Two Dimensional Volume Conserving Extratorless Non-Linear Wedge (NLW) Light Guide Panels For BLU and FID
Another World's First From Visus!
Key Advantages:
- No need for distributed micro-extractors.
- Available in any size and aspect ratio
- Greatly Reduced NRE & Production costs.
- Higher Yield & Repeatability.
- Up to 1.75 times higher luminance at a given thickness.
- Up to 70% lower Weight & Volume.
Fig. 1. Non-Linear 1D Wedge (NLW) LGP produces uniform luminance without any light Extractors. It is also 25 – 50% lighter compared to planar and linear-wedge LGPs.
Uniform light extraction can be effected by accurate control of LGP’s tilt, i.e. curvature. Obviously this method has key practical benefits compared to conventional distributed micro-extractors. However a complexity of calculating such a surface has been a major hurdle preventing its practical use. Indeed special flux transfer computational methods and lens synthesis software had to be developed to solve the problem.
Two-dimensional non-linear wedge LGP has a generally smooth concave shape and is thinnest at one point (resembling an aspherical concave or plano-concave lens). Since generally X and Y dimensions are not equal and lamps generally are coupled only to some of the edges the wedge has no axial symmetry. It represents a special and unique optical element (system) which can be termed Aspherical Asymmetrical Edge Lens (AAEL). If the lamps are disposed symmetrically about the edges of the polygonal plate, the thinnest point will be at the center; most of the forward propagating flux from each individual lamp toward the center is then incident on a concave surface with negative slope and is gradually extracted out. This surface has a key volume conserving property: a concave shape minimizes to a theoretical limit the volume and thus the weight, of the plate (consistent with the edge width necessary to efficiently couple light from adjacent lamps).
Fig. 2. Two sided Non-Linear 1D Wedge with two CCFLs coupled to opposite edges.
Fig. 3. Four sided Non-Linear 2D Wedge. LEDs are mounted along all four edges. It has 3.5 times higher luminance and is 50-75% lighter compared to one sided planar LGP. For the same luminance thermal management is much better, since a given number of LEDs is mounted more uniformly along all edges.
Fig. 4. Two sided Non-Linear 2D Wedge. LEDs are mounted along two edges. It has 1.75 times higher luminance and is 50-75% lighter compared to one sided planar LGP