United Lens Company’s optical witness samples are ideal to use as test pieces for a variety of environmental testing requirements and measuring coatings for spectral performance. They are a cost-effective, high quality choice, made in America at an affordable price. We manufacture witness samples in a variety of 185+ materials, making it a conveniently available choice when the same material type is required for your test piece as your finished substrate. Characteristics of our witness samples include:

• Laser Etched Part Number: Each witness sample has its ULC part number laser etched on the outer diameter for traceability and material type identification.
• Inspected per MIL-PRF-13830B: All samples are inspected for surface quality compliance.