RU2481634C1 - Method to read operational labels with scanner creating additional scattered light flow for expansion of scanner reading zone - Google Patents

Abstract

FIELD: information technologies.

SUBSTANCE: method includes creation of a light flow with a lighting module of a scanner due to generation of a flow with sources of directed and scattered light. The zone of scattered light flow is increased due to application of an additional scattering cone-shaped light ring on a scanner, and light flows interact in accordance with a certain logic: a light flow (pos. 11 and pos. 12) is reflected from the surface with a label and gets via an optical system to a light-sensitive sensor, afterwards the field lighting level (pos. 11) is compared with the field lighting level (pos. 12). On the basis of comparison of lighting levels of these two light fields, the necessary control signals are generated for sources of light, which are arranged inside a lighting chamber (pos. 13) and outside the lighting chamber (pos.6), thus balancing the lighting of the common light field (pos. 12) and providing for high quality of scanning.

EFFECT: expanded zone of scanner reading due to creation of an additional scattered light flow with a lighting module of a scanner.

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Description

The invention relates to methods for reading (scanning) and decoding of product markings for their subsequent identification in order to protect products from fakes, forgery and falsification. In the applied labels of linear barcodes or two-dimensional labels of the Data Matrix type (ECC 200 standard), the information and verification parts form a single code word and consist of the same unit cells in the form of a square or rectangle. The application of a small but highly informative marking on the surface of the product provides a reliable way to track the entire production cycle of the product, control and maintain it during operation.

It is known that these labels are used to protect and identify objects using hidden marking, which is applied to the surface of the object in the form of a certain pattern with invisible paint that becomes visible in ultraviolet or infrared rays (RF patent 2107945, 03/27/1998) and is read from using special devices - scanners.

A disadvantage of the known marking method is that it does not allow recording identification information, but only gives an answer, an authentic document or not.

There is a method of optical marking of museum values (RF patent No. 2413989), however, while providing 100% protection of museum values from fakes, the method does not provide decoding of two-dimensional bar codes with high accuracy. So, when marking, for example, using an inkjet printer on the surface of glare and mirror-reflecting products from 10 attempts to scan, only 2 attempts were successful. To obtain a high-quality image scanning of a two-dimensional code, a contrast lighting device was used - illumination by directional light and diffused light fluxes. But this principle is excluded when marking glare and mirror-reflecting products due to the numerous mirror and background glare of the surface.

Also known is the marking of glare and mirror-reflective surfaces of products with the application of bar codes on a diffuse-reflecting sublayer, previously deposited on the surface of the product, larger than a two-dimensional bar code and not reacting with it (see RF patent No. 2432612), and the subsequent reading of these tags using readers - scanners.

From RU 96992 U1, 08/20/2010, a method is known for reading and decoding barcodes of various types, including symbol labels of direct application, using a portable reader including a housing with a trigger assembly, an optical part consisting of a lens and a lighting unit, hardware and software designed so that the optical and hardware parts are made in such a way that the pulses of the target designation LEDs of the lighting unit of the optical part do not coincide in time with the pulses of the LEDs under lights, and the optimal level of illumination is selected automatically, by adjusting the current in the backlight LEDs, while for lighting, LEDs with a narrow spectral range of radiation are also used. In order to point the scanner at the barcode, the light from two powerful LEDs passes through special lenses installed in front of them, then through the front optical cover and forms two bright spots on the subject. The pulses of the glow of the target designation LEDs do not coincide in time with the pulses of the glow of the backlight LEDs, so they are not visible in the image of the barcode received for decoding.

The most suitable type of label illumination suitable for subsequent digital processing is diffuse illumination. The design of the optical front cover of the scanner with slight energy loss transmits light from the side of the lighting unit to the subject and the light reflected from the subject to the camera lens.

When reading and decoding symbol labels of direct application (SMPS) from surfaces with a high reflection coefficient, using existing readers (scanners), there are certain problems associated with the selection of the illumination of the object. In this case, only scattered light is used to illuminate the SMPS.

The scanner lighting system design consists of two types of light sources:

- diffused light coming from inside the cylindrical camera of the scanner;

- directional light coming from a light source located on the outside of the cylindrical chamber.

When an object is illuminated (SMPS), for reading and decoding, the field illuminated by scattered light turns out to be limited by the inner hole of the annular part of the lighting chamber, which makes it difficult to read and decode SMPS commensurate with the diffused light field.

