Made from all electro-optically active components, the S-TNF filter product can be electrically switched between notch blocking and transparent non-blocking states.
S-TNF
The S-TNF™ series filters are one-of-a-kind products - they are switchable & tunable notch filters. Their performance is superior to the competitive products offered in the marketplace - they have 2X higher transmittance over a super-wide spectral range in the non-blocking state. This is critical for capturing images under weak illumination. The filters:
- Feature all active components made from liquid crystal and
- Do not rely on light absorption mechanism
The S-TNF™ products can be used either as system components or standalone devices. Their typical applications include laser protection, spectral filtering, laser beam directing, beam splitting, remote sensing, vision-aids, etc...
The S-TNF™ series has high optical density at the notch wavelength in the active blocking state, > 40% transmittance outside the notch band, and a switching time of ~5 ms.
S-TNF™ enables a sensor
to see a scene under weak
illumination condition
The same sensor has difficulty in
seeing this weak scene with a
commercial tunable notch filter
Sensor is jammed by the
green laser radiation
The sensor is recovered by
the S-TNF™ filter
The S-TNF™ series come with a compact power supply that is either battery or 110/220 V wall-plug powered. Customer options include the selection of spectral range, operational mode (manual or computer control), substrate material, shape and aperture. All products are offered at a competitive price. Contact us for a price quote with your specific application requirements.
Transmission in Blocking State
Non-blocking Transmission (VNIR)
Non-blocking Transmission (SWIR)
S-TNF™ 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 wavelength | > 300 nm (continuously tunable blocking) |
| Tunable narrowband blocking optical density | high over 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 nm (circular) Area: 5 x 5 to 50 x 50 mm2 (square) |
| Thickness | < 10 mm |
| Operating temperature range | -5°C to 55°C without heating mechanism; -40°C to 55° C with heating mechanism |
| Survival temperature range | -51°C to 120°C |
| Laser damage threshhold | > 1 J/cm2 (5 ns pulsed @ 532 nm) > kW/cm2 (CW @ 532 nm) |
| Uniformity of retardance | < 0.1 OD across the clear aperture |
| Wavelength distorsion | < 0.5 wavelength at 633 nm |
| Parallelism | < 2 arcminutes |
| Response time | 5.3 ms switching to blocking mode |
| Rate of change of temperature | Survive 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 - 60Hz AC or 9V battery |
| Total power consumption | < 4W |
| Power supply weight | 200g |