LAMP AND SYSTEM WITH WALL-TYPE RADIATION FIELDS FOR PREVENTING OR MINIMISING THE SPREAD OF PATHOGENS IN INDOOR AIR
20230218791 · 2023-07-13
Inventors
Cpc classification
A61L2202/14
HUMAN NECESSITIES
A61L2/24
HUMAN NECESSITIES
H05B47/115
ELECTRICITY
Y02B20/40
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
A61L2209/111
HUMAN NECESSITIES
A61L2202/11
HUMAN NECESSITIES
International classification
Abstract
The invention is directed to a system for preventing or minimizing the spread of viruses, and to the prevention or minimization of the spread of viruses in indoor air, including one or more radiation sources (10) in a room which divide the room into smaller segments using UV-C light walls, a sensor system for detecting a movement or a presence of one or more persons (P) in the room, and a controller (16) that is designed to at least partially switch the one or more radiation sources (10) on or off as a function of at least the presence of the person (P).
According to the invention, the one or more radiation sources (10) are designed to generate a wall-type radiation field (10b) that acts as a UV-C wall, so that the room or rooms is/are divided into smaller room segments, which prevents or minimizes the spread of viruses due to the fact that the viruses are deactivated by the UV-C light, and the controller (16) is designed to at least partially switch off the radiation source (10) in question if the movement data detected by the sensor system indicate a likelihood that one of the persons (P) would like to pass through the radiation field (10b) in question.
Claims
1. A lamp for forming a barrier for pathogens in indoor air, comprising a plurality of UV-C radiation-emitting illuminants (51, 51a, 51b; 151.1, 151.2) and a plurality of optical elements (54, 54a, 54b; 154 U, 154 O) for collimating radiation, which in each case are associated with an illuminant (51, 51a, 51b; 151.1, 151.2), the plurality of illuminants (51, 51a, 51b; 151.1, 151.2) and these associated optical elements (54, 54a, 54b; 154 U, 154 O) forming at least one group, and the radiation directions R of the collimated radiation that is emitted by the illuminants (51, 51a, 51b; 151.1, 151.2) within a group being situated in a shared surface, in particular a plane.
2. The lamp according to claim 1, characterized in that the radiation directions R of the collimated radiation that is emitted by the illuminants (51, 51a, 51b) within a group are parallel to one another, or the radiation directions R of assemblies within a group are parallel to one another, wherein an assembly includes multiple illuminants (151.1, 151.2) of a group together with their associated optical elements (154 U, 154 O).
3. The lamp according to claim 1 or 2, characterized in that each group includes multiple assemblies.
4. The lamp according to claim 1, characterized in that the optical device (54, 55, 154) includes a screening device (55) for screening out divergent radiation components.
5. The lamp according to one of claims 1 through 3, characterized in that the illuminants are LEDs (154.1, 154.2).
6. The lamp according to claim 4, characterized in that each illuminant (154.1, 154.2) is made up of at least two LED chips (176.1, 176.2) that are arranged in succession in the longitudinal direction of the lamp (50).
7. The lamp according to one of claims 1 through 5, characterized in that the illuminants (51, 51a, 51b) of at least one group are divided into subgroups (57a, 57b, 57c; 157a, 157b, 157c), and the illuminants (51, 51a, 51b) of these subgroups (57a, 57b, 57c; 157a, 157b, 157c) may be jointly switched on and off, but independently of the illuminants (51, 51a, 51b) of other subgroups (57a, 57b, 57c; 157a, 157b, 157c).
8. The lamp according to claim 7, characterized in that each subgroup corresponds to an assembly.
9. The lamp according to one of claims 1 through 6, characterized in that the lamp includes two groups that are situated symmetrically with respect to a center plane of the lamp.
10. The lamp according to one of claims 1 through 7, characterized in that the lamp (10, 50, 150) is designed as a light strip for ceiling or wall mounting.
11. The lamp according to one of claims 1 through 8, characterized in that the pathogen-deactivating UV-C radiation that is bundled to form a UV-C wall is far UV-C radiation having a wavelength in the range of 200-222 nm, in particular 207-222 nm.
12. The lamp according to one of claims 1 through 9, characterized in that the pathogen-deactivating UV-C radiation that is bundled to form a UV-C wall is UV-C radiation having a wavelength in the range of 223-280 nm, in particular having a wavelength greater than 242 nm.
