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clear and has even refraction. It is suggested to use PMMA or optical glass with transmission rate over
90% and vagueness rate less than 1%. Whether coated or not depends on materials and application
demands.
Abrasion-resistant and Coating
Scratch on window will severely reduce the reading performance. It is suggested to use high-abrasion
window material or use abrasion-resistant coating to prevent scratch and abrasion.
Window Size
The primary requirement for window design is to ensure the window will not obstruct the field of view.
Based on that, the less obstruction on illumination envelope the better. Window size diagrams are shown
below for design reference.
Window Size Diagram
Figure 2-3 Crosswise Section
