EP0319876A2 - Motion alarm with an infrared detector - Google Patents

Motion alarm with an infrared detector Download PDF

Info

Publication number
EP0319876A2
EP0319876A2 EP88120222A EP88120222A EP0319876A2 EP 0319876 A2 EP0319876 A2 EP 0319876A2 EP 88120222 A EP88120222 A EP 88120222A EP 88120222 A EP88120222 A EP 88120222A EP 0319876 A2 EP0319876 A2 EP 0319876A2
Authority
EP
European Patent Office
Prior art keywords
sensor
collecting optics
radiation
motion detector
optics
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP88120222A
Other languages
German (de)
French (fr)
Other versions
EP0319876A3 (en
Inventor
Berthold Geck
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ABB AG Germany
ABB AB
Original Assignee
Asea Brown Boveri AG Germany
Asea Brown Boveri AB
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Asea Brown Boveri AG Germany, Asea Brown Boveri AB filed Critical Asea Brown Boveri AG Germany
Publication of EP0319876A2 publication Critical patent/EP0319876A2/en
Publication of EP0319876A3 publication Critical patent/EP0319876A3/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G08—SIGNALLING
    • G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B13/00—Burglar, theft or intruder alarms
    • G08B13/18—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength
    • G08B13/189—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems
    • G08B13/19—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using infrared-radiation detection systems
    • G08B13/193—Actuation by interference with heat, light, or radiation of shorter wavelength; Actuation by intruding sources of heat, light, or radiation of shorter wavelength using passive radiation detection systems using infrared-radiation detection systems using focusing means
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S250/00—Radiant energy
    • Y10S250/01—Passive intrusion detectors

Definitions

  • the invention relates to a motion detector of the type mentioned in the preamble of claim 1.
  • Motion detectors with infrared detectors are becoming increasingly popular for room surveillance both inside and outside buildings. As passive detectors, they respond directly to radiation objects that emit thermal radiation. Such a radiation object is also a person, for example, who penetrates into a room to be monitored. There is therefore no need for an additional transmitter, as is required for other types of motion detectors. Another advantage is that modern infrared detectors enable a large detection area that extends up to 180 °, so that a detector attached to a wall can detect a wide solid angle lying in front of this wall.
  • an infrared detector which focuses thermal radiation recorded from a monitored room with the aid of collecting optics onto a sensor which is sensitive in the infrared range.
  • the collecting optics consist of a large number of interconnected individual collecting lenses which are arranged in a semicircle around the detector. Each individual converging lens thus forms a strip-shaped segment of an axially segmented cylinder cutout.
  • the converging lenses have the structure of a Fresnel lens, so that a wide detection area is guaranteed not only radially to the cylindrical converging optics, but also axially along the strip-shaped converging lens.
  • a special feature of the infrared detector according to the aforementioned publication is that two mutually staggered mirrors in the vicinity of the optical axis of the collecting optics let rays incident directly to the sensor, on the other hand deflect the rays that are more distant from the optical axis so that they are at an acute angle to the optical axis Hit the axis on the sensor. This ensures that the sensor, which attains its highest sensitivity with perpendicularly incident radiation, also evaluates the very obliquely, ie up to 90 ° to the optical axis, rays with approximately the same sensitivity.
  • a detector of the type described is mounted on a wall in such a way that the axis of the cylindrical collecting optics is aligned vertically, it can at least extend the plane horizontally in front of it to the wall to which it is attached, monitor. There is a radiation object in the monitored space, this can only be registered by the sensor if it is located in the area of the main beam of one of the converging lenses. Because only a bundle of rays parallel to the main beam is focused on the sensor by the respective converging lens.
  • the bundles of rays also emanating from the radiation object and detected by the other converging lenses generate further focal points which, although they fall in the same focal plane in which the sensor is arranged, are however further away from the center of the sensor, the greater the angle of incidence forms the beam with the main beam of the respective lens.
  • the focal points of the individual segments also move along the focal plane on a straight line that runs through the sensor. As soon as the radiation object reaches the main beam of the next segment, its focal point falls on the sensor and this is repeated in both directions up to the last segment closest to the wall.
  • switching signals can be used to control an alarm system or, if necessary, to switch on the lighting in a room.
  • a radiation object enters the monitored space in the radial direction of the cylindrical collecting lens, it could move on a straight line which is called Bisector between the main rays of two adjacent segments. In this case it can be assumed that neither of the two focal points of these segments falls on the sensor, so that no signal can be generated.
  • the object of the invention is to design the motion detector so that a practically complete room monitoring can take place, so that in particular movements of a radiation object are also detected which are directed directly towards or away from the motion detector.
  • the solution according to the invention has the advantage that an already existing collecting optics can continue to be used unchanged, and only an additional deflecting optics has to be inserted.
  • Various alternative solutions that are relatively easy to implement are available for implementing the deflection optics.
  • the formation of the radiation maxima is irrelevant as long as it is ensured that they hit the sensor one after the other. In the case of punctiform and stripe-shaped radiation maxima, this is the case as soon as there is an optically effective distance between them. With radiation maxima arranged in a ring, the diameter of the rings must be relatively large in relation to the active area of the sensor.
  • the number of pulses that can be achieved per segment of the collecting optics can be increased not only by additional radiation maxima, but also by several sensor elements that are spatially separated from one another and assigned to a sensor.
  • An active surface of a sensor e.g. a lithium tantalate crystal can be understood. If the sensor elements are electrically connected to one another, each radiation maximum, once it has traveled through the space between two sensor elements, generates a signal on the subsequent sensor element upon entry and exit.
  • the sensor elements are normally connected in series, with a reverse-pole series connection being possible in special cases.
  • signals of different polarity are generated, so that the total amplitude between the amplitude peaks increases to twice the value.
  • Such arrangements are also used to form the difference, which makes it possible to supply the two sensor elements with rays from different segments of the collecting optics and thus also different areas of the monitored space, in order to thus eliminate all-effective radiation sources, such as solar radiation.
  • In Connection with the above invention would have to ensure that only one radiation maximum hits one of the two sensor elements at the same time, so that their signals do not compensate for one another.
  • the individual segments of the collecting optics can be realized in a known manner as collecting lenses or also with the aid of focusing concave mirrors.
  • the collecting optics also include any mirrors to be inserted, which are used to deflect at least some of the beams.
  • the Fresnel lens represents a particularly expedient collecting lens, since it enables a wide detection area, which extends particularly in the vertical direction in a motion detector of the present type.
  • a simple way of realizing the deflection optics is to arrange a diffraction grating in front of or behind the collecting optics.
  • the diffraction grating like the collecting optics, is positioned concentrically to the sensor.
  • each segment of the collecting optics is assigned a fixed number of grid columns (grid grid) or grid holes (cross grid).
  • a deflection corresponding to the diffraction grating can also be achieved with the aid of a diffraction screen, which would also have to be arranged on a surface which is concentric with the collecting optics.
  • columns or fine wires take the place of gaps, which in the same way enable the generation of radiation maxima by diffraction.
  • Another alternative to generating a plurality of radiation maxima is obtained by inserting one or more diffraction elements as deflection optics into the common beam path of all or at least several segments of the collecting optics, which are now no longer assigned to the individual segments of the collecting optics but to the sensor .
  • the position of the focal point relative to the sensor may have to be changed so that the focal point comes to lie in the area of the deflection optics.
  • the number of signals per segment of the collecting optics can be increased by the number of sensor elements. This is a similar effect achievable that one can optically share a relatively large active sensor element by interrupting the beam path between the collecting optics and the sensor by a cover element. If the interruption takes place in such a way that the rays in front of and behind the screen fall on a partial area of the sensor element, the number of signals is doubled.
  • the detector consists of a collecting optic 1, a diffraction grating 3, a mirror 4 and a sensor 5.
  • the collecting optic 1 is segmented in the vertical direction or axially so that each segment 2 forms its own collecting lens, all of which are closed focused their main beam parallel incident rays on a focal point, in the plane of which the sensor 5 is arranged.
  • FIG. 2 The illustration in FIG. 2 is intended to clarify the principle of operation of the diffraction grating 3. It is assumed that this is a diffraction grating 3 with a plurality of gaps 16 arranged in parallel.
  • the parallel rays 8 incident in parallel from a correspondingly distant radiation object to a main beam 6 are focused by a Fresnel lens 2. After emerging from the Fresnel lens 2, they meet the diffraction grating 3, with diffraction taking place in a known manner at each slit 16. In addition to the focal point that lies on the main beam 6, this results in further radiation maxima 10.
  • a two-dimensional cross grating with a diffraction spectrum known per se can also be used as the diffraction grating.
  • a radiation object 13 moves tangentially to the cylindrically curved collection optics 1
  • the focal points of all segments 2 of the collection optics also move as soon as they receive part of the radiation emanating from the radiation object 13 capture, along the focal plane 15.
  • a main beam 6 is first shown, which passes through a segment 2 arranged symmetrically to the optical axis and hits the sensor element 7 of the sensor 5 uninterrupted. All rays parallel to the main ray 6 generate a common focal point here.
  • an angular beam 9 is formed which is incident at an acute angle to the main beam of segment 2 and is deflected by the latter towards sensor element 7, but no longer strikes it. I.e. the focal point of the rays incident through the segment 2 has now migrated out of the sensor element 7.
  • a signal is produced. Another signal arises from the fact that the radiation object 13 in position B reaches the main beam 6 'of the adjacent segment 2' and thereby its focal point falls on the sensor element 7.
  • Trigger signal at sensor 5 is as small as possible. Because with a very small ⁇ S it can be assumed that a tangential movement 11 which can be registered also takes place in connection with a radial movement 12.
  • a signal is generated at the sensor 5 when a radiation maximum moving along the focal plane 15 strikes or leaves a sensor element.
  • the distance ⁇ X between the focal points of two segments 2 determines the distance ⁇ S.
  • the critical path ⁇ S can be reduced with otherwise identical optical conditions. In relation to the entire detection range of the collecting optics, this means an increase in the number of radiation maxima; an approximately equal distance between the radiation maxima is assumed.
  • a diffraction grating 3 which is arranged behind the collecting optics 1.
  • the diffraction grating which is preferably to be provided with diffraction slits, could in principle also be arranged in front of the collecting optics 1, but behind it it is in particular protected against contamination.
  • the diffraction grating has the effect that the focal points of all the heat rays incident through the segments 2 in parallel are quasi divided into a plurality of radiation maxima, so that the number of radiation maxima is thereby multiplied.
  • FIG. 3 there are only two further radiation maxima lying symmetrically to the main beam 6 10 drawn. However, it can be seen that this already reduces the distance between two adjacent radiation maxima to ⁇ X '. This also shortens the critical distance ⁇ S, but this is not shown. It can also be assumed that when the radiation object 13 approaches the collecting optics 1, the diffraction changes somewhat, and the radiation maxima are also shifted somewhat as a result.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Photometry And Measurement Of Optical Pulse Characteristics (AREA)
  • Geophysics And Detection Of Objects (AREA)
  • Burglar Alarm Systems (AREA)

