1064nm Bandpass Filters

LIDAR (Light Detection and Ranging)

Used in receiver optics to filter out sunlight and background radiation, allowing only the 1064 nm return signal from the laser to be detected.

Recommended Light Sources

For this specific LIDAR application, where the receiver is filtering for a 1064 nm return signal, the recommended light source is a Pulsed Nd:YAG Laser (Neodymium-doped Yttrium Aluminum Garnet).

A Ytterbium (Yb) Doped Fiber Laser is also a strong candidate, as it can be tuned to 1064 nm and offers high beam quality for precision scanning.

Laser Line Cleanup

Used directly in front of a laser source to remove "spectral noise," such as spontaneous emission or secondary harmonics, ensuring the output is a pure 1064 nm beam.

Recommended Light Sources

The specific center wavelength of 1064 nm dictates the light sources. You should use this filter with:

• Nd:YAG Lasers: The most common source. These solid-state lasers emit naturally at 1064.1 nm.
• Yb-Doped Fiber Lasers (Ytterbium): These can be tuned or designed to emit at 1064 nm.
• Nd:YVO4 Lasers: Another crystal laser variant similar to YAG, emitting at 1064 nm.
• 1064 nm Laser Diodes: Semiconductor lasers manufactured specifically for this wavelength, often used in telecom or pumping applications.

Material Sorting

Identifying different types of plastics in recycling streams, as many plastics have unique absorption bands in this range.

Recommended Light Sources

• Tungsten-Halogen (Broadband)

Incident Light: Hits the mixed stream of plastics.

Interaction:

1. Clear/Colored Plastics: Reflect the 1064 nm light (appear bright).
2. Black Plastics: Absorb the 1064 nm light (appear dark).

Detection: The BP1064-100 filters out all visible light and "noise" from the factory environment, ensuring the camera only sees this high-contrast IR signal.

Moisture Detection

Water absorbs light strongly around 1450 nm but has distinct contrast features at 1064 nm compared to dry materials.

Recommended Light Sources

For moisture detection using the BP1064-100 filter, the recommended light sources fall into two main categories depending on whether you need a dedicated 1064 nm signal or a multi-spectral setup that might also utilize the 1450 nm band later.

• Broadband Sources (Halogen or Tungsten)

This is often the most practical choice for moisture detection research or multi-band systems.

Why it works: Halogen bulbs emit a massive amount of "near-infrared" energy, covering both the 1064 nm (reference/contrast) and 1450 nm (water absorption) bands simultaneously.

Benefit: You can use a single light source and simply swap filters (or use a multi-sensor camera) to see both the "dry" reference image and the "wet" absorption image without changing illumination.

• High-Power IR LEDs (1050 nm - 1060 nm)

Why it works: These LEDs are tuned to emit specifically within the passband of your BP1064 filter.

Benefit: They are much cooler and more energy-efficient than halogen lamps. Because they don't waste energy emitting visible light or heat (wavelengths >1500 nm) that you would filter out anyway, they reduce thermal noise in the system.

• Nd:YAG Lasers (1064 nm)

Why it works: Provides an extremely intense, coherent beam at exactly 1064 nm.

Benefit: Best for high-speed conveyor belts or long-distance detection where you need maximum signal strength to "freeze" the motion of moving products.

Specification

• Center Wavelength (CWL): 1064 nm (This is a standard laser line).
• Bandwidth (FWHM): 20 nm (The filter allows light from ~1054 nm to 1074 nm to pass).
• Blocking (OD4): Optical Density 4 means it blocks 99.99% of unwanted light across the 200–1200 nm range (UV, Visible, and NIR), except for the 1064 nm passband.
• Transmission (T=80%): It allows 80% of the target 1064 nm light to pass through, which is a high efficiency for a narrow band filter.

Application - Industrial Laser Monitoring

Used in sensors that monitor the welding or cutting process of a high-power fiber laser to protect the sensor from the bright visible sparks (plasma) while detecting the reflected laser light.

Recommended Light Source

For Industrial Laser Monitoring using a BP1064-20 Bandpass Filter, the "light source" is actually the High-Power Processing Laser itself.

Here is the breakdown of why this specific source is used and how it functions in the setup:

• High-Power Ytterbium Fiber Laser or Nd:YAG Laser.

These lasers are used to cut or weld the metal.They must emit at approximately 1064 nm (matching your filter's passband).

How it Works:

1. - Instead of adding a separate light to "see" the weld, the sensor detects the reflection of the cutting laser beam bouncing off the metal surface.
2. - The Signal: The intensity and stability of this reflected 1064 nm light provide real-time data on the weld quality (e.g., if the focus is correct or if the weld has penetrated the material).

• Role of the Filter: The welding process creates a bright, white-hot spark (plasma) that emits light across the entire spectrum. The BP1064-20 filter blocks this blinding visible plasma light but allows the specific 1064 nm reflected laser light to pass through to the sensor, ensuring a clean signal.

