Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
  • G01S7/481—Constructional features, e.g. arrangements of optical elements
  • G01S7/4818—Constructional features, e.g. arrangements of optical elements using optical fibres
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
  • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
  • G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
  • G01S17/04—Systems determining the presence of a target
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
  • G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
  • G01S7/48—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S17/00
  • G01S7/481—Constructional features, e.g. arrangements of optical elements
  • G01S7/4811—Constructional features, e.g. arrangements of optical elements common to transmitter and receiver

Definitions

• the invention has for its object to improve distance measuring systems.
• the invention relates to a sensor device with a distance sensor, which consists of a transmitting device with at least one transmitter with a light source and a receiving device with at least one receiver and an electronic unit, wherein the electronic unit is adapted to emit light by means of the transmitter and a distance, the light emitted by the transmitter from a reflection surface of an object in a surveillance area travels to the respective receiver to determine.
• the distance measurement may e.g. by an evaluation of a transit time of the light and / or a phase of an oscillation modulated onto the light.
• Such sensors are also referred to as "time of light” sensors (TOF sensors).
• a reflection may comprise a reflection and / or a reflection by total reflection.
• a multiple total reflection of the light signal takes place on the delimiting outer surface of the glass fiber.
• the procedure of the light guide on an angled path is particularly advantageous if several separate areas are to be monitored, wherein the receiving device without optical fiber means can not see all separate areas and / or the transmitting device without optical fiber means can not irradiate all separate monitoring areas with light.
• the light guide means both a light return and a light irradiation of an object can then take place from areas which are optically completely separated directly from one another.
• the procedure according to the invention has the advantage that the distance sensor does not have to be at the point at which measurements are to be carried out. This also allows comparatively small-scale and poorly accessible areas to be monitored. For example, such systems can be used in vending machines. In such vending machines, the number of products in separate storage slots can be detected via a distance measurement.
• the light reflected back from the object can be evaluated for the color.
• Light can be emitted at different frequencies, that is to say colors from a transmission device, in order to obtain color information of an object in the surveillance area.
• the object is irradiated with light of a color and, in addition, the reflected light is detected. The same thing happens with another color.
• the back-reflected light intensity it can be deduced to which color the object is to be assigned. This can be used to identify a product. It is also conceivable that - A -
• Evaluate receiver device The irradiation of the object with different colors simultaneously or sequentially need not take place in the visible range. It is also possible to use invisible light.
• the light guide means regularly transmit the light in the volume of the light guide.
• the light guide means can be used glass fiber transmission or fiberglass optical fiber.
• the distance sensor comprises only one receiver and several transmitters or only one transmitter and a plurality of receivers.
• control unit which allows independent control of transmitters and receivers.
• a clear assignment between receiver and transmitter can be created. If e.g. It is known which light source has emitted light, an unambiguous assignment to the monitoring object can be created, even if all optical fiber means, which transmit light to a receiving device, are guided to only one receiver.
• the optical waveguide means are designed such that one and the same optical waveguide element emits light from the transmitting device into the monitoring area and from the monitoring area to the Receiving device transmits.
• the cost of the design of the optical fiber means can be reduced.
• a plurality of optical fibers are bundled in a bundle, e.g. combined to form a light guide.
• the light guide means are arranged such that light from the transmitting device via a light guide element at the monitoring point impinges directly on a light guide element that transports light back to the receiving device. It is also conceivable that the light is guided indirectly to a light guide, which transmits the light to the receiving device, e.g. over a reflector.
• light guide elements for transmitted and received light are guided to a head part. This can be done on the side of the distance sensor or on the side of the surveillance area.
• the head part may comprise lenses or other optical elements. In this way, a desired alignment of transmitters and receivers can be ensured.
• the header may also include electronic components.
• an electronic shutter for example, an electronic shutter, an electronic polarizer and / or an electronic switcher is provided. It is also conceivable that a transmitter and / or receiver is at least partially placed in a light guide head part.
• a header may comprise an antireflection layer, a pofilter, and / or a retardation layer.
• steering means are provided so that the alignment of transmitted and received light in one Headboard is significantly different and / or adjustable.
• fiber optics can not bend much. This means that in the case of a light guide arriving in a head element in a direction which is not the preferred direction, a comparatively large amount of space is necessary in order to change the direction of exiting light in the desired direction. Therefore, optical components may be provided in the header to ensure that light enters and / or exits in the desired direction.