Abstract

In motion alarms with segmented collecting optics, dead spaces occur between the individual focusing segments, in which a radiation object can be located without triggering a signal. These dead spaces are to be avoided in practice in the new motion alarm. …<??>For this purpose, deflection optics (3) are arranged behind the collecting optics (1), which in each case deflect a part of the beam of rays (8) incident in parallel with the main beam (6) of a segment (2), in such a manner that at least two radiation peaks are produced. These radiation peaks successively impinge on sensor elements (7) of the sensor (5) with a corresponding change in position of the radiation object (13). This reduces the size of the dead spaces to such an extent that, in practice, they no longer exist. …<??>The motion alarm is used for room surveillance inside and outside buildings. It can switch on illumination or trigger an alarm by signal transmission. …<IMAGE>…

Description

Die Erfindung betrifft einen Bewegungsmelder der im Oberbegriff des Anspruchs 1 genannten Art.The invention relates to a motion detector of the type mentioned in the preamble of claim 1.

Bei der Raumüberwachung sowohl innerhalb wie auch außerhalb von Gebäuden erfreuen sich Bewegungsmelder mit Infrarotdetektor zunehmender Beliebtheit. Als passive Detektoren sprechen sie unmittelbar auf Strahlungs­objekte an, die Wärmestrahlung abgeben. Ein solches Strahlungsobjekt ist z.B. auch ein Mensch, der in einen zu überwachenden Raum eindringt. Es wird somit kein zusätzlicher Sender benötigt, wie er bei Bewegungs­meldern anderer Art erforderlich ist. Ein weiterer Vorteil ist, daß moderne Infrarotdetektoren einen großen Erfassungsbereich ermöglichen, der bis zu 180 ° reicht, so daß ein an einer Wand angebrachter Detektor einen breiten vor dieser Wand liegenden Raumwinkel erfassen kann.Motion detectors with infrared detectors are becoming increasingly popular for room surveillance both inside and outside buildings. As passive detectors, they respond directly to radiation objects that emit thermal radiation. Such a radiation object is also a person, for example, who penetrates into a room to be monitored. There is therefore no need for an additional transmitter, as is required for other types of motion detectors. Another advantage is that modern infrared detectors enable a large detection area that extends up to 180 °, so that a detector attached to a wall can detect a wide solid angle lying in front of this wall.

Aus der EP-A2-0 113 468 ist ein Infrarotdetektor be­kannt, der aus einem überwachten Raum aufgenommene Wärmestrahlung mit Hilfe einer Sammeloptik auf einen im Infrarotbereich empfindlichen Sensor fokussiert. Die Sammeloptik besteht aus einer Vielzahl miteinander verbundener einzelner Sammellinsen, die im Halbkreis um den Detektor angeordnet sind. Jede einzelne Sammellinse bildet somit ein streifenförmiges Segment eines axial segmentierten Zylinderausschnittes. Die Sammellinsen haben dabei die Struktur einer Fresnel-Linse, so daß nicht nur radial zur zylindrischen Sammeloptik, sondern auch axial entlang der streifenförmigen Sammellinse ein breiter Erfassungsbereich gewährleistet ist.From EP-A2-0 113 468 an infrared detector is known which focuses thermal radiation recorded from a monitored room with the aid of collecting optics onto a sensor which is sensitive in the infrared range. The collecting optics consist of a large number of interconnected individual collecting lenses which are arranged in a semicircle around the detector. Each individual converging lens thus forms a strip-shaped segment of an axially segmented cylinder cutout. The converging lenses have the structure of a Fresnel lens, so that a wide detection area is guaranteed not only radially to the cylindrical converging optics, but also axially along the strip-shaped converging lens.

