Abstract: The invention concerns an arrangement for electronically detecting an X-ray image, the arrangement comprising a converter (4), in particular a scintillation foil (3). A visible image is generated on the display surface (5) of the scintillation foil (3) by X-rays. At least two mirrors (7) are provided which produce images of segments of the display surface (5). In addition, electronic camera systems (8) are provided for converting the image segments reflected by the mirror (7) into electrical signals. The beam path (9) between the camera systems (8) and mirrors (7) is approximately parallel to the display surface (5).

Abstract: An optical arrangement and a process for transmitting and converting X-ray images generated on a two-dimensional primary image array (21a) with light emission within the visible spectrum contains a plurality of optical systems (17) for reduced imaging of a sectional image (19) corresponding to an individual segment (19) of the primary image (20). The imaging is effected through an optical image guide (22). At least two image guides (22) are joined to combine sectional images into first images (19b). Each first image then contains at least two segments (19, 19a) of the primary image (20). The image guides (22) on the output side are connected to the input of a converter (28) by which the light signals are converted into processable electrical signals.

Abstract: 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 compared in a correlator with reference or set signals stored in a read-only memory and/or with the actual signals obtained from a second sensor element monitoring the near region. The correlator delivers an output signal which corresponds to the correlation of both signals which are compared with one another. An alarm signal is triggered when the correlation exceeds a predetermined value, for instance 0.7, and the amplitude has reached a predetermined threshold. The infrared detector affords high security against giving of false alarms and a high detection probability, even in the presence of signals possessing a great amount of noise, but also delivers an alarm signal in the event the detector is attempted to be sabotaged, for instance by covering the inlet optical system.

Abstract: In a light barrier, especially for outside application and long distances monitored, insensitivity to interfering light and scattering through fumes or fog and an increased range and sensitivity to objects passing through the light barrier are achieved by subdividing radiation from a source into two radiation branches which are offset relative to each other and differently polarized, e.g., by means of a polarization filter divided into two parts, with different linear or oppositely circular polarization of the filter part surfaces. By means of an analogously subdivided polarization filter, the radiation of each of the two radiation branches is focused on a different individual sensor element. The two sensor elements are connected in a differential circuit which triggers an alarm signal in response to signals arriving from both radiation branches in short succession but does not trigger an alarm signal if both sensor elements are equally irradiated.

Abstract: The circuit arrangement generating at least one noise-level warning threshold monitors the noise-level of detectors in an alarm system. The noise-level warning threshold assumes a fixed relation to the operating or working point level of the signal transmitted by the detector of the alarm system while taking into account shifts in the level of the operating or working point. An alarm storage or buffer disposed in the detector is set without transmitting an alarm signal when the noise-level warning threshold has been exceeded. The noise-level is monitored during normal operation and gives sufficiently early warning of a tendency to generate false alarms.

Abstract: The optical arrangement for an infrared intrusion detector containing a plurality of separate radiation receiving regions or fields of view is provided with a first focussing optic or optical system, for instance a Fresnel lense which receives with its entire surface or area the infrared radiation which arrives from all of the receiving regions and delivers such received radiation to a multiplicity of further focussing means, for instance to individual reflectors. These reflectors are correlated in each instance to one of the receiving regions or fields of view and focus the radiation arriving from such receiving region upon a sensor element. In this way there is attained the beneficial result of optimum utilization of the infrared radiation which is available and the sensitivity of the infrared intrusion detector can be increased. The dimensions of the optical arrangement and the intrusion detector can be maintained small and relatively imperceptible.

Abstract: An infrared intrusion detector wherein a plurality of separate radiation receiving regions or fields of view are focused by a single focusing optic, for instance a reflector or a Fresnel lens upon a single sensor element through an elongate or lengthwise extending radiation collecting element. The radiation collecting element can be constituted by an internally metal coated tube or a transparent body having a reflecting surface layer or coating, wherein the reflection coating is interrupted by radiation inlet openings. The infrared radiation which is focused by the focusing optic enters through such openings into the interior of the radiation collecting element and arrives, after having been reflected a number of times, at the sensor element which is mounted at an end side thereof.