DE60038636T2 - Apparatus and method for reading and decoding optical codes with result display - Google Patents

Description

The The invention relates to a device and a method for reading and Decoding optical codes with an indication of the result of the Decoding itself.

In In this description and the claims which follow, the term "optical code" is intended to mean bar codes, batch codes, d. H. with a variety of stacked stroke sequences, two-dimensional Codes, color codes and the like.

Further is with "reading a optical code "or" detecting an optical Codes "the entire lighting (or scan; scan) the code with a light beam, capturing of the light emitted by the code and its conversion into electrical Signals meant while with "decode an optical code "the Processing the electrical signal and its interpretation or decoding is meant.

Finally is with "Display of the Decoder result "too the mere Display of the end of decoding or unsuccessful Meant decoding attempt.

Known Devices for reading and decoding optical codes, or in short Readers essentially comprise a light source for generating a Beam of light reading on the optical code should, is projected, z. Through slots and lenses, here generally designated by the term "illumination optics", optical elements used to detect and focus on the Code radiated light are suitable, for. B. slots and lenses (generally designated by the term "receiver optics"), photosensitive elements to which the receiver optics detected Light is focused, which is suitable for capturing the code radiated light and to convert it into an electric Signal, wherein the electrical signal, the reflectivity modulations the code-forming elements as accurate as possible, as well as processing means for interpreting or decoding the code to contain the code contained therein to obtain significant information, e.g. B. Manufacturer, name of the specific product, production batch, price etc.

Of the Process of reading and decoding a special optical code can give negative results due to several factors, to these factors, the code's error due to e.g. B. damage of the label on which it is contained, the distance between the reader and the code or maintaining that distance while belong to the sampling time. Even if the code is detected correctly Furthermore, the decoding can be impossible, because he z. Eg not fall into one of the categories of codes that the reader knows, falls. In any case, the must Operator will know if the code has been decoded before using the reading of another code is continued.

These Problems are in the case of the so-called hand or hand-held Readers in the style of pistols particularly serious.

at Optical code readers are therefore known simple display devices and today in use to indicate to the user that the special targeted optical code was decoded by the reader.

These Display is usually generated by means of a light source, which is composed of one or more light emitting diodes (LEDs) is which in the body near the reader its outer surface or are arranged within the same. Because in both cases the LED from the outside must be visible The light emitted by the LED may be refracted and / or scattered be so that it for the Operator is more visible. The image of the reader body is located However, usually at the edge of the field of view of the operator whose Focusing on the optical code is focused. This is especially true for codes of small size or for batch codes whose detection requires precise hand movement. The perception of the lighting of the LED in the body of the Reader is therefore not necessarily immediately.

Around the perception of giving that reading and decoding is done, even in the event that the visual Attention of the operator not focused on the reader is usually the illumination of the LED is usually from an acoustic Signal accompanied, the z. B. of an electromagnetic acoustic Signaling device is provided, usually a buzzer or a beeper. However, this provision is not completely satisfactory, because the acoustic signal can not be heard well when the process in a noisy environment or by an operator with one impairment of hearing. Furthermore, one can often repeated acoustic signal for the operator who very often and / or over to scan for a long time is very annoying.

The European Patent Application No. 98830656.9 by the same Applicant, which is a prior art document under Art. 54 (3) EPC, describes an optical device having at least one illumination arrangement, which in one part the reading region is active along an optical transmission path, said at least one illumination arrangement having the following features: a light source; a membrane having a predetermined shape for selecting a portion of the light generated by the source; and a converging lens disposed downstream of the diaphragm for collimating the shaped light coming from the diaphragm and projecting onto the portion of the reading area.

These However, device is for sighting and visual display of the area where the optical code lies, while the above document does not Display of the use of such a device provides for the result the decoding of the optical code.

Patent Abstracts of Japan, Vol. 1996, No. 12, 26 December 1996 and JP 08 202806 A on which the preamble of the independent claims is based, describes an apparatus and method for reading and decoding optical codes in which, after decoding an optical code, a red detection light source is turned off and a green light is emitted at the optical code.

US 5,140,141 discloses a bar code reader mounted on an arm with an LED mounted on the housing for indicating whether the code has been successfully read or not, and a display means for giving the operator a direction, a position, and an area or zone an item must pass through with a bar code for the bar code to be successfully read by the scanning system. The display means may comprise another LED mounted on a display bar directed to the bar code to be read. This additional LED is activated when the barcode is activated. Alternatively, the LED would be activated when the reader is in a stand-by mode or when a read error occurs, having a color that does not differ from the laser light used for scanning. The operator may know that the bar code has been successfully read by the scanning system by detecting a light jacket covering the other LED as it powers the other LED.

Of the Invention is the technical problem underlying a device and to provide a method of reading optical codes having improved capabilities for providing a visual indication of the decoding result, the by the operator is immediately noticeable.

A ambitious task of the invention is one such To provide apparatus and a method in which the display of the LED coding result is more significant, d. H. has a greater information content.