Eine Besonderheit des Infrarotdetektors nach der vorge­nannten Veröffentlichung besteht darin, daß zwei zu­einander versetzt angeordnete Spiegel im Nahbereich der optischen Achse der Sammeloptik einfallende Strahlen unmittelbar zum Sensor durchlassen, dagegen die von der optischen Achse entfernteren Strahlen so umlenken, daß diese in einem spitzeren Winkel zur optischen Achse auf den Sensor treffen. Hierdurch wird erreicht, daß der Sensor, der seine höchste Empfindlichkeit bei senkrecht einfallender Strahlung erlangt, auch die sehr schräg, also bis zu 90 ° zur optischen Achse einfallenden Strahlen mit näherungsweise gleicher Empfindlichkeit bewertet.A special feature of the infrared detector according to the aforementioned publication is that two mutually staggered mirrors in the vicinity of the optical axis of the collecting optics let rays incident directly to the sensor, on the other hand deflect the rays that are more distant from the optical axis so that they are at an acute angle to the optical axis Hit the axis on the sensor. This ensures that the sensor, which attains its highest sensitivity with perpendicularly incident radiation, also evaluates the very obliquely, ie up to 90 ° to the optical axis, rays with approximately the same sensitivity.

Geht man davon aus, daß ein Detektor der beschriebenen Art so an einer Wand montiert ist, daß die Achse der zylindrischen Sammeloptik vertikal ausgerichtet ist, so kann er zumindest die sich horizontal vor ihm erstrek­kende Ebene bis hin zur Wand, an der er befestigt ist, überwachen. Befindet sich ein Strahlungsobjekt in dem überwachten Raum, so kann dieses von dem Sensor nur dann registriert werden, wenn es sich im Bereich des Haupt­strahles einer der Sammellinsen befindet. Denn nur ein zum Hauptstrahl paralleles Strahlenbündel wird von der jeweiligen Sammellinse auf den Sensor fokussiert. Die ebenfalls vom Strahlungsobjekt ausgehenden, von den anderen Sammellinsen erfaßten Strahlenbündel erzeugen weitere Brennpunkte, die zwar in die gleiche Brennebene fallen, in der auch der Sensor angeordnet ist, jedoch um so weiter vom Mittelpunkt des Sensors entfernt sind, je größer der Einfallwinkel ist, den das Strahlenbündel mit dem Hauptstrahl der jeweiligen Linse bildet.If one assumes that a detector of the type described is mounted on a wall in such a way that the axis of the cylindrical collecting optics is aligned vertically, it can at least extend the plane horizontally in front of it to the wall to which it is attached, monitor. There is a radiation object in the monitored space, this can only be registered by the sensor if it is located in the area of the main beam of one of the converging lenses. Because only a bundle of rays parallel to the main beam is focused on the sensor by the respective converging lens. The bundles of rays also emanating from the radiation object and detected by the other converging lenses generate further focal points which, although they fall in the same focal plane in which the sensor is arranged, are however further away from the center of the sensor, the greater the angle of incidence forms the beam with the main beam of the respective lens.

Bewegt sich nun das Strahlungsobjekt ebenerdig parallel zur Wand des Detektors bzw. tangential zur zylindrischen Sammeloptik, so bewegen sich auch die Brennpunkte der einzelnen Segmente entlang der Brennebene auf einer Geraden, die durch den Sensor verläuft. Sobald das Strahlungsobjekt den Hauptstrahl des nächsten Segmentes erreicht, fällt dessen Brennpunkt auf den Sensor und das wiederholt sich in beiden Richtungen jeweils bis zum letzten, der Wand nächstliegenden Segment.If the radiation object now moves at ground level parallel to the wall of the detector or tangentially to the cylindrical collecting optics, the focal points of the individual segments also move along the focal plane on a straight line that runs through the sensor. As soon as the radiation object reaches the main beam of the next segment, its focal point falls on the sensor and this is repeated in both directions up to the last segment closest to the wall.

Bei jedem Auftreffen eines Brennpunktes auf der aktiven Kristallfläche eines Sensors, und auch sobald der Brennpunkt nach Durchqueren der Kristallfläche diese wieder verläßt, entsteht ein elektrisches Signal das als Schaltsignal verwertbar ist. Mit diesen Schaltsignalen läßt sich eine Alarmanlage steuern oder ggf. auch die Beleuchtung eines Raumes einschalten.Every time a focal point strikes the active crystal surface of a sensor, and also as soon as the focal point leaves the crystal surface after crossing it, an electrical signal is generated which can be used as a switching signal. These switching signals can be used to control an alarm system or, if necessary, to switch on the lighting in a room.

Betritt ein Strahlungsobjekt den überwachten Raum in radialer Richtung zum zylindrischen Sammelobjektiv, so könnte es sich auf einer Geraden bewegen, die als Winkelhalbierende zwischen den Hauptstrahlen zweier benachbarter Segmente liegt. In diesem Fall ist davon auszugehen, daß keiner der beiden Brennpunkte dieser Segmente auf den Sensor fällt, so daß auch kein Signal entstehen kann.If a radiation object enters the monitored space in the radial direction of the cylindrical collecting lens, it could move on a straight line which is called Bisector between the main rays of two adjacent segments. In this case it can be assumed that neither of the two focal points of these segments falls on the sensor, so that no signal can be generated.

Aufgabe der Erfindung ist es, den Bewegungsmelder so zu gestalten, daß eine praktisch lückenlose Raumüberwachung erfolgen kann, so daß insbesondere auch solche Bewe­gungungen eines Strahlungsobjektes erfaßt werden, die unmittelbar auf den Bewegungsmelder zu oder von diesem weggerichtet sind.The object of the invention is to design the motion detector so that a practically complete room monitoring can take place, so that in particular movements of a radiation object are also detected which are directed directly towards or away from the motion detector.

Diese Aufgabe wird durch die im Anspruch 1 gekennzeich­neten Merkmale gelöst. Zweckmäßige Ausgestaltungen und Weiterbildungen des Erfindungsgegenstandes sind in den Unteransprüchen genannt.This object is achieved by the features characterized in claim 1. Appropriate refinements and developments of the subject matter of the invention are mentioned in the subclaims.

Man könnte sich vorstellen, die Aufgabe dadurch zu lösen, daß man die Zahl der fokussierenden Elemente erhöht, um mehr bzw. dichter aufeinanderfolgende Brenn­punkte zu erhalten. Dies würde aber die ohnehin schwer herzustellende Sammeloptik weiter verkomplizieren und zu besonders teueren Werkzeugen führen.One could envision solving the problem by increasing the number of focusing elements in order to obtain more or closer successive focal points. However, this would further complicate the collecting optics, which are difficult to manufacture anyway, and would lead to particularly expensive tools.

