R17 Longpass Filter
Transmit deep red through infrared with sharp edge control and minimal transition ripple.
- Passband: 662 – 780 nm, 90.8 – 95.7 % T (± 2.5 % ripple)
- Cut-on (T50): ≈ 653 nm
- Edge steepness: ~19 nm (10 → 90 % transition)
- Blocking: < 0.96 % T below 629 nm (OD ≥ 2)
- 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, ripple smoothing, 45° AOI, rapid prototypes
Learn more
R17 Hybrid delivers Passband 662 – 780 nm, 90.8 – 95.7 % T (± 2.5 % ripple), Cut-on (T50) ≈ 653 nm, and Edge steepness ~19 nm (10 → 90 % transition).
The hard-oxide coating is built for repeated handling, heat, and cleaning.
Best suited for:
Cy5, Alexa 647, and infrared dye imaging, far-red LED and laser filtering, NIR spectroscopy and photometry, deep color separation in confocal systems, and thermal imaging preparation.
Description
The R17 is the longest-cut-on standard longpass filter in the series, with its 50 % transition at 652.9 nm. It passes wavelengths from 659 nm through 780 nm with average transmission above 94 %, peaking at 95.7 % at the end of the measured range (780 nm). The blocking region holds below 1 % from 380 to 639 nm, averaging just 0.3 %. A mild UV shoulder around 380 nm stays below 5 %. This filter isolates only the deep red and NIR, making it the tightest visible-blocking longpass in the KUPO lineup.
Key Advantages
- 653 nm cut-on for maximum red selectivity - T50 % at 652.9 nm passes only the deep red and NIR - everything from UV through mid-red is blocked.
- OD 2.5+ blocking to 639 nm - Average transmission 0.3 % from 380 to 639 nm provides broad, deep rejection of the visible spectrum.
- 94.8 % average passband - Consistent throughput from 659 to 780 nm with the peak at the NIR end, ideal for combined red/NIR detection.
- Hard-oxide durability - Ion-assisted sputtered coating survives heat, humidity, solvents, and repeated cleaning.
- Custom formats - Round, square, or free-form blanks from 5 mm to 450 mm, thickness 0.21-3.8 mm, on Borofloat, soda-lime, Schott D263 T, or Corning Eagle XG substrates.
Typical Applications
- NIR fluorescence imaging - Collects emission from ICG (indocyanine green), Cy7, and other NIR dyes while blocking all visible excitation light.
- H-alpha astronomy - Passes the 656.3 nm H-alpha line with minimal visible background, ideal for solar and emission nebula observation.
- LIDAR & range-finding - Defines the detection window for 660-780 nm LIDAR systems, rejecting solar and artificial visible background.
- Biomedical NIR window - Isolates the tissue transparency window (> 650 nm) for deep-tissue imaging and photoacoustic applications.
- Covert surveillance - Blocks all visible light while passing NIR illumination for undetectable night-vision systems.
KUPO Optics delivers the R17 to your exact specifications - rapid prototyping and production volumes available. Contact us.
FAQ
R17 FAQ
What is R17 and what is it used for?
R17 is a 655 nm Longpass Filter. The R17 is the longest-cut-on standard longpass filter in the series, with its 50 % transition at 652.9 nm. It passes wavelengths from 659 nm through 780 nm with average transmission above 94 %, peaking at 95.7 % at the end of the measured range (780 nm). Common uses include NIR fluorescence imaging, H-alpha astronomy, LIDAR & range-finding, and Biomedical NIR window.
What are the key optical specs of R17?
Key published specs for R17 include Passband: 662 – 780 nm, 90.8 – 95.7 % T (± 2.5 % ripple); Cut-on (T50): ≈ 653 nm; Edge steepness: ~19 nm (10 → 90 % transition); Blocking: < 0.96 % T below 629 nm (OD ≥ 2); AOI: 0° (normal incidence); custom angles available.
What applications is R17 best suited for?
R17 is commonly used for NIR fluorescence imaging, H-alpha astronomy, LIDAR & range-finding, and Biomedical NIR window. NIR fluorescence imaging - Collects emission from ICG (indocyanine green), Cy7, and other NIR dyes while blocking all visible excitation light.
Can R17 be customized for size, substrate, or coating requirements?
KUPO lists the construction for R17 as Ion-assisted hard-oxide; 5 – 450 mm shapes, 0.21 – 3.8 mm thick. Published custom options include Edge tuning, ripple smoothing, 45° AOI, rapid prototypes. Custom formats - Round, square, or free-form blanks from 5 mm to 450 mm, thickness 0.21-3.8 mm, on Borofloat, soda-lime, Schott D263 T, or Corning Eagle XG substrates.
What should I know about angle of incidence and durability for R17?
The published angle of incidence for R17 is 0° (normal incidence); custom angles available. The hard-oxide coating is built for repeated handling, heat, and cleaning.
