Linear Variable VIS NIR Bandpass Filters For Hyperspectral Imaging
Hyperspectral imaging (HSI) is used for many applications including satellite imaging and air reconnaissance. HSI is usually executed with bulky hyperspectral-imaging cameras that are sensitive to misalignment, very expensive, and use prisms or gratings as dispersive elements. An alternative method of HSI is the combination of linear variable bandpass filters (LVBPFs) with silicon detectors. This allows for very compact, robust, and affordable HSI detectors that offer several advantages over conventional approaches.
Custom linear variable bandpass filter designs are available. Filters with the following specifications are available for immediate testing:
LV VIS NIR Bandpass Filter LF103252
- Center wavelength range of 450 to 880 nm
- Bandwidth approximately 2% of center wavelength
- Transmission 60% to 90%
- Blocking range from 200 to 1150 nm
- Blocking level OD4
- For sensor size 24 x 36 mm
LV VIS NIR Bandpass Filter LF103245
- Center wavelength range of 450 to 850 nm
- Bandwidth approximately 4% of center wavelength
- Transmission 70% to 90%
- Blocking range from 200 to 1100 nm
- Blocking level OD4
- For sensor size 25 x 25 mm
Delta Optical also offers a wedged Continuously Variable Filters (CVF), whose spectral properties vary continuously along one dimension of the filter. A single CVF can replace a number of fixed filters in an instrument. It is possible to adjust the center or edge wavelength by sliding the filter.
For more information on the LF103252 and LF103245 variable bandpass filters, download the respective datasheets above.