Die erfindungsgemäße Lösung hat den Vorteil, daß eine bereits existierende Sammeloptik unverändert weiterver­wendbar ist, und lediglich eine zusätzliche Ablenkoptik eingefügt werden muß. Zur Realisierung der Ablenkoptik bieten sich verschiedene, relativ einfach auszuführende Lösungsalternativen an.The solution according to the invention has the advantage that an already existing collecting optics can continue to be used unchanged, and only an additional deflecting optics has to be inserted. Various alternative solutions that are relatively easy to implement are available for implementing the deflection optics.

Die Ausbildung der Strahlungsmaxima ist solange belang­los, als sichergestellt ist, daß diese nacheinander auf den Sensor auftreffen. Bei punktförmigen und streifen­förmigen Strahlungsmaxima ist das ohnehin gegeben, sobald ein optisch wirksamer Abstand zwischen ihnen vorliegt. Bei ringförmig angeordneten Strahlungsmaxima muß der Durchmesser der Ringe relativ groß im Verhältnis zur aktiven Fläche des Sensors sein.The formation of the radiation maxima is irrelevant as long as it is ensured that they hit the sensor one after the other. In the case of punctiform and stripe-shaped radiation maxima, this is the case as soon as there is an optically effective distance between them. With radiation maxima arranged in a ring, the diameter of the rings must be relatively large in relation to the active area of the sensor.

Die Zahl der Impulse, die pro Segment der Sammeloptik erzielbar ist, läßt sich nicht nur durch zusätzliche Strahlungsmaxima, sondern auch durch mehrere, räumlich voneinander getrennte, einem Sensor zugeordnete Sensor­elemente erhöhen. Unter einem Sensorelement soll jeweils eine aktiv wirksame Fläche eines Sensors, z.B. ein Lithium-Tantalat-Kristall verstanden werden. Verbindet man die Sensorelemente elektrisch miteinander, so erzeugt jedes Strahlungsmaximum, nachdem es den Zwi­schenraum zwischen zwei Sensorelementen durchwandert hat, auf dem nachfolgenden Sensorelement erneut ein Signal beim Ein- und Austritt.The number of pulses that can be achieved per segment of the collecting optics can be increased not only by additional radiation maxima, but also by several sensor elements that are spatially separated from one another and assigned to a sensor. An active surface of a sensor, e.g. a lithium tantalate crystal can be understood. If the sensor elements are electrically connected to one another, each radiation maximum, once it has traveled through the space between two sensor elements, generates a signal on the subsequent sensor element upon entry and exit.

Die Sensorelemente werden normalerweise in Reihe ge­schaltet, wobei im Sonderfall auch eine gegenpolige Reihenschaltung möglich ist. Dadurch die Gegenpoligkeit werden jeweils Signale unterschiedlicher Polarität erzeugt, so daß die Gesamtamplitude zwischen den Ampli­tudenspitzen auf den doppelten Wert ansteigt. Man verwendet derartige Anordnungen auch zur Differenz­bildung, die es ermöglicht, den beiden Sensorelementen Strahlen von verschiedenen Segmenten der Sammeloptik und damit auch verschiedenen Bereichen des überwachten Raumes zuzuführen, um somit gesamtwirksame Strahlungs­quellen, wie z.B. Sonneneinstrahlung zu eliminieren. In Verbindung mit der vorstehenden Erfindung müßte dafür gesorgt werden, daß zur gleichen Zeit jeweils nur ein Strahlungsmaximum auf eines der beiden Sensorelemente trifft, damit sich deren Signale nicht gegenseitig kompensieren.The sensor elements are normally connected in series, with a reverse-pole series connection being possible in special cases. As a result of the opposite polarity, signals of different polarity are generated, so that the total amplitude between the amplitude peaks increases to twice the value. Such arrangements are also used to form the difference, which makes it possible to supply the two sensor elements with rays from different segments of the collecting optics and thus also different areas of the monitored space, in order to thus eliminate all-effective radiation sources, such as solar radiation. In Connection with the above invention would have to ensure that only one radiation maximum hits one of the two sensor elements at the same time, so that their signals do not compensate for one another.

Um eine quasi lückenlose Überwachung zu gewährleisten, ist es von Vorteil, den Abstand zwischen den Strahlungs­maxima einerseits, sowie den Abstand und die Breite der Sensorelemente andererseits, so zu optimieren, daß vorzugsweise jedes Maximum ab einer vorgegebenen Ampli­tude beim Auftreffen auf und Austreten aus einem der Sensorelemente je ein separates Signal auslöst. Ein dichtes Aufeinanderfolgen der einzelnen Maxima stellt sicher, daß jede Bewegung in tangentialer Richtung zu einem Signal am Sensor führt. Da es in der Praxis nicht möglich ist eine radiale Bewegung völlig ohne tangen­tiale Komponente auszuführen, weil schon der schwankende Gang einer Person eine solche bewirkt, wird der Bewe­gungsmelder auch solche sicher erfassen.In order to ensure a virtually complete monitoring, it is advantageous to optimize the distance between the radiation maxima on the one hand, and the distance and the width of the sensor elements on the other hand, so that preferably each maximum from a predetermined amplitude when it strikes and exits one of the Sensor elements each trigger a separate signal. A close succession of the individual maxima ensures that every movement in the tangential direction leads to a signal at the sensor. Since it is not possible in practice to carry out a radial movement completely without a tangential component, because the fluctuating gait of a person causes such a movement, the motion detector will also reliably detect it.

Die einzelnen Segmente der Sammeloptik können in be­kannter Weise als Sammellinsen oder auch mit Hilfe von fokussierenden Hohlspiegeln realisiert werden. Zur Sammeloptik werden auch ggf. einzufügende Spiegel gezählt, die zur Umlenkung zumindest eines Teiles der Strahlen dienen. Eine besonders zweckmäßige Sammellinse stellt die Fresnel-Linse dar, da sie einen breiten Erfassungsbereich ermöglicht, der sich bei einem Bewe­gungsmelder der vorliegenden Art besonders in vertikaler Richtung erstreckt.The individual segments of the collecting optics can be realized in a known manner as collecting lenses or also with the aid of focusing concave mirrors. The collecting optics also include any mirrors to be inserted, which are used to deflect at least some of the beams. The Fresnel lens represents a particularly expedient collecting lens, since it enables a wide detection area, which extends particularly in the vertical direction in a motion detector of the present type.

Eine einfache Möglichkeit zur Realisierung der Ablenk­optik besteht in der Anordnung eines Beugungsgitters vor oder hinter der Sammeloptik. Das Beugungsgitter ist dabei, wie die Sammeloptik, konzentrisch zum Sensor positioniert.A simple way of realizing the deflection optics is to arrange a diffraction grating in front of or behind the collecting optics. The diffraction grating, like the collecting optics, is positioned concentrically to the sensor.

Die Gestaltung des Beugungsgitters richtet sich nach der Zahl und dem Abstand der einzelnen Strahlungsmaxima. Zur Optimierung ist jedem Segment der Sammeloptik eine fest vorgegebene Zahl von Gitterspalten (Strichgitter) bzw. Gitterlöchern (Kreuzgitter) zugeordnet.The design of the diffraction grating depends on the number and the distance of the individual radiation maxima. For optimization purposes, each segment of the collecting optics is assigned a fixed number of grid columns (grid grid) or grid holes (cross grid).