13. A system for preventing or minimizing the spread of pathogens in indoor air, including one or more radiation sources (10) in the form of one or more lamps (10, 50, 150) according to one of claims 1 through 10, characterized in that the system comprises a sensor system (14) for detecting a penetration of one or more persons (P) or objects into a safety zone that is formed adjacent to the radiation field, and a controller (16) that is designed to at least partially switch the one or more radiation sources (10, 50, 150) on or off as a function of at least the presence of the person(s) (P) and/or objects, the controller (16) being designed to at least partially switch off the radiation source (10, 50, 150) in question when the sensor system (14) detects a penetration.
14. The system according to claim 11, characterized by freely movable stands (20) for holding one or more radiation sources (10, 50, 150).
15. The system according to one of claim 11 or 12, characterized in that the one or more radiation sources (10, 50, 150) are designed for arrangement along boundaries of room segments (12), the controller (16) being designed to activate the radiation sources (10, 50, 150) in question when one or more persons (P) are present in the room segment (12) in question, and to deactivate at least one of the radiation sources (10, 50, 150) when a person (P) enters or leaves the room segment (12).
16. The system according to one of claim 13 or 15, characterized in that further radiation sources (18) having a pathogen-deactivating or disinfecting effect are situated within the room segments (12), and the controller (16) is designed to activate the further radiation sources (18) when no person (P) is present in the room segment (12).
17. The system according to one of claims 13 through 16, characterized in that the sensor system includes a 3D camera or TOF camera and/or one or more CCD cameras.
18. The system according to one of claims 13 through 17, characterized in that the sensor system (14) includes at least one light source, and is configured to detect changes in the reflected portion of the light that is emitted by the light source and reflected from objects (62) in the surroundings.
19. The system according to one of claims 13 through 18, characterized in that the sensor system (14) is configured to determine a penetration into the safety zone with spatial resolution, and the controller (16) is configured to switch off at least one illuminant (51, 51a, 51b) based on the location of the penetration.
20. A method for preventing or minimizing the spread of viruses in indoor air, using one or more radiation sources (10) in a room, characterized in that the method includes generating at least one radiation field (10b), using at least one lamp according to one of claims 1 through 12, and detecting a movement or a presence of one or more persons (P) or objects (62) in the room, and automatically switching at least a portion of the illuminants of one or more radiation sources (10) on or off as a function of at least the presence of the person (P) or object (62).
Description
[0046] In the drawings:
[0047]
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[0050]
[0051]
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[0066] Before discussion of one specific embodiment for explaining a lamp according to the invention for achieving, as a result of the invention, the protection of persons in a room from infection with pathogens that are transmittable via air, the system that is set up using the lamp according to the invention is first explained.
[0067]
[0068] A grid-like arrangement of radiation sources 10 is mounted on the ceiling of the room. Each of the radiation sources 10 is a light strip that includes one or more UV-C radiators 10a (
[0069] For generating a wall-like radiation field 10b, radiation may be bundled or collimated to form parallel beams, optically or by use of slit diaphragms, as explained in greater detail below with reference to
[0070] The room segments 12 are each delimited from one another by UV-C walls 10b. In the exemplary embodiment illustrated in
[0071] Even though such special cases are not illustrated in
[0072] Structures such as half-height walls, room dividers, or the like may be continued up to the ceiling or expanded via a UV-C wall 10b. In this case, the radiation sources 10 could also be mounted on the top side of the structure in question, and could radiate upwardly toward the ceiling.
[0073] In addition, sensors 14a (
[0074] A central controller 16 is designed, via suitable software, to switch the one or more radiation sources 10, or at least portions of an individual radiation source 10, on or off as a function of at least the presence of the person P, as described in greater detail below. For this purpose, the controller 16 communicates with the radiation sources 10 via signal lines or wirelessly, for example via WLAN.
[0075] The controller 16 evaluates the position data and movement data of the persons P and computes likelihoods for various paths or movements of the persons P. When a person P is sitting quietly at his/her workstation and at a sufficient distance from all UV-C walls 10b, it is unlikely that within the next fraction of a second he/she will pass through one of the UV-C walls 10b. However, if the person is walking quickly through a corridor that is divided into room segments 12 by multiple UV-C walls 10b, the point in time of passing through the next UV-C wall 10b is easily predictable. Because of the health risks, the radiation sources 10 are switched off even for a small likelihood; due to the lower risks, the threshold value for the use of far UV-C radiation may be set to a higher value than for longer-wave types of UV radiation.