• Optical units can be used to couple the light into a light guide. Likewise conceivable is the use of such systems at a light exit point of a light guide, or on a path of the light from the exit point to a monitoring object. Such optical elements can at least partially focus or expand light so that the light illuminates precisely the surveillance area to be monitored.
• optical elements e.g. More light can be introduced into an optical fiber, whereby a signal-to-noise ratio can be improved. Exact irradiation of only the area to be monitored also increases the accuracy of a measurement.
• a transition of optical fiber means in a head element is designed such that the light perceives no optical breakage.
• the head part can e.g. glued or welded to the optical fiber means or the head part with the light conductor means is made of one piece.
• the optical fiber means can be designed so that they can be removed in the desired length, in order then to be coupled to a sensor or a head part.
• coupling means are available to couple optical fiber means together.
• coupling can be accomplished only by plugging or snapping together, which further simplifies the entire process of tuning the length of the optical fiber means.
• the device is designed to take measures when the light intensity of received light or the measured distance falls below a predetermined threshold or exceeds a predetermined threshold.
• the predetermined threshold is adjustable or the device itself carries out an adaptation of a threshold value.
• Such a configuration is particularly preferred when a customer can change the length of the optical fiber means as desired. If the length of, for example, a fiber optic light guide is changed, the measuring distance for the light and thus also the damping behavior of the light source changes Light path. A threshold should be able to be adjusted to these changed circumstances.
• the system itself is capable of detecting the length of the optical fiber means and / or the parameters dependent thereon.
• the device according to the invention generates a protocol for this purpose.
• the use of the sensor device is safer and easier.
• Single-mode light guide and multi-mode light guide can be used light guide of different design.
• single-mode light guide and multi-mode light guide For example, single-mode light guide and multi-mode light guide.
• Single-mode fibers use single-mode fibers. With these there is only one possible light path. Therefore, no runtime differences occur at a given frequency, which is advantageous for fast data transmission and accurate distance measurement.
• the light is reflected at different angles, which can lead to runtime differences of individual light components.
• the length of the light guide can be calculated from this.
• a light guide, which leads light to the monitored area is coupled directly into the head part in a light guide for reflected light. In this way, the length of the Fiber optics are easily determined.
• a reference measurement is made to determine the effective length of the light guide that the sensor or object surface sees. Such a reference measurement can be made during installation of such a system or during manufacture.
• multimode light guides are more expensive, they make it easier to couple light into the light guide.
• optical fibers having a core diameter of ⁇ 50 ⁇ m, in particular ⁇ 20 ⁇ m, e.g. also used ⁇ 10 microns This results in fewer fashions in the light guide.
• the optical waveguide has a variable refractive index extending over the cross section, in particular if the refractive index becomes smaller towards the outside.
• the refractive index becomes smaller towards the outside. This is of particular interest in connection with multimode optical waveguides since, as a result of this measure, transit time differences between poorly reflected light in the optical waveguide and light, which was often reflected with a correspondingly longer path, are reduced. This is based on the principle that in the optically less dense medium light has a higher speed. If the refractive index towards the outside is smaller, light passes faster through these areas, which in particular benefits the light reflected multiple times at the outer area, which thereby runs on a longer path.
• optical fiber in particular an optical fiber
• the optical fiber is optimized for the frequency to be used. In this way, runtime differences of different modes in the light guide can be kept as small as possible.
• the end of a light guide is provided with microlenses.
• lenses e.g. Fresnel lenses or gradient index microlenses are used.
• the light source has a comparatively small radiation angle.
• Burrus diodes or diodes are used with a particular small beam angle.
• lasers or vcsel, vecsel components are also preferred.
• LEDs are relatively inexpensive as a light source, but have a large emission cone, which makes coupling into an optical fiber more difficult.
• lasers are expensive, but have parallel light, which can be easily coupled into a light guide, in particular an optical fiber.
• reference measurements can be made to pass through the optical fiber, e.g. to correct an optical fiber-induced error.
• blanks can be fastened in optical sensors, for example via soldering, in particular ironing or heat sealing, to name just two examples.
• Boards can have integrated light guide means and / or optical layers.
• the presence or absence of persons can be monitored, e.g. in a bed.
• the system according to the invention proves to be particularly advantageous when e.g. several beds are to be monitored with one sensor or more fields in a bed are to be monitored via a sensor.
• FIG. 1 shows a schematic side view of a greatly simplified part of a known from the prior art vending machine in combination with a sensor device
• FIG. 2 shows the part of a vending machine with a sensor device according to the invention which is highly schematized in FIG.
