Matches 251 - 300 out of 335 < 1 2 3 4 5 6 7 >
Match Document Document Title
4804945 Door alarm with infrared and capacitive sensors  
An alarm system for providing separate discrete signals corresponding with the approach of an individual to a door and the touching of the door knob by the individual utilizes a combination of...
4800368 Pyroelectric detector arrangement  
An arrangement for detecting the passage of living beings into and out of a surveillance region includes optics which concentrate thermal radiation energy from the surveillance region into a...
4799243 Directional people counting arrangement  
An arrangement for detecting the passage of living beings through a surveillance region into and out of a controlled-access space includes at least one pyroelectric detector device that includes...
4797657 Portable self-contained intrusion detector for passenger aircraft  
An intrusion detector for passenger aircraft has a portable housing including on board power means, at least one sensor operable to detect activity along a detection beam alignable to the aircraft...
4772797 Ceiling mounted passive infrared intrusion detector with prismatic window  
A ceiling mounted passive infrared intrusion detector includes a window which has an exterior surface with ridges formed of intersecting planes, which are arranged to provide internal reflection of...
4769545 Motion detector  
A miniature passive infrared motion detector consists of an optical system, a pyroelectric polymer film and an electronic circuit. The optical system is made of a curved Fresnel lens and an...
4768020 Hot body intrusion activated light control unit with daylight photocell deactivation override  
A hot body activates, such as by a person or a car moving into an area scanned through a lens by a passive infrared detector, a light control system having an adjustable length turn on duration for...
4764755 Intruder detection system with false-alarm-minimizing circuitry  
An intruder detection system is provided with circuitry for reducing the risk of false alarms from spurious sources. Such circuitry comprises a pulse generator for producing current pulses of...
4755674 Infrared detector  
An infrared detector has at least one infrared-sensitive detector element and at least one infrared source disposed in a common housing with the detector, with the infrared radiation from the...
4752768 Intruder detector with anti-obscuring means  
An apparatus for detecting intruders comprising a housing provided with at least one window, a passive infrared detector (for detecting the radiation emitted by an intruder around a wavelength λ 1...
4752769 Infrared motion alarm  
The invention is directed to an infrared motion alarm characterized by an infrared detector and an optical arrangement before the detector in the radiation direction for focussing the infrared...
4746910 Passive infrared intrusion detector employing correlation analysis  
For reducing the susceptibility to false alarms and for increasing the detection probability of a passive infrared detector, the actual signals obtained from a first sensor element are continuously...
4745400 Alarm system  
An alarm system comprising a sensor which detects a human body in a fixed detection area and outputs signals, a delay timer circuit which outputs signals after passing a fixed delay time by turning...
4745284 Infrared ray detector  
A pyroelectric infrared ray detector of the so-called dual structure for detecting an intruder or the like through differential output of two pyroelectric infrared ray detecting elements connected...
4743886 Testing apparatus for intrusion detectors  
The monitoring of intrusion detectors is effected by an apparatus for testing the responsiveness to environment-caused, detector-specific useful and spurious signals. This testing apparatus is...
4734574 Light-projecting and-receiving unit for use in a human body detecting apparatus for automatic doors  
A light projecting and receiving unit for use in a human body detecting apparatus having a light projecting section consisting of at least one set of concave mirrors and a plurality of light...
4707604 Ceiling mountable passive infrared intrusion detection system  
The disclosed ceiling mountable passive infrared intrusion detection system includes a field forming mirror assembly and a focusing mirror assembly cooperative to provide a field of view having...
4703171 Lighting control system with infrared occupancy detector  
A lighting control device utilizes an infrared occupancy detector in order to control the lights in a room or area. The occupancy detector monitors changes in infrared energy, which indicate...
4684933 Unauthorized personnel detection system  
A detection system for a doorway discriminates between persons who are authorized to go through the doorway and those who are not. An oscillator with a resonant L-C circuit includes metallic...
4679034 Infrared intrusion sensor with preliminary and primary alarms  
An intrusion alarming apparatus according to this invention detects the human body present in a sensing zone thereof and sends out warning information by means of sound and light. Detection of the...
4663521 Infrared radiation controlled switch with a visible light detector  
An electric switch has an infrared radiation detector and a visible light detector. The switch is activated when both a change in the detected infrared radiation is sensed and the sensed visible...
4650986 Electrical control having automatic mode selection  
A mode control circuit is particularly useful in controlling the operation of an passive infrared appliance switch. When power is first applied to the control, a first output signal is emitted...
4646071 Infrared-ray sensitive alarm device built into electronic equipment  
An alarm device is built into electrical equipment such as a portable radio receiver or tape recorder and connected to a loud speaker unit for producing an alarm sound by sensing infrared rays...
4644147 Method for deflection of optical rays and an optical arrangement therefor  
A method and apparatus is shown for receiving optical rays with a maximum angle of sensitivity so that a single detector can monitor a wide, spherical angle. This method is used with infrared...