Eine dem Beugungsgitter entsprechende Ablenkung läßt sich auch mit Hilfe eines Beugungsschirms erzielen, wobei auch dieser an einer zur Sammeloptik konzen­trischen Fläche anzuordnen wäre. An die Stelle von Spalten treten in diesem Fall Balken bzw. feine Drähte, die in gleicher Weise durch Beugung die Erzeugung von Strahlungsmaxima ermöglichen.A deflection corresponding to the diffraction grating can also be achieved with the aid of a diffraction screen, which would also have to be arranged on a surface which is concentric with the collecting optics. In this case, columns or fine wires take the place of gaps, which in the same way enable the generation of radiation maxima by diffraction.

Eine weitere Alternative zur Erzeugung mehrerer Strah­lungsmaxima ergibt sich, wenn man in den gemeinsamen Strahlenverlauf von allen oder zumindest mehreren Segmenten der Sammeloptik unmittelbar vor dem Sensor ein oder mehrere Beugungselemente als Ablenkoptik einfügt, die nun nicht mehr den einzelnen Segmenten der Sammel­optik sondern dem Sensor zugeordnet sind. Hierbei muß ggf. die Lage des Brennpunktes zum Sensor so geändert werden, daß der Brennpunkt im Bereich der Ablenkoptik zu liegen kommt.Another alternative to generating a plurality of radiation maxima is obtained by inserting one or more diffraction elements as deflection optics into the common beam path of all or at least several segments of the collecting optics, which are now no longer assigned to the individual segments of the collecting optics but to the sensor . Here, the position of the focal point relative to the sensor may have to be changed so that the focal point comes to lie in the area of the deflection optics.

Wie bereits erläutert, läßt sich die Zahl der Signale pro Segment der Sammeloptik durch die Zahl der Sensor­elemente erhöhen. Ein gleichartiger Effekt ist dadurch erzielbar, daß man ein relativ großes aktives Sensorele­ment optisch teilt, indem man den Strahlenverlauf zwischen der Sammeloptik und dem Sensor durch ein Abdeckelement unterbricht. Erfolgt die Unterbrechung derart, daß die Strahlen vor und hinter dem Schirm auf jeweils einen Teilbereich des Sensorelementes fallen, so wird die Zahl der Signal verdoppelt.As already explained, the number of signals per segment of the collecting optics can be increased by the number of sensor elements. This is a similar effect achievable that one can optically share a relatively large active sensor element by interrupting the beam path between the collecting optics and the sensor by a cover element. If the interruption takes place in such a way that the rays in front of and behind the screen fall on a partial area of the sensor element, the number of signals is doubled.

Ausführungsbeispiele der Erfindung sind im folgenden näher beschrieben und in den Zeichnungen dargestellt.Embodiments of the invention are described in more detail below and shown in the drawings.

Es zeigen:

  • Figur 1: Den Detektor von oben gesehen mit Blickrich­tung auf die Oberkante der Sammeloptik und des Beugungsgitters,
  • Figur 2: eine vergrößerte Teildarstellung des Detektors seitlich im Schnitt entlang der Schnittlinie AB nach Figur 1,
  • Figur 3: den Strahlungsverlauf vor und innerhalb des Detektors bei Bewegungen eines Strahlungs­objektes in tangentialer Richtung.
Show it:
  • FIG. 1: the detector seen from above with a view of the upper edge of the collecting optics and the diffraction grating,
  • FIG. 2: an enlarged partial representation of the detector laterally in section along the section line AB according to FIG. 1,
  • Figure 3: the radiation path in front of and within the detector when a radiation object moves in the tangential direction.

Wie Figur 1 zeigt, besteht der Detektor aus einer Sammeloptik 1, einem Beugungsgitter 3, einem Spiegel 4 und einem Sensor 5. Die Sammeloptik 1 ist in vertikaler Richtung bzw. axial so segmentiert, daß jedes Segment 2 eine eigene Sammellinse bildet, die alle zu ihrem Hauptstrahl parallel einfallenden Strahlen auf einen Brennpunkt fokussiert, in dessen Ebene der Sensor 5 angeordnet ist. Die beiden zueinander versetzt ange­ordneten Spiegel 4 übernehmen hierbei lediglich eine Hilfsfunktion. Sie dienen dazu, auf den Sensor treffende Strahlen, die in einem Winkel von etwa 45 bis 90 ° zur optischen Achse 14 des Sensors einfallen, so umzulenken, daß sie nahezu senkrecht, aber zumindest in einem spitzeren Winkel zur optischen Achse 14 auf ein Sensor­element 7 des Sensors 5 auftreffen. Da die Spiegel 4 in Verbindung mit der vorliegenden Erfindung keine Bedeu­tung haben, sondern lediglich die Darstellung des Strahlenverlaufs erschweren, bleiben sie im Rahmen der weiteren Beschreibung unberücksichtigt.As FIG. 1 shows, the detector consists of a collecting optic 1, a diffraction grating 3, a mirror 4 and a sensor 5. The collecting optic 1 is segmented in the vertical direction or axially so that each segment 2 forms its own collecting lens, all of which are closed focused their main beam parallel incident rays on a focal point, in the plane of which the sensor 5 is arranged. The two mirrors 4, which are arranged offset with respect to one another, only take on one Auxiliary function. They are used to deflect rays incident on the sensor, which are incident at an angle of approximately 45 to 90 ° to the optical axis 14 of the sensor, in such a way that they are almost perpendicular, but at least at an acute angle to the optical axis 14 onto a sensor element 7 of sensor 5 hit. Since the mirrors 4 have no meaning in connection with the present invention, but merely complicate the representation of the beam path, they are not taken into account in the further description.

Die Darstellung in Figur 2 soll die prinzipielle Wir­kungsweise des Beugungsgitters 3 verdeutlichen. Es sei angenommen, daß es sich hierbei um ein Beugungsgitter 3 mit einer Vielzahl parallel angeordneter Spalte 16 handelt. Die von einem entsprechend weit entfernten Strahlungsobjekt zu einem Hauptstrahl 6 parallel ein­fallenden Parallelstrahlen 8 werden durch eine Fresnel-Linse 2 fokussiert. Nach dem Austritt aus der Fresnel-Linse 2 treffen sie auf das Beugungsgitter 3, wobei an jedem Spalt 16 in bekannter Weise eine Beugung stattfindet. Hierdurch entstehen neben dem Brennpunkt, der auf dem Hauptstrahl 6 liegt, weitere Strahlungs­maxima 10.The illustration in FIG. 2 is intended to clarify the principle of operation of the diffraction grating 3. It is assumed that this is a diffraction grating 3 with a plurality of gaps 16 arranged in parallel. The parallel rays 8 incident in parallel from a correspondingly distant radiation object to a main beam 6 are focused by a Fresnel lens 2. After emerging from the Fresnel lens 2, they meet the diffraction grating 3, with diffraction taking place in a known manner at each slit 16. In addition to the focal point that lies on the main beam 6, this results in further radiation maxima 10.

Als Beugungsgitter kann auch ein zweidimensionales Kreuzgitter mit an sich bekanntem Beugungsspektrum verwendet werden.A two-dimensional cross grating with a diffraction spectrum known per se can also be used as the diffraction grating.