This Problem is inventively an apparatus and method for reading and decoding optical Codes solved according to the independent claims.

Further Features and designs The invention will become apparent from the dependent claims.

A visual display of the decoding result by the operator can be provided directly by a Light figure is projected onto the just read optical code, d. H. to the position on which the attention of the operator is focused. By using a light figure distinguishable from the detection light pattern is an immediate visual indication of a successful or unsuccessful decoding result. Furthermore, it is possible according to the invention the code a big one Area more useful information for to project the operator, which is more complex and sophisticated is the end of decoding as the simple indication, causing the solved above second task becomes.

• – eine Erfassungsvorrichtung zum Erfassen eines Signals, das repräsentativ für den optischen Code ist, wobei die Erfassungsvorrichtung wenigstens eine Erfassungslichtquelle zum Beleuchten eines optischen Codes mit einem Erfassungslichtmuster aufweist,
• – eine Vorrichtung zum Decodieren des erfassten Signals, das repräsentativ für den optischen Code ist, und
• – eine Vorrichtung zum visuellen Anzeigen des Decodierergebnisses, wobei die visuelle Anzeigevorrichtung umfasst:
• – wenigstens eine Anzeigelichtquelle, die sich von der wenigstens einen Erfassungslichtquelle der Erfassungsvorrichtung unterscheidet, oder die wenigstens eine Erfassungslichtquelle der Erfassungsvorrichtung wird auch als die wenigstens eine Anzeigelichtquelle der visuellen Anzeigevorrichtung eingesetzt,
• – eine Vorrichtung zum Aufprägen eines Informationsgehalts, der das Decodierergebnis angibt, auf das Licht, welches von der wenigstens einen Anzeigelichtquelle ausgesandt wird, und
• – eine Vorrichtung zum Ausbilden wenigstens einer Lichtfigur mit dem aufgeprägten Informationsgehalt aus dem Licht, das von der wenigstens einen Anzeigelichtquelle ausgesandt wird, im Wesentlichen bei dem optischen Code.

According to a first aspect, the invention thus relates to an apparatus for reading and decoding optical codes, having the following features:

• A detection device for detecting a signal which is representative of the optical code, the detection device having at least one detection light source for illuminating an optical code with a detection light pattern,
• A device for decoding the detected signal which is representative of the optical code, and
• A device for visually displaying the decoding result, the visual display device comprising:
• At least one indicator light source different from the at least one detection light source of the detection apparatus, or the at least one detection light source of the detection apparatus is also used as the at least one indicator light source of the visual display apparatus;
• A device for imparting an information content indicative of the decoding result to the light emitted from the at least one display light source, and
• A device for forming at least one light pattern with the impressed information content from the light emitted by the at least one indicator light source, in the art essential to the optical code.

According to the invention the device for decoding the detected signal used for the optical Code representative is, means for distinguishing between at least two results the decoding, and the device for visually displaying the Decoding result is arranged so that at least one light figure for each result different from the discrimination means from the detection light pattern is distinguishable.

In this description and the following claims is with "essentially at the optical code "means: on the surface, which carries the optical code, and in big Near or in accordance with the optical code itself.

The Means for decoding the optical code advantageously comprise means to transfer of the detected Codes to a remote processing unit and to receive the Decoder result from this.

In an execution include the means of imprinting the information content a switch for switching on and off the at least one indicator light source. This version has the advantage that they very easy.

In an alternative embodiment include the means of imprinting the information content at least one element for selectively transmitting the Light generated by the at least one indicator light source becomes. With this provision, it is possible to generate light figures, such forms or shades have that Operator immediately recognizes that they are away from the lighting line which is used to capture the code by simply turning the light source on and off.

special can be the selective transfer element a breaking element, a membrane with a given shape, a slide, a reflective surface with a given Form and a closer be. In the case of a membrane, the predetermined shape z. B. exist in an elementary geometric figure, or she can a stronger one have suggestive content. When the light source is white light it is also possible to use a color slide. In the case of a reflective surface can the light transmitted to the projection device alternatively just be the reflected or just the light that does not reflect back becomes.

In Alternatively, the selective transmission element may be a refractive element Element or a hologram. In this case, the information content imprinted, by modifying the wavefront of the light beam. The breaking ones Elements can z. B. refractive grating, and the holograms can, for. B. computer generated holograms.

In another version include the means of imprinting the information content, a drive circuit of at least a light source. By properly driving the light source it is therefore actually possible, to get projected images where the operator immediately recognizes that she differ from the illumination line used to detect the Codes is used.

The Drive circuit is adapted to the at least one indicator light source Even under such operating conditions that the at least an indicator light source during the detection of the optical code is the detection light source. By providing a common light source for both the detection of the optical code as well as the display of the decoding result it is possible Size and costs to keep the device low.

Advantageous For example, the at least one indicator light source is a light source Can emit light with at least two chromatic components, and the drive circuit may be the at least one indicator light source such that they each Sometimes light is generated with one or more chromatic components. Included in this way the projected image has an informational content, by its color is coded. Further, one of the generated hues may be one which is needed to capture the code.

