CM-900 Cold Mirror & Longpass Filter
Block visible light and near-infrared; pass only short-wave infrared for selective thermal and spectroscopic analysis.
- Reflection band (visible): 380 – 750 nm, ≥ 96.2 % R
- Passband (IR): 908 – 1192 nm, 80.2 – 96.4 % T
- Cut-on (T50): ≈ 899 nm
- Edge steepness: ~32 nm (10 → 90 % transition)
- Visible leakage: < 3.8 % T across 380 – 750 nm
- AOI: 0° (normal incidence); custom angles available
- Construction: Ion-assisted hard-oxide; 5 – 450 mm shapes, 0.21 – 3.8 mm thick
- Custom options: Edge tuning, extended reflection band, custom AOI, rapid prototypes
Learn more
CM-900 Hybrid delivers Reflection band (visible) 380 – 750 nm, ≥ 96.2 % R, Passband (IR) 908 – 1192 nm, 80.2 – 96.4 % T, and Cut-on (T50) ≈ 899 nm.
The hard-oxide coating is built for repeated handling, heat, and cleaning.
Best suited for:
Block visible light and near-infrared; pass only short-wave infrared for selective thermal and spectroscopic analysis.
Description
The CM-900 represents the longest cut-on point in the cold-mirror series at 899 nm, creating an aggressive blocking profile that isolates the deepest infrared signals. Peak transmission reaches 96.4 % at 1056 nm with a 50 % cut-on precisely at 899 nm. Visible extinction is near-total (UV 0.1 %, blue 0.5 %, green 0.9 %, yellow 1.0 %, red 1.2 %), while the entire near-infrared (700-850 nm) is virtually eliminated at 1.0 % transmission. The critical transition occurs in NIR (850-1000 nm) at 66.1 %, then climbs steeply to 92.9 % in SWIR (1000-1200 nm). This extreme-edge filter is engineered for applications demanding absolute separation of 900 nm+ deep-infrared from all ambient and thermal noise below.
Key Advantages
- Ultra-Aggressive Visible-NIR Blocking - Transmits only 1.0 % of NIR (700-850 nm) and 66.1 % of NIR (850-1000 nm), creating the sharpest cutoff in the series for maximum stray-light rejection
- SWIR-Optimized Performance - 92.9 % SWIR transmission above 900 nm isolates the deepest thermal signatures with minimal optical loss or background interference
- Solar-Blind Operation - Blocks the vast majority of ambient solar radiation and visible-light scatter, enabling daylight-compatible deep-IR detection
- Hard-Oxide Ion-Assisted Durability - Premium coating resists thermal gradients, environmental contamination, and mechanical stress in extreme field and laboratory conditions
- Specialized Custom Formats - Manufactured in round, square, and free-form apertures from 5 mm to 450 mm with 0.21-3.8 mm thickness on Borofloat, soda-lime, Schott D263 T, or Corning Eagle XG
Typical Applications
- Deep-SWIR Scientific Spectroscopy - Isolates 1000-1200 nm molecular and thermal signatures in atmospheric chemistry, materials analysis, and combustion diagnostics
- Night-Vision Free-Space Optics - Enables secure, solar-blind communication and imaging by transmitting only deepest-IR channels unavailable to conventional visible-band systems
- High-Altitude Thermal Reconnaissance - Rejects solar interference and visible-light background, enabling thermal imaging and temperature mapping from aircraft and satellites
- Quantum-Cascade Laser Applications - Passes QCL mid-infrared output (1000-1300 nm range) while blocking visible alignment beams and thermal background
- Emerging Hyperspectral SWIR Sensing - Feeds next-generation spectral imaging systems with pure deep-IR data for precision agriculture, mineral identification, and environmental monitoring
The CM-900 is built for cutting-edge deep-IR and SWIR applications at the frontier of thermal sensing. We specialize in rapid prototyping of complex specifications and scaling to production volumes without performance compromise.
FAQ
CM-900 FAQ
What is CM-900 and what is it used for?
CM-900 is a Ultra-Extended Cutoff Cold Mirror for SWIR-Exclusive Deep-Infrared Sensing and Thermal-Only Isolation. The CM-900 represents the longest cut-on point in the cold-mirror series at 899 nm, creating an aggressive blocking profile that isolates the deepest infrared signals. Peak transmission reaches 96.4 % at 1056 nm with a 50 % cut-on precisely at 899 nm. Common uses include Deep-SWIR Scientific Spectroscopy, Night-Vision Free-Space Optics, High-Altitude Thermal Reconnaissance, and Quantum-Cascade Laser Applications.
What are the key optical specs of CM-900?
Key published specs for CM-900 include Reflection band (visible): 380 – 750 nm, ≥ 96.2 % R; Passband (IR): 908 – 1192 nm, 80.2 – 96.4 % T; Cut-on (T50): ≈ 899 nm; Edge steepness: ~32 nm (10 → 90 % transition); Visible leakage: < 3.8 % T across 380 – 750 nm.
What applications is CM-900 best suited for?
CM-900 is commonly used for Deep-SWIR Scientific Spectroscopy, Night-Vision Free-Space Optics, High-Altitude Thermal Reconnaissance, and Quantum-Cascade Laser Applications. Deep-SWIR Scientific Spectroscopy - Isolates 1000-1200 nm molecular and thermal signatures in atmospheric chemistry, materials analysis, and combustion diagnostics.
Can CM-900 be customized for size, substrate, or coating requirements?
KUPO lists the construction for CM-900 as Ion-assisted hard-oxide; 5 – 450 mm shapes, 0.21 – 3.8 mm thick. Published custom options include Edge tuning, extended reflection band, custom AOI, rapid prototypes. SWIR-Optimized Performance - 92.9 % SWIR transmission above 900 nm isolates the deepest thermal signatures with minimal optical loss or background interference.
What should I know about angle of incidence and durability for CM-900?
The published angle of incidence for CM-900 is 0° (normal incidence); custom angles available. The hard-oxide coating is built for repeated handling, heat, and cleaning.