The technical task of the claimed invention is to increase the efficiency of reading and decoding of applied marks by the scanner, especially from surfaces having a high reflection coefficient (mirror and glare-forming surfaces), and simplifying the pointing (positioning) of the scanner on the marks. The stated technical problem is achieved by the method of reading (scanning) various labels, such as linear barcodes or two-dimensional labels of the Data Matrix type, deposited on the surface of various products, using a scanner that creates an additional diffused light flux, expanding the reading zone of the scanner, including creating a light flux by the lighting module scanner by forming a stream of sources of directional and scattered light, while the area of the scattered light flux is increased by using additional a sifting cone-shaped light ring on the scanner, and the interaction of the indicated light fluxes is carried out according to the following algorithm: first, the light flux through the outer holes of the scanner’s lighting chamber enters the scanned surface, then the light flux (pos. 11 and pos. 12) is reflected from the surface with a mark and gets through the optical system to a photosensitive sensor, after which the level of illumination of one light field (pos. 11) is compared with the level of illumination of another light field (pos. 12), and after To increase the illumination levels of light fields for light sources located inside the lighting chamber (pos. 13) and outside the lighting chamber (pos. 6), control signals are generated that are necessary to equalize the illumination of the resulting (formed) common light field (pos. 12) and ensure high quality scan.

So, to solve the technical problem and achieve the technical result, the claimed method proposes to increase the light field of the scattered light due to the directional light sources, for which the external ring-shaped optical fiber with lenses is replaced by a ring-shaped optical fiber of conical section with scattering properties in the design of the lighting system.

To ensure the most uniform field of scattered light, composed of two light fields, a special control algorithm is applied that allows to achieve the best results when reading and decoding SMPS from surfaces having a high reflection coefficient, and also greatly simplify the pointing (positioning) of the scanner on SMPS.

A portable reader (scanner) used to implement the inventive method for “capturing” and decoding, in particular, direct application character labels (SMPS) applied to individual parts and components, with the aim of identifying them and tracking the life cycle, is a modern powerful data collection tool . This device, which has a lighting system that allows you to expand the reading range, consists of a housing, a scanning module and an advanced illuminator camera. The scanning module, which is built into the housing, has a lighting chamber, which consists of two lighting systems - external and internal, creates a diffuse light flux illuminating the marks SMPN. Reflected from the surface with a mark on it, the light through a hole in the housing of the lighting chamber enters a sensor that reads the image of the mark. An improved lighting system with an additional diffusing cone-shaped emitter provides an increased recognition and reading area of SMPS from surfaces with different characteristics of reflection and absorption of the light flux.

Summary of the invention (description of the essence of the method)

To solve the above problem, a new method of forming an external diffused light flux and an associated algorithm for providing lighting are proposed. This invention allows to provide the ability of the scanner to read linear and two-dimensional marks, significantly increase the useful area of the scan. This will significantly increase the likelihood, quality of reading and recognition of scanning objects on any type of surface when they are comparable with a conventional scanning zone. The algorithm for selecting the necessary combination of illumination of directional and scattered light used in this invention allows to provide high quality scanning of linear and two-dimensional marks from glare and mirror-reflective surfaces.

In this invention, it is possible to use several types of point sources of directional and scattered light having different emitting optical characteristics.

This allows you to apply this invention for the recognition and reading of marks of various types applied to the surface with dyes that are invisible in the normal light range. The time separation used in this case of combined diffuse lighting sources and aiming sources makes it possible to use not only conventional LEDs, but also laser ones as a target for scanning, which, of course, improves the consumer properties of the reader.

Brief Description of the Drawings

Features of the invention, which are considered the latest, for better understanding are set forth in combination with the accompanying drawings. Figure 1 is a scanner image of linear and two-dimensional marks with a special scattering cone-shaped ring, the configuration and location of which provide the optimal combination of diffuse illumination of the scanning object.

Figure 2 on the left shows the formation of a light spot in the location of the scanned label for the existing prototype scanner. In this case, the total light spot (pos. 11) consists of two light fluxes: diffused (pos. 7) and directional (pos. 9), and the size of the light spot in this case has certain boundaries associated with the design of the lighting module. The proposed method for increasing the size of the total light spot is to replace the directional external light emitter with a scattering light (Fig. 2 on the right, pos. 5). With this method, the size of the total light spot (pos. 12) is significantly increased, while leaving the dimensions of the lighting module unchanged and not changing the design of the entire optical system of the prototype. From the above figure 2 it is seen that the light spot (pos.11) significantly increases (pos.12) due to the additional light field (pos.10). To ensure the uniformity of the scanning area of the label, the light source control system selects the necessary light ratio.

