LCPG Principles
Download PDF Fundamentals Liquid crystal polarization gratings (PGs) are fascinating
Beam Steering with Liquid Crystal Polarization Gratings
Click image to enlarge.
Previous
Next
Contact for price
Key Features
- Low size, weight, and power
- Random-access scanning
- Robust non-mechanical operation
- Large apertures possible (>15cm)
- Diffraction-limited wavefront quality
- High diffraction efficiency (>99%)
- Up to 80°×80° steering demonstrated
- Demonstrated in VIS to MWIR
Beam Steering with Liquid Crystal Polarization Gratings
Liquid crystal polarization gratings are also known as geometric phase gratings, Pancharatnam-Berry phase gratings, and diffractive waveplates. These transmissive gratings efficiently (> 99.5%) diffract circularly polarized light to either the first positive or negative order, based on the handedness of the incident light. By incorporating fast electro-optic half-wave polarization retarders to control the handedness of polarization, Meadowlark can develop custom LCPG devices and systems with a range of leading capabilities:
- Wide-angle beam steering > 100°
- Large apertures > 20 cm
- Sub-millisecond switching times
- Dramatically reduced size, weight, and power (SWaP) requirements
- Random-access and inertia-less beam steering
- Dynamic focusing also available
READ MORE
Non-Mechanical Steering for a Range of Aperture Sizes Meadowlark can build LCPGs and LC switches using thin 200 μm glass and with apertures ranging from 2 mm to 200 mm. Thin glass enables discrete steering to >1,000 revolvable angles with transmissive assemblies < 1 cm thick. Meanwhile the ability to steer large beams over large angles makes this approach unique among non-mechanical steering technologies for replacing large gimbals or steering large collection apertures in optical receiver paths.
CPG Steering for Lidar LCPG technology excels at non-mechanical beam steering for many narrowband sensors including lidar. To date, we have demonstrated LCPG beam steering for both coherent and direct detection lidars and both monostatic and bistatic architectures. Due to the ability to steer light in discrete steps over large angles, LCPG beam steering is particularly well suited to steering flash lidar systems and coherent doppler lidar wind sensing systems
Ordering Information – Contact Us for a Quote
| Meadowlark can provide custom systems to meet your needs using the patented liquid crystal polarization grating (LCPG) beam steering technology. When contacting us for a quote, please provide: | •Clear Aperture (mm) •Operating Wavelength (nm) •1D or 2D Steering •Number of Angles •Maximum Steering Angle (°) •Response Time/Switching Speed (ms) •Housing/Mechanical Interface Requirements •Description of Application & Additional Details |
Don’t see what you’re looking for?
We also offer a commercial product line consisting of unmounted LCPGs without integrated anti-reflection (AR) coatings so that we can provide customers with the best price. Please contact our knowledgeable Solutions Engineers regarding custom options, including custom diffraction angles, aperture sizes, and wavelengths through the visible to midwave infrared.
Filters Sort results
Reset Apply
Filters Sort results
Reset Apply
Filters Sort results
Reset Apply
Beam Steering with Liquid Crystal Polarization Gratings
Fundamentals
Liquid crystal polarization gratings (PGs) are fascinating optical components that differ from traditional diffraction gratings, like ruled, Bragg, or holographic gratings. In particular, PGs exhibit polarization sensitivity, can have diffraction efficiency approaching 100%, and are much less sensitive to incident angle than, for example, Bragg or volume holographic gratings. To understand how this is possible, it is important to first understand how PGs work.
Graphs & Figures
These plots show typical zero-order leakage spectra for different LCPG specifications. The LCPG diffraction efficiency is highest where the zero-order leakage is at a minimum.
Previous
Next
Geometric-Phase Microscopy for Quantitative Phase Imaging of Isotropic, Birefringent and Space-Variant Polarization Samples
Geometric-phase microscopy (GPM) uses changes in the phase of light
