Optical apparatus and method
View Patent ↗An apparatus and a method are provided. The apparatus including: a light expander configured to expand light, input into the light expander, in a first dimension, and configured to provide diverging light that diverges in the first dimension; and an optical device configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension.
1. An apparatus, comprising:
a light expander configured to expand light, input into the light expander, in a first dimension, and configured to provide diverging light that diverges in the first dimension;
an optical device configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension; and
a further light expander configured to expand the light, converging in the first dimension and received from the optical device, in a second dimension substantially orthogonal to the first dimension.
2. An apparatus as claimed in claim 1 , wherein the light expander is configured to guide light, input into the light expander, prior to providing diverging light to the optical device.
3. An apparatus as claimed in claim 1 , wherein the light expander is configured to expand light, input into the light expander, in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.
4. An apparatus as claimed in claim 1 , wherein the optical device is configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension,
5. An apparatus as claimed in claim 1 , wherein the optical device is configured to redirect the diverging light within a plane substantially orthogonal to the first dimension.
6. An apparatus as claimed in claim 1 , wherein the optical device comprises a reflecting system comprising a plurality of reflecting surfaces.
7. An apparatus as claimed in claim 6 , wherein adjacent reflecting surfaces of the reflecting system are orthogonal to one another.
8. An apparatus as claimed in claim 6 , wherein the reflecting system is provided by a grooved reflector.
9. An apparatus as claimed in claim 1 , wherein the light input into the light expander represents an image displayed on a display.
10. An apparatus as claimed in claim 1 , wherein the further light expander comprises an in-coupling portion configured to receive the converging light from the optical device, and an out-coupling portion configured to output light to a user.
11. An apparatus as claimed in claim 10 , wherein the in-coupling portion of the further light expander comprises a first grating and the out-coupling portion of the further light expander comprises a second grating.
12. An apparatus as claimed in claim 1 , wherein the further light expander provides an exit pupil for the apparatus.
13. A method, comprising:
expanding light in a first dimension;
providing diverging light, that diverges in the first dimension;
redirecting the diverging light to produce converging light that converges in the first dimension; and
expanding the converging light in a second dimension, substantially orthogonal to the first dimension.
14. A method as claimed in claim 13 , wherein the light is expanded in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.
15. A method as claimed in claim 13 , wherein the diverging light is redirected to produce converging light that converges in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.
16. An apparatus, comprising:
light expanding means for expanding light, in a first dimension, and for providing diverging light that diverges in the first dimension; and
redirecting means for redirecting diverging light, received from the light expanding means, to produce converging light that converges in the first dimension; and
further light expanding means for expanding the light, converging in the first dimension and received from the redirecting means, in a second dimension substantially orthogonal to the first dimension.
17. An apparatus as claimed in claim 16 , wherein the light expanding means is for expanding light, input into the light expander, in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.
18. An apparatus as claimed in claim 16 , wherein the redirecting means is for redirecting diverging light, received from the light expander, to produce converging light that converges in the first dimension and not in a second dimension, the second dimension being substantially orthogonal to the first dimension.
19. An apparatus, comprising:
a light expander configured to expand light, input into the light expander, in a first dimension, and configured to provide diverging light that diverges in the first dimension; and
a grooved reflector configured to redirect diverging light, received from the light expander, to produce converging light that converges in the first dimension.