(19)
(11) EP 3 339 261 A8

(12) CORRECTED EUROPEAN PATENT APPLICATION
Note: Bibliography reflects the latest situation

(15) Correction information:
Corrected version no 1 (W1 A1)

(48) Corrigendum issued on:
29.08.2018 Bulletin 2018/35

(43) Date of publication:
27.06.2018 Bulletin 2018/26

(21) Application number: 17208625.8

(22) Date of filing: 19.12.2017
(51) International Patent Classification (IPC): 
C03B 37/012(2006.01)
C03B 37/027(2006.01)
 H01S 3/067(2006.01)
(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR
Designated Extension States:
BA ME
Designated Validation States:
MA MD TN

(30) Priority: 22.12.2016 PL 41994416

(71) Applicant: Instytut Technologii Materialów Elektronicznych
01-919 Warszawa (PL)

(72) Inventors:
  • Buczynski, Ryszard
    00-575 Warszawa (PL)
  • Pysz, Dariusz
    01-493 Warszawa (PL)
  • Franczyk, Marcin
    00-450 Warszawa (PL)
  • Klimczak, Mariusz
    04-274 Warszawa (PL)
  • Kasztelanic, Rafal
    05-830 Nadarzyn (PL)
  • Stepien, Ryszard
    03-188 Warszawa (PL)

(74) Representative: AOMB Polska Sp. z.o.o. 
Ul. Emilii Plater 53 21st Floor
00-113 Warsaw
00-113 Warsaw (PL)

   


(54) A METHOD OF MANUFACTURING AN ACTIVE OPTICAL FIBRE AND THE ACTIVE OPTICAL FIBRE


(57) A method of manufacturing an active optical fibre conducting and generating radiation having a wavelength λ according to the invention includes a step of preparing a core sub-preform of glass doped with an active dopant and a step of drawing the core sub-preform along with a cladding preform. In the step of making the core sub-preform, a structural preform is compiled, said preform containing at least glass rods made of a first type of glass having a first refractive index n1 and glass rods made of a second type of glass having a second refractive index n2. The rods are arranged according to a selected pattern to provide the assumed refractive index profile. The second refractive index n2 is higher than or equal to the highest value of the refractive index profile assumed for the core, and the first refractive index n1 has a value lower than or equal to the lowest value of the assumed refractive index profile in the core cross-section. At least the second type of glass contains at least one active dopant. The structural preform is subjected to thinning by drawing in order to obtain a core preform. Dimensions of the rods and process parameters of the f drawing of the structural preform and the sub-preform of the core with cladding are selected such that the glass rods thinned as a result of drawing, and constituting elongate core elements of the final optical fibre, have transverse dimensions smaller than 1/5 of the wavelength λ.
The active optical fibre according to the invention is adapted to conduct and generate radiation having a wavelength λ. It is provided with a cladding and a core containing at least one active dopant, characterised in that the core comprises elongate elements made of a first type of glass having a first refractive index n1 and elongate elements of a second type of glass having a second refractive index n2, oriented along the optical fibre and forming a compact bundle, wherein transverse dimensions of the elongate core elements are smaller than 1/5 of the wavelength λ.