• FIG. 3 shows a schematic spatial representation of a sensor device according to the invention arranged in an elevator
• Figure 4 shows a security system for a door on the basis of a sensor device according to the invention shown schematically. Description of the embodiments:
• FIG. 1 shows the case in which it is attempted to monitor three separate product storage slots 4, 5, 6 of a vending machine 7 with a distance sensor 1 comprising a light source 2 and a receiving device 3.
• the product storage slot 5, 6 stacks 8, 9, 10 of products 11 are arranged.
• the product storage slot 5, 6 can be reached via light beams 13, 14 by means of the light source 2, the product stack 10 can not be reached through an intermediate wall 12 between the product storage slot 4 and 5.
• the receiving device can only detect reflected light 15 from the product stack 9, whereas light from the product stack 8 through an intermediate wall 16 between the product storage slot 6 and the product storage slot 5, the receiving device 3 can not reach. From the product stack 10 no light reaches the receiving device 3, since the light from the light source 2 is blocked by the intermediate wall 12.
• a sensor device 17 according to the invention according to FIG. 2 is used.
• the sensor device 17 likewise consists of a light source 2 and a receiving device 3.
• a light guide 18, 19, 20 from the light source 2 and in each case a light guide 21, 22, 23 is guided back to the receiving device 3.
• the light is passed through the light guides 18, 19, 20 of the light source 2 exactly to such an area, namely the product storage slots 4, 5, 6, which are to be monitored via.
• a monitoring light beam which is reflected back from a product stack 8, 9, 10, received by the optical fibers 21, 22, 23 and guided to the receiving device 3.
• the respective light guide 18, 19, 20 may be equipped with a light guide head 24.
• a light guide head 25 may be provided for an optimized introduction of reflected light 25 from the respective product stack 8, 9, 10 into the light guides 21, 22, 23, a light guide head 25 may be provided.
• the distance determination to the uppermost product 11 of a respective product stack 8, 9, 10 may be e.g. take place over the duration of the light from the light source 2 to the receiver 3 or by evaluating a phase of a modulated on the light originating from the light source 3 oscillation.
• a monitoring of spatially separated monitoring areas according to the product stacking slots 4, 5, 6 can be realized with only one receiving device and only one light source.
• a door opening 30 is shown, of a Sensor device 31, which includes a distance sensor 32 is monitored.
• the door opening 30 is monitored by 2 light beams 33, 34.
• the light rays originate from the sensor device 31 in that light is guided via light guides 35, 36 to a light guide head 37, 38, from which the light rays 33, 34 then emerge in the desired direction.
• the respective light guide head optionally includes an additional optics.
• a third light beam 39 can be used to monitor the distance between a door frame.
• the light is preferably guided via an optical waveguide 40 to an optical waveguide head 41 coming from the distance sensor 32 and exits in the desired direction as a light beam 39.
• the two light beams 33, 34 or light cone 33, 34 can be operated to distinguish them, for example in time multiplex or use different modulation frequencies.
• both light beams 33, 34 can be compared with each other. If both beams of light measure the same distance, it is the door, otherwise it is an object that may require a safety precaution. This can be to initiate an immediate opening of the door.
• the additional light beam 39 which, if necessary, as well as the light beams 33, 34 is operated in the multiplex or with different modulation frequency to these light beams, increased security in the monitoring of the door opening 30 can be achieved.
• the light rays measure a sudden change in distance, and above
• the distance that the light beams 33, 34 measure is different can thereby close to an object in the door opening 30.
• predetermined measures can be initiated, for example, as already mentioned above, the immediate opening of the door.
• FIG. 4 shows a sensor device 42, which is provided for monitoring a door opening 43 with a door 44.
• the door 44 is e.g. a sliding door that moves in a plane perpendicular to the plane of the drawing.
• the sensor device 42 has a light source 2 and a receiving device 3.
• the light source illuminates straight down in a region 49.
• the sensor device 3 looks down in a region 50 to monitor the door opening.
• a part of the emitted light 45 of the light source 2 is deflected by a mirror element 46 in the direction of the door 44. If the light beam 45 strikes the door, it is reflected as reflected light 47 to a mirror element 48, which reflects the light into the receiving device 3.
• the reflection at the mirror elements 46 and 48 can be done by reflection and / or by total reflection.

Landscapes

• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Electromagnetism (AREA)
• Computer Networks & Wireless Communication (AREA)
• General Physics & Mathematics (AREA)
• Radar, Positioning & Navigation (AREA)
• Remote Sensing (AREA)
• Optical Radar Systems And Details Thereof (AREA)
• Measurement Of Optical Distance (AREA)
• Length Measuring Devices By Optical Means (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Related Child Applications (1)

Publications (2)

Family

ID=40651852

Family Applications (1)

Country Status (6)

Families Citing this family (5)

Family Cites Families (19)

• 2008
  • 2008-11-20 AT AT08020219T patent/ATE539361T1/de active
  • 2008-11-20 EP EP08020219A patent/EP2189813B1/de not_active Not-in-force
• 2009
  • 2009-11-19 CN CN200980154526.2A patent/CN102282479B/zh not_active Expired - Fee Related
  • 2009-11-19 JP JP2011536773A patent/JP2012509470A/ja active Pending
  • 2009-11-19 WO PCT/EP2009/008241 patent/WO2010057637A2/de not_active Ceased
• 2011
  • 2011-05-19 US US13/111,261 patent/US8462320B2/en active Active

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