FIELD OF TECHNOLOGY

Generally looking subject invention belongs to the field of absorbers and electromagnetic radiation attenuators and it particularly refers to dielectrical ferrite absorber being used for reducing detrimental effects of mobile phone transceiver antenna electromagnetic radiation.

According to the International Patent Classification (Int. Cl.7), subject invention has been sorted i.e. classified and marked with H Ol Q 17/00 primary classification symbol referring to devices for wave absorption with active antenna elements or systems as well as with H 01 F 1/10 secondary classification symbol defining magnets or bodies characterized by material used - ferrites for example.

TECHNOLOGICAL PROBLEM

Technological problem being solved with subject invention comprises the following: How by using certain technological method to produce ferrite absorber consisting of several elements providing that active principles of components provide significant absorption, attenuation and reflection of high frequency electromagnetic waves for mobile telefony operation at the position being during use of mobile phones closest to the head of the user or being rested on it, in order to significantly minimize effects of these waves on brain and other cells; at the same time this kind of absorber should be efficient, reliable, small and compatible in aesthetic sense with modern design requirements and economically acceptable for mass usage. STATE OF TECHNOLOGY

Modern mobile telephony which extended communication among people and information transmission to unforeseen extent has become part of modern world standard and is spreading extremely fast over the whole planet. Although until recently it has been the privilege in the richer part of the developed world as well, owing to technological progress, and above all owing to desire to accomplish high profits fast it has been made available for almost everyone so it has been brought into mass usage by the developing countries population as well. Base station networks of this telephony are continuously spreading with dizzy speed providing audibility at almost all regions including the farthest. At the same time aspiration for prestige on the market leads to increase in mobile phone functions accompanied by constant changes in the design. In such a way phones become smaller and antenna transceiver device is at large number of new models integrated into mobile phone casing. Some of these changes as a consequence have increased transmitter power as well as increased operating frequency of the device. Used rarely and for brief conversations at the beginning they are now used frequently and for long-lasting conversations.

It is well known that mobile phone radio transmitters emit radio signals being propagated in the form of high frequency electromagnetic field. Nowadays in mobile telephony various antenna structures are being used depending on the operating wavelength and they are all characterized by basic technical parameters (radiation pattern, directivity characteristics, radiation angle, directivity coefficient, self antenna wavelength, radiation resistance, frequency bandwidth etc.). Alternating electromagnetic field being propagated in the space around antenna is electromagnetic wave, and electromagnetic waves being used in RF technology are radio waves. It has recently been proved that radio waves represent special form of matter in motion in which mass and energy are present and that radiation field consists of two mutually connected fields - electric and magnetic existing at the same time and being mutually supported. Electromagnetic field propagation rate is aproximate to the velocity oi light and radio waves progation rate is zyoυυυ κm/s ana is aπectea Dy εr (relative dielectric constant) and μr (relative magnetic permeability of the environment).

Considering that it is known that antenna radiates electromagnetic energy more efficiently if current passing through it is at higher frequencies, mobile telephony operating frequency has constantly being increased thus devices operating at frequencies of 900 MHz and 1800 MHz are widely used today.

Radio waves transmit electromagnetic energy intensity of which being characterized by energy (power) flux density or by Poynting vector. Poynting vector is determined from the following equation:

π (W/m2) = E (V/m) x H (A/m)

where E represents electric field intensity and H represents intensity of radio waves magnetic field. Energy (power) flux density depends on the distance of radiating elements (radiators) from the place where wave comes and it is inversely proportional to square of the distance to the radiator.

Alongside with spreading of mobile telephony application research on its biological effects has been started. The knowledge that man is not capable of feeling the effects of electromagnetic waves with his senses, beside curiosity invokes fear of their unwanted effects, above all on brain cells. Today electromagnetic waves effects are well known but many important matters and theoretical postulates referring to disturbance in normal biological relations in brain cells are ignored or mindfully passed over because of necessity of mobile phones usage, obtained habits derived from its practicability and operability, and even more than above mentioned because of the profit gained by manufacturers and merchants. Although mobile phone radiation is of radio and not of ionising kind of radiation, the fact being used for the claim that it does not have power to destroy chemical oonαs oeτween moiecuies ana uamage me ceil, ir is purposely ignoreα mat tney nave electromagnetic component as well as the fact that resonating waves induce electrical pulses in the cell replacing electrochemical pulses leading to changes in cell functions which may lead to minor or major degenerative changes. Although obtaining exact data on detrimental effects of high frequency RF radiation requires long and hard work on which however more and more care is being taken, today it can be claimed with certainty that exposure of human body, above all brain cells, to long-lasting effect of mobile phones radiation leads to detrimental effects and rate of occurence of the disease is proportional to electric field magnitude and frequency and time of exposure. Today it is also known for certain that brain cells are lenghtened in form and more than other cells sensitive to effects of resonating waves, and there are numerous indicators and more claims that their exposure to long-lasting effects of high frequency electromagnetic radiation leads to tumourous effects. Referring to stohastic, random statistic phenomenons, occuring when detrimental effects on organisms occur completely independently of high frequency electromagnetic radiation influence is not valid and is frequently used and conducted in order to hide exact evidence on existence of detrimental influence of this radiation users must be familiar with.