In In an alternative, the drive circuit may comprise the at least one Turn on the indicator light source at least intermittently. at this version it is also possible to produce projected images, which are characterized by interruption times can be distinguished and distinguished from the light that is generated by the detection light source and usually continuously is. The light source may further coincide with the detection source. This light source usually includes multiple LEDs or a laser beam, which is uniform for capturing the code sweeping over optical code, while for the Display of the decoding result of the light beam with interruptions or resting to produce a fixed spot of light.

Alternatively, the drive circuit may be adapted to modulate the intensity of the at least one indicator light source. In this way, it is also possible to produce projected images that differ from each other and from the detection light, which usually has a uniform and constant intensity, with both separate light sources and the same light sources used for the detection.

The Apparatus for forming comprises at least one convergent Lens for collimating the light or focusing it in the Essentially with the optical code.

The Device for forming advantageously comprises the illumination optics the detection device. This allows the device to be small and economical being held.

Corresponding For example, the device for forming the receiving optics of the detection device include.

The Visual display means also comprise second means for projecting of the light emitted by the at least one light source, or a second light from a second indicator light source is sent in the direction of the operator of the device. Alternatively or in addition the device may comprise audible indicator means comprising the associated with visual display means. While in this way, too, the usual Types of display are maintained, the device is suitable in practice for all operating conditions.

In an execution includes the device for impressing the information content a two-dimensional laser scanning machine.

According to one second aspect, the invention relates to a method for reading and Decoding of optical codes, comprising the following method steps: detecting a signal that is representative for one optical code is over an optical code reading device having a detection light pattern and receiving the light scattered by the optical code; To attempt the detected light, which is representative for the optical code is to decode; and visually displaying the result the decoding attempt by generating at least one light figure essentially the optical code.

According to the invention becomes a step of distinguishing between at least two results the decoding attempt carried out and the display step is performed by a predetermined Light pattern is generated by the detection light pattern for each In this step differentiated result is distinguishable. The Operator receives therefore in any case an advertisement.

The predetermined light figure can the respective different result be assigned to. By providing various ads that the associated with the respective decoded result, the operator receives in any case, an ad.

Of the Step of the visual display preferably includes the imprinting of a Information content on the light figure, which goes further than the mere statement, whether the optical code has been decoded or not.

In an execution The step of distinguishing between at least two Decoding results distinguishing between different reasons negative decoding result, and the visual display step includes the substep of imprinting an information content, indicating the reason of the negative decoding result to which at least one light figure.

alternative or additionally The step of distinguishing between at least two Decoding results according to at least a part of the Contents of a positively decoded optical code, and the step of the visual display comprises the substep of imposing a Information content, referring to the at least part of the Contents of the positively decoded optical code refers to the at least one light figure.

Of the Step of distinguishing between at least two decoding results becomes common executed by between a positive result and a negative result a distinction is made.

Of the Step of distinguishing between at least two decoding results is preferably distinguished by distinguishing between a positive result and at least two different negative results. On this way the operator can for example recognize if decoding due to causes related to the optical Code or due to a wrong operation of the reader is impossible and she can, as far as possible, the necessary corrective measures implement or otherwise give up further attempts.

Of the Step of displaying is preferably only after repeating the detecting step and the decoding step with a predetermined one Number of negative results. In this way, temporary Reading or decoding errors are automatically overcome.

The predetermined light patterns generated in the display step differ usually by hue, shape and / or dynamics of light intensity. In all three ways, or by a suitable combination, it is possible to transmit even complex information contents to the operator of the optical code reader.

Of the Step of displaying becomes common executed by also providing at least a second light information at the device for reading and decoding the optical code is generated.

The substantially in the optical code generated light information is also preferably turned off before the second light information in the device for reading and decoding the optical code is turned on. By this provision it is possible to have a short display of the ideal position and a longer visual display, if necessary not even in the ideal position to produce.

Further Features and advantages of the invention are now with reference to some versions explains the designs as non-limiting Examples in the attached Drawings are shown in which:

1 shows a partial view of an apparatus for reading and decoding optical codes with a display device, which is separated from the device for detecting the code;

2 schematically shows a laser display device for such a device;

3 shows a partial view of an apparatus for reading and decoding optical codes with a display device, which is integrated in the device for detecting the code;

4 shows a flow chart useful for the description of the method not according to the invention; and

5 shows another flowchart useful for the description of the method according to the invention.

1 schematically shows a part of a device 10 for reading and decoding optical codes. The receiving part of the optical code reader is equipped with a lens 12 that is a reception axis 14 has, and a sensor 16 while the part for illuminating the optical code is not shown.

The device of 1 in fact provides for the use of a completely separate light source and optics for indicating the result of detection of an optical code, the display being made by projecting a light pattern toward the optical code bearing surface.

More specifically, the in 1 the device shown a display device 20 in the form of a light source 22 , a membrane 24 which is substantially adjacent to the light source, and a lens 26 by a carrier 30 along an optical axis 28 is aligned.

