Abstract: The technology relates to autonomous vehicles having hitched or towed trailers for transporting cargo and other items between locations. Aspects of the technology provide a smart hitch connection between the fifth-wheel of a tractor unit and the kingpin of a trailer. This avoids requiring a person to make physical pneumatic and electrical connections between the fifth-wheel and kingpin using external hoses and cables. Instead, the necessary connections are made internally, autonomously. For instance, the fifth-wheel may provide air pressure via one or more slots arranged on a connection surface, and the trailer is configured to receive the air pressure through one or more openings on a contact surface of the kingpin. An electrical connection section of the fifth-wheel may also provide electrical signals and/or power to an electrical contact interface of the kingpin. Rotational information about relative alignment of the trailer to the tractor unit may also be provided.

Abstract: A method is provided for detecting a substance, preferably human tissue, in the vicinity of a mobile tool, wherein the substance to be detected has different electrical characteristics from a material that can be processed by the mobile tool. In the method, a change is detected in a capacitance formed by the tool and a counter electrode that is electrically insulated from the tool. A periodic change in the capacitance is detected and the change is produced by the presence of the substance in a region in relation to the tool and by a periodic change in a geometrical characteristic of the tool in this region as the tool moves.

Abstract: An electronic device may have a touch sensitive display that is insensitive to the presence of moisture. An array of pixels in the display may be used to display images. A display cover layer may overlap the array of pixels. A light source may illuminate an external object such as a finger of a user when the object contacts a surface of the display cover layer. This creates scattered light that may be detected by an array of light sensors. The light source may supply light to an edge of the display cover layer at an angle that ensures total internal reflection within the display cover layer is sustained across the display cover layer even when the display cover layer is immersed in water or otherwise exposed to moisture.

Abstract: Switchable antiferromagnetic (AFM) memory devices are provided based on magnetically intercalated transition metal dichalcogenides (TMDs) of the form AxMC2, where A is a magnetic element of stoichiometry x between 0 and 1, M is a transition metal of stoichiometry 1, and C is a chalcogen of stoichiometry 2. Memory storage is achieved by fabricating these materials into crosses of two or more bars and driving DC current pulses along the bars to rotate the AFM order to a fixed angle with respect to the current pulse. Application of current pulses along different bars can switch the AFM order between multiple directions. Standard resistance measurements can detect the orientation of the AFM order as high or low resistance states. The state of the device can be set by the input current pulses, and read-out by the resistance measurement, forming a non-volatile, AFM memory storage bit.

Abstract: There is provided retro-reflective interferometer device for detection and/or measurement of displacements and/or rotations and/or mechanical vibrations, the device includes a transceiver unit including at least one radiation source capable of emitting a radiation beam and at least one radiation receiver; a movable unit movably mounted with respect to said transceiver unit, the movable unit includes one or more movable elements that are susceptible to displacement and/or vibration by an external force; and at least one retro-reflective element capable of reflecting back the radiation beam to form a sequence of radiation patterns; and an analyzing element operationally associated with the radiation receiver for analyzing a displacement change, an intensity change and/or a frequency change in the sequence of radiation patterns. Further provided are systems including the device and methods utilizing the same.

Abstract: A wheel integrity monitoring system for monitoring the integrity of a railcar wheel in an automated manner while the railcar is in operation (i.e., traveling) and comprising a light source that projects light onto the wheel and a light detector that detects the light reflected by the wheel. The wheel integrity monitoring system is configured to analyze the reflected light to determine if the wheel is defective.

Abstract: A touch-screen/gesture based keyboard using gestures on defined zones for providing keyboard input that is simplified to accommodate a small area, doesn't require eye-hand coordination, and can be used with as few as one finger on the same hand holding the device, without looking or employed in Virtual or Augmented applications. The inventive device includes a software application running on a position and movement detection device to provide keyboard operations. The app is a code that runs on a computer device and provides for zones that are monitored for movement, applying that movement to a prescribed chart and delivering the resulting feedback as keystrokes.

Abstract: An apparatus for illuminating objects has an emitting surface and at least two illumination devices. The at least two illumination devices are arranged and designed to generated at least two different illumination distributions on the at least one emitting surface.

