Table 2.
Comparison of different AR combiners
| Combiner efficiency | FoV (diagonal) | Eyebox | Form factor | Major challenge | |
|---|---|---|---|---|---|
| Geometric optics | ~4000 nit/lm | 50°–120°158 | ~8 mm158 | Large | Shrinking size, etendue conservation |
| Maxwellian-type |
~50000 nit/lm (pupil st.) ~3000 nit/lm (pupil dup.) |
~100°143 |
2–4 mm (single view) ~8 mm (pupil st./dup.) |
Small | Implementation of pupil steering or duplication. |
| Diffractive waveguide | 50–200 nit/lm6 | ~50°6 | ~15 mm | Medium (multilayer) | Combiner efficiency, FoV |
| Achromatic waveguide |
650–1000 nit/lm (2D EPE)197 1500–3000 nit/lm (1D EPE)199 |
~60°199 | ~15 mm | Small | Fabrication, FoV |