Page 131 - index

EMI shielded window OPTIC Transparent metalized film FMT 15

Electromagnetic interference (EMI) can be described as
any electrical disturbance, whether a signal or noise, which
interferes with electrical equipment’s ability to operate The transparent metalized film (FMT) is a transparent support of low thickness, one of the faces of which is made
correctly. conductive by a metallic deposit.

OPTIC screened windows provide electromagnetic protection This support can be made of polyester or polycarbonate with different surface resistances that influence the
to the front of control screens, measurement indicators and transparency of the material.
displays while still providing good display visibility.
An anti-reflective coating can be applied to the non-conductive face.
Examples of use :
• Military telecommunication radio
• Telecoms bays and cabinet display
• Hardened computer screen

Reference Surface resistivity Ω/□ * Light transmission % **
FMT 15 15 82 ±4%

FMT 8 8 80 ±4%
Shielded windows can be made of glass or polymer, depending on
environmental conditions and desired characteristics. * Surface resistivity tolerance ± 10%
** Values based on a 50 micron polyester sheet
Shielding is provided by a metal micro-mesh placed between the two
transparent panels. The micro-mesh is blackened to maintain optimum
visual performance.

Grounding is provided by a conductive silver busbar placed around the
perimeter of the filter. If required, it can be brought to the front or rear Transmission tolerance ± 4%
surface of the filter. The conductive connection is then made by a conductive
elastomer gasket. Other connection methods are also possible. Attenuations in dB

References 10 KHz 1 MHz 10 MHz 100 MHz 1 GHz
FMT 15 90 84 82 65 37

Number Mesh E-Field attenuation (dB) Plane wave attenuation (dB)
Fine-mesh O.P.I of cells per diameter Transmission
screen (inch²) 1 MHz 10 MHz 100 400 16 Hz 10 GHz (%)
cm² (mm) MHz MHz
70 27 0.08 110 111 98 68 64 38 62
Blackened 100 39 0.03 > 120 > 120 100 67 54 50 81
copper 100 39 0.05 107 111 85 70 58 - 64
145 57 0.05 128 112 106 84 82 64 51

- Anti-reflective coating

- 175 micron ITO polycarbonate
Dimensions and thickness :
OPTIC screened windows are made to customer specifications. Standard thicknesses are 2.5 mm, 3.0 mm,
4 mm and 6 mm. Other thicknesses are available on request.

130
375 Avenue Morane Saulnier 78530 - Buc, France www.getelec.com 131
Tel : +331 39 20 42 42 | info@getelec.com