Abstract: A thin plate imaging device in accordance with the present invention comprises a guide light plate, at least an imaging unit, at least a photosensitive unit and at least a reflection lens; the guide light plate and the imaging unit are utilized to allow lights to conduct total internal reflection or reflection propagation in one dimension, the photosensitive unit is placed in the path of the total internal reflection or reflection propagation and disposed at the image focus position of the imaging unit; clear images can be obtained without moving the imaging unit or the photosensitive unit back and forth, and objects with different object distances can be imaged on different spots of the photosensitive unit such that relative distances of the objects can be determined by image signals obtained via the photosensitive unit directly.

Abstract: Digitization of film, and more particularly film scanning, includes capturing light transmitted through the film so as to acquire a digitized image. This includes a captured frame comprising a digitized image of at least a portion of at least one image frame of a sequence of image frames, and at least a portion of one or more transport perforations. The method can further include determining an image offset corresponding to at least the captured frame on the basis of a comparison between at least one detected edge in the captured image and a corresponding datum location. A signal representing the image offset can be generated to enable alignment of at least the captured frame.

Abstract: A fingerprint identification device includes a base substrate, a plurality of photosensitive elements and an elastically deformable layer arranged at a first side of the base substrate, and a backlight source arranged at a second side of the base substrate. A light beam from the backlight source is capable of passing through a gap between two adjacent photosensitive elements toward the elastically deformable layer. The elastically deformable layer is nontransparent in the case of not being pressed by a finger, and capable of being deformed in such a manner as to correspond to valleys and ridges of the finger in the case of being pressed by the finger.

Abstract: A thin plate imaging device in accordance with the present invention comprises a guide light plate, at least an imaging unit, and at least a photosensitive unit; the guide light plate and the imaging unit are utilized to allow lights to conduct total internal reflection or reflection propagation in dimension, the photosensitive unit is placed in the path of the total internal reflection or reflection propagation and disposed at the image focus position of the imaging unit; clear images can be obtained without moving the imaging unit or the photosensitive unit back and forth, and objects with different object distances can be imaged on different spots of the photosensitive unit such that relative distances of the objects can be determined by image signals obtained via the photosensitive unit directly.

Abstract: Non-contact strain measurement systems and their method of use to detect strain on rotating components are disclosed. A non-contact strain measurement system comprises magnetic materials plated onto a rotatable component in addition to appropriate encoders and controller. The magnetic materials are spaced apart a first distance D1 when the component is not rotating, and a second distance D2 when the component is rotating. The encoders and controller are utilized to detect strain on the rotating component. A method of using the system to detect strain on a rotating component includes detecting the first distance D1 then detecting the second distance D2, and calculating the strain imparted onto the component from a difference between D1 and D2.

Abstract: Methods and systems for selecting optical modes suitable for defect inspection are disclosed. A method may include: scanning a full-stack wafer of the particular type utilizing a set of optical modes to obtain a set of full-stack wafer images; and de-processing the full-stack wafer to produce a de-processed wafer based on a location of a potential defect of interest indicated by the set of full-stack wafer images to facilitate selection of optical modes suitable for defect inspection of wafers of the particular type.

Abstract: An erosion detector for an exterior aircraft lighting device is configured for detecting the state of erosion of an at least partially transparent cover of an exterior aircraft lighting device and includes: at least one light source, which is configured for radiating light onto the at least partially transparent cover; at least one light detection element, which is configured for detecting light reflected by the at least partially transparent cover and for providing a corresponding detection signal; and an evaluation unit, which is configured for evaluating the detection signal for determining the state of erosion of the at least partially transparent cover.

Abstract: A laser strobe tachometer combines a strobe light with a laser speed sensor. The ability of the laser sensor to accurately determine machine speed enables a synchronous strobe rate to be determined without user intervention. Having locked onto the turning speed, the stroboscope can “freeze” the motion of the shaft, thereby allowing an operator to observe locations, such as on a keyway, flat or screw head, for the optimum placement of the laser spot to generate a once-per-revolution tachometer pulse.

Abstract: There is provided according to some embodiments, a system, device and method for a three dimensional (3D) intraoral scanning of at least a portion of a tooth. An intraoral scanner may include a shadow casting object extending between a light emitter and the portion of the tooth. An imaging module may image the portion of the tooth and/or the projected shadow of the shadow casting object. A method to construct a 3D model may include illuminating at least a portion of the tooth with a light emitter; casting a shadow on the portion of the tooth by an object located between the emitter and the tooth; imaging the portion of the tooth, including at least a part of the shadow; and determining a location of a point on the tooth and related to the shadow, using the image.

