R2613 Longpass Filter
Long-pass filter blocking green-cyan (< 595 nm) while passing 92–94 % rich red light (625 – 770 nm) for warm, glare-free output.
- Red passband: 625 – 770 nm, 92 – 94 % T (± 2 % ripple)
- Cut-on (T50): ≈ 610 nm
- Edge steepness: ~15 nm (10 → 90 % transition)
- Blue-green blocking: < 1 % T below 595 nm
- 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
R2613 keeps transmission below one percent all the way to ~595 nm, reaches the 50 % point near 610 nm, clears 90 % by ~625 nm, and then rides a 92–94 % plateau past 770 nm with ripple limited to ± 2 %. The ion-assisted hard-oxide coating withstands heat, humidity, solvents, and repeated cleaning. KUPO can supply Borofloat®, soda-lime, Schott D263 T, or Corning Eagle XG substrates in any outline—from 5 mm chips to 450 mm plates, 0.21 – 3.8 mm thick—and ship prototypes in about two weeks.
Typical uses: LED colour tuning, far-red fluorescence collection, green-glare suppression in machine vision, daylight-to-tungsten warming for film lighting, and AR/HUD graphics injection without blue-green bleed.
Description
R2613 keeps transmission below 1 % all the way to about 595 nm, reaches the 50 % point near 610 nm, clears 90 % by roughly 625 nm, and then tracks a 92–94 % plateau through at least 770 nm with spectral ripple limited to about ±2 %. The curve is engineered for jobs that need clean red light—warming LED fixtures, capturing red-emission fluorescence, or removing green glare from machine-vision cameras—without resorting to gels or multiple optics.
Key advantages
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Sharp green-cyan cutoff – 50 % cut-on ≈ 610 nm; < 1 % T maintained through ~595 nm to minimise blue/green leakage.
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High, flat red passband – 92–94 % T from ~625 nm to 770 nm keeps brightness and hue consistent.
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Hard-oxide durability – Ion-assisted layers shrug off heat, humidity, solvents, and repeated cleanings.
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Flexible formats – Round, square, or custom blanks from 5 mm to 450 mm, 0.21–3.8 mm thick, on Borofloat®, soda-lime, Schott D263 T, or Corning Eagle XG glass.
Typical applications
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LED colour tuning – Remove cool spikes in white or RGB fixtures for warm, red-rich ambience.
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Fluorescence emission – Collect far-red probes (Cy5, Alexa Fluor 647) while blocking shorter-wavelength excitation lines.
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Machine vision – Strip green reflections from reflective parts while keeping the red channel bright for defect detection.
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Photography & cinema – Warm daylight LED panels toward a tungsten look without gels or significant light loss.
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AR / HUD optics – Inject red graphics cleanly, with negligible blue-green bleed toward the viewer.
Need a rapid prototype or a high-volume run? R2613 filters can be coated, diced, and shipped to your exact specifications—quickly and reliably.