Bewegt sich ein Strahlungsobjekt 13, wie in Figur 3 dargestellt, tangential zur zylindrisch gebogenen Sammeloptik 1, so bewegen sich auch die Brennpunkte aller Segmente 2 der Sammeloptik, sobald sie einen Teil der vom Strahlungsobjekt 13 ausgehenden Strahlung erfassen, entlang der Brennebene 15. Zur Verdeutlichung dieses Vorgangs ist zunächst ein Hauptstrahl 6 darge­stellt, der ein symmetrisch zur optischen Achse ange­ordnetes Segment 2 durchläuft und ungebrochen auf das Sensorelement 7 des Sensors 5 auftrifft. Alle zum Hauptstrahl 6 parallelen Strahlen erzeugen hier einen gemeinsamen Brennpunkt.If a radiation object 13, as shown in FIG. 3, moves tangentially to the cylindrically curved collection optics 1, the focal points of all segments 2 of the collection optics also move as soon as they receive part of the radiation emanating from the radiation object 13 capture, along the focal plane 15. To clarify this process, a main beam 6 is first shown, which passes through a segment 2 arranged symmetrically to the optical axis and hits the sensor element 7 of the sensor 5 uninterrupted. All rays parallel to the main ray 6 generate a common focal point here.

Bewegt sich das Strahlungsobjekt 13 nun von der Position A zur Position B, so entsteht ein Winkelstrahl 9, der im spitzen Winkel zum Hauptstrahl des Segmentes 2 einfällt und von diesem zwar zum Sensorelement 7 hin abgelenkt wird, aber nicht mehr auf dieses auftrifft. D.h. der Brennpunkt, der durch das Segment 2 einfallenden Strah­len ist nunmehr aus dem Sensorelement 7 herausgewandert. Beim Austreten aus dem Sensorelement 7 ist dabei ein Signal entstanden. Ein weitereres Signal entsteht dadurch, daß das Strahlungsobjekt 13 in der Position B den Hauptstrahl 6′ des benachbarten Segmentes 2′ erreicht und dadurch dessen Brennpunkt auf das Sensor­element 7 fällt.If the radiation object 13 now moves from position A to position B, an angular beam 9 is formed which is incident at an acute angle to the main beam of segment 2 and is deflected by the latter towards sensor element 7, but no longer strikes it. I.e. the focal point of the rays incident through the segment 2 has now migrated out of the sensor element 7. When the sensor element 7 emerges, a signal is produced. Another signal arises from the fact that the radiation object 13 in position B reaches the main beam 6 'of the adjacent segment 2' and thereby its focal point falls on the sensor element 7.

Sollte das Strahlungsobjekt 13 seinen Weg in gleicher Richtung fortsetzen, so würde es nach einer bestimmten Strecke s auf den Hauptstrahl des nachfolgenden Seg­mentes treffen, wobei nun dessen Brennpunkt auf dem Sensorelement 7 zu liegen kommt, während der Brennpunkt des vorhergehenden Segmentes 2′ wiederum aus dem Bereich des Sensorelementes 7 herausgewandert ist. Der gleiche Vorgang wiederholt sich entlang der ganzen Sammeloptik.Should the radiation object 13 continue its path in the same direction, it would hit the main beam of the following segment after a certain distance s, with its focal point now coming to rest on the sensor element 7, while the focal point of the previous segment 2 'again from the Area of the sensor element 7 has migrated out. The same process is repeated along the entire collection optics.

Für eine möglichst lückenlose Erfassung ist es erforder­lich, daß die tangentiale Wegstrecke ΔS, die das Strahlungsobjekt 13 zurückzulegen hat, um ein erneutes Signal am Sensor 5 auszulösen, möglichst klein ist. Denn bei sehr kleinem ΔS kann man davon ausgehen, daß auch in Verbindung mit einer radialen Bewegung 12 eine registrierbare tangentiale Bewegung 11 erfolgt.In order for the detection to be as complete as possible, it is necessary for the tangential path distance ΔS which the radiation object 13 has to cover to be repeated Trigger signal at sensor 5 is as small as possible. Because with a very small ΔS it can be assumed that a tangential movement 11 which can be registered also takes place in connection with a radial movement 12.

Am Sensor 5 entsteht jeweils dann ein Signal, wenn ein sich entlang der Brennebene 15 bewegendes Strahlungs­maximum auf ein Sensorelement auftrifft oder dieses verläßt. Ohne Ablenkoptik bestimmt der Abstand ΔX zwischen den Brennpunkten zweier Segmente 2 die Weg­strecke ΔS. Durch Verringerung des Abstandes zwischen zwei aufeinanderfolgenden Strahlungsmaxima kann bei sonst gleichen optischen Verhältnissen die kritische Wegstrecke ΔS reduziert werden. Bezogen auf den gesamten Erfassungsbereich der Sammeloptik bedeutet das eine Erhöhung der Zahl der Strahlungsmaxima; wobei ein näherungsweise gleicher Abstand zwischen den Strahlungs­maxima vorausgesetzt ist.A signal is generated at the sensor 5 when a radiation maximum moving along the focal plane 15 strikes or leaves a sensor element. Without deflection optics, the distance ΔX between the focal points of two segments 2 determines the distance ΔS. By reducing the distance between two successive radiation maxima, the critical path ΔS can be reduced with otherwise identical optical conditions. In relation to the entire detection range of the collecting optics, this means an increase in the number of radiation maxima; an approximately equal distance between the radiation maxima is assumed.

Da einer Vermehrung der Strahlungsmaxima durch ver­stärkte Segmentierung der Sammeloptik 1 Grenzen gesetzt sind, läßt sich diese auf einfache Weise durch ein Beugungsgitter 3 erzielen, das hinter der Sammeloptik 1 angeordnet wird. Das vorzugsweise mit Beugungsspalten zu versehende Beugungsgitter könnte zwar im Prinzip auch vor der Sammeloptik 1 angeordnet werden, es ist hinter dieser aber insbesondere vor Verschmutzung geschützt.Since there are limits to an increase in the radiation maxima due to increased segmentation of the collecting optics 1, this can be achieved in a simple manner by means of a diffraction grating 3 which is arranged behind the collecting optics 1. The diffraction grating, which is preferably to be provided with diffraction slits, could in principle also be arranged in front of the collecting optics 1, but behind it it is in particular protected against contamination.

Das Beugungsgitter bewirkt, daß die Brennpunkte aller durch die Segmente 2 parallel einfallender Wärmestrahlen quasi in mehrere Strahlungsmaxima aufgeteilt werden, so daß sich hierdurch die Zahl der Strahlungsmaxima ver­vielfacht. In Figur 3 sind lediglich zwei weitere, symmetrisch zum Hauptstrahl 6 liegende Strahlungsmaxima 10 eingezeichnet. Es ist jedoch erkennbar, daß sich bereits hierdurch der Abstand zwischen zwei benachbarten Strahlungsmaxima auf ΔX′ vermindert. Somit verkürzt sich auch die kritische Wegstrecke ΔS, was aber nicht dargestellt ist. Es ist außerdem davon auszugehen, daß sich bei einer Annäherung des Strahlenobjektes 13 an die Sammeloptik 1 die Beugung etwas ändert, und sich hier­durch die Strahlungsmaxima zusätzlich noch etwas ver­lagern.The diffraction grating has the effect that the focal points of all the heat rays incident through the segments 2 in parallel are quasi divided into a plurality of radiation maxima, so that the number of radiation maxima is thereby multiplied. In FIG. 3 there are only two further radiation maxima lying symmetrically to the main beam 6 10 drawn. However, it can be seen that this already reduces the distance between two adjacent radiation maxima to ΔX '. This also shortens the critical distance ΔS, but this is not shown. It can also be assumed that when the radiation object 13 approaches the collecting optics 1, the diffraction changes somewhat, and the radiation maxima are also shifted somewhat as a result.