Abstract: A display device includes: an optical sensing array to detect light; a backlight to emit light toward a surface of the display device; and a thin optical film layer at the surface of the display device, the thin optical film layer being configured to, while a first shear force is being applied at a first point of contact at the surface of the display device, reflect light having a first wavelength at a front area ahead of the first point of contact in a direction of the first shear force, and reflect light having a second wavelength at a back area behind the first point of contact opposite the front area, the first wavelength being different from the second wavelength.

Abstract: A method for joining a workpiece by means of a welding head, in which at least one line of light is generated on a workpiece, which crosses a joint line at a site to be joined and a joint seam generated at a joined site after processing. The lines of light are imaged at the site to be joined and at the joined site in order to generate reference data relating to the geometry of the site to be joined and measurement data relating to the geometry of the joined sites. The reference data and the measurement data are then compared at one and the same workpiece site before and after processing, in order to determine the geometry of the joint seam independently of the geometry of the site to be joined.

Abstract: A ceiling transport vehicle includes an obstacle detecting portion fixed to a main body portion at a location that is above an article supported by a vertically movable member located at a transport purpose position. The obstacle detection portion is within an area in which the article exists in plan view such that a direction in which detection light, etc., is emitted is tilted outward of the article. When vertically moving the vertically movable member between the transport purpose position and the transfer purpose position, the controller is configured not to determine presence of an obstacle based on detected information from the obstacle detecting portion while the vertically movable member is located in a subject range, and is configured to determine presence of an obstacle while it is not located in the subject range.

Abstract: A flying spot forming apparatus includes a radiation source and a shielding body. A side wall of the shielding body is provided with at least two pairs of helical grooves. Each helical groove is provided with a predetermined slope. A first incident groove is adjacent to a second incident groove. A head end of the first incident groove is higher than a head end of the second incident groove. A tail end of the first incident groove is higher than a tail end of the second incident groove. The tail end of the first incident groove is not higher than the head end of the second incident groove. A first axial cross section of the shielding body intersects with the tail end of the first incident groove. A second axial cross section intersects with the head end of the second incident groove.

Abstract: A light-emitting structure includes a base, a light-emitting assembly arranged on the base, a cover configured to be covered over the light-emitting assembly, and a coupling member configured to couple the cover to the base. The light-emitting assembly emits light onto a workpiece to be inspected by an image inspection device. The light-emitting assembly is circular, and a lens of the image inspection device is rotationally coupled to the base.

Abstract: Provided herein are devices, systems, methods and various means, including those related to printer systems and, more particularly, relate to methods, apparatuses, systems and other means for monitoring a printer ribbon. Some embodiments use a multi-element detector, which is configured to detect a particular type of light emitted from a light emitter. The multi-state detector can include two sensors, one of which includes a polarizer filter that blocks polarized light. Embodiments can be used to determine, among other things, whether or not a printer ribbon is installed in a printer without the use of a snap plate.

Abstract: In one implementation, a method of tracking assets includes obtaining a first image in a first optical domain, where the first optical domain is characterized by a first frequency range. The method also includes detecting a tracking apparatus (e.g., a tag) within the first image in the first optical domain, where a first feature of the tracking apparatus serves as a beacon enabling optical discrimination of the tracking apparatus in the first frequency range. The method further includes determining information associated with the tracking apparatus based on the arrangement of a second feature of the tracking apparatus provided to convey a data set associated with the tracking apparatus.

Abstract: A method for monitoring rotating component includes receiving a continuous waveform sensor signal from a sensor apparatus, retaining the continuous waveform in a memory, and isolating at least one characteristic and/or at least one period of the waveform. The isolated characteristic and/or period is analyzed thereby determining the presence of a waveform anomaly.

Abstract: The present disclosure relates to a method for retrieving medication packages from a pharmacy order-picking device. In modern pharmacy order-picking devices, medication packages are stored for space optimization, which can cause a number of heavy packages to be stored on one shelf, causing the shelf to bend, which may prevent retrieval. In the method according to the disclosure, an operating device (20) is displaced in a displacement position to a predetermined shelf position, at least one medication package (30) on a shelf (11) belonging to the shelf position is moved with a gripping device (22) in the direction of a support (21) and it is then checked whether the at least one medication package (30) has moved fully onto the support (21).