[0076] If a sufficient likelihood for passing through the UV-C wall 10b has been established based on the movement data detected by the sensor system 14, the controller 16 switches off the radiation source 10 in question, or at least portions thereof. For switching off only a portion, a totality of illuminants that are provided as radiators in the radiation source 10 are divided into groups and optionally subgroups, as described below in the detailed explanation of a lamp as a radiation source 10. In contrast, if an illuminant that extends longitudinally in the radiation source 10 is used, it is only possible to switch off the entire illuminant. Alternatively, switchable screens may be provided, with which certain areas may be shaded.
[0077] The persons P may therefore move freely in the room. If the person P passes through a boundary surface between two room segments 12, the controller 16 switches off the UV-C wall 10b that forms this boundary surface, and switches the UV-C wall 10b back on when the person is completely in the second room segment 12.
[0078] While one or more persons P are present in the room segment in question 12, the particular radiation sources 10 generally remain active, so that viruses and bacteria in droplets or aerosols are killed upon leaving the room segment 12. Persons P who are present in different room segments 12 are thus shielded from one another by means of the radiation field that forms the barrier. Since the radiation sources 10 remain active while persons P are present in the room segments 12, absorber strips that absorb the incident UV-C light from the radiation sources 10 may be affixed to the floor in order to avoid damage to health due to scattered light.
[0079] The radiation source 10 associated with the corresponding UV-C wall 10b is deactivated only when a person P wishes to enter or leave the room segment 12 through a UV-C wall 10b.
[0080] As an alternative or in addition to the above-described detection of movements of a person in the room, it is preferably provided that the penetration of a person or an object into a safety zone provided directly adjacent to the radiation field is detected by the sensor system. Such a procedure is explained in greater detail below with reference to
[0081] The transport of the pathogens takes place via the air. Typical air movement speeds in indoor spaces do not exceed 0.1 m/s. In order to reliably inactivate pathogens, they must absorb a minimum quantity of energy via the irradiation. For the at least 0.6 m/cm.sup.2 stated above, the retention time of the viruses or bacteria in the radiation field having the preferred thickness d is sufficiently long to achieve the inactivation. In contrast, in the prior art significantly larger volumes, i.e., also thicknesses of the radiation field, are necessary, since for the lower irradiation intensities typically achieved there, longer retention times are required for killing the viruses or bacteria.
[0082] Further radiation sources 18 having a virus-deactivating or disinfecting effect are centrally mounted on the ceiling in the room segments 12.
[0083] The controller 16 is designed to activate the further radiation sources 18 for a predefined time interval if no person is present in the room segment 12. These radiation sources 18 are also switched off when a person P enters the room segment 12 in question. In order to indicate to the person P whether the disinfection of the room segment in question 12 is concluded, a light-emitting diode or a “traffic light” system may be provided. Further embodiments of the invention are conceivable in which the sensor system 14 includes sensors that are integrated into the radiation sources 18. The radiation sources 18 may be integrated into ceiling panels, lamps, or ventilation louvers, or integrated into a housing with other devices, for example smoke detectors.
[0084]
[0085] In the work state illustrated in
[0086] In the disinfection state illustrated in
[0087] In the rest state illustrated in
[0088]
[0089] As described above, the controller 16 implements a method for preventing or minimizing the spread of viruses in indoor air, using one or more radiation sources 10 in a room. The method includes detecting a movement or a presence of one or more persons P in the room, and automatically switching one or more radiation sources 10 on or off as a function of at least the presence of the person P.
[0090] According to the method, the radiation source 10 in question is switched off when the movement data detected by the sensor system 14 indicate that it is likely that one of the persons P would like to pass through the radiation field 10b in question, or that a person or an object has penetrated into the safety zone.
[0091]
[0092] In the exemplary embodiment illustrated in
[0093] For forming the above-described system, lamps 50 that correspond to the embodiments illustrated in
[0094] The lamp 50 illustrated in
[0095] The illuminant 51 emits germicidal UV-C radiation, which is collimated by a reflector 54. The reflector 54 is one example of an optical element via which radiation that is emitted by the illuminant 51 may be collimated. Other optical elements, for example appropriately designed lenses, are likewise conceivable. The selection and development of the optical element used for collimating the emitted radiation may take place based, for example, on economic or manufacturing aspects or the efficiency.
