Technical Details of NIR Cut Filters
SCHOTT’s team of experts have packed their NIR cut filters full of exceptional features and qualities, including corrosion-beating coatings, first-rate transmission levels, and impressive NIR absorption.
High humidity resistance
BG47, BG59, BG60, BG61, BG62, BG66, BG67SCHOTT’s new IR filter glasses have been designed to perform in difficult environments. Equipped with a special coating, these filters remain completely transparent for more than 1,000 hours without any surface corrosion, delivering extraordinary image quality.
NIR cut filters at different thicknesses
BG47 | BG59 | BG60 | BG61 | BG62 | BG66 | BG67 | ||
---|---|---|---|---|---|---|---|---|
Refractive index | ne | 1.5420 | 1.5547 | 1.5399 | 1.5370 | 1.5417 | 1.5430 | 1.5427 |
nd | 1.5405 | 1.5523 | 1.5379 | 1.5350 | 1.5397 | 1.5388 | 1.5405 | |
Cutoff wavelength λ0.5 | 633 nm | 634 nm | 633 nm | 648 nm | 644 nm | 635 nm | 632 nm | |
At thickness | 0.2 mm | 0.11 mm | 0.3 mm | 0.3 mm | 0.21 mm | 0.21 mm | 0.175 mm |
High steepness of NIR cut
BG18, BG38, BG39, BG40, BG42, BG55, S8612These glasses provide a number of excellent optical properties, including high transmission and blocking with a very narrow transition range. They are also ideal bandpass filters for visual areas when high absorption in the near infrared (NIR) wavelength range is required. The slope of the IR edge is exceptional and guarantees a sharp distinction between visible light and NIR radiation.
NIR cut filters at different thicknesses
BG18 | BG38 | BG39 | BG40 | BG42 | BG55 | S8612 | ||
---|---|---|---|---|---|---|---|---|
Refractive index | ne | 1.5358 | 1.5291 | 1.5383 | 1.5320 | 1.5419 | 1.5418 | 1.5422 |
nd | 1.5340 | 1.5272 | 1.5363 | 1.5300 | 1.5400 | 1.5398 | 1.5402 | |
Cutoff wavelength λ0.5 | 595 nm | 646 nm | 603 nm | 635 nm | 595 nm | 596 nm | 599 nm | |
At thickness | 1 mm |
NVIS-compatible
S8022, S8023, VG20NVIS-compatible glasses have an exceptional strong blocking for wavelengths above 630 nm. This makes them the perfect filter for displays and controls that are compatible with night vision googles (NVIS equipment). The filters enable the observer to recognize the correct colors of the displays and controls in aircraft cockpits.
The glasses S8022 and S8023 are optimized for NVIS Green A, while VG20 has been designed for NVIS white for LED light sources.
Comparison of NIR cut filters at different thicknesses
S8022 | S8023 | VG20 | ||
---|---|---|---|---|
Refractive index | ne | 1.5595 | 1.5437 | 1.5427 |
nd | 1.5550 | 1.5410 | 1.5405 | |
Cutoff wavelength λ0.5 | 533 nm | 565 nm | 562 nm | |
At thickness | 1 mm | |||
NVIS Green A at Planck illumination (1550 K - 3200 K) |
NVIS White at neutral and warm white LED light |