Abstract: The embodiments herein relate to methods and apparatus for detecting whether unwanted metallic deposits are present on a bottom of a substrate holder used in an electroplating apparatus. The presence of such unwanted deposits is harmful to electroplating processes because the deposits scavenge current that is intended to cause electroplating on a substrate. When such current scavenging occurs, the electroplating results on the substrates are poor. For instance, features positioned near the edge of a substrate are likely to plate to an insufficient thickness. Further, where such current scavenging is great, the overall thickness of the material plated on the substrate may be too thin. As such, there is a need to detect when such unwanted deposits are present, such that plating under these poor conditions may be avoided. This detection will help preserve costly wafers.

Abstract: A system for sizing and fitting an individual for apparel, accessories, or prosthetics includes at least one energy emitter configured to emit energy onto a field-of-view that contains an individual, and at least one energy sensor configured to capture reflected energy from within the field-of-view. A spatial measurement module calculates spatial measurements of a surface portion of the body of the individual when the individual is either stationary or moving about in real-time, based on data from the energy sensor.

Abstract: A method is provided for determining the diameter of a rotor of a turbomachine, rotor being equipped with rotor blades. The method involves setting the rotor with the rotor blade ring in rotation, arranging a clearance measuring device assigned to the rotor blade ring outside the region of the latter, measuring the distance to the rotor blades of the rotor blade ring which are rotating past the clearance measuring device, and using the measured distance for determining the diameter of the rotor. During measuring, the rotational speed is identical to, almost identical to or higher than the setpoint rotational speed of the rotor.

Abstract: The present specification discloses a covert mobile inspection vehicle with a backscatter X-ray scanning system that has an X-ray source and detectors for obtaining a radiographic image of an object outside the vehicle. The system is configured to also simultaneously detect passive radiation. The systems preferably include at least one sensor for determining a distance from at least one of the detectors to points on the surface of the object being scanned, a processor for processing the obtained radiographic image by using the determined distance of the object to obtain an atomic number of each material contained in the object, and one or more sensors to obtain surveillance data from a predefined area surrounding the vehicle.

Abstract: An inspecting apparatus includes: a stage including a top surface on which a multilayer structure comprising a first layer and a second layer is placed; a first light irradiation unit which faces a first side surface of the multilayer structure and provides light to a first side surface of the first layer or a first side surface of the second layer; an image capture unit which is on the stage, receives scattered light from the multilayer structure and generates image information of the multilayer structure from the received scattered light, and a control unit which detects foreign body information of the multilayer structure based on the image information of the multilayer structure. The scattered light comprises the light which is provided from the first light irradiation unit and is scattered within the multilayer structure.

Abstract: Systems and methods for processing potentially defective individual packaged modules are presented. A Printed Circuit Board (PCB) that includes a set of individual module substrates can be received and an image of a first side of the PCB can be captured by an image capture module which can include one or more cameras. Based on the captured image, it can be determined whether the set of individual module substrates includes previously identified (e.g., inked) individual module substrates that correspond to potentially defective individual module substrates. In response to determining that the set of individual module substrates includes inked individual module substrates, a map of the inked individual module substrates can be created. Based on the map, locations corresponding to the inked individual module substrates can be marked with a laser on a second side of the PCB.

Abstract: The present invention relates to a method for retrieving medication packages from a pharmacy order-picking device. In the method according to the invention, an operating device is displaced in a displacement position to a predetermined shelf position, at least one medication package on a shelf belonging to the shelf position is moved with a gripping device in the direction of a support and it is then checked whether the at least one medication package has moved fully onto the support. If the check has a negative outcome, an edge of the shelf on which the at least one medication package is stored is detected with a sensor of the operating device and said operating device is displaced to a corresponding shelf position, the gripping device having been brought into the displacement position before displacement.

Abstract: A gesture recognition method comprises capturing images, processing the images to identify at least two clusters of touch points associated with at least two pointers, recognizing a gesture based on motion of the clusters, and updating a display in accordance with the recognized gesture.

Abstract: A vehicular optical touch apparatus includes a screen, an elastic layer, a detection light source, and an image detector. The elastic layer is disposed on the screen and includes a first surface facing away from the screen and a second surface facing the screen. The second surface includes a plurality of inclined surfaces inclined with respect to the first surface. The inclined surfaces totally reflect at least one portion of ambient light entering the elastic layer through the first surface, so that the portion of ambient light leaves the elastic layer through the first surface. The detection light source emits detection light toward the elastic layer. When an object presses the first surface to deform the second surface, the detection light sequentially passes through the elastic layer, is reflected by the object, passes through the elastic layer again, and is transmitted to the image detector.