[0096] The radiation that is reflected at the inner side of the rotationally symmetrical reflector 54 is referred to as collimated radiation. This collimated portion of the radiation that is emitted by the illuminant 51 leaves the exit opening 53; due to the collimation, the collimated radiation leaves the exit opening 53 within an imaginary cylinder, having the diameter d, in the direction of the z axis. The geometry of the reflector 54 is selected in such a way that for typical room heights or room dimensions, which may be estimated using a maximum length L equal to 5 m, the diameter d of the collimated radiation is always less than 8 cm, preferably less than 5 cm. It should be noted that these data are strictly preferred values. To allow such a small extension in the transverse direction with respect to the radiation direction, it is preferred to use LEDs as the illuminant 51. The irradiation intensity achieved within the diameter d is greater than 0.6 mW/cm.sup.2, which ensures that pathogens penetrating into the radiation field of the barrier are reliably killed. Unlike systems known from the prior art which irradiate a large air volume in each case, the pathogens may already be inactivated over the small distance due to the thickness of the radiation field, which corresponds to the diameter d of the collimated radiation.
[0097] The longitudinal axis of the lamp 50 is perpendicular to the plane of the drawing. The arrangement of the illuminant 51 and of the reflector 54, illustrated in cross section, is repeated along the longitudinal axis of the lamp 50, with the plurality of illuminants 51 and their associated reflectors 54 situated in the lamp 50 being arranged along a line, preferably a straight line. In the embodiment illustrated in
[0098] As will be explained in greater detail below, the neighboring reflectors 54 are arranged along this line in such a way that the radiation collimated in each case within the diameter by the neighboring reflectors 54 is directly adjacent and overlaps the radiation in the areas A, and the totality of the collimated radiation of the illuminants 51 thus generates the wall-like radiation field 10b as a barrier for viruses. The maximum extension of this wall-like radiation field 10b in a direction perpendicular to the longitudinal extension of the lamp 50 and to the radiation direction, i.e., the extension in the direction of the y axis, is bounded by two imaginary planes E1 and E2. The distance between these two planes E1 and E2 thus corresponds to the diameter d of the imaginary cylinder.
[0099] The illuminants 51 and the reflectors 54 are coordinated with one another in such a way that the intensity of the collimated radiation is sufficient to kill pathogens, and as stated above, in particular is greater than 0.6 mW/cm.sup.2. In contrast, outside the UV wall 10b thus formed, radiation is present only with a noncritical intensity. This radiation results from the uncollimated portion of the radiation that is emitted by the illuminant 51, i.e., the portion that exits from the reflector 54 without reflection. In
[0100] For enhancing safety, a screening device 55 is preferably situated in the area of the exit opening 53 of the lamp 50. The screening device 55 itself may form the exit opening 53, or it may be situated inside or also outside the housing 52 of the lamp 50. The operating principle of the screening device 55 is explained in greater detail below with reference to
[0101]
[0102]
[0103] The screening device 55 may be provided either individually for each reflector 54, and for example cover the opening of the reflector 54, or may be provided as a shared screening device for the totality of the reflectors 54.
[0104] In addition, it is to be noted that for the detailed explanation of the lamp 50, it is assumed that a plurality of individual illuminants 51 jointly emit the radiation that ultimately forms the UV wall. However, an illuminant that extends in the longitudinal direction may also be used for generating the radiation.
[0105]
[0106] In the illustrated exemplary embodiment, it is assumed that all reflectors 54 that are provided in a lamp 50 have identical geometries. The collimated radiation that is thus emitted in each case by an illuminant 51 with the aid of its associated reflector 54 is thus the same with regard to its radiation geometry. In principle, it is also conceivable to use different geometries for neighboring reflectors 54. The distance between the particular axes of symmetry when rotationally symmetrical reflectors are used is then to be adapted in each case so that the imaginary cylinders that envelop the collimated radiation intersect. In order for an overlap of the collimated radiation to reach neighboring reflectors, the neighboring reflectors may also be arranged in such a way that their radiation directions enclose a small angle relative to one another. In particular the first, third, fifth, etc., reflectors are situated so that their radiation directions are in parallel to one another, but the radiation directions of the second, fourth, sixth, etc., reflectors enclose an angle, with their radiation directions once again being in parallel to one another.
[0107] As indicated above, for operating the lamp 50 according to the invention or the overall system, the emitted UV radiation must be reliably prevented from striking persons who could thus be harmed. In addition to the prediction of movements of persons, or detections of the location at which persons are present, explained above in conjunction with the system, the direct penetration into a safety zone, defined as adjacent to the radiation field, i.e., neighboring the planes E1 and E2, may be detected.
