Thermal camera lenses typically do not have visible color coatings like standard optical lenses because they operate in the infrared spectrum (such as LWIR, MWIR, or SWIR). However, there are variations in coatings and materials that affect their performance, which can give them a different appearance under visible light.
Factors Affecting Thermal Camera Lens Colors
- Anti-Reflective (AR) Coatings
- Applied to improve transmission and reduce reflection in specific infrared wavelengths.
- Can appear blue, purple, gold, or green depending on the coating material and thickness.
- Common coatings: Germanium AR, DLC (Diamond-Like Carbon), High-Durability AR (HDAR).
- Material Used
- Germanium (Ge): Appears black or dark gray.
- Chalcogenide Glass: Can have a brownish or amber hue.
- Zinc Selenide (ZnSe): Yellow-orange in visible light.
- Silicon (Si): Often appears dark with a slight metallic sheen.
- Specialized Filters
- Some lenses may have built-in bandpass filters, appearing in different colors like red, blue, or purple under visible light.
- Filters are used to block specific wavelengths or enhance contrast for thermal imaging applications.
Applications of Colored Thermal Camera Lenses
✅ Industrial & Predictive Maintenance – Enhancing heat detection for machinery and electrical components.
✅ Security & Surveillance – Specialized coatings for low-light performance and durability.
✅ Medical & Scientific Imaging – Infrared coatings optimized for body temperature detection.
✅ Aerospace & Defense – Rugged lenses with anti-reflective coatings to reduce detection by enemy sensors.