Abstract: There is provided a tube connector for connecting between a fluid sampling tube and a fluid analyzer, the tube connector includes an end face adapted to identify the tube connector, said end face comprising a reflecting surface having one or more reflective regions adapted to reflect light at a predetermined range of wavelengths.

Abstract: An optoelectronic sensor for recognizing object edges of objects moved relative to the sensor, has a light transmission device with at least one light transmitter, in particular at least two light transmitters, for generating a respective collimated or focused transmitted light beam. The sensor has at least two light receivers for imaging a light spot produced by the respective transmitted light beam on an object, wherein the two light receivers are arranged on two mutually opposite sides of the light transmission device, and has an evaluation unit which is designed to compare the two reception intensities of the two images of the respective light spot taken by the two light receivers with one another and to evaluate the result of the respective comparison to recognize an object edge.

Abstract: An input panel for an interactive input system comprises an optical waveguide; a first radiation source directing radiation into said optical waveguide, said radiation undergoing total internal reflection within said optical waveguide; a diffusion layer adjacent to and on one side of the optical waveguide, totally internally reflected light being frustrated and escaping the optical waveguide in response to pointer contacts on the diffusion layer; a second radiation source directing radiation towards another side of the optical waveguide that is opposite the one side; and at least one imaging device having a field of view looking at the optical waveguide and capturing image frames, wherein said first and second radiation sources are turned on and off in succession and wherein said first radiation source is turned off when said second radiation source is on and wherein said first radiation source is turned on when said second radiation source is off.

Abstract: A sensor apparatus for detecting an overhang on a load of a carrier device, having a sensor arrangement with at least one transmitter and a receiver and also an electronic unit for control purposes. According to the invention, the sensor arrangement senses two regions of the carrier device with a load during a movement of the carrier device such that evaluation of the geometrical position of the regions in relation to one another is made possible, wherein the first region relates to the carrier device and the second region relates to the load. Furthermore, the electronic unit is designed for generating a signal for each region and linking the signals such that it is possible to ascertain an overhang from this.

Abstract: A sensor assembly for electric field sensing is provided. The sensor assembly may include an array of Micro-Electro-Mechanical System (MEMS)-based resonant tunneling devices. A resonant tunneling device may be configured to generate a resonant tunneling signal in response to the electric field. The resonant tunneling device may include at least one electron state definer responsive to changes in at least one respective controllable characteristic of the electron state definer. The changes in the controllable characteristic are configured to affect the tunneling signal. An excitation device may be coupled to the resonant tunneling device to effect at least one of the changes in the controllable characteristic affecting the tunneling signal. A controller may be coupled to the resonant tunneling device and the excitation device to control the changes of the controllable characteristic in accordance with an automated control strategy configured to reduce an effect of noise on a measurement of the electric field.

Abstract: A sensor apparatus for detecting an overhang on a load of a carrier device, having a sensor arrangement with at least one transmitter and a receiver and also an electronic unit for control purposes. According to the invention, the sensor arrangement senses two regions of the carrier device with a load during a movement of the carrier device such that evaluation of the geometrical position of the regions in relation to one another is made possible, wherein the first region relates to the carrier device and the second region relates to the load. Furthermore, the electronic unit is designed for generating a signal for each region and linking the signals such that it is possible to ascertain an overhang from this.

Abstract: An apparatus for dispensing solid articles includes a housing and at least one vacuum source. The housing defines a hopper chamber to hold the articles and a dispensing channel fluidly connected to the hopper chamber. The dispensing channel has an inlet and an outlet defining a dispensing flow path therebetween. The vacuum source is adapted to provide a vacuum pressure and induce a gas flow in the housing. The apparatus is configured to generate a forward drive gas flow from the vacuum pressure and induced gas flow, and the forward drive gas flow conveys articles through the dispensing channel along the dispensing flow path in a direction from the inlet to the outlet to dispense the articles.