In the simplest arrangement are the membrane 24 and lens 26 not essential, since the simple switching on an LED 22 is sufficient to impose the information content on the light display.

The light source 22 can z. Example, a light emitting diode (LED), which is preferably fed independently of other LEDs (or laser diodes), which are used in the reader for illuminating the code. The light source 22 must be sufficiently bright to produce a light figure that must be clearly visible even in a well-lit environment. LEDs available on the market, which are considered the light source 22 The LED models HLMP-CM15 from Hewlett Packard, Palo Alto, California (USA), for example, can be used with an epoxy housing with a diameter of 5 mm, a peak wavelength (λ) of λ = 524 nm and an emission angle of 15 °, or the LED model LT5413 from OSRAM, Munich, Germany, with a peak wavelength λ = 525 nm and a housing and an emission angle, which are equal to those of the aforementioned LEDs. These LEDs both emit green light.

The light source 22 the display device 20 can actually emit light of any color, but green light is preferred. In fact, green light is used universally to provide a positive indication or indication of faultless operation, as in traffic lights or the display LEDs of electronic equipment, and, in addition, the light of the light detecting device for detecting the code is usually red; Green light thus allows an emphasis on the difference in light emitted to illuminate the optical code for its detection.

The optical code reader may be of any type, with some LEDs and illumination optics for illuminating the optical code, and with receive optics and a CCD (charge coupled device) or C-MOS (Complementary Metal Oxide Semiconductor) type of receiving device the light signal coming from the code comes, and transforming it into an electrical signal. Furthermore, both sensor types can be linear or two-dimensional. The reader may also include any reader having a laser diode, illumination optics, and scanning device for generating a scan and thus illuminating the optical code and receiving optics in a photodiode for receiving the light signal from the code and transforming it be electrical signal. In the following description, the term "device (or light source) for illuminating the optical code and / or detecting the optical code" will be used without distinguishing the two types of optical code readers.

Further Both types of readers include means for processing the electrical Signals and decoding the read optical code. These funds for processing the electrical signals and / or for decoding of the code can "on board" the reader himself be included or they may be "removed". That means, that this electrical signal over a cable or over a cordless connection to a processing unit which removed from the reader, can be sent, this processing unit then tells you if the code was decoded or not. In the further Description will be the processing of the electrical signal and / or its decoding is termed "code decoding".

When an alternative to monochromatic LEDs in a limited band of the visible spectrum, it is possible to use LEDs, the one essentially white Send light or other variants, which is further described below is.

The membrane 24 should be part of the light source 24 block out emitted light. This membrane may have any shape, while its part transparent to the light radiation has the shape of the desired light figure which is to be projected as a visual indication of the decoding result on the optical code or in its immediate vicinity.

The membrane 24 can z. B. a circular free opening 25 include. The membrane 24 is advantageously substantially in contact with the LED 22 to pass a portion of the light through the free aperture as wide as possible. Furthermore, the membrane 24 be prepared as a separate part which is in the carrier 30 is inserted, or it can be directly in the carrier 30 be included.

As an alternative to the circular shape, the free opening 25 the membrane 24 have a different shape. To achieve an immediate display of the result, it may, for. B. be advantageous, free openings 25 to use with a more significant shape, such as a hook (√), a term such as "OK", "READ" or the like, a more complex figure, such as a closed hand with thumb up, or the manufacturer's logo. If, on the other hand, the result display represents the negative result of the decoding, it may be advantageous to use symbols such as an X, or terms such as "NO", "ERROR" or the like, or a more complex figure such as a closed hand with the thumb down. to use.

In addition, it is possible to use a plurality of membranes simultaneously illuminated by the same or corresponding sources to obtain a plurality of spaced-apart light patterns, or a membrane 24 with several free openings 25 , Furthermore, it is obvious that in each case the membrane 24 or the like of more than one LED can be illuminated to increase the intensity of the light figure.

The membrane 24 must be understood as an example of a device for imparting information content to the projected light, ie for generating a specific given figure. In this regard, the membrane allows 24 with the free opening 25 obtaining a projected image with only two levels of illumination (light and shadow). In order to obtain a gradation of intermediate light levels between dark and light, it may be advantageous to replace them by a membrane with variable light transmission or by a slide, which in the event that a light source 22 which emits white light may be a color slide.

In another alternative arrangement, that of the source 22 emitted light beam from a reflective surface which has substantially the same shape as the desired light figure to be used for displaying a result, and which is arranged so that it is a part of the light of the light source 22 interrupts and towards the lens 26 sends. In this case, the three elements are not along the optical axis 28 aligned. Alternatively, the reflective surface may be used to pass the non-reflected light as a display figure that is complementary to its shape. In this case, the back-reflected light z. B. can be used as the source of the traditional display device which transmits to the main body of the reading device.

