Display panel, multi-layer display element, and method of fabricating the same

1. A display panel comprising:

a pair of substrates faced to each other as a display material layer is sandwiched therebetween;

a plurality of pixels provided in a plane parallel with a substrate surface between the substrates; and

a plurality of alignment marks formed in different shapes and linearly arranged on at least one of the pair of the substrates at a predetermined interval for alignment in placing the display panel and an other display panel having the same alignment mark structure as the display panel in layers.

2. The display panel according to claim 1 , wherein the plurality of the alignment marks are arranged in parallel with a direction of extending an electrode to drive the plurality of the pixels.

3. The display panel according to claim 1 , wherein the predetermined interval is equal to a distance of an integral multiple of a pixel pitch.

4. The display panel according to claim 1 , wherein the alignment marks are formed to contact with two facing surfaces of the pair of the substrates.

5. The display panel according to claim 4 , comprising a spacer configured to contact with the two facing surfaces for holding an interval between the pair of the substrates,

wherein the alignment marks are formed of the same material as a material of forming the spacer in the same layer.

6. The display panel according to claim 1 , wherein the plurality of the pixels are provided in a dot matrix.

7. The display panel according to claim 1 , wherein the display material layer has liquid crystals forming a cholesteric phase.

8. A multi-layer display element comprising a plurality of display panels placed in layers,

wherein the display panel is the display panel according to claim 1 .

9. The multi-layer display element according to claim 8 , wherein the display panel has a pixel area formed of the plurality of the pixels, and

pixel areas of the display panels adjacently placed in layers are displaced in a direction of arranging the alignment marks.

10. A method of fabricating a multi-layer display element, the method comprising the steps of:

preparing a plurality of display panels, each including a pair of substrates faced to each other as a display material layer is sandwiched therebetween, a plurality of pixels provided along a display surface of the substrates, and a plurality of alignment marks formed in different shapes and linearly arranged on at least one of the pair of the substrates at a predetermined interval for alignment in placing the display panels in layers, wherein the plurality of the display panels have the same alignment mark structures;

laying the plurality of the display panels on each other;

aligning the alignment marks in different shapes formed in the adjacent display panels with each other; and

bonding the plurality of the display panels together.

11. The method according to claim 10 , wherein the plurality of the alignment marks are formed so as to be arranged in parallel with a direction of extending an electrode to drive the plurality of the pixels.

12. The method according to claim 10 , wherein the predetermined interval is equal to a distance of an integral multiple of a pixel pitch.

13. The method according to claim 10 , wherein the alignment marks are formed to contact with two facing surfaces of the pair of the substrates.

14. The method according to claim 13 , wherein the alignment marks are formed of the same material as a material of forming a spacer at the same time in the same layer, the spacer configured to contact with the two facing surfaces for holding an interval between the pair of the substrates.

15. The method according to claim 10 , wherein the plurality of the pixels are provided in a dot matrix.

16. The method according to claim 10 , wherein liquid crystals for forming a cholesteric phase are used for the display material layer.

17. The method according to claim 16 , wherein the display panels are placed in layers such that pixel areas formed of the plurality of the pixels are displaced in a direction of arranging the alignment marks.

18. The method according to claim 10 , wherein the alignment marks formed in each of the display panels are visually recognized in the same visual field, and

the display panel is moved to align the alignment marks with each other.