Abstract: High-resolution, scalable multi-touch sensing display systems and processes based on frustrated total internal reflection employ an optical waveguide that receives light, such as infrared light, that undergoes total internal reflection and an imaging sensor that detects light that escapes the optical waveguide caused by frustration of the total internal reflection due to contact by a user. The optical waveguide may be fitted with a compliant surface overlay to greatly improve sensing performance, minimize the affect of contaminants on and damage to the contact surface, to generally extend system life and to provide other benefits. The systems and processes provide true multi-touch (multi-input) and high-spatial and temporal resolution capability due to the continuous imaging of the frustrated total internal reflection that escapes the entire optical waveguide.

Abstract: According to embodiments of the present invention, a method for detecting solid articles using an apparatus including a sensor system is provided. The sensor system includes a radiation detector and a radiation emitter configured to direct radiation onto the radiation detector. The radiation detector is operative to generate detector signals proportional to the radiation received thereby. The method includes moving the radiation emitter and/or the radiation detector relative to the other. According to some embodiments, the solid articles are solid pharmaceutical articles.

Abstract: Provided is a device for measuring the quantity of substrates including: a scan unit which generates a signal beam for measuring the quantity of a plurality of laminated substrates from a substrate laminate by scanning the substrate laminate with laser along a lamination direction of the substrates on a side surface of the substrate laminate formed by laminating the plurality of substrates; and a detection unit which detects the quantity of the plurality of laminated substrates by receiving the signal beam. According to the present invention, it is possible to reduce manufacturing costs and improve productivity through simplification of a manufacturing process and reduction of process time by automatically measuring the quantity of the plurality of laminated substrates to improve inefficiency of an existing process of measuring the quantity of substrates through a manual operation.

Abstract: A system for imaging an object comprising a surface for receiving the object to be imaged and an imaging device. The imaging device comprises a housing and a fixed focusing optical device mounted to the housing, whereby the fixed focusing optics comprises a lens for focusing light reflected from the object. A plurality of independent linear imaging sensors are positioned in the housing at different distances from the fixed focusing lens so that a face of each of the plurality of independent linear imaging sensors is aligned parallel to the surface. A processor is coupled to the plurality of independent linear imaging sensors for receiving an output signal from each of the plurality of independent linear imaging sensors representative of the reflected light. The lens defines a plane parallel to the surface, and the plurality of independent linear imaging sensors are adapted to receive reflected light from the object.

Abstract: This invention relates to an optoelectronic sensor for recognizing object edges of objects moved relative to the sensor, having a light transmission device with at least one light transmitter, in particular at least two light transmitters, for generating a respective collimated or focused transmitted light beam, having at least two light receivers for imaging a light spot produced by the respective transmitted light beam on an object, wherein the two light receivers are arranged on two mutually opposite sides of the light transmission device, and having an evaluation unit which is designed to compare the two reception intensities of the two images of the respective light spot taken by the two light receivers with one another and to evaluate the result of the respective comparison to recognize an object edge.

Abstract: An optical measuring apparatus includes a light transmission unit, a light reception unit, a measurement value calculation unit, and a correction unit. The light transmission unit forms a beam of light that focuses in a measurement area where a measurement target object is placed and scans the measurement area with the beam of light. The light reception unit receives the beam of light that has passed through the measurement area and outputs a received-light signal on the basis of the received beam of light. The measurement value calculation unit calculates a measurement value that represents the dimension of the measurement target object on the basis of the received-light signal. The correction unit corrects the measurement value on the basis of the amount of change in the strength of the received-light signal per unit of time of scanning the beam of light.

Abstract: According to embodiments of the present invention, a method for detecting solid articles using an apparatus including a sensor system is provided. The sensor system includes a radiation detector and a radiation emitter configured to direct radiation onto the radiation detector. The radiation detector is operative to generate detector signals proportional to the radiation received thereby. The method includes moving the radiation emitter and/or the radiation detector relative to the other. According to some embodiments, the solid articles are solid pharmaceutical articles.

Abstract: A safety sensing system includes an apparatus for use in a doorway having a powered door slidable for closure of the doorway. The apparatus includes radiation transmitters and/or receivers for providing a curtain of detection beams across the doorway, and is formed as a composite structure that includes: a fixative member connectable by securing means to a side of the doorway at a door frame, the fixative member including a first portion of a mating connection means; and, a housing containing a plurality of the transmitters and/or receivers along its length, and including a second portion of the mating connection means for attaching the sealed housing to the fixative member. The mating connection means allows the housing to be removed and replaced while the fixative member remains in situ.