With the objective of health protection parameter SAR (Specific Apsorbation Rate) has been introduced; it is internationally approved measure for determining the possibility of cell damages caused by mobile phone radiation. This criterion is used to determine the quantity of radio frequency being absorbed by organism and is expressed in the number of Watt radiation per kg of brain mass (W/kg). According to widely approved standards 1.6 W/kg is value representing acceptable SAR value with note - lower SAR value - radiation is less dangerous for human organism. In several more developed countries regulations have already been adopted obliging mobile phone manufacturers to underline at visible position of the device quantity of radiation emitted during usage.

Besides close examination of available patent documentation as well as vocational literature referring to field of protection from mobile phone radiation as well as usage of ferπtes as electromagnetic waves absorbers, similar tecnnicai soiuuon Dy eiiect oi sucn would efficiently and with complexity reduce detrimental effects of broadband electromagnetic waves on human body in the way it has been done with subject invention has not yet been found.

EXPOSITION OF THE ESSENCE OF THE INVENTION

With newly designed ferrite absorber for reducing detrimental mobile phone radiation and method for its production the above defined technological problem has been solved.

The essence of the invention is reflected in the fact that absorber substantially reducing detrimental effects of electromagnetic radiation of high operating frequencies of mobile telephony, according to the idea of the inventor, has been designed as thin multilayered tile made of magnetic-dielectric material with thin aluminium layer deposited above the material. In such a way subject invention combines and utilizes three protective functions - attenuation, absorption and reflection of electromagnetic field being during use of mobile phone closest to the head of the user or touching it and as such being most endangered.

The essence of the invention is also represented by the fact that ferrite absorber in accordance with the aims of the designer to be as universal as possible, has been made as broad band and as such is efficient for different high frequency bands being achieved by implementation of complex ferrites: manganese (Mn), zinc (Zn) and nickel (Ni) having the characteristics that at high frequencies ranging from 1 MHz to 10 GHz depending on the ferrite composition, successfully absorb electromagnetic waves up to 95 %, as well as dielectric made of synthetic rubber and chlorinized polyethylene having at room temperature specific electric resistance p = 106 to 108 Ω rnπrVm. Valence band of the dielectric is filled with electrons while conductive band is totally empty meaning that its electrons take part only in phenomenons where crystal lattice transmits energy sufficient to excite electron from valence to conductive band. Considering that number of situations like this is relatively small, it is clear that dielectrics are cnaracieπzeα oy us oasic property - attenuation of electromagnetic waves propagating through them.

The essence of the invention is also reflected in the fact that structure of subject absorber has been made in such a way that it is small, thinlayered, it does not spoil the mobile phone aesthetic design and it insignificantly reduces its technical characteristics because transceiving electromagnetic waves toward base station and vice versa unfolds freely at part of the space not being protected by the absorber simply by moving the device to the position with best audibility.

The essence of the invention is also represented by the fact that influence of absorber tile on the device is such that with its capacitive and inductive effects it does not invoke occurence of eventual parasitic couples between individual circuits in the device which could disturb its normal operation during receiving or transmitting signals.

Compared with until today known technical solutions concerned with problems of protection from mobile phone detrimental effects during their use, subject invention has several advantages, the following being among the most important ones:

- its implementation is fast, simple and it can be done by the mobile phone user himself; it is light, thin and it does not spoil the aesthetic design of modern mobile phones; - it covers wide range of frequencies so it can successfully be implemented into mobile phones operating at various frequencies; - during designing and producing of new phones it is possible to integrate it in the casing of the device; it is possible to adapt it to all types of mobile phones with antenna integrated in the casing being already in use by simple programming of compress during production of the absorber itself. SHORT DESCRIPTION OF PICTURES AND DRAUGHTS

With the objective of easier understanding of the invention, as well as because of showing how it can be obtained in practice, the author is only for the purpose of example referring to the enclosed draught related to ferrite absorber for reducing detrimental effects of mobile phones and where:

appearance of the absorber when it is affixed to mobile phone casing is shown in the picture 1.; - the absorber with certain layout of openings for passing sound from the device is shown in the picture 2.; - the absorber with modified layout of openings for passing sound from the device is shown in the picture 3.; - the absorber with different layout of openings for passing sound from the device is shown in the picture 4.; - vertical V-V cross section of the absorber from picture 2. is shown in the picture 5. DETAILED DESCRIPTION OF THE INVENTION

