Laser Line Tunable Filter
The Laser Line Tunable Filter (LLTF CONTRAST) is a non-dispersive patented (US patent 7557990) tunable bandpass filter based on volume Bragg gratings. It combines very high optical density (> OD6), an outstanding out-of-band rejection, and wide tunability. The LLTF can be customized to cover the entire 400 nm to 2500 nm spectral range with a high spectral resolution.
It can be coupled with a wide variety of broadband sources to create a tunable laser source. It can also be used as a cleanup filter for spectroscopy applications.
There are numerous possible LLTF configurations whose spectral range and bandwidth can be finely tuned to fit specific needs. The specifications below of several tried-and-tested standard models may serve as a starting point.
Product Specifications
CONTRAST-SR-VIS | CONTRAST-SR-SWIR | CONTRAST-EXT III | CONTRAST-EXT IV | |
---|---|---|---|---|
Spectral range | 400-1000 nm | 1000-2300 nm (2500 nm optional) | 400-1700 nm | 400-2300 nm (2500 nm optional) |
Bandwidth (FWHM) | 1.5 - 2.5 nm | 2.0 - 5.0 nm | 400-1000 nm: 1.5 - 2.5 nm | 1000-1700 nm: 2.0 - 5.0 nm | 400-1000 nm: 1.5 - 2.5 nm | 1000-2300 nm: 2.0 - 5.0 nm |
Out-of-band rejection | <-60 dB@±40 nm, typically <-30 dB@±10 nm | <-60 dB@±80nm, typically <-30 dB@±20nm | 400-1000 nm: <-60 dB@±40 nm, typically <-30dB@±10 nm | 1000-1700 nm: <-60dB@±80 nm, typically <-30 dB@±20 nm | 400-1000 nm: <-60 dB@±40 nm, typically <-30dB@±10 nm | 1000-2300 nm: <-60dB@±80 nm, typically <-30 dB@±20 nm |
Peak efficiency | Typically around 65% | Typically around 65% | Typically around 65% | Typically around 65% |
Optical density (OD) | > OD6 (measured at 1064 nm) | > OD6 (measured at 1064 nm) | > OD6 (measured at 1064 nm) | > OD6 (measured at 1064 nm) |
Stabilization time/wavelength step | 20 ms < 1 nm; 25 ms / 1 nm; 28 ms / 2 nm; 35 ms / 5 nm; 50 ms / 10 nm | 20 ms < 1 nm; 25 ms / 1 nm; 28 ms / 2 nm; 35 ms / 5 nm; 50 ms / 10 nm | 20 ms < 1 nm; 25 ms / 1 nm; 28 ms / 2 nm; 35 ms / 5 nm; 50 ms / 10 nm | 20 ms < 1 nm; 25 ms / 1 nm; 28 ms / 2 nm; 35 ms / 5 nm; 50 ms / 10 nm |
Dimensions (L x W x H) | 9 x 6.3 x 6.7 (inches), 23 x 16 x 17 (cm) | 9 x 6.3 x 6.7 (inches), 23 x 16 x 17 (cm) | 9 x 6.3 x 6.7 (inches), 23 x 16 x 17 (cm) | 11.8 x 9.1 x 6.7 (inches), 30 x 23 x 17.4 (cm) |
Options & Accessories | ||||
Fibered output | An X-Y-Z translation adjustment allows coupling optimization. FC\APC standard connector (SMA, FC\PC on demand). Both lens and mirror-based models available | An X-Y-Z translation adjustment allows coupling optimization. FC\APC standard connector (SMA, FC\PC on demand). Both lens and mirror-based models available | An X-Y-Z translation adjustment allows coupling optimization. FC\APC standard connector (SMA, FC\PC on demand). Both lens and mirror-based models available | An X-Y-Z translation adjustment allows coupling optimization. FC\APC standard connector (SMA, FC\PC on demand). Both lens and mirror-based models available |
Harmonic filter | Second harmonic suppression included over the 400-500 nm spectral range | Second harmonic suppression included over the 850-1250 nm spectral range. Additional filter for 500-850 nm harmonic suppression available upon request | Second harmonic suppression included over the 400-850 nm spectral range | Second harmonic suppression included over the 400-850 nm spectral range |
Alignement kit | In free space configuration (input/output), the alignment kit allows the user to rapidly find the correct alignment. | In free space configuration (input/output), the alignment kit allows the user to rapidly find the correct alignment. | In free space configuration (input/output), the alignment kit allows the user to rapidly find the correct alignment. | In free space configuration (input/output), the alignment kit allows the user to rapidly find the correct alignment. |
CONTRAST-X | |
Spectral range | X represents a custom spectral range: up to 5 gratings. |
Bandwidth (FWHM) | 0.15 - 0.9 nm |
Out-of-band rejection | Typically -55 dB @± -5 nm |
Peak efficiency | Typically around 65% |
Optical density (OD) | Depends on spectral range |
Stabilization time / wavelength step | 20 ms < 1 nm; 25 ms / 1 nm; 28 ms / 2 nm; 35 ms / 5 nm; 50 ms / 10 nm |
Dimensions (L x W x H) | 9 x 6.3 x 6.7 (inches), 23 x 16 x 17 (cm) |
Options & Accessories | |
Fibered output | An X-Y-Z translation adjustment allows coupling optimization. FC\APC standard connector (SMA, FC\PC on demand). Both lens and mirror based-models available |
Harmonic filter | Upon request |
Alignement kit | In free space configuration (input/output), the alignment kit allows the user to rapidly find the correct alignment. |
Spec Sheet
Publications
Nature Nanotechnology
- Si
Solving integral equations in free space with inverse-designed ultrathin optical metagratings
SPIE Optical Engineering + Applications
- Advanced materials
Comparison of BRDF results from two different scatterometers for instrument validation in support of satellite instrumentation
IOP Science
- Life Sciences
A high-sensitivity rapid acquisition spectrometer for lanthanide(III) luminescence
ECS Transactions
- Other Semiconductors
Ultrabroadband Photoconduction Response of Sub-gap Defects in Amorphous In-Ga-Zn-O Thin Film Transistors
SPIE: Oxide-based Materials and Devices XI.
- Other Semiconductors
Effect of Hydrogen Incorporation on Sub-Gap Density of States in Amorphous Ingazno Thin-Film Transistors
SPIE: Advances in Photonics of Quantum Computing, Memory, and Communication
- Advanced materials
Spectral Properties of Ultra-Broadband Entangled Photons Generated From Chirped-MgSLT Crystal Towards Monocycle Entanglement Generation
Nano Letters
- Carbon-Based Materials
Measurements of the Population Lifetime of D Band and G′ Band Phonons in Single-Walled Carbon Nanotubes
Review of Scientific Instruments
- Advanced materials
- Life Sciences
- Metrology
High Performance Resonance Raman Spectroscopy Using Volume Bragg Gratings As Tunable Light Filters
Videos
Introduction to the Laser Line Tunable Filter - LLTF
The LLTF combines a wide spectral tunability (400-2300 nm) with the highest out-of-band rejection (< -60 dB) available on the market. When coupled to a supercontinuum source, the LLTF is an ideal tool for spectroscopy, calibration and hyperspectral imaging.
OptinaDx Retinal Deep Phenotyping platform™
White Papers
Overview of Laser Line Tunable Filters and Tunable Laser Sources Applications
Authors Laura-Isabelle Dion-Bertrand
Abstract
Widely Tunable Filter: Technology & Measurement of Critical Specifications
Authors Daniel Gagnon and Laura-Isabelle Dion-Bertrand