According to the invention, the device comprises more than one display system 20 as shown by way of example, each used for a different indication. In addition to displaying the successful chen decoding it is z. For example, it is possible to indicate that the decoding of the optical code was not possible within a maximum time or with a maximum number of attempts. In this case, a red light figure should be used, eg. An X. It is even more preferred that the negative result of the decoding can be distinguished from a number of typologies, e.g. If the code is damaged or if in the special operating condition the reader can not execute the decoding or if the code is not among the categories given to the reader 10 are known falls. The generated display figure is distinguished in various ways, e.g. B. by their color and / or shape.

Equivalently, it is possible to use the display device to allow the projection of a variable light figure to provide more information to the operator of the device 10 provided. Even in the absence of a membrane, the light source 22 z. For example, from any group of two or more LEDs having a given geometric arrangement, a backlit liquid crystal display (LED), a segmented LED matrix as an alphanumeric display (e.g., those commercially available as SA05). 11SRWA, available from Kingbright, Taiwan, comprising seven-segment LEDs with a wavelength of λ = 660 nm representing characters with a height of 12.7 mm), or a dot-LED matrix (eg. commercially available as TA07-11SRWA from Kingbright, which is formed of 5 x 7 dots and has dimensions of 12.7 x 18 mm ² and emits light with a peak wavelength of λ = 660 nm). This alpha numeric display of the result can be used to display an error message explaining the reason why the code was not decoded. In the case of a positive result of the decoding of the optical code, the same display may at the same time provide information relating to the content of the read optical code or to a part of the code, e.g. The product or the name of the manufacturer or a category from a number of preselected categories. Each product can z. The location where it is stored, a possible discount applied to the product, etc.

alternative Is it possible, As a light source to use multi-chip LEDs, the two or more Include chips with different emission bands and independently turned on can be z. B. the red and green Dual-chip LED LU 53511-JM, which is commercially available from OSRAM, or RBG LEDs, such as Kingbright's KAA-3528EMBSGC LEDs. The last mentioned LEDs include three chips, which are the three primary colors (red, green and blue) and independent are controllable to the full Color range, which is perceptible by the human eye, too receive. That way you can the different colors are used to give special result displays to the operator provided.

The converging lens 26 that z. B. may be a simple plano-convex spherical lens made of plastic, which is obtained by molding, is used for projecting the light coming out of the free opening 25 the membrane 24 substantially in the direction of the optical code (or in any case the figure obtained by the above-described equivalent means). For this purpose, it is at such a distance to the membrane 24 arranged that the figure is focused on the surface of the optical code at a finite distance, in the reading area of the device for detecting the code of the device 10 falls.

Alternatively, the beam can be collimated, ie, the membrane 24 can through the lens 26 be focused at infinity to increase the size of the transmitted beam with increasing distance from the lens 26 to limit as much as possible.

The mechanical carrier 30 serves to receive and hold the above elements, namely the light source 22 , the membrane 24 and the lens 26 or their equivalents, in a fixed position. For this purpose he has appropriate seats, z. B. slots, the sake of clarity in 1 not shown. The carrier 30 is z. B. obtained by molding and is advantageously made in the same block containing the optical detection camera of the reader. This solution allows a greater reproducibility of the alignment between the axis of the illumination device, the receiving axis 14 and the axis 28 the display projector; Furthermore, such a solution allows faster assembly of the parts. Alternatively, the carrier 30 be provided in the housing, which the device 10 includes.

Every carrier 30 the display device 20 may be located at any point on the reader, provided that the display beam is not disturbed. At the in 1 As shown, the projection system is isolated and the associated carrier 30 is arranged above the optical receiving camera of the reader, the axis 28 parallel to the receiving axis 14 and is symmetrical with respect to a vertical plane passing through this receiving axis 14 goes. In this way, the center of the light figure and that of the illumination figure, usually a scan line, are separated by the same amount as the distance from the plane of the optical code changes.

Alternatively, the two axes 14 . 28 relative to each other, and they can intersect at a distance that is within the reading range to reduce the distance between the display figure and the lighting figure under normal operating conditions.

2 shows a further embodiment of the display device, the total with 40 is designated. This display device comprises a laser diode 42 as the light source, a collimating lens 46 formed of one or more lenses, and possibly a refractive element 44 or a hologram, which is downstream of the collimator 46 is arranged to generate the desired light pattern on the plane P (which contains the optical code or the surface containing it, touches).

The use of a laser 42 as the light source allows a brighter figure of light than would be possible even with high intensity LEDs. The use of refractive and / or hologram elements 44 in conjunction with the laser light, allows the creation of a sharp figure within a larger distance range. In an alternative embodiment, the refractive element or hologram 44 is omitted and the light figure is formed on the level of the code by a collimated laser beam, the target direction of which is gradually changed to draw a two-dimensional figure on the plane P. Systems of this type, so-called 2D scanning lasers, are known.

3 shows another device for reading optical codes, wherein the same optics of the illumination system for detecting the optical code is at least partially used for the visual display of the decoding result.

