS is formed on a substrate. A pin, pivotally carried by the substrate defines a pivot point. A rigid beam or transmission line is generally centrally disposed on the pin forming a teeter-totter configuration. The use of a rigid beam and the configuration eliminates the torsional and bending forces of the beam which can reduce reliability. The switch is adapted to be monolithically integrated with other monolithic microwave integrated circuits (MMIC) for example from HBTs and HEMTs, by separating such MMICs from the switch by way of a suitable polymer layer, such as polyimide, enabling the switch to be monolithically integrated with other circuitry. In order to reduce insertion losses, the beam is formed from all metal, which improves the sensitivity of the switch and also allows the switch to be used in RF switching applications. By forming the beam from all metal, the switch will have lower insertion loss than other switches which use SiO2 or mix metal contacts.
Abstract:
A two-gate non-coplanar field-effect transistor and a method for its fabrication. An active semiconductor layer is formed over a stop-etch layer on a substrate of semi-insulating material, such as gallium arsenide, and a via hole is formed from the opposite face of the substrate, through to the stop-etch layer. The via hole is metallized and located from the active-layer side of the device using an electron-beam technique. A two-element gate structure is then formed over the active layer, in approximate alignment with the via hole. Then a source region is ion-implanted into the active layer and into the stop-etch layer, using the positions of the gate elements to self-align the source. Drain contact regions are also formed in the active layer by ion implantation. Contact between the source region and the metallized via hole does not depend on accurate and uniform etching of the via hole. Instead, an opening is etched through the source region to the via hole, and filled with ohmic metal to make good contact with the via hole metallization.
Abstract:
A complementary heterojunction field effect transistor (CHFET) in which the channels for the p-FET device and the n-FET device forming the complementary FET are formed from gallium antimonide (GaSb) or indium antimonide (InSb). An n-type HFET structure is grown, for example, by molecular beam epitaxy (MBE) in order to obtain the highest electron or hole mobility. The complementary p-type HFET is formed by p-type doping of a cap layer thereby eliminating the need for two implants for channel doping. In order to reduce the complexity of the process for making the CHFET, a common gold germanium alloy contact is used for both the p and n-type channel devices, thereby eliminating the need for separate ohmic contacts, resulting in a substantial reduction in the number of mask levels and, thus, complexity in fabricating the device.