1. 2D/3D Switchable Liquid Crystal Lens unit for Display
MENSA

2. Market Demand

3. Glass free 3D display with lenticular lens

4. The modern demand includes 3D object and 2D text
We need switchable option from 3D to 2D.
Nice to have an arbitrary sector of display with 2D and other area with 3D simultaneously.

5. Proposed solution
Polarization dependent lens array
Bi-stable (FLC) polarization rotating layer.
Polarization selector layer followed by the polarization dependent lens layer.
The last one shows the lens effect only for one polarization of the light but no lens effect for the orthogonally polarized light.
The polarization selector stage is bi-stable, where in the first state it rotates the plane of polarization of the impinging light from the Display to 90 degree and shows 3D object thanks to lens effect. Whereas the other state does not affect plane of the polarization of the impinging Light from the Display and shows 2D mode.

6. Work description
FLC polarization 2
FLC polarization 1

7. Optics- Lens effect FLC Applied V pulse
Optical response of the FLC bi-stable polarization rotator stage.
Light from the LCD
LCD

8. Optics- No Lens effect FLC Applied V pulse
Optical response of the FLC bi-stable polarization rotator stage.
FLC
Light from the LCD
LCD

9. Selective 2D/3D sectors

10. The patterned electrode method:
Alternative solutions for 2D-3D switchable lens arrays
LC convex lens, embedded in the concave lens
nano-PDLC lens
Micro-lens structures with different top ITO electrode shapes
The patterned electrode method:
The polarization selective mode.
Jisoo Hong, Youngmin Kim, Hee-Jin Choi, Joonku Hahn, Jae-Hyeung Park, Hwi Kim, Sung-Wook Min, Ni Chen, and Byoungho Lee, "Three-dimensional display technologies of recent interest: principles, status, and issues [Invited]," Appl. Opt. 50, H87-H115 (2011)
Yu-Cheng Chang, Tai-Hsiang Jen, Chih-Hung Ting, and Yi-Pai Huang, "High-resistance liquid-crystal lens array for rotatable 2D/3D autostereoscopic display," Opt. Express 22, (2014)
Ruidong Zhu, Su Xu, Qi Hong, Shin-Tson Wu, Chiayu Lee, Chih-Ming Yang, Chang-Cheng Lo, and Alan Lien, "Polymeric-lens-embedded 2D/3D switchable display with dramatically reduced crosstalk," Appl. Opt. 53, (2014)

11. Issues and problems
Complicated fabrication for the patterned electrode i.e. relatively expensive.
Polymer stabilized LC requires tight restrictions on the index matching otherwise scattering appears.
Polarization rotator or polarization selector require TN LC panel.
All existing options provide the 2D-3D switchable function at the cost of the power consumption and for some of them it is extremely high.
Micromachines 2014, 5(2), ; doi: /mi
Jisoo Hong, Youngmin Kim, Hee-Jin Choi, Joonku Hahn, Jae-Hyeung Park, Hwi Kim, Sung-Wook Min, Ni Chen, and Byoungho Lee, "Three-dimensional display technologies of recent interest: principles, status, and issues [Invited]," Appl. Opt. 50, H87-H115 (2011)

12. Resume
We propose a 2D-3D switchable lens array unit that has two components:
Polarization dependent lens layer
Polarization rotator/selector Bi-stable layer
The polarization dependent lens layer shows lens effect for one polarization of the light while no lens effect for the orthogonal polarization of the impinging light.
The polarization rotator/selector bi-stable stage rotates the plane of polarization of the impinging light from the display and the unit shows the 3D object. Whereas in the other state the polarization rotator/selector bi-stable stage does not affect the plane of polarization of the impinging light from the display and the unit shows the 2D object.
The proposed unit, unlike other alternative, does not require power to hold any 2D or 3D mode. The unit needs power only to switch from one state to other. Therefore the unit does not consume additional power during the single mode operation.

13. Appendix

14. Diffusion mechanism of azo-dye molecule alignment
UV-light
polarization direction q
azo-dye molecule with
absorption oscillator
Azo-dye absorption oscillator (chromophore)
V. Chigrinov et al. Phys. Rev. E, (2004).

15. Light alignment Photosensitive molecules Photoalignment Layer coated
Exposure with
selected light source
Molecules aligned
To desired direction

16. Stabilization of the orientation of the azo dyes by heat polymerization
Non-polarized UV irradiation
Azo dye monomers
Photo reorientation
Liquid crystal
Heating
Heat polymerization
Polymerizable azo dye

17. Experiments