1. DS5502 Fixed Mount Scanner Product Reference Guide
  2. Using the Device
  3. Embedded Applications Requiring a Window
  4. Window Material
  • DS5502 Product Reference Guide
Window Material

Window Material

Many window materials that look perfectly clear can contain stresses and distortions that can reduce scanner performance. For this reason, use only cell-cast plastics or optical glass (with or without an anti-reflection coating, depending on the application). Following are descriptions of three popular window materials: PMMA, ADC (CR-39™), and chemically tempered glass. The following table outlines the suggested window properties.
Consider the following window placement and material recommendations if mounting the device within a product with its own window.
Suggested Window Properties
Property
Description
Material
Clear cell-cast acrylic
Spectral Transmission
85% minimum at 400 - 700 nm
Thickness
1.4986 ± 0.127 mm (0.059 ± 0.005 in.)
Wavefront Distortion (transmission)
0.2 wavelengths peak-to-valley maximum over any 2.032 mm (0.08 in.) diameter within the clear aperture
Clear Aperture
To extend to within 1.016 mm (0.04 in.) of the edges all around
Surface Quality
60-20 scratch/dig
Consult an optomechanical engineer to recommend an appropriate window material and to determine if coatings are appropriate for the specific application.
Do not use polycarbonate material.