Glazing having a conductive coating and a data transmission window, method of manufacturing the same and use of the same
The invention concerns a glazing, comprising a pane of glass, a conductive coating on a surface of the pane of glass, a data transmission window in or adjacent the conductive coating, wherein the data transmission window is at least partly coating-free, wherein the data transmission window comprises, a rectangular portion having a shorter edge and a longer edge; and a protrusion from the shorter edge or the longer edge, wherein the protrusion comprises an axial portion having an axis parallel with the longer edge. A method for manufacturing the glazing and use of the glazing for example as window of a motor vehicle is also claimed. The invention is suitable for radio frequency identification transponders operating for example in the UHF frequency band.
1 . A glazing, comprising:
a pane of glass;
a conductive coating on a surface of the pane of glass;
a data transmission window in or adjacent the conductive coating;
wherein the data transmission window is at least partly coating-free;
wherein the data transmission window comprises:
a rectangular portion having a shorter edge and a longer edge; and
a protrusion from the shorter edge or the longer edge;
wherein the protrusion comprises:
an axial portion having an axis parallel with the longer edge; and
wherein the protrusion and the axial portion are coating-free; and
wherein the rectangular portion comprises a plurality of horizontal coating-free lines having a spacing and a plurality of vertical coating-free lines having the same spacing to form a plurality of coated squares or a different spacing to form a plurality of coated rectangles; and
wherein the spacing is chosen to allow transmission at a predetermined frequency through the data transmission window; and
wherein the spacing is less than or equal to one tenth of a wavelength corresponding to the predetermined frequency multiplied by a shortening factor for the pane of glass; and
at least a section of the axial portion having a predetermined length greater than or equal to one sixth of a wavelength of the predetermined frequency multiplied by a shortening factor for the pane of glass.
2 . A glazing according to claim 1 , comprising a plurality of protrusions.
3 . A glazing according to claim 1 , wherein the protrusion has a shape selected from rectangular, triangular, arcuate, linear, bent line, straight line or combinations thereof.
4 . A glazing according to claim 2 , wherein at least one of the protrusions comprises a plurality of axial portions each having an axis parallel with the longer edge.
5 . A glazing according to claim 4 , wherein at least one of the axial portions is shaped as a straight line.
6 . A glazing according to claim 1 , wherein the axial portion has a width in a range from 10 μm to 5 mm.
7 . A glazing according to claim 1 , wherein the axial portion has a length in a range from 10 to 50 mm.
8 . A glazing according to claim 1 , wherein the conductive coating comprises a layer of a transparent conductive oxide.
9 . A glazing according to claim 1 , wherein the conductive coating has sheet resistance less than 325 ohms/square.
10 . A glazing according to claim 1 , further comprising an RFID transponder comprising a control unit for communication with an external device, the control unit comprising a memory for storing identification data.
11 . A glazing according to claim 1 , wherein the predetermined length is less than or equal to one half of a wavelength of the predetermined frequency multiplied by a shortening factor for the pane of glass.
12 . Use of the glazing according to claim 1 as a windshield, a rear window, a side window, or a roof window of a motor vehicle or as a for a building, or a window in a refrigerator door, or in street furniture.
13 . A glazing according to claim 1 , wherein the axial portion has a width in a range from 30 μm to 200 μm.
14 . A glazing according to claim 1 , wherein the axial portion has a length in a range from 25 to 35 mm.
15 . A glazing according to claim 1 , wherein the conductive coating comprises a layer of a doped transparent conductive oxide.
16 . A glazing according to claim 1 , wherein the conductive coating has sheet resistance less than 7 ohms/square.
17 . A glazing according to claim 1 , wherein the axial portion is shaped as a straight line.
18 . A method for manufacturing a glazing, comprising:
providing a pane of glass;
depositing a conductive coating on a surface of the pane of glass;
forming a data transmission window in or adjacent the conductive coating;
wherein the data transmission window is at least partly coating-free;
wherein the data transmission window comprises:
a rectangular portion having a shorter edge and a longer edge; and
a protrusion from the shorter edge or the longer edge;
wherein the protrusion comprises:
an axial portion having an axis parallel with the longer edge; and
wherein the protrusion and the axial portion are coating-free; and
wherein the rectangular portion comprises a plurality of horizontal coating-free lines having a spacing and a plurality of vertical coating-free lines having the same spacing to form a plurality of coated squares or a different spacing to form a plurality of coated rectangles; and
wherein the spacing is chosen to allow transmission at a predetermined frequency through the data transmission window; and
wherein the spacing is less than or equal to one tenth of a wavelength corresponding to the predetermined frequency multiplied by a shortening factor for the pane of glass; and
at least a section of the axial portion having a predetermined length greater than or equal to one sixth of a wavelength of the predetermined frequency multiplied by a shortening factor for the pane of glass.
19 . A method for manufacturing a glazing according to claim 18 , further comprising pyrolytically depositing the conductive coating during manufacture of the pane of glass.
20 . A method for manufacturing a glazing according to claim 18 , further comprising forming the data transmission window at least partly by laser deletion of the conductive coating.