Auf eine detaillierte Darstellung der übrigen Lösungs­alternativen anhand von Zeichnungen wird verzichtet, da im wesentlichen die vorstehend beschriebenen Fakten auch hier zur Anwendung gelangen.A detailed description of the other alternative solutions based on drawings is omitted, since essentially the facts described above are also used here.

Claims (12)

1. Bewegungsmelder mit einem Infrarotdetektor, der die aus einem überwachten Raum aufgenommene Wärmestrah­lung mit Hilfe einer Sammeloptik auf mindestens einen im Infrarotbereich empfindlichen Sensor fokussiert und dieser bei einer vorgegebenen Änderung der empfangenen Infrarotstrahlung ein Signal abgibt, das zur Auslösung einer Schaltfunktion dient, wobei die Sammeloptik aus einem axial segmentierten Zylinderausschnitt besteht und jedes Segment eine mit ihrem Hauptstrahl auf den Sensor gerichtete Fokussierung bewirkt, dadurch gekennzeichnet, daß vor oder hinter der Sammeloptik (1) eine Ablenkoptik (3) angeordnet ist, die jeweils einen Teil des parallel zum Hauptstrahl (6) eines Segmentes (2) einfallenden Strahlenbündels (8) so ablenkt, daß mindestens zwei Strahlungsmaxima entstehen, die bei einer entsprechenden Positionsänderung des Strahlungsobjektes (13) nachei­nander auf den Sensor (5) treffen.1. Motion detector with an infrared detector, which focuses the heat radiation recorded from a monitored room with the aid of collecting optics onto at least one sensor which is sensitive in the infrared range and which emits a signal when a predetermined change in the received infrared radiation is received, which is used to trigger a switching function, the collecting optics consists of an axially segmented cylinder cutout and each segment effects focusing with its main beam onto the sensor, characterized in that a deflecting optic (3) is arranged in front of or behind the collecting optics (1), each of which is part of the parallel to the main beam (6 ) of a segment (2) deflects the incident beam (8) in such a way that at least two radiation maxima arise, which hit the sensor (5) in succession when the radiation object (13) changes position accordingly. 2. Bewegungsmelder nach Anspruch 1, dadurch gekenn­zeichnet, daß die Strahlungsmaxima punkt- , ring- oder streifenförmig sind, und ihr gegenseitiger Abstand vor­zugsweise etwa gleich ist.2. Motion detector according to claim 1, characterized in that the radiation maxima are point, ring or strip-shaped, and their mutual distance is preferably approximately the same. 3. Bewegungsmelder nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß der Sensor (5) mindestens zwei räumlich voneinander getrennte Sensor­elemente (7) besitzt, die elektrisch miteinander verbun­den sind.3. Motion detector according to one of the preceding claims, characterized in that the sensor (5) has at least two spatially separate sensor elements (7) which are electrically connected to one another. 4. Bewegungsmelder nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Sensorelemen­te (7) elektrisch, vorzugsweise gegenpolig, in Reihe geschaltet sind.4. Motion detector according to one of the preceding claims, characterized in that the sensor elements (7) are electrically, preferably in opposite poles, connected in series. 5. Bewegungsmelder nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß der Abstand zwischen den Strahlungsmaxima einerseits und die Flächen der Sensorelemente (7) andererseits jeweils so optimiert sind, daß die meisten oder alle Maxima ab einer vorge­gebenen Amplitude bei Auftreffen auf und Austreten aus einem der Sensorelemente (7) ein separates Signal auslösen.5. Motion detector according to one of the preceding claims, characterized in that the distance between the radiation maxima on the one hand and the surfaces of the sensor elements (7) on the other hand are each optimized so that most or all of the maxima from a predetermined amplitude when striking and emerging from a the sensor elements (7) trigger a separate signal. 6. Bewegungsmelder nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Segmente der Sammeloptik (1) jeweils als Linsen, vorzugsweise als Fresnel-Linsen ausgebildet sind und eine Umlenkung bestimmter Strahlen mit Hilfe von Spiegeln (7) erfolgt.6. Motion detector according to one of the preceding claims, characterized in that the segments of the collecting optics (1) are each designed as lenses, preferably as Fresnel lenses, and a deflection of certain beams with the aid of mirrors (7). 7. Bewegungsmelder nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Ablenkoptik (3) aus einem vor oder hinter der Sammeloptik (1) angeordneten Beugungsgitter besteht, das auf einer zur zylindrischen Sammeloptik (1) koaxialen Fläche ange­ordnet ist.7. Motion detector according to one of the preceding claims, characterized in that the deflecting optics (3) consists of a diffraction grating arranged in front of or behind the collecting optics (1) which is arranged on a surface which is coaxial with the cylindrical collecting optics (1). 8. Bewegungsmelder nach Anspruch 7, dadurch gekenn­zeichnet, daß jedem Segment 2 der Sammeloptik (1) eine fest vorgegebene Zahl von Gitterspalten oder Gitter­löchern zugeordnet ist.8. Motion detector according to claim 7, characterized in that each segment 2 of the collecting optics (1) is assigned a predetermined number of grid columns or grid holes. 9. Bewegungsmelder nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß die Ablenkoptik (3) aus einem vor oder hinter der Sammeloptik (1) angeordneten Beugungsschirm besteht, der auf einer zur zylindrischen Sammeloptik (1) koaxialen Fläche angeordnet ist und dessen Schirmelemente aus dünnen Fäden oder Drähten oder Durchbrüchen bestehen.9. Motion detector according to one of claims 1 to 6, characterized in that the deflecting optics (3) consists of a diffraction screen arranged in front of or behind the collecting optics (1), which is arranged on a surface coaxial to the cylindrical collecting optics (1) and its screen elements consist of thin threads or wires or openings. 10. Bewegungsmelder nach Anspruch 9, dadurch gekennzeichnet, daß jedem Segment (2) der Sammeloptik (1) eine fest vorgegebene Zahl von Schirmelementen zugeordnet ist.10. Motion detector according to claim 9, characterized in that each segment (2) of the collecting optics (1) is assigned a fixed predetermined number of screen elements. 11. Bewegungsmelder nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß für mehrere oder alle Segmente (2) der Sammeloptik (1) gemeinsam ein oder mehrere Beugungselemente als Ablenkoptik (3) in den Strahlenverlauf zwischen der Sammeloptik (1) und dem Sensor (5) eingefügt sind.11. Motion detector according to one of claims 1 to 6, characterized in that for several or all segments (2) of the collecting optics (1) together one or more diffraction elements as deflecting optics (3) in the beam path between the collecting optics (1) and the sensor (5) are inserted. 12. Bewegungsmelder nach einem der Ansprüche 1 bis 6, daß für mehrere oder alle Segmente (2) der Sammel­optik (1) gemeinsam ein Abdeckelement in den Strahlen­verlauf zwischen der Sammeloptik (1) und den Sensor (5) eingefügt ist, das die von einem Segment (2) ausgehenden Strahlen innerhalb eines mittleren Teilbereiches eines Sensorelementes (7) unterdrückt.12. Motion detector according to one of claims 1 to 6, that for several or all segments (2) of the collecting optics (1) together a cover element in the beam path between the collecting optics (1) and the sensor (5) is inserted, which by a Segment (2) suppressing outgoing rays within a central portion of a sensor element (7).
EP88120222A 1987-12-11 1988-12-03 Motion alarm with an infrared detector Withdrawn EP0319876A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19873742031 DE3742031A1 (en) 1987-12-11 1987-12-11 MOTION DETECTOR WITH AN INFRARED DETECTOR
DE3742031 1987-12-11