By viewing the enclosed pictures it is easy to recognize that ferrite absorber for reducing detrimental effects of mobile phones is made as self-adhesive multilayered tile the form of which being during production simply by cutting according to certain template adjusted to all casings of mobile phones with antenna integrated in the casing. Base of the ferrite absorber represents 1.2 mm thick layer made of ferrite powder and elasthomer being produced and formed into strips by method of thermoplastic extrusion. Ferrite powder is composed Of Mn024, Zn064, Ni0<12, Fe2O4 and it is produced by dry homogenization of oxides of aforementioned components, being after that subjected to chemical reaction at temperatures ranging from 900 °C to 1000 0C, and afterwards by dry milling method in vibrating mill pulverized to dsr = 1.2 μ - 1.4 μ particles. Ferrite powder obtained in such a way is then homogenized with thermoplastic binder - elasthomer. As elasthomer synthetic rubber as well as chlorinized polyethylene are used, and the process of homogenization of ferrite powder and elasthomer is done by mixing in the mixer whereupon the obtained composite material is being granulated. From in such a way obtained material «1.2 mm strips are produced by thermoplastic extrusion. On one side of such ferrite strip layer 2 of 0.1 mm thick aluminium is deposited by some of known methods for metalization of aluminium, vacuum vapourization or by gluing aluminium foil, while on the opposite side during the method of theromplastic extrusion on the whole surface adhesive strip 3 is fixed in two layers. Multilayered tile attained in such a way is then formed by cutting according to the desired shape (in the example of the production of the invention Faraday oval has been used) but form and size of the ferrite absorber are adjusted to form and size of the casing of mobile phone absorber shall be mounted on. Forming of opening 4 being also simply attained by drilling the material and adjusted in accordance with opening on the earphone on mobile phone is done in parallel with excenter compress work with appropriate tools. Openings 4 may also be vertical with equal cross section on the whole length but in the example of production of the invention they are conical and chamfered for 15° related to the absorber plain, because such making of the openings 4 during passing ot electromagnetic waves through them leads to superimposing and mutual attenuating effects caused by interaction of initial wave and wave formed by reflection on the opening edges partially reducing detrimental effects of radiation through openings.

Ferrite absorber attained by the above mentioned method is glued on the earphone surface of mobile phone being by manipulation held closely to head or inclined on the user's head, where the distance between antenna radiator and organism cells is minimal and where effects of electromagnetic waves are the strongest and the most detrimental. Protective function of subject invention is achieved in the following manner: electromagnetic waves which in their motion come on the ferrite absorber are first attenuated and absorbed (90 % to 95 %) because of the property of layer 1 dielectric ferrite and converted into thermal energy and lesser part passing through this layer is reflected from aluminium foil 2 and absorbed again by passing through layer 1. In this way, according to Lobus diagram, in antenna radiation field towards the brain of the user «dead angle» is made at the shortest distance between the device and the head of mobile phone user whereby detrimental effect of radiation is reduced and protection of those brain cells which would otherwise be the most endangered is achieved.

It is necessary to emphasize that during usage of subject absorber the following methods of prevention should not in any way be ignored:

- use fixed telephony whenever possible; shorten duration of conversations; use models at lower frequencies; use hands free sets; - avoid usage of mobile phones by pregnant women, children and persons with pace maker. MEANS OF INDUSTRIAL AND OTHER APPLICATION OF THE INVENTION

Industrial or other way of attaining ferrite absorber for reducing detrimental effects of mobile phones radiation, according to this invention is absolutely possible in compliance with method mentioned in this description, and experts from subject field may without any difficulties conduct the proceeding for production of subject absorber and make workmanship documentation by utilization of the data given in this patent application.

Production of the invention is possible in factories for production of soft ferrites and plastic ferrites. Apart from evident benefit of individual mobile phone owner by reducing detrimental effects and consequences of that effect of mobile phone radiation unquestionable benefit is achieved in wider social community because, according to the opinion of the author, a large number of diseases among mobile phone users should be prevented. Examinations done by the Institute for Physics — Laboratory for Electromagnetism on prototypes of the absorber have shown that they are very efficient in protection from radio radiation. Twolayered aluminium ferrite material is superior in this field, because it synergetically combines predominant absorber properties of ferrites with predominant reflective properties of aluminium. Transmission coefficient of radio emission power through twolayered aluminium-ferrite material, according to this invention, has been measured by conventional physical method of two layers and its numeral value is T <0.5 %. At the same time measured absorption coefficient has been A > 90 % (percentage).