[0108] In the illustrated exemplary embodiment, reflections that result when radiation that is emitted by a so-called line laser 60 strikes a surface are detected by means of sensors 14a. In the illustrated exemplary embodiment it is assumed that persons may be present on both sides of the UV wall 10b, as is typical in a restaurant. Therefore, a line laser 60 and an associated camera as a sensor 14a for detecting the reflections of the laser beam are provided on both sides of the UV wall 10b. To the left of the UV wall 10b it is apparent that the emitted laser radiation of the line laser 60 situated on the left falls, for example, on the floor or some other essentially unchangeable device objects. This reflection is detected by the sensor 14a.
[0109] In contrast, on the right side of the UV wall 10b it is shown that an object 62, which may be, for example, a finger of a person or an object that is moved by the person, approaches the UV wall 10b and thus comes into an area, in that it reflects a portion of the laser light that is radiated by the line laser 60. Up to the time of penetration into the plane of the laser light that is emitted by the line laser 60, here as well the light has been reflected solely from the floor. In contrast, the reflection changes immediately upon penetration by the object 62, which is detected by the sensor 14a. Based on the change, the penetration of an object into the safety zone may be deduced. The safety zone is the space from the UV wall 10b or the adjoining plane E2 up to and including the radiation that is emitted parallel to the plane E2 by the line laser 60 situated on the side of the plane E2.
[0110] A safety zone is likewise formed on the side of the other plane E1. The formation of a second safety zone may be dispensed with if the lamp is mounted close to a wall and parallel thereto, so that penetration into the area of the UV wall 10b is impossible from this side.
[0111] When the lamp 50 generates multiple radiation fields 10b′ through 10b′″ situated in parallel, the safety zones are to be provided only adjoining the respective outermost radiation field. The increasingly larger distances on the end-face side due to the multiple radiation fields 10b′ through 10b′″ are then to be safeguarded using separate protective measures. These may correspond to the above-described safety devices situated in parallel to the radiation fields. If the extension of the lamp extends between two walls or other structural objects that shield UV light, safeguarding the end-face sides may also be dispensed with.
[0112] The above statements in each case assume that the light wall may be built using an individual illuminant and an assigned reflector, with multiple such units in a consecutive series. The shown arrangement positions the illuminant in the center of the reflector. However, such a design is problematic with regard to the achievable irradiation intensities. In particular, in this simple arrangement the extension of the illuminant, i.e., at least the radiating surface of an LED, for example, also ensures that the delimitation between the illuminated surface within the thickness d and its neighboring area A is very indistinct. However, it is desirable for the area that is active for killing the pathogens to be delimited from its surroundings as sharply as possible. Therefore, an arrangement as described below is preferred, in which multiple illuminant elements and their associated optical devices (reflector partial surfaces of a reflector unit) are combined to form a UV radiator unit. The structure of the overall wall-like radiation field is obtained by situating multiple of these UV radiator units in succession. In other respects, the above statements also apply to a system that generates the wall-like radiation field using the arrangement described below.
[0113] Firstly,
[0114] It is clearly apparent in
[0115]
[0116] It is also apparent in
[0117]
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[0120] The above statements in each case relate to a reflector surface 154 U, with a plurality of reflector surfaces and their associated units, made up at least of the illuminant element 151.i and the hemispheric lens 175 situated in front of same, cooperating to form a UV radiator unit.
[0121] The beam path in
[0122] Each reflector surface extends 60 mm in the Y direction, so that the overall width of the reflector unit in the Y direction is 120 mm. These dimensions (120 mm times 210 mm) correspond to the illuminated surface at a distance of 2500 mm from the reflector unit 154 (reference surface). This distance is measured starting from the rear-side, shared mounting plane of the overall reflector unit. Since the surface of the reflector unit 154 and the irradiated surface are the same size, the extension of the wall-like radiation field may be enlarged by situating multiple UV radiator units in a consecutive series, without at the same time increasing their thickness.
[0123]
[0124]
[0125] Alternatively, as described above, an inclination of the reflector surfaces or illuminant elements could also be provided. However, on the one hand this results in more complex manufacture of the reflector unit 154, and on the other hand, the illuminant elements then can no longer be situated in a shared plane.
[0126] A consideration of the illumination intensities that result when all six reflector surfaces reflect light from six associated illuminant elements 151.i results in the distribution of the illumination intensity as illustrated in
[0127] It should be noted that the above statements assume that two LED chips jointly form an illuminant element. However, it is also conceivable for more than two LED chips to form an illuminant element if this plurality, for example three, are likewise arranged in a row.