The device 50 includes a carrier 52 shaped to accommodate the elements necessary for illumination and reception during optical code acquisition. In addition to a lens 54 and the receiving sensor 56 , shows 3 the illumination source 58 and slits 60 as well as lenses 62 which form the illumination optics. More specific is the illumination source 58 shown with a plurality of LEDs, which usually emit red light, through the slots 60 is formed into a line. At least one additional or indicator LED 64 is provided which near the illumination LEDs 58 is arranged. The indicator LEDs 64 emit light, preferably a different color than the illumination LEDs 48 has, for. B. green light, so that the generated display figure consists of a line which is similar to the scan line, but has a different color. Alternatively or additionally, a membrane (not shown) or a corresponding element, as described above with reference to 1 in front of the (or each) indicator LED 64 are arranged to obtain a light figure having a shape other than the scanning line.

This solution allows the use of the same optics as the lighting system and therefore does not require, besides the LEDs, the introduction of additional components into the reading system. It's worth noting that from the indicator LEDs 64 emitted light does not interfere with the detection of the optical code, because the display LEDs 64 as will be described immediately, be turned on only when the detection has occurred, ie, when the sensor 56 is no longer active.

According to a modification, the display LEDs on the sides of the sensor 56 and the optics used to focus the display sources is the receiver optics (in the reverse direction). Also in this case, the display LEDs are only turned on when a detection has occurred, ie, when the sensor 56 is no longer active.

In an alternative embodiment are the sources of illumination used to capture the optical code also used to display the decoding result. In this case, other means of changing the on the optical Code of projected light used to impose the desired light figure.

If This shared source of illumination is monochromatic LEDs exist, which for The code capture must be able to illuminate the code as evenly as possible the change z. Example, consist of the various LEDs during the display by a suitable drive circuit (not shown) with interruptions on and off. Alternatively, the drive circuit may be a or switch on several LEDs at once (eg by the effect a moving line of light is generated) or change their intensity.

Alternatively, the shared light source may consist of multi-chip LEDs which, as described above with reference to FIG 1 include two or more chips with different emission bands and can be switched on independently, such. For example, the red and green dual-chip LED LU 5351-JM, which is commercially available from OSRAM, has a package diameter of 5 mm, which at the two wavelengths λ = 628 nm (red) and λ = 570 nm (green ) emits light with the help of two independently controllable chips. In this case, during acquisition, only the red chip of each LED is turned on, whereas during the display, the red chips are turned off, to activate the greens and change the color of the projected figure.

As mentioned above with reference to 1 As described, RGB LEDs, such as Kingbright's KAA-3528EMBSGC LED (SMD), comprise three chips emitting light with the three primary colors, red (λ = 625 nm), green (λ = 565 nm) and blue (λ = 430 nm), which can be driven independently to obtain the entire range of colors perceptible by the human eye. In this context, it is possible according to the invention to use a color, usually red, for the illumination during the detection and a series of colors for the display of specific results for the operator. Green can z. B. used to indicate that the optical code was properly decoded; Blue indicates that the optical code can not be decoded because it is out of the read range; Yellow indicates that the optical code can not be decoded because it is damaged; Violet serves to indicate that the optical code does not fall into a category known to the reader; Etc.

Laser lighting systems for the optical code detection can also as light sources for the Display of decoding results. Actually Laser reader for optical codes usually equipped with a mirror system for scanning the laser beam, that for creating a uniform scan line serves. The same laser source can be used for the display, by stopping the scanning system to get a fixed spot of light or by alternately turning the laser beam on and off becomes.

The various described display means may advantageously be associated with the visual display on the housing of the reading device and / or the acoustic display, which is normally provided in the prior art. This in 4 The flow chart shown indicates how the two displays can be advantageously managed. In this flow chart, for the sake of simplicity, only the case of displaying a positive decoding result will be referred to, where "LED 1" represents the display on the body of the device and "LED 2" represents the light source of the display device according to the various arrangements described above.

When starting in step 70 the device goes into a stand-by mode 72 , and LED 1 and LED 2 are both off (OFF). In this mode, the device waits for the beginning of reading, as by the query 74 shown, the z. B. is displayed by pressing a button on the device. During the capture 76 Both LED 1 and LED 2 are still both OFF (OFF) while the illumination source is operating. Once the optical code has been detected, the device checks in one step 78 whether it is possible to correctly decode the optical code. If not, she goes back to the stand-by step 74 , In the case of a positive decoding result, this is done in one step 80 by turning ON both LED 1 and LED 2. At this point, a predetermined time T must be in one step 82 elapse, at the end of LED 2 in one step 84 is turned off while LED 1 remains on while the device is in one step 86 waiting for the beginning of a new read to return to the capture step 76 enter.

The different switch-off times of LED 1 and LED 2 have their reason in the fact that the Display by projection requires a relatively powerful light source, so that it makes sense, a longer one Avoidance of excessive use of energy and too much the discharge of possible Batteries lead could. In contrast, the LED or other light source may be on the housing the reader sends, stay turned on, because they have a lower Energy intake has to decode the operator up to the next Display capture.

It However, it is obvious that the delay T is not absolutely necessary, and the two LEDs could be used for switch off the same time.

