Motorola Symbol SE4400, Руководство по интеграции

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SE4400 Integration Guide
Commercially Available Coatings
Anti-Reflection Coatings
Anti-reflection coatings can be used for stray light control or to achieve maximum working
range, and can be applied to the inside and/or outside of the window to reduce the amount
of light reflected off the window back into the engine. However, they are expensive and
have very poor abrasion and scratch resistance.
Polysiloxane Coating
Polysiloxane type coatings are applied to plastic surfaces to improve the surface resistance
to both scratch and abrasion. To apply, dip and air dry in an oven with filtered hot air.
To gauge a window's durability, use ASTM standard D1044, Standard Test Method for
Resistance of Transparent Plastics to Surface Abrasion (the Taber Test), which quantifies
abrasion resistance as a percent increase in haze after a specified number of cycles and
load. Lower values of the increase in haze correspond to better abrasion and scratch
resistance. See
Table 2-2 .
Table 2-2. Taber Test Results on Common Exit Window Materials
Sample Haze 100 cycles Haze 500 cycles Abrasion
Resistance
Chemically Tempered
Float Glass 1.20% 1.50% Best
PMMA with Polysiloxane
Hardcoat 3% 10%
ADC 5% 30%
PMMA 30% Worst
* All measurements use a 100 gram load and CS-10F Abraser.