[0128] In such a case, the number of reflector surfaces could even be reduced, since each reflector surface in this case would be illuminated by the light from three LED chips. In consideration of the losses that occur at the illuminated surface, it is crucial that a sufficiently high irradiation intensity is achieved. For a given radiation power of the LED chips, this results in the number of chips required for irradiating a certain surface. It should be noted that the irradiation intensity that occurs at the illuminated surface is merely a measure for describing the power density in the wall-like radiation field. Ultimately, the area between the lamp and the irradiated surface that is illuminated by light is crucial for killing pathogens.
[0129] The functioning of the safety devices discussed above is now explained with reference to the illustration in
[0130] In the lamp 50 illustrated as an example, a total of fourteen illuminants 51 are arranged along a straight line, and an optical element in the form of a reflector 54 (illustrated here without a reference numeral) is associated with each of these illuminants 51, which for the sake of better clarity are not separately illustrated in
[0131] As an alternative to a lamp 50 as illustrated, which includes only a single group of illuminants, multiple groups of illuminants may also be provided. Within a group, the illuminants and their associated reflectors are then likewise once again arranged in such a way that their radiation directions are parallel to one another and are situated in a plane, or as stated as an alternative above, lie in a surface. The planes (or surfaces) of various groups may be situated in parallel and spaced apart from one another, or they may enclose an angle.
[0132] For the group of illuminants and their associated optical elements of the lamp 50, it is shown that the group is divided into three subgroups 57a, 57b, and 57c. Each of these subgroups 57a, 57b, and 57c contains a plurality of illuminants and their associated optical elements. The subgroups 57a, 57b, and 57c may be individually controlled, i.e., switched on and off, by the controller 60.
[0133] If an object 62, upon penetration into the plane illuminated by the line laser 60, is now detected based on the signals recorded by the sensor 14a, the position of the object 62 is determined from the signals transmitted from the sensor 14a to the controller 16 or to the information processing device of the sensor system 14 integrated therein.
[0134] It should be noted that only one line laser 60 and one sensor 14a are shown in
[0135] In contrast, when only one arrangement is used, the position of the object 62 may be determined at least in one direction (x axis). The detected position is evaluated in the controller 16, and the subgroup 57a, 57b, or 57c whose emitted, collimated radiation would strike the object 62 is switched off. In the illustrated exemplary embodiment, this is the middle group 57b. It should be noted that the term “position” is understood to mean not only a midpoint of a detected object 62, but also its extension. Thus, if a detected object 62 is not completely in the area of the light that is radiated by a subgroup 57a, 57b, or 57c, not just one subgroup is switched off, due to the position detection, including the extension of the object 62.
[0136] On the other hand, if the position coordinates are known for two directions (x axis, y axis), a second lamp 150 whose design is basically comparable to that of the lamp 50, and whose radiation directions with the radiation directions of the lamp 50 enclose an angle not equal to 0° or 180°, may be used. The radiation directions of the lamps 50 and 150 are preferably perpendicular to one another. The radiation directions of both lamps 50 and 150 are preferably situated in the same plane, so that the sensor system 14, including the line laser 60 and the sensors 14a, may be jointly used. If the position of the object 62 is determined in two dimensions with the aid of the sensor system 14, not only the subgroup 57b of the lamp 50 that emits UV light in the area of the detected object 62, but also the corresponding subgroup 157b of the second lamp 150, may be switched off. Thus, as is directly apparent from the drawing, only a relatively small area is not illuminated with UV-C radiation so that fairly large gaps in the barrier may be prevented.
[0137] In the example in
[0138] The above statements with regard to
[0139] If multiple groups are situated symmetrically with respect to the plane of symmetry S, the subdivision of the illuminants is preferably identical for both subgroups. No safety device is then necessary between the symmetrically situated groups. It is sufficient to provide such a safety device on the respective outwardly directed sides. The mutually corresponding subgroups or assemblies of the two groups are jointly controlled. Corresponding subgroups or assemblies are defined by identical positions with respect to the x axis, and identical sizes.
[0140]
[0141] In further embodiments of the invention not illustrated, the stands may hold light strips or radiation sources that radiate vertically downwardly. In addition, it is conceivable for the light strips or radiation sources to be situated on the floor and to radiate toward the ceiling.