For explanation only, the flowchart of 5 the management of a display of both a positive result and a negative result, which is exemplified by the turning on (off) and turning off (off) of an OK and a NO LED. When switching on in one step 90 the device goes into a stand-by mode 92 , and the OK and NO LEDs are both OFF. In this mode, the device waits as directed by the query 94 shown at the beginning of a read operation, the z. B. is displayed by pressing a button of the device. During the capture 56 Both the LED OK and LED NO are both off (OFF) while the illumination source is operating. Once the optical code has been detected, the device checks in one step 98 whether it is possible to correctly decode the optical code. In the case of a positive result of the decoding this becomes in one step 100 by turning ON the OK LED. At this point must be in one step 102 a predetermined time T1 elapse, at the end of the LED OK in one step 104 is turned off while the device in one step 106 waiting for the beginning of a new read to enter the capture step 96 enter. In the case of a negative result of the decoding goes the setup of the query 98 to the display of this result in one step 108 with the LED NO turned ON. At this point, a predetermined time T2 must be in one step 110 elapse at the end of the LED NO in one step 112 is turned off while the device in one step 94 waiting for the beginning of a new read.

• – Erfassen eines Signals, das repräsentativ für einen optischen Code ist, über eine optische Codeleseeinrichtung mit einem Erfassungslichtmuster und Aufnehmen des von dem optischen Code gestreuten Lichtes
• – Versuchen das erfasste Signal, welches repräsentativ für den optischen Code ist, zu decodieren, und
• – Visuelles Anzeigen des Ergebnisses des Decodierversuchs durch Erzeugen wenigstens einer Lichtfigur im Wesentlichen bei dem optischen Code.

From the above description, those skilled in the art would understand that the described optical code reading and decoding apparatuses are particularly suitable for carrying out a method of reading and decoding optical codes, comprising the following steps:

• Detecting a signal representative of an optical code via an optical code reading device having a detection light pattern and receiving the light scattered by the optical code
• Try to decode the detected signal, which is representative of the optical code, and
• Visually displaying the result of the decoding attempt by generating at least one light pattern substantially at the optical code.

According to the invention The method further comprises the step of distinguishing between at least two results of the decoding attempt, and in the display step is the at least one light figure from the detection light pattern differentiated for each Result distinguishable.

Of the Step of visual display may preferably be the substep of imprinting an information content on the at least one light figure include where the information content is more than the mere statement, whether the optical code has been decoded or not.

Of the Step of distinguishing between at least two decoding results can distinguish between different reasons of the negative decoding result comprising, wherein the step of visually displaying the substep imprinting an information content that is the cause of the negative decoding result indicating that comprises at least one light figure.

alternative or additionally the step of distinguishing between at least two decoding results the discrimination according to at least a part of the content of a positively decoded optical code and the step of visually displaying comprises the substep of Aufprägens a content of information that relates to the at least one part the content of the positively decoded optical code the at least one light figure.

Of the Step of distinguishing between at least two decoding results can be executed in particular be between by a positive result and a negative Result is distinguished or by between a positive Result and at least two different negative results a distinction is made.

Of the Step of the result display is executed only when the detection step and the decoding attempt with a predetermined one Frequency of Receiving a negative result were repeated.

The predetermined light figure generated in the display step, In particular, a distinction is made according to hue, shape and / or dynamics of the light intensity.

Of the visual display step can be advantageously carried out by at least also a visual signal in the device for reading and decoding of the optical code is generated. In this case, the at least a figure of light that is essentially at the read optical Code is generated, turned off before the visual signal at the Device for reading and decoding the optical code switched off becomes.

Advantageous Furthermore, in all versions of the Be provided device or the method according to the invention, that the various options, each available from the operator through the Facility management software through both the normal user interface as well as by programming with predetermined codes that z. B. printed on the manual are selectable.

It It is obvious that numerous modifications, variations, Substitutions and insertions the described embodiments can be made Without departing from the scope of the invention, which is indicated by the following Claims defined becomes.

Claims (27)