Specification

• Center Wavelength (CWL): 1064 nm (This is a standard laser line).
• Bandwidth (FWHM): 20 nm (The filter allows light from ~1054 nm to 1074 nm to pass).
• Blocking (OD4): Optical Density 4 means it blocks 99.99% of unwanted light across the 200–1200 nm range (UV, Visible, and NIR), except for the 1064 nm passband.
• Transmission (T=80%): It allows 80% of the target 1064 nm light to pass through, which is a high efficiency for a narrow band filter.

Application - LIDAR & Rangefinding

1064 nm is a standard wavelength for high-power LIDAR (Light Detection and Ranging) used in topography and autonomous vehicles. The filter prevents solar noise from interfering with the return signal.

Recommended Light Source

For LIDAR and rangefinding applications using a 1064 nm bandpass filter, the recommended light source is a Pulsed Nd:YAG Laser.

Here is a brief description of why it is the standard choice:

• Precise Wavelength Match: The Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) crystal naturally emits light at exactly 1064 nm, matching the center wavelength of your filter perfectly.
• High Pulse Power: These lasers can generate extremely high-energy pulses (Q-switching). High peak power is essential for LIDAR to ensure the signal can travel long distances to a target (like a mountain or a car) and reflect back to the sensor.
• Invisible Beam: The 1064 nm output is invisible to the human eye, which is critical for safety and non-intrusive operation in autonomous vehicles or topographic scanning.

Specification

While "BP1064-35" is a model number format used by various optical manufacturers (such as OptoSigma, MidOpt, or MOK Optics), the code itself decodes into specific optical parameters:

• BP: Bandpass Filter.
• 1064: Center Wavelength (CWL) of 1064 nm (Near-Infrared / NIR).
• 35: Full Width at Half Maximum (FWHM) of 35 nm. This means the filter passes light primarily between ~1046.5 nm and 1081.5 nm.
• T=90%: High transmission rate (>90%) within the passband, ensuring minimal signal loss.
• OD4 @ 200–1200nm: This indicates an Optical Density of 4 (blocking 99.99% of light) across the 200–1200 nm range, excluding the passband. This is a critical feature: it effectively "blinds" the sensor to all UV, Visible, and non-relevant IR light, allowing only the 1064 nm signal to pass.

Application - Active Night Vision & Surveillance

In security systems that use 1064 nm active illumination, this filter is placed over the camera lens. Since 1064 nm is invisible to the human eye (and shows no "red glow" like 850 nm LEDs), it allows for covert surveillance. The filter removes visible light, ensuring the image remains clear even if car headlights or streetlights are in the frame.

Recommended Light Sources

• High-Power 1064 nm IR Laser Illuminators (Primary Choice)

For active surveillance, laser-based illuminators are the standard choice at this wavelength.

Why they are used: Standard silicon camera sensors have low sensitivity at 1064 nm. To compensate, you need a light source with high intensity and long throw capabilities, which lasers provide much better than LEDs.

Key Advantage: They emit a coherent beam that can be shaped (narrow for long-range, wide for area monitoring) without the "red glow" associated with standard IR LEDs.

• High-Power 1064 nm LED Arrays

For shorter-range indoor or machine vision applications, specialized LED arrays are available.

Why they are used: They are generally safer (non-coherent light) and cheaper than laser illuminators.

Limitation: They have a broader spectral bandwidth. You must ensure the LED's output does not drift outside your filter's 35 nm passband (1046–1081 nm), or you will lose illumination power.

Specification

While "BP1064-35" is a model number format used by various optical manufacturers (such as OptoSigma, MidOpt, or MOK Optics), the code itself decodes into specific optical parameters:

• BP: Bandpass Filter.
• 1064: Center Wavelength (CWL) of 1064 nm (Near-Infrared / NIR).
• 35: Full Width at Half Maximum (FWHM) of 35 nm. This means the filter passes light primarily between ~1046.5 nm and 1081.5 nm.
• T=90%: High transmission rate (>90%) within the passband, ensuring minimal signal loss.
• OD4 @ 200–1200nm: This indicates an Optical Density of 4 (blocking 99.99% of light) across the 200–1200 nm range, excluding the passband. This is a critical feature: it effectively "blinds" the sensor to all UV, Visible, and non-relevant IR light, allowing only the 1064 nm signal to pass.

Applications - Laser Systems (Nd:YAG)

1064 nm is the fundamental wavelength of Nd:YAG lasers. This filter is used in laser designating, rangefinding, or receiving systems to prevent the detector from being saturated by background light.

Recommended Light Sources

To utilize this filter effectively, you must use a light source that emits energy specifically within the filter's 1046–1081 nm passband.

• Nd:YAG Lasers (1064 nm): The most common match. These are used for cutting, welding, marking, and medical procedures.
• 1064 nm Laser Diodes: Compact semiconductor lasers used in telecommunications, LIDAR, and sensing.
• High-Power IR LEDs (1050 nm - 1070 nm): While less monochromatic than lasers, high-power infrared LEDs centered near 1060 nm are often used for machine vision and surveillance illumination. Note: Standard 850 nm or 940 nm IR LEDs will not work, as this filter will block their light (OD4).
• Fiber Lasers (Ytterbium-doped): These lasers typically operate between 1030 nm and 1100 nm. The 35 nm bandwidth of your filter is wide enough to capture the output of many standard fiber lasers operating near 1064 nm.