LP980 Longpass Filter (T>85%@990-1100nm, OD2@350-970nm)

Laser Pump Rejection

• Application: Many solid-state lasers and fiber amplifiers (like EDFAs) use a 980 nm laser diode as a "pump" source to excite ions (like Erbium or Ytterbium). This filter is used to block that bright 980 nm excitation light while allowing the longer wavelength fluorescence or lasing signal (e.g., at 1030 nm, 1064 nm, or 1550 nm) to reach the detector.
• Why: Without the filter, the intense 980 nm pump light would saturate or damage the sensor intended to see the weaker emission signal.

Recommended Light Sources

• 980 nm Pump Laser Diode

t acts as the energy source for the system. It emits intense light specifically at 980 nm to "excite" the rare-earth ions (Erbium or Ytterbium) inside the fiber or crystal. This excitation creates the energy required to amplify or generate the longer signal wavelengths (like 1550 nm or 1064 nm).

Deep NIR / SWIR Imaging

Application: Machine vision systems that need to inspect features invisible to the naked eye or standard NIR cameras. By blocking all light up to 970 nm, this filter forces the camera to image only using "deep" infrared light (1000 nm+).

Use Cases: Inspecting semiconductor wafers (silicon becomes transparent >1100 nm, so this is right on the edge), checking moisture content (water absorbs strongly at 1450 nm, but has bands near 970 nm), or specialized surveillance that must remain invisible even to standard 850 nm night-vision cameras.

Recommended Light Sources

• Broadband Tungsten-Halogen Lamps (The Versatile Choice)

Description: These lamps operate by heating a filament, producing a smooth, continuous spectrum of light that spans from visible light all the way out to ~2500 nm.

Why it fits: It naturally provides the high-intensity photons needed for the specific use cases you mentioned:

1. >1100 nm: Required to see through Silicon wafers.
2. 1450 nm: Required to detect water absorption bands.

• High-Power SWIR LEDs (The Targeted Choice)

Description: Unlike standard LEDs, these are engineered (often using InGaAs technology) to emit centered at specific wavelengths like 1050 nm, 1200 nm, 1300 nm, or 1550 nm.

Why it fits:

1. 1050 nm / 1200 nm LEDs: often used for "covert" surveillance or semi-transparent material inspection where you need to be just outside the range of standard silicon sensors.
2. 1550 nm LEDs: Ideal for moisture detection or telecommunications component inspection.