4641134 Infrared-sensitive detector consisting of Peltier element  
The invention is concerned with a device for the detection of moving objects which are warmer or cooler than a static environment. The device consists of a detector unit (1) connected to a...
4621258 Proximity detecting apparatus  
Apparatus and method for detecting changes in capacitance of an antenna due to intrusion into the antenna field by a body of different dielectric constant, in the presence of induced AC voltages on...
4618854 Double eye type crime preventing sensor system  
A double eye type crime preventing sensor system comprising a pair of detection axes (6) substantially horizontally spaced apart and extending in substantially the same direction in a predetermined...
4618770 Electrical controller having a window discriminator  
An electrical control has a detector which senses the infrared radiation within a given area. A pair of comparators function as a window discriminator. A voltage divider provides reference bias...
4612442 Passive infrared intrusion detection system  
A passive infrared intrusion detector has: a multi-faceted parabolic reflector for dividing a target controlled area into a plurality of optically divided detection zones, for collecting...
4590460 Stairwell security system  
A security system includes an entry monitoring sensor for detecting movement into a first space, a first area monitoring sensor for detecting occupancy in the first space, at least one area...
4570157 Infrared intrusion alarm system capable of preventing false signals  
An alarm device responsive to entering or trespassing comprising: (a) a sensor circuit, including an infrared ray sensor, producing an output having positive and negative peaks based on outputs...
4551711 Infrared-type intrusion detector  
An infrared-type intrusion detector for monitoring the presence of a person is disclosed. The detector has a plurality of concave reflector segments for defining separate fields of view. Infrared...
4529874 Motion detector for space surveillance  
A motion detector responsive to infrared radiation, e.g. for use in burglar-alarm installations, comprises a pair of juxtaposed sensors monitoring adjacent fields of view of a space to be surveyed,...
4523095 Radiation detector with asymmetrical pattern  
A radiation detector having a plurality of discrete fields of view with respect to a plurality of sensing elements. The sensing elements are connected such that their output signals are summed to...
4510488 Passive infrared intrusion detector  
A passive infrared intrusion detector is configured to resemble an electrical wall outlet. The unit includes a light for visually indicating the direction of its beam of sensitivity, and a lens...
4468658 Simplified intruder detection module  
An Improved Intruder Detection Module is disclosed that incorporates a compact, unique optical system, a detector array, and an electronic system of a combined size and configuration that permits...
4447726 Passive infrared intrusion detector  
A passive infrared intrusion detector is provided of the type having an infrared sensor for detecting a change in temperature in the field of view of the sensor caused by an intruder moving...
4442359 Multiple field-of-view optical system  
Disclosed herein is a multiple field-of-view optical system which is adapted for use in electromagnetic radiation-responsive systems, e.g. in passive infrared intruder detection systems. The...
4401977 Radio transmitter for repeated bursts of oscillations  
This radio transmitter is for use in an access control system and comprises a hands-free pocket token arranged to transmit bursts of oscillations at a preset carrier frequency with a preset number...
4375034 Passive infrared intrusion detection system  
A passive infrared intrusion detection system having a mirror assembly providing a protective curtain which is relatively narrow in the horizontal plane and which substantially encompasses the...
4345167 Capacitance proximity sensor  
A method for detecting the change in the capacitance of an antenna caused by the approach of a person to the antenna, including the step of charging said antenna to a predetermined voltage relative...
4342987 Intruder detection system  
The improved intruder detection system of the present invention, because of its sensor, optical, and electronic systems, is uniquely capable of responding only to radiation from an intruder to...
4339748 Multiple range passive infrared detection system  
A passive infrared detection system which exhibits a consistent optical aperture and sensitivity over different operating ranges. The system includes a mirror assembly having a plurality of...
4321594 Passive infrared detector  
A passive infrared intrusion detection system is provided in which one or more Fresnel lenses are employed to focus received infrared energy onto a detector element which provides an electrical...
4318089 Infrared detector system  
An improved infrared detector system includes a pair of thin film thermopile sensing elements that receives reflected energy from aspheric reflectors that are designed to provide optimum energy...
4317992 Object detecting apparatus  
A passive and low cost object detector utilizing a focus module used in auto focus cameras to determine the presence of objects within the field of view of the module.
4307388 Arrangement in order to prevent false alarms of a passive infrared motion alarm  
In an infrared motion alarm an optical filter arranged in front of an input of an infrared detector is attached to a heat sink in the form of a solid metal crucible in order to reduce the...
4263585 Intrusion detection system with a segmented radiation sensing mirror  
An intrusion detection system has an optical device for focusing radiation energy onto radiation sensing elements. Connected to the sensing elements is a circuit which produces intrusion signals...
4242669 Passive infrared intruder detection system  
Radiation detection apparatus is disclosed including a first detector (6) for detecting radiation at a wavelength which is preferably in the infra-red region, and a device for sensing the presence...
4209783 Object identification system  
A transmitting/receiving antenna radiates a sweep frequency signal as an interrogation signal to an answer device. The answer device includes a plurality of resonators which are connected in...
Matches 251 - 300 out of 335 < 1 2 3 4 5 6 7 >