Publications (2)

Publication Number Publication Date
EP0319876A2 true EP0319876A2 (en) 1989-06-14
EP0319876A3 EP0319876A3 (en) 1990-05-30

Family

ID=6342380

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88120222A Withdrawn EP0319876A3 (en) 1987-12-11 1988-12-03 Motion alarm with an infrared detector

Country Status (4)

Country Link
US (1) US4893014A (en)
EP (1) EP0319876A3 (en)
DE (1) DE3742031A1 (en)
NO (1) NO173476C (en)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH676642A5 (en) * 1988-09-22 1991-02-15 Cerberus Ag
DE4006631C2 (en) * 1990-03-03 1994-11-24 Berker Geb Protective cover for a passive infrared motion detector with the possibility of setting a monitoring area
DE4100536A1 (en) * 1991-01-10 1992-07-16 Hochkoepper Paul Gmbh IR movement detector with variable field of view for monitoring - has lens foil in front wall of housing focussing radiation onto two sensors on rear wall
DE4445196A1 (en) * 1994-12-17 1996-06-20 Abb Patent Gmbh Movement indicator with radiation sensor determining radiation emanating from region
IL112396A (en) * 1995-01-19 1999-05-09 Holo Or Ltd Intrusion detector
DE29503531U1 (en) * 1995-03-03 1995-05-18 Rev Ritter Gmbh Motion detector with infrared sensor
DE19532680A1 (en) * 1995-09-05 1997-03-06 Telefunken Microelectron Optical system
DE19822053B4 (en) * 1998-05-16 2007-01-18 Insta Elektro Gmbh Fresnel lens arrangement for passive infrared motion detectors
US7297953B2 (en) * 2005-04-13 2007-11-20 Robert Bosch Gmbh Infrared detecting apparatus
US20070030148A1 (en) * 2005-08-04 2007-02-08 Gekkotek, Llc Motion-activated switch finder
GB2509884B (en) 2011-11-16 2018-10-17 Tyco Fire & Security Gmbh Motion detection systems and methodologies

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0025188A1 (en) * 1979-09-10 1981-03-18 Cerberus Ag Optical arrangement for a photodetector
EP0094658A1 (en) * 1982-05-17 1983-11-23 Cerberus Ag Passive infrared intrusion detector
DE3235250A1 (en) * 1982-09-23 1984-03-29 Heimann Gmbh, 6200 Wiesbaden Facetted optical system for detecting radiation from a large solid angle, in particular for motion detectors
EP0113468A2 (en) * 1983-01-05 1984-07-18 Marcel Dipl.-Ing. ETH Züblin Optical device for deflecting optical rays
US4625115A (en) * 1984-12-11 1986-11-25 American District Telegraph Company Ceiling mountable passive infrared intrusion detection system

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4772797A (en) * 1986-09-08 1988-09-20 Cerberus Ag Ceiling mounted passive infrared intrusion detector with prismatic window
US4790654A (en) * 1987-07-17 1988-12-13 Trw Inc. Spectral filter

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0025188A1 (en) * 1979-09-10 1981-03-18 Cerberus Ag Optical arrangement for a photodetector
EP0094658A1 (en) * 1982-05-17 1983-11-23 Cerberus Ag Passive infrared intrusion detector
DE3235250A1 (en) * 1982-09-23 1984-03-29 Heimann Gmbh, 6200 Wiesbaden Facetted optical system for detecting radiation from a large solid angle, in particular for motion detectors
EP0113468A2 (en) * 1983-01-05 1984-07-18 Marcel Dipl.-Ing. ETH Züblin Optical device for deflecting optical rays
US4625115A (en) * 1984-12-11 1986-11-25 American District Telegraph Company Ceiling mountable passive infrared intrusion detection system

Also Published As

Publication number Publication date
NO173476B (en) 1993-09-06
EP0319876A3 (en) 1990-05-30
NO173476C (en) 1993-12-15
DE3742031A1 (en) 1989-06-22
NO885487L (en) 1989-06-12
US4893014A (en) 1990-01-09
NO885487D0 (en) 1988-12-09

Similar Documents

Publication Publication Date Title
DE2904654A1 (en) OPTICAL ARRANGEMENT FOR A PASSIVE INFRARED MOTION DETECTOR
DE2653110C3 (en) Infrared Radiation Intrusion Detector
EP0652422B1 (en) Device for receiving light rays
DE3129753A1 (en) PASSIVE INFRARED ROOM PROTECTION DEVICE
EP0218055B1 (en) Infrared movement detector
EP0565090A1 (en) Procedure and device to measure the dimensions of an object
DE2851444A1 (en) LIGHT GRID
EP0191155B1 (en) Infrared intrusion detector
EP0065159B1 (en) Motion detector for space supervision
DE2537380A1 (en) BURGLAR ALARM
EP3518000A1 (en) Optoelectronic sensor and method for detecting objects
EP0080114B2 (en) Radiation detector with sensor elements
CH676642A5 (en)
EP2453252A1 (en) Energy efficient 3D sensor
EP0319876A2 (en) Motion alarm with an infrared detector
EP0020917A1 (en) Optical arrangement for a passive infrared movement detector
EP0821330B1 (en) Smoke detector
EP0025188B1 (en) Optical arrangement for a photodetector
DE202005010358U1 (en) Optolectronic light barrier for security applications has frame with pairs of lamps separated by pairs of light sensors and has opposed frame with 45 degree mirrors set in two staggered rows
DE3137835C2 (en)
EP4118405B1 (en) Infrared motion detector
EP0050750B1 (en) Infrared intrusion detector
DE2942181A1 (en) OPTICAL-ELECTRONIC ARRANGEMENT FOR A THERMOGRAPHIC IMAGE AND TRACKER
DE19540299A1 (en) Infrared movement warning device with two switchable detectors
EP2916143B1 (en) Device and method for recording objects in a surveillance area

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH DE ES FR GB IT LI NL SE

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH DE ES FR GB IT LI NL SE

17P Request for examination filed

Effective date: 19900703

17Q First examination report despatched

Effective date: 19930210

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19940701