Facility ( 10 ) for reading and decoding optical codes, comprising: a detection device ( 12 . 16 ) for detecting a signal representative of the optical code, wherein the detection device ( 12 . 16 ) comprises at least one detection light source for illuminating an optical code with a detection light pattern, a device for decoding the detected signal representative of the optical code, and a device ( 20 . 40 ) for visually displaying the decoding result, wherein the display device ( 20 . 40 ) comprises the following features: - at least one indicator light source ( 22 . 42 ), which differs from the at least one detection light source of the detection device, or the at least one detection light source of the detection device is also used as at least one display light source of the visual display device, 24 . 44 ) for impressing an information content indicating the decoding result on the light emitted by the at least one display light source ( 22 . 42 ), and - a device ( 26 . 46 ) for forming at least one light figure with the impressed information content essentially in the optical code, characterized in that the device for decoding the detected signal, which is representative of the optical code, comprises means for distinguishing ( 98 ) between at least two decoding results, and that the device ( 20 . 40 ) is arranged for visually displaying the decoding result so that at least one light figure is arranged for each of the distinguishing means ( 98 ) differentiated result from the detection light pattern is distinguishable. Device according to claim 1, characterized in that the device for decoding the optical code is a device to transfer the detected code to a remote processing unit and for receiving the decoding result thereof. Device according to claim 1 or 2, characterized in that the device ( 24 . 44 ) for impressing the information content comprises a switch to turn on and off the at least one indicator light source. Device according to claim 1 or 2, characterized in that the device ( 24 . 44 ) for impressing the information content at least one element ( 24 . 44 ) for selectively transmitting the from the at least one display light source ( 22 . 42 ) generated light. Device according to claim 4, characterized in that the selective transmission element ( 24 . 44 ) is selected from a group comprising: a refractive member, a diaphragm having a predetermined shape, a slide, a reflective surface having a predetermined shape, and a shutter mechanism. Device according to claim 4, characterized in that the selective transmission element ( 24 . 44 ) is selected from a group comprising: a refractive element and a hologram. Device according to claim 1 or 2, characterized in that the device ( 24 . 44 ) for impressing the information content comprises a drive circuit for the at least one light source. Device according to claim 7, characterized that the drive circuit is suitable for the at least one Indicator light source even under such operating conditions, that the at least one indicator light source during the detection of the optical Codes is the detection light source. Device according to claim 7 or 8, characterized in that the at least one indicator light source ( 22 . 42 ) is a light source capable of emitting light with at least two color components, and the drive circuit is the at least one indicator light source ( 22 . 42 ) so as to generate light with one or more color components each time. Device according to claim 7 or 8, characterized in that the drive circuit, the at least one indicator light source ( 22 . 42 ) can switch at least intermittently. Device according to claim 7 or 8, characterized in that the drive circuit the intensity of the at least one indicator light source ( 22 . 42 ) can modulate. Device according to one of the preceding claims, characterized in that the device ( 26 . 46 ) for forming at least one converging lens for collimating the light or focusing the light substantially at the optical code. Device according to one or more of the preceding Claims, characterized in that the device for forming the illumination optics the detection device comprises. Device according to one or more of claims 1 to 12, characterized in that the device for forming the Receiving optics of the detection device comprises. Device according to one or more of the preceding claims, characterized in that the optical display device ( 20 . 40 ) also a second device for projecting the light, which from the at least one light source ( 22 . 42 ), towards the operator of the facility ( 10 ) having. Device according to one or more of the preceding claims, characterized in that it further comprises an acoustic display device connected to the result display device ( 20 . 40 ) is linked. Device according to claim 1 or 2, characterized in that the device ( 24 . 44 ) for impressing the information content comprises a two-dimensional laser scanning machine. Method for reading and decoding optical codes with the following method steps: (a) detecting ( 96 (b) trying to decode the detected signal which is representative of the optical code (FIG. 4) by means of an optical code reader having a detection light pattern and receiving the light scattered by the optical code (FIG. 98 ), and (c) visual display ( 100 to 104 . 108 to 112 ) of the result of the decoding attempt (b) by generating at least one light figure substantially at the optical code, characterized by the step: (d) discriminating ( 98 ) between at least two results of the decoding attempt (b) and in that in the display step (c), the at least one light pattern is distinguishable from the detection light pattern for each result discriminated in the step (d). Method according to claim 18, characterized that the step of visually displaying (c) is the sub-step of Aufprägens an information content to the at least one light figure comprises where the information content is more than the mere statement, whether the optical code has been decoded or not. Method according to claim 18 or 19, characterized in that the step (d) of distinguishing between at least two Decoding results distinguishing between different ones establish of the negative decoding result and the step of visual Displaying (c) the sub-step of impressing an information content, indicating the reason of the negative decoding result to which comprises at least one light figure. Method according to one of claims 18 to 20, characterized in that the step (d) of distinguishing between at least two Decoding results distinguishing according to at least a part of Includes contents of a positive decoded optical code and the Visual display step (c) the sub-step of impressing an information content; which decodes on the at least part of the content of the positive optical code, to which at least one light figure comprises. Method according to one of Claims 18 to 21, characterized in that the step (d) of distinguishing between at least two Executed decoding results is made by putting between a positive result and a negative one Result is distinguished. Method according to claim 18, characterized in that the step (d) of distinguishing between at least two Decoding results by distinguishing between a positive result and at least two negative results are realized. Method according to one of claims 18 to 23, characterized the display step (c) is performed only after the detecting step (a) and the decoding attempt (b) with a given frequency of receiving a negative result. Method according to one of claims 18 to 24, characterized that the predetermined light figure generated in the display step (c) is distinguished according to hue, shape and / or dynamics of light intensity becomes. Method according to one of claims 18 to 25, characterized the display step (c) is carried out by continuing at least a second light information in the optical code reading device is produced. The method of claim 26, wherein the substantially in the code generated light figure is turned off before the second Light information is turned off in the optical code reader.