The B-NF series is an optically binned switchable notch filter made from Kent Optronics fast speed liquid crystal materials.
The B-NF series is an optically binned switchable notch filter made from Kent Optronics’ fast speed liquid crystal materials. Each B-NF filter consists of ≥2 filter bins to cover a broad spectral region (e.g., > 100 nm from the visible to infrared) for light blocking or routing. Each individual filter bin has a customized notch bandwidth. The filter can be rapidly switched between the transparent and reflection states.
The product series offers customers with an E-O component for purpose as an agile laser beam director, laser blocker, beam splitter, etc…, in the envisioned photonics systems, such as laser protection devices, remote sensing, vision-aid devices, and broadband light routing.
As compared to the state-of-the-art tunable notch filters containing passive polarizers, the B-NF series offers the following un-matchable performance specifications:
- 2X lower insertion loss in transparent state
- high optical density (OD) at the notch wavelength
- >80% out band transmittance
- ≤20 ms switching speed
The product comes with a compact power supply that can be either battery or 110/220 V wall-plug powered. Customers have the options to choose the filter substrate material, shape, aperture and the operation mode (i.e., manual or computer controlled). All products are offered at a competitive price. Contact us for a price quote with your specific application requirements.
The following is an exemplary 3-binned B-NF filter in the near IR.
Reflection State
Reflection State
Reflection State
B-NF™ Specifications
| Spectral region | 0.4-2.7 µm |
| Transmittance (blocking inactive) | ~80% |
| Scene spectral neutrality (blocking inactive) | Neutral |
| Polarizing properties | Polarization insensitive |
| Tunable narrowband blocking waveband | >300 nm (continuously tunable blocking) |
| Tunable narrowband blocking optical density | OD>3 over the bandwidth |
| Angular range for broadband transmission (parallel light operation) | >25° in air |
| Angular range for tunable narrowband blocking (parallel light operation) | >25° in air |
| Clear aperture | Diameter: 5-50 mm (circular) Area: 5×5 to 50×50 mm² (square) |
| Thickness | <10 mm |
| Operating temperature range | -5°C (23°F) to 55°C (131°F) without heating mechanism; -40°C (-40°F) to 55°C (131°F) with heating mechanism |
| Survival temperature range | -51°C (-59.8°F) to 120°C (248°F) |
| Laser damage threshold | >1 J/cm² (5ns pulsed @ 532nm) >1 kW/cm² (CW @ 532nm) |
| Uniformity of retardance | <0.1 OD across the clear aperture |
| Wavefront distortion | <0.5 wavelength at 633nm |
| Parallelism | <2 arcminutes |
| Response time | 5.3 ms switching to blocking mode |
| Rate of change of temperature | Survives a rate of change of temperature of 3°C per minute |
| Driving voltage | Polarizer: 280V RMS Retarder: 0-1.5V RMS |
| Computer interface | USB interface w/PC |
| Weight | <100g (filter only) |
| Substrate material | Glass, quartz, and plastic (PC) |
| Cable length | 1 m |
| Input power to the driver | 110V or 220V/50-60 Hz AC or 9V battery |
| Total power consumption | <4W |
| Power supply weight | 200g |