RU2242798C2 - Identification device - Google Patents

Abstract

FIELD: identification technologies.

SUBSTANCE: device has open-frame integral circuit, inductiveness coil and capacitor, forming an antenna and mounting board, made of polyamide stripe with one-sided metallization, on which in longitudinal direction by methods of thin-film photo-lithography two commutation current-conductive tracks are formed, while stripe is folded in several times with folding radius no less than thickness of commutation conductors and glued between folded parallel portions by glue with thickness of glued seam being no less than thickness of said conductors.

EFFECT: lower dimensions, lower laboriousness, broader operation temperatures range and, thus, broader range of application.

2 cl, 2 ex

Description

The present invention relates to the field of identification of persons, stationary or moving objects, products and similar objects, namely portable electronic means such as a label or tag, which allows to detect and identify the object to which such a tag is attached. The device can be used to identify and allow people to access certain rooms, workplaces or to terminals of communication and information systems, search and recognition of animals, marking biological samples, chemicals and medical instruments, in automated security systems, electronic payment systems and other systems.

A known design of a high-frequency identification device (label) mounted on a flexible board. The device that transmits a signal with identification information in response to a request from the polling system includes a flexible board with an encoder IC located on it for recording identification information, an antenna and a generator that transmits an RF signal modulated by identification information to the antenna. The device can be manufactured by creating on a flexible substrate, for example, a polyethylene, printed circuit conductors using conductive inks based on graphite or silver [1]. The device can be made in the form of a bracelet and can be used to access protected areas. The disadvantage of this device is the rather large dimensions and the need to use an internal power source to provide communication at a distance of 10-50 m, since otherwise the range of reliable communication between the polling system and the device is sharply reduced.

The closest in technical essence to the proposed device is a high-frequency identification circuit designed to be embedded in the device recognition (identification) of objects. The circuit contains a polymer substrate, on both sides of which elements using the technology of the printed circuit boards are formed or integrally connected with it using the resistance of the substrate as a component of such elements [2]. The disadvantage of the proposed technical solution is the difficulties associated with the possible use of the circuit in devices that do not have a planar design, since the presence of elements on both sides of the substrate prevents it from being embedded, for example, into small bulky products such as tags, buttons, cylindrical objects of small diameter . In addition, the use of the conductivity of the substrate leads to the need to take measures to exclude the appearance of spurious bonds between individual elements of the circuit and in the device itself.

The basis of the invention is the creation of an identification device design, devoid of these disadvantages, and allowing to significantly expand the scope of such devices. The device should not contain internal power sources, operate in a wide temperature range, have small overall weight and weight indicators, reproducible with high accuracy parameters and provide a communication range of at least 50 m.

The solution to this problem is achieved by the fact that in an identification device containing a frameless IC for recording and issuing identification information, an inductor and a capacitor forming an antenna for bi-directional contactless communication with a polling system, and a mounting plate, the board is made of polyimide tape with one-side metallization. The use of polyimide allows you to expand the range of operating temperatures of the device. Using a thin-film photolithography method, switching (connecting) paths are formed from the metallization layer parallel to the edges of the tape. After mounting the remaining elements of the device on a tape, it is folded several times so that its individual sections remain parallel and glue them together. In order to prevent unwanted contacts of individual areas of the patch tracks, they are coated with a protective layer, for example, a photoresist. To prevent peeling of the conductors, the radius of the bend of the tape should not be less than the thickness of the conductors, and the thickness of the adhesive joint lies within one or two thicknesses of the conductors. However, windows can be opened in certain places on the protective layer, through which, at a given interval, the switching paths in different sections can be connected through additional capacitors, forming customizable inductive elements. In addition, the electrodes created on different tracks, departing from them towards another track, but not connected to it, mutually overlap in different sections and form capacitors that accumulate electric charges, which are used to power the IC. For this purpose, diodes can be introduced into the device for charging the indicated capacitors with a high-frequency voltage induced in the antenna. Due to this, the dimensions of the finished device are significantly reduced, there is no need to connect the switching tracks through the through metallized holes in the circuit board and it becomes possible to complicate the functional diagram of the device without introducing additional physical elements.

The design of the proposed device can be illustrated by the following examples.

Example 1. The layout of the identification device was assembled on a flexible mounting tape made of a polyimide film coated with a 10 μm thick aluminum layer. Conducting patch tracks were formed with a resolution of thin-film lithography (width 50 μm). The length of the tracks, and therefore the initial dimensions of the tape segment, was chosen from the need to obtain a resonant frequency of 13.6 MHz with a loop capacitance of 180 pF. The path inductance was 1.015 μH, and the dimensions of the circuit board when folded were 2.5 × 1.5 mm. An organosilicon compound was used to glue board layers.

Example 2. In a similar manner to that described in Example 1, a polyimide circuit board with dimensions of 2.5 × 3.5 mm was manufactured. A frameless IC was mounted on the board, then the board was folded, its edges glued together and it was placed in a wire inductor with an inner diameter of 2 mm. The resulting microassembly was tested as part of an identification system operating at a frequency of 150 kHz. The detection range was 62 m.

Using the proposed design of the identification device in comparison with the prototype provides a reduction in size, expands the range of operating temperatures, allows the use of group methods of microelectronic technology in its manufacture and, accordingly, reduce the complexity. Thanks to this, the scope of such identification devices is expanding.

Sources of information

1. Patent WO 99/13441, MKI G 08 B 13/187, application dated 09.09.1998.

2. Patent WO 98/40930, MKI G 08 B 13/14, application dated 03.03.1998.

Claims (2)

1. An identification device containing an open-circuit integrated circuit for recording and issuing identification information, an inductor and a capacitor forming an antenna for bi-directional contactless communication, and a mounting plate for mounting device elements, characterized in that the mounting plate is made of polyimide tape with one-side metallization, on which two electrical conductive paths are formed in the longitudinal direction, and the tape is folded several times with a bend radius of at least the thickness of the com mutation paths and glued between folded parallel sections of glue with a thickness of the adhesive joint is not less than the thickness of the conductors of the switching paths. 2. The device according to claim 1, characterized in that the coil and / or capacitor are formed by separate segments of two switching tracks located in parallel sections of the folded tape and interacting with magnetic or electric fields.