The application of this method allowed to increase the number of successful scanning attempts, but did not reduce the number of technological operations and the consumption of materials when applying marks on the surface of products.

To prove the compliance of the invention with the conditions of patentability and industrial applicability, we give examples of specific performance. These examples do not exhaust the essence of the proposed method according to the invention.

Example 1

Figure 1 and figure 2 presents a variant (example) of the method. Figure 1 presents a variant of the General view of the scanner with an additional scattering conical ring. Figure 2 presents the lighting module and the scheme for the formation of additional diffused light flux to expand the read zone, without increasing the diameter of the lighting chamber. A scanner for reading linear and two-dimensional marks is a device that includes a housing (item 1), a special lighting module (item 3), a special optical system with a lens, target indicator and sensor (item 2), structurally located inside the case which, interacting according to a unique algorithm, provide reliable reading and recognition of scanning objects located in the scanning zone.

The composition of the special lighting module (Fig. 2) includes a special camera (pos. 4) with sources of directional and stray light (pos. 6 and pos. 13). Scattered light is formed inside the camera due to its multiple reflection from its walls and leaves it through an external hole (pos. 7), reaching the object of scanning. Directional light is formed on the outside of the camera around the hole through which diffused light exits. To generate directional light, point sources and special focusing lenses (pos. 8) are used, which create a directional light flux (pos. 9). The luminous flux of pos. 11 and pos. 12 is reflected from the surface with the mark and passes through the optical system to the photosensitive sensor, after which the level of illumination of the field pos.11 is compared with the level of illumination of the field pos.12. Based on a comparison of the illumination levels of these two light fields, control signals are generated for light sources located inside the lighting chamber pos.13 and outside the lighting chamber pos.6, thus aligning the illumination of the general light field pos.11 and pos.12 and ensuring high quality scanning . The system of combined diffuse illumination of the object to be scanned by both diffused and directional light scans SMPN codes and marks on any type of surface, including shiny, metallic and mirror surfaces.

A transparent and glare product, such as an ampoule, is pre-marked with a bar mark using an inkjet printer. This label does not provide decoding of a two-dimensional bar code with the isReader C-1 scanner, since there is no clear and high-quality reflection of it (see Fig. 3).

Example 2

The bar mark applied to the ampoule is read and decoded by the scanner with an additional scattering cone-shaped ring (see figure 4).

Used technical means for marking and scanning: EBS-6100 inkjet printer, isReader S-1 symbol mark scanner, OLYMPUS camera.

A combination of the use of invisible and visible ink is possible when marking museum exhibits. This serves as additional protection against fakes of various museum rarities and antiques, eliminates their duplication through the use of the latest technology.

Thus, as follows from the description, when implementing the method according to the invention due to, in particular, expanding the reading zone by forming an additional diffused light flux, in combination with the selected certain interaction algorithm of the generated light fluxes and other indicated features, an increase in the efficiency when reading and decoding labels is achieved , including symbolic labels of direct reading from surfaces having a high reflection coefficient. In addition, the process of pointing the scanner to the tags is simplified.

Claims (1)

A method of reading (scanning) various marking marks, such as linear barcodes or two-dimensional marks of the Data Matrix type, deposited on the surface of various products, using a scanner that creates an additional diffused light flux and expands the reading zone of the scanner, including creating a light flux by the scanner lighting module by forming a stream with sources of directional and scattered light, while the area of the scattered light flux is increased with the help of an additional scattering cone-shaped light ring on the scanner, and the interaction of the indicated light fluxes is carried out using the following algorithm - first, the light flux through the external opening of the scanner’s lighting chamber enters the scanned surface, then this light flux (pos. 11 and pos. 12) is reflected from the surface with the mark and gets through the optical system to a photosensitive sensor, after which the level of illumination of one light field (pos. 11) is compared with the level of illumination of another light field (pos. 12), and after comparing the levels of illumination In these two light fields for light sources located inside the lighting chamber (pos. 13) and outside the lighting chamber (pos. 6), control signals are generated that are necessary to equalize the illumination of the resulting total light field (pos. 12) and to ensure high quality scanning .

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