Windows and filters can occupy the outermost optical position in a lighting or inspection assembly. Because they interact with both the light path and the external environment, optical and mechanical requirements must be considered together.
Protective Windows
Separating Optics From the Environment
A clear window can protect LEDs, lenses, cameras, reflectors, and electronics from dust, debris, moisture, accidental contact, and process residue.
The window should transmit the required wavelengths while remaining mechanically compatible with the housing, seals, fasteners, and cleaning process.
Spectral Control
Optical Filters
Filters can alter the spectral content reaching the target or detector. This can be useful in inspection systems where separating desired light from unwanted ambient wavelengths improves image contrast.
Filter selection should match the light source, camera or sensor, target response, and operating environment.
Surface Reflection
Every Window Adds Optical Interfaces
Light can reflect at transparent surfaces as well as transmit through them. Window angle, surface quality, material, coatings, contamination, and number of interfaces can influence the complete optical result.
Glass Windows
Fabricated Glass Components
Glass fabricators produce cut, shaped, finished, and otherwise processed glass components for industrial applications.
Borosilicate glass is one possible material family where its properties are appropriate to the temperature, mechanical, chemical, and optical requirements.
Polymer Windows
Polycarbonate and Other Transparent Plastics
Transparent polymers can provide lower weight, impact resistance, molded geometry, and manufacturing flexibility in applications where their optical and environmental properties are suitable.
Polycarbonate manufacturers supply material used across a broad range of protective and transparent industrial products.
Sealing
Mounting the Window Into the Housing
Windows can be retained with frames, grooves, gaskets, adhesives, clips, threaded retainers, or other mechanical arrangements.
Retention should control position without placing damaging stress on brittle materials or creating unwanted distortion in optical components.
Inspection
Filters in Machine Vision Systems
In machine vision, the illumination spectrum, target reflectance, optical filter, and camera response can be coordinated to increase separation between the desired feature